{"gene":"FLT4","run_date":"2026-06-09T23:54:44","timeline":{"discoveries":[{"year":1992,"finding":"FLT4 encodes a transmembrane receptor tyrosine kinase with seven immunoglobulin-like loops in its extracellular domain, structurally related to FLT1 and KDR/FLK1, constituting a subfamily of class III tyrosine kinases.","method":"cDNA cloning, sequencing, structural analysis","journal":"Cancer research","confidence":"High","confidence_rationale":"Tier 1 / Strong — full-length cDNA sequenced and protein structure determined; replicated by independent lab in same year (PMID:8386825)","pmids":["1327515","8386825"],"is_preprint":false},{"year":1992,"finding":"FLT4 gene maps to chromosomal region 5q33-qter (human) and chromosome 11 (mouse).","method":"Chromosomal mapping, genomic analysis","journal":"Cancer research / Genomics","confidence":"High","confidence_rationale":"Tier 2 / Strong — replicated by two independent labs in same year","pmids":["1310071","1319394"],"is_preprint":false},{"year":1993,"finding":"FLT4 protein is expressed as a ~170 kDa glycoprotein when transiently expressed in Cos-7 cells, as shown by immunoprecipitation with FLT4-specific antisera.","method":"Transient expression in Cos-7 cells, immunoprecipitation, Western blot","journal":"Oncogene","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — direct biochemical characterization, single lab","pmids":["8386825"],"is_preprint":false},{"year":1993,"finding":"FLT4 is expressed in vascular endothelial cells of developing vessels in multiple fetal organs, with overlapping but distinct expression patterns compared to FLT1 and KDR/FLK1.","method":"Northern blot, in situ hybridization in human fetal tissues","journal":"The Journal of experimental medicine","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — direct localization by in situ hybridization, single lab, multiple tissues","pmids":["8245783"],"is_preprint":false},{"year":1993,"finding":"Two FLT4 isoforms (short and long) are generated by alternative polyadenylation and subsequent alternative splicing, producing proteins differing in their C-terminal tails.","method":"cDNA cloning, genomic structure analysis, Northern blot","journal":"Oncogene","confidence":"High","confidence_rationale":"Tier 1 / Strong — molecular cloning plus genomic structure determination, replicated biochemically","pmids":["7692369"],"is_preprint":false},{"year":1994,"finding":"FLT4 does not bind VEGF and does not undergo autophosphorylation in response to VEGF. When its tyrosine kinase domain was activated via a CSF-1R/FLT4 chimera, FLT4 kinase interacted with SHC and GRB2 adaptor proteins via their SH2 domains in vitro and with SHC in cells, and stimulated thymidine incorporation in NIH3T3 fibroblasts but not in endothelial cells.","method":"Receptor chimera assay, SH2 domain binding assay, autophosphorylation assay, thymidine incorporation","journal":"Oncogene","confidence":"High","confidence_rationale":"Tier 1 / Moderate — in vitro reconstitution with chimeric receptor, mutagenesis-equivalent domain swapping, multiple orthogonal assays in single study","pmids":["7970715"],"is_preprint":false},{"year":1995,"finding":"The long isoform of FLT4 (FF4L), but not the short isoform (FF4S), can induce anchorage-independent growth of Rat-2 cells in soft agar upon CSF-1 stimulation of CSF-1R/FLT4 chimeras, demonstrating functional differences between the two isoforms. Both isoforms are highly glycosylated (~180 kDa) cell-surface kinases.","method":"Soft agar colony assay, CSF-1R/FLT4 chimeric receptor expression, biochemical characterization","journal":"Oncogene","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — functional assay distinguishing isoforms, single lab with multiple methods","pmids":["7898938"],"is_preprint":false},{"year":1997,"finding":"VEGF-C (Flt4 ligand/VRP) is the cognate ligand for FLT4; recombinant VEGF-C activates FLT4 as demonstrated by induction of tyrosyl phosphorylation and stimulates mitogenesis of lymphatic endothelial cells. VEGF-C is proteolytically processed to generate a mature ~21 kDa homodimer.","method":"BIAcore binding assay, receptor affinity chromatography, tyrosyl phosphorylation assay, mitogenesis assay","journal":"Oncogene","confidence":"High","confidence_rationale":"Tier 1 / Strong — ligand identified by affinity purification, receptor activation confirmed by phosphorylation assay, functional mitogenesis demonstrated; replicated by independent groups","pmids":["9247316"],"is_preprint":false},{"year":1997,"finding":"VRP/VEGF-C stimulation of FLT4 in hematopoietic HEL cells induces formation of a signaling complex including Shc, Grb2, and SOS at the activated receptor, activates RAFTK (focal adhesion kinase family member) and its association with Grb2, activates JNK, and induces paxillin phosphorylation.","method":"Co-immunoprecipitation, kinase assay, Western blot for phosphorylation","journal":"Blood","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — multiple co-IP and phosphorylation assays, single lab","pmids":["9345034"],"is_preprint":false},{"year":1998,"finding":"VEGF-D is a ligand for both VEGFR-2 (Flk1) and VEGFR-3 (Flt4) and can activate these receptors; the receptor-binding capacity resides in the VEGF-homology domain (mature form). VEGF-D does not bind VEGFR-1.","method":"Receptor-binding assays, receptor activation assays, deletion mutant analysis","journal":"Proceedings of the National Academy of Sciences","confidence":"High","confidence_rationale":"Tier 1 / Strong — direct receptor-binding and activation assays with deletion constructs, published in high-impact journal with extensive citations","pmids":["9435229"],"is_preprint":false},{"year":2000,"finding":"VEGF-C signaling through VEGFR-3 regulates VEGFR-2 signaling: in VEGFR-3-deficient embryos, excess VEGF-C signals through VEGFR-2, causing disturbed vasculogenesis and suppressed hematopoiesis. VEGFR-3 binding of VEGF-C limits the amount available for VEGFR-2 activation.","method":"P-Sp/OP9 coculture, VEGFR-3-deficient mouse embryos, soluble receptor competitor assays","journal":"Blood","confidence":"High","confidence_rationale":"Tier 2 / Strong — genetic KO combined with ligand competition experiments in embryonic culture model, multiple orthogonal approaches","pmids":["11090062"],"is_preprint":false},{"year":2001,"finding":"VEGFR-3 promoter contains TATA-less proximal sequences with endothelial cell-specific transcriptional activity in transfection assays; a 1.6 kb promoter fragment directed weak lymphatic endothelial expression of LacZ in transgenic mice.","method":"Reporter gene transfection, transgenic mouse analysis","journal":"FASEB journal","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — in vitro and in vivo promoter activity assays, single lab","pmids":["11292664"],"is_preprint":false},{"year":2002,"finding":"VEGF-C/VEGFR-3 signaling negatively modulates VEGFR-2 activity in endothelial cells: an antagonistic VEGFR-3 antibody (AFL4) induced VEGF-A-dependent EC dispersion similar to VEGFR-2 activation, suggesting VEGFR-3 suppresses VEGFR-2 signaling to maintain vascular integrity.","method":"ES cell-derived endothelial culture, antagonistic monoclonal antibody treatment, cytological analysis","journal":"Blood","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — functional assay with specific antibody in defined in vitro system, single lab","pmids":["12393458"],"is_preprint":false},{"year":2003,"finding":"VEGFR-3 is expressed on corneal dendritic cells (CD11c+CD45+CD11b+, MHC class II-negative immature DCs of monocytic lineage), which also upregulate VEGF-C during inflammation; this represents expression of VEGFR-3 outside the endothelial compartment.","method":"Immunofluorescence, flow cytometry, phenotypic characterization of corneal cells","journal":"The American journal of pathology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — direct cell phenotyping with multiple markers, single lab","pmids":["12819011"],"is_preprint":false},{"year":2009,"finding":"In zebrafish, a loss-of-function mutation in the kinase insert region of flt4 impairs lymphatic vascular development. Dll4 suppresses arterial responsiveness to Vegfc/Flt4 signaling: loss of dll4 causes arterial hyperbranching driven by Vegfc/Flt4, and overexpression of dll4 inhibits Vegfc/Flt4-dependent angiogenesis.","method":"Forward genetic screen, zebrafish mutant characterization, morpholino knockdown, genetic epistasis","journal":"Development","confidence":"High","confidence_rationale":"Tier 2 / Strong — loss-of-function genetics plus epistasis experiments in vivo, replicated with multiple genetic tools","pmids":["19906867"],"is_preprint":false},{"year":2009,"finding":"Sumoylation of the transcription factor Prox1 at Lys556 is required for Prox1 to bind DNA, activate transcription, and induce VEGFR3 expression in endothelial cells. Mutation K556R or SENP2-mediated desumoylation abolishes Prox1-induced VEGFR3 expression and lymphatic phenotypes.","method":"In vitro sumoylation assay, site-directed mutagenesis, reporter gene assay, ectopic expression in endothelial cells","journal":"Journal of cell science","confidence":"High","confidence_rationale":"Tier 1 / Moderate — in vitro sumoylation assay plus mutagenesis plus functional rescue/loss experiments, single lab with multiple orthogonal methods","pmids":["19706680"],"is_preprint":false},{"year":2009,"finding":"A homozygous VEGFR3 mutation (A855T, in the ATP-binding domain) causes recessive primary congenital lymphedema; the mutant receptor shows impaired ligand-induced internalization, reduced ERK1/2 activity, and reduced phosphorylation compared to wild-type, though not as severely as kinase-dead mutations.","method":"Patient genetic analysis, receptor function assays (internalization, phosphorylation, ERK activation)","journal":"Journal of medical genetics","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — direct receptor functional assays on patient-derived mutation, single lab","pmids":["19289394"],"is_preprint":false},{"year":2010,"finding":"VEGFR-3 ligand-binding domain and kinase activity are required for lymphangiogenesis but not for angiogenesis. Both wild-type and kinase-dead VEGFR-3 can form heterodimers with VEGFR-2 and decrease phospho-VEGFR-2 and phospho-ERK1/2 levels in endothelial cells treated with VEGF-A.","method":"Conditional knock-in mice (ligand-binding domain deletion and kinase-dead point mutation), co-immunoprecipitation for heterodimer detection, phosphorylation assays","journal":"Cell research","confidence":"High","confidence_rationale":"Tier 1 / Strong — two complementary genetic mouse models plus biochemical heterodimer and signaling assays, single lab with multiple orthogonal methods","pmids":["20697430"],"is_preprint":false},{"year":2010,"finding":"Tbx1 transcription factor activates Vegfr3 transcription by binding to an enhancer element in the Vegfr3 gene in endothelial cells; conditional deletion of Tbx1 in ECs causes widespread lymphangiogenesis defects.","method":"ChIP, reporter assay, conditional knockout mouse, in vitro transcription assays","journal":"The Journal of cell biology","confidence":"High","confidence_rationale":"Tier 1 / Strong — direct ChIP showing Tbx1 binding to Vegfr3 enhancer plus functional genetic validation in vivo","pmids":["20439995"],"is_preprint":false},{"year":2011,"finding":"R-spondin1 (Rspo1)/Wnt signaling promotes angiogenesis in zebrafish through the Vegfc/Vegfr3(Flt4) axis: Vegfc expression is dependent on Rspo1 and Wnt, and Vegfc/Vegfr3 are necessary downstream of Rspo1-Wnt for angiogenesis.","method":"Forward genetic screen in zebrafish, morpholino knockdown, epistasis analysis, endothelial-autonomous Wnt inhibition","journal":"Development","confidence":"High","confidence_rationale":"Tier 2 / Strong — genetic epistasis with multiple loss-of-function tools in vivo establishing pathway order","pmids":["22007135"],"is_preprint":false},{"year":2012,"finding":"Notch signaling strongly suppresses VEGFR3 expression; loss of Notch leads to VEGFR3 upregulation and excessive sprouting. VEGFR3 kinase-activity inhibitors (but not ligand-blocking antibodies) suppress sprouting in low-Notch endothelium, indicating VEGFR3 can signal in a ligand-independent manner when Notch is inhibited.","method":"Inducible loss-of-function genetics in vivo, pharmacological inhibitors, antibody blocking in retinal vasculature","journal":"Nature","confidence":"High","confidence_rationale":"Tier 2 / Strong — combined genetic and pharmacological approaches in vivo with rigorous controls, published in Nature","pmids":["22426001"],"is_preprint":false},{"year":2012,"finding":"miR-1236 (a mirtron) binds the 3' UTR of VEGFR3 mRNA, causing translational inhibition and specifically reducing VEGFR3 (but not VEGFR2) expression in human lymphatic endothelial cells; overexpression decreases VEGFR3 signaling, LEC migration, tube formation, and in vivo lymphangiogenesis.","method":"3' UTR luciferase reporter assay, miRNA overexpression in LECs, in vivo lymphangiogenesis assay","journal":"Arteriosclerosis, thrombosis, and vascular biology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — direct 3' UTR binding assay plus functional validation, single lab","pmids":["22223733"],"is_preprint":false},{"year":2014,"finding":"VEGF-C activates AKT signaling via formation of a VEGFR3/VEGFR2 heterodimer complex (requiring neuropilin-1), while ERK1/2 is activated via VEGFR3 homodimers. Silencing VEGFR2 or neuropilin-1 abolishes VEGF-C-induced AKT but not ERK activation. Vascular endothelial phosphotyrosine phosphatase (VE-PTP) restrains both ERK and AKT pathways downstream of VEGFR3.","method":"Co-immunoprecipitation, siRNA silencing, phosphorylation assays in primary human lymphatic endothelial cells","journal":"Arteriosclerosis, thrombosis, and vascular biology","confidence":"High","confidence_rationale":"Tier 2 / Moderate — multiple orthogonal methods (co-IP, siRNA, kinase assays) dissecting pathway bifurcation, single lab","pmids":["25524775"],"is_preprint":false},{"year":2014,"finding":"Integrin-linked kinase (ILK) impedes interaction between VEGFR3 and β1 integrin; mechanical stimulation disrupts ILK-β1 integrin assembly, releasing β1 integrin to interact with VEGFR3 and hyper-activate VEGFR3 signaling. Endothelial-specific ILK deletion leads to excessive VEGFR3 phosphorylation and lymphatic overgrowth rescued by Itgb1 haploinsufficiency.","method":"Endothelial-specific conditional knockout mice, co-immunoprecipitation, phosphorylation assays, genetic rescue experiments","journal":"The EMBO journal","confidence":"High","confidence_rationale":"Tier 2 / Strong — genetic interaction confirmed by double conditional KO rescue plus biochemical co-IP, multiple orthogonal methods","pmids":["30518533"],"is_preprint":false},{"year":2015,"finding":"VEGFR2 is required for postnatal retinal angiogenesis independently of VEGFR3 and Notch; VEGFR2 is required for DLL4 upregulation and for VEGFR3 functions in angiogenesis. In contrast, VEGFR3 (but not VEGFR2) is essential for postnatal lymphangiogenesis and adult lymphatic vessel maintenance.","method":"Conditional deletion of Vegfr2 and Vegfr3 in mice, Notch pathway inhibitor treatment, retinal vascular phenotyping","journal":"Proceedings of the National Academy of Sciences","confidence":"High","confidence_rationale":"Tier 2 / Strong — conditional double knockouts with epistasis analysis, published in high-impact journal","pmids":["25561555"],"is_preprint":false},{"year":2016,"finding":"VEGFR3 is expressed on tumor-associated macrophages (TAMs) that infiltrate chemotherapy-treated tumors; VEGFR3-expressing macrophages induce lymphangiogenesis in a VEGF-C/VEGFR3-dependent manner. Blocking VEGF-C/VEGFR3 inhibits pro-metastatic macrophage activity.","method":"VEGFR3 blocking in murine tumor models, macrophage transfer experiments, in vivo lymphangiogenesis assay","journal":"Cell reports","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — macrophage transfer and antibody blocking experiments in vivo, single lab","pmids":["27783948"],"is_preprint":false},{"year":2017,"finding":"VEGFR3 limits VEGFR2 expression and VEGF/VEGFR2 pathway activity: deletion of Vegfr3 in blood vascular endothelial cells upregulates VEGFR2 protein and phosphorylation, reduces VE-cadherin at cell junctions, and exacerbates vascular permeability. Concurrent Vegfr2 deletion prevents the excessive permeability seen in Vegfr3-deleted mice.","method":"Conditional Vegfr3 deletion in mice, VEGFR3 siRNA in cultured ECs, VEGFR2 phosphorylation assay, VE-cadherin localization, genetic rescue (Vegfr2 co-deletion)","journal":"Circulation research","confidence":"High","confidence_rationale":"Tier 2 / Strong — conditional KO in vivo plus in vitro silencing plus genetic rescue, multiple orthogonal methods","pmids":["28298294"],"is_preprint":false},{"year":2018,"finding":"In diabetes, ROS-induced c-Src-dependent (but VEGF-C-independent) VEGFR3 phosphorylation upregulates AP-1, which increases epsin expression; elevated epsins bind and promote degradation of newly synthesized VEGFR3 in the Golgi, reducing cell-surface VEGFR3 availability and impairing lymphangiogenesis.","method":"Lymphatic-specific epsin double KO mice, endocytosis assays, VEGFR3 phosphorylation and degradation assays, corneal micropocket and Matrigel assays","journal":"The Journal of clinical investigation","confidence":"High","confidence_rationale":"Tier 2 / Strong — genetic KO model plus mechanistic phosphorylation/degradation assays, multiple orthogonal methods","pmids":["30102256"],"is_preprint":false},{"year":2018,"finding":"Heterogeneous deletion of Vegfr3 in lymphatic endothelial cells causes VEGFR3- cells to non-cell-autonomously drive lymphatic hyperplasia by inducing proliferation of neighboring VEGFR3+ LECs through contact-dependent reduction of Notch signaling.","method":"Inducible mosaic Vegfr3 deletion in mice, Notch signaling readouts, clonal analysis","journal":"Nature communications","confidence":"High","confidence_rationale":"Tier 2 / Strong — inducible mosaic genetics in vivo with mechanistic Notch pathway analysis, multiple orthogonal approaches","pmids":["29615616"],"is_preprint":false},{"year":2018,"finding":"CLEC14A forms a complex with VEGFR-3 in endothelial cells; loss of CLEC14A reduces VEGFR-3 expression with concomitant increases in VEGFR-2 expression and downstream signaling, demonstrating CLEC14A as a regulator of VEGFR-2/VEGFR-3 balance.","method":"Co-immunoprecipitation, CLEC14A knockout mice, receptor expression and signaling assays","journal":"The Journal of clinical investigation","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — co-IP plus genetic KO with receptor-level readouts, single lab","pmids":["27991863"],"is_preprint":false},{"year":2018,"finding":"uPARAP endocytic receptor forms a complex with both VEGFR-2 and VEGFR-3, restricts their heterodimerization, and promotes VEGFR-3 signaling through the Crk-II/JNK/paxillin/Rac1 pathway during VEGF-C-driven lymphangiogenesis. Loss of uPARAP leads to hyperbranched lymphatic vasculature in pathological conditions.","method":"Co-immunoprecipitation, uPARAP genetic knockout, VEGFR heterodimer assays, pathway inhibition, in vivo lymphangiogenesis models","journal":"Nature communications","confidence":"High","confidence_rationale":"Tier 2 / Strong — co-IP defining complex, genetic KO in vivo, pharmacological rescue with multiple pathway readouts","pmids":["30518756"],"is_preprint":false},{"year":2018,"finding":"VEGFR-3 tyrosine kinase inactivation (Chy mouse with I1053F mutation) leads to retention of triglycerides in enterocytes, decreased postprandial plasma TGs, and reduced nitric oxide levels after fat bolus, demonstrating a role for VEGFR-3 signaling in chylomicron entry into intestinal lacteals.","method":"Chy mouse model (kinase-dead VEGFR3), lipid absorption assays, NO measurement, enterocyte histology","journal":"Frontiers in physiology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — established mouse model with specific kinase-dead mutation, multiple functional readouts, single lab","pmids":["30618798"],"is_preprint":false},{"year":2020,"finding":"In zebrafish cardiac valve development, Vegfr3/Flt4 is restricted to abluminal endocardial cells by blood flow-activated Notch and Klf2a signaling pathways. Loss of Vegfr3 disrupts valve morphogenesis and causes Notch activation in abluminal cells, revealing antagonistic roles of Vegfr3 (abluminal) and Notch (luminal) in shaping valve leaflets.","method":"Zebrafish genetic mutants and transgenic lines, mechanosensitive pathway analysis, live imaging","journal":"Cell reports","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — genetic loss-of-function in zebrafish with epistasis to Notch pathway, single lab","pmids":["32668254"],"is_preprint":false},{"year":2021,"finding":"FLT4/VEGFR3 recruits AMP-activated protein kinase (AMPK) and directly phosphorylates AMPK-α subunit at Y247 and Y441/Y442 upon bacterial infection in macrophages, thereby coordinating glycolytic reprogramming, autophagy (MAP1LC3 activation), and suppression of CASP1-dependent inflammasome activation/pyroptosis for bacterial elimination.","method":"FLT4 mutant (extracellular domain deletion) macrophages, AMPK phosphorylation assays, metabolomics, autophagy assays, AICAR rescue experiments","journal":"Autophagy","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — phosphorylation site identification with functional mutant analysis and pharmacological rescue, single lab","pmids":["34632918"],"is_preprint":false},{"year":2021,"finding":"VEGFC/VEGFR3/ERK signaling directly induces cell-cycle arrest (G1) in venous and lymphatic endothelial precursors in zebrafish, promoting expression of p53 and CDK inhibitors p27/p21, and this G1 arrest is required for vascular sprouting and differentiation.","method":"Transgenic zebrafish (cell cycle reporters), VEGFC/VEGFR3 manipulation, CDK inhibitor overexpression, live confocal imaging","journal":"Cell reports","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — in vivo live imaging with genetic manipulation establishing causal link between VEGFR3/ERK and cell-cycle arrest, single lab","pmids":["34133928"],"is_preprint":false},{"year":2021,"finding":"Mitochondrial complex III activity in lymphatic endothelial cells is required for maintaining H3K4me3 and H3K27ac at the Vegfr3 (and Prox1) genomic loci; loss of complex III causes specific downregulation of Vegfr3 and loss of LEC fate.","method":"Conditional deletion of mitochondrial complex III QPC subunit in LECs, ChIP for histone marks, gene expression analysis","journal":"Science advances","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — conditional genetic KO with direct chromatin modification assays, single lab","pmids":["33931446"],"is_preprint":false},{"year":2022,"finding":"Ang2 secreted from lymphatic endothelial cells upon VEGF-C stimulation activates Tie2 and Tie1 receptors to fully activate Akt downstream of PI3K, which is required for cell-surface presentation of VEGFR3 on LECs. Blockade of Ang2 or deletion of Tie receptors reduces VEGFR3 surface levels and inhibits lymphangiogenesis.","method":"Gene deletion of Tie1, Tie2, Ang2, PI3K-p110α in LECs; Ang2-blocking antibody; VEGFR3 surface expression assays; adult lymphangiogenesis models","journal":"The Journal of clinical investigation","confidence":"High","confidence_rationale":"Tier 2 / Strong — multiple genetic and pharmacological tools with direct VEGFR3 surface expression readout, replicated across neonatal and adult models","pmids":["35763346"],"is_preprint":false},{"year":2023,"finding":"VEGFR3 is required for button junction formation in lymphatic capillaries; loss of Flt4 in lymphatic-specific knockout mice prevents button junction development and impairs interstitial absorption. Mechanistically, FLT4 knockdown reduces NOTCH1 expression and activation, and overexpression of the NOTCH1 intracellular domain in Flt4 knockout vessels rescues button junction formation.","method":"Lymphatic-specific Flt4 knockout mice, junction morphology analysis, NOTCH1 overexpression rescue, absorption assays","journal":"Cell reports","confidence":"High","confidence_rationale":"Tier 2 / Strong — genetic KO plus mechanistic rescue with NOTCH1 intracellular domain, multiple functional readouts","pmids":["37454290"],"is_preprint":false},{"year":2023,"finding":"VEGFR-3 blockade (monoclonal antibody, soluble VEGF-C/D trap, or lymphatic endothelium-specific Vegfr3 deletion) causes regression and functional impairment of dural lymphatic vessels but has no effect on CNS autoimmunity development in mice.","method":"VEGFR3-blocking antibody, soluble decoy receptor, inducible conditional Vegfr3 deletion; EAE autoimmune neuroinflammation model","journal":"Science immunology","confidence":"High","confidence_rationale":"Tier 2 / Strong — three independent VEGFR3 inhibition strategies with functional lymphatic and immunological readouts","pmids":["37058549"],"is_preprint":false},{"year":2023,"finding":"VEGF-C secreted by virally infected neurons activates VEGFR-3 on CNS macrophages, suppressing TNF-α secretion and reducing neuron apoptosis. Vegfr3 ligand-binding domain deletion in myeloid cells or VEGFR-3 kinase inhibitor treatment exacerbates encephalitis severity and neuronal damage.","method":"VEGFR-3 ligand-binding domain knockout in myeloid cells (Vegfr3ΔLBD/ΔLBD), VEGFR-3 kinase inhibitor, co-culture assays with conditioned medium, JEV infection mouse model","journal":"Cell reports","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — myeloid-specific genetic model plus pharmacological inhibition, single lab","pmids":["37167063"],"is_preprint":false}],"current_model":"FLT4/VEGFR3 is a class III receptor tyrosine kinase that is activated by VEGF-C and VEGF-D (but not VEGF-A) to drive lymphangiogenesis and angiogenesis through homodimers (activating ERK) and heterodimers with VEGFR2 (activating AKT via neuropilin-1); its surface expression is controlled by Ang2/Tie/PI3K signaling, epsin-mediated Golgi degradation, and transcriptional regulators including Prox1 (sumoylation-dependent) and Tbx1; it modulates VEGFR2 activity both positively (via ligand sequestration) and negatively (by limiting VEGFR2 expression in quiescent endothelium), thereby regulating vascular permeability; in angiogenic tip cells it activates Notch to promote tip-to-stalk conversion and is itself suppressed by Notch in a feedback loop; it forms button junctions in lymphatic capillaries via NOTCH1 activation; in macrophages it coordinates bacterial clearance by phosphorylating AMPK and in cardiac valve morphogenesis it is restricted to abluminal endocardial cells to antagonize luminal Notch signaling; loss-of-function mutations in humans cause Milroy disease (autosomal dominant primary lymphedema), while gain-of-function amplification co-occurs with MYC in radiation-induced angiosarcoma."},"narrative":{"mechanistic_narrative":"FLT4/VEGFR3 is a class III receptor tyrosine kinase, structurally related to FLT1 and KDR, that drives lymphatic and vascular endothelial development by transducing signals from the proteolytically processed ligands VEGF-C and VEGF-D [PMID:1327515, PMID:8386825, PMID:9247316, PMID:9435229]. Unlike VEGF-A, these ligands induce receptor autophosphorylation, and the activated kinase couples to SHC/GRB2 adaptors to engage downstream signaling [PMID:7970715, PMID:9247316]. VEGFR3 bifurcates its output: VEGFR3 homodimers activate ERK1/2, while VEGF-C-driven AKT activation requires a VEGFR3/VEGFR2 heterodimer dependent on neuropilin-1, with VE-PTP restraining both arms [PMID:25524775]. Its ligand-binding and kinase activities are required for lymphangiogenesis but not angiogenesis, and its kinase activity supports lymphatic vessel maintenance and chylomicron uptake by intestinal lacteals [PMID:20697430, PMID:25561555, PMID:30618798]. VEGFR3 also negatively modulates VEGFR2: by sequestering VEGF-C and by limiting VEGFR2 protein levels, VEGFR3 preserves VE-cadherin junctions and restrains vascular permeability in quiescent endothelium [PMID:11090062, PMID:28298294]. VEGFR3 and Notch operate in reciprocal feedback—Notch suppresses VEGFR3 expression while VEGFR3 promotes NOTCH1-dependent button junction formation in lymphatic capillaries, and mosaic loss of VEGFR3 drives non-cell-autonomous hyperplasia through reduced Notch signaling [PMID:22426001, PMID:29615616, PMID:37454290]. Surface availability of VEGFR3 is tightly controlled by Ang2/Tie/PI3K-AKT signaling and by epsin-mediated Golgi degradation, while its transcription is governed by sumoylated Prox1, Tbx1, and mitochondrial complex III-dependent histone modifications at the Vegfr3 locus [PMID:19706680, PMID:20439995, PMID:30102256, PMID:33931446, PMID:35763346]. Beyond endothelium, VEGFR3 is expressed on macrophages and dendritic cells, where it directs lymphangiogenesis and, in infected macrophages, phosphorylates AMPK-α to coordinate glycolytic reprogramming, autophagy, and inflammasome suppression [PMID:12819011, PMID:27783948, PMID:34632918]. Loss-of-function VEGFR3 mutations cause primary congenital lymphedema [PMID:19289394].","teleology":[{"year":1992,"claim":"Established FLT4 as a transmembrane receptor tyrosine kinase belonging to the VEGFR/class III subfamily, defining its molecular identity before any ligand or function was known.","evidence":"cDNA cloning, sequencing, and structural analysis; chromosomal mapping","pmids":["1327515","8386825","1310071","1319394"],"confidence":"High","gaps":["No ligand identified","No functional or signaling role established"]},{"year":1993,"claim":"Localized FLT4 expression to vascular endothelium of developing vessels and revealed isoform diversity, hinting at a developmental vascular role and tail-dependent functional variation.","evidence":"In situ hybridization in fetal tissues; cDNA/genomic analysis of two C-terminal isoforms; biochemical characterization of the ~170 kDa glycoprotein","pmids":["8245783","7692369","8386825"],"confidence":"Medium","gaps":["Functional difference between isoforms not yet tested","Signaling output unknown"]},{"year":1994,"claim":"Showed FLT4 does not respond to VEGF-A and, using a chimeric receptor, that its activated kinase couples to SHC/GRB2 adaptors, distinguishing it from FLT1/KDR and defining its proximal signaling.","evidence":"CSF-1R/FLT4 chimera, SH2-domain binding assays, autophosphorylation and thymidine incorporation assays","pmids":["7970715"],"confidence":"High","gaps":["Cognate ligand not identified","Chimera does not establish native ligand-dependent signaling"]},{"year":1995,"claim":"Demonstrated the long FLT4 isoform confers transforming potential, linking C-terminal tail differences to distinct biological outputs.","evidence":"Soft agar colony assay with CSF-1R/FLT4 chimeras in Rat-2 cells","pmids":["7898938"],"confidence":"Medium","gaps":["Relies on chimeric receptor not native ligand","Mechanism of isoform-specific transformation unresolved"]},{"year":1997,"claim":"Identified VEGF-C as the cognate ligand activating FLT4 and mapped a downstream Shc/Grb2/SOS, RAFTK, JNK and paxillin signaling complex, converting the orphan receptor into a defined lymphatic mitogenic pathway.","evidence":"BIAcore binding, affinity chromatography, phosphorylation and mitogenesis assays; co-IP and kinase assays in HEL cells","pmids":["9247316","9345034"],"confidence":"High","gaps":["Second ligand and receptor heterodimerization not yet addressed","In vivo lymphatic role not yet tested"]},{"year":1998,"claim":"Defined VEGF-D as a second ligand shared with VEGFR-2, broadening the receptor's ligand repertoire and foreshadowing VEGFR2/VEGFR3 crosstalk.","evidence":"Receptor-binding and activation assays with deletion mutants","pmids":["9435229"],"confidence":"High","gaps":["Functional consequences of dual-receptor binding unclear","No structural model of ligand-receptor engagement"]},{"year":2000,"claim":"Revealed that VEGFR3 controls VEGFR2 signaling by sequestering VEGF-C, establishing the first inter-receptor regulatory mechanism.","evidence":"P-Sp/OP9 coculture, VEGFR3-deficient mouse embryos, soluble receptor competition","pmids":["11090062"],"confidence":"High","gaps":["Molecular basis of crosstalk (heterodimer vs. ligand competition) not separated","Adult vascular consequences untested"]},{"year":2001,"claim":"Characterized the VEGFR3 promoter as a TATA-less endothelial-specific element, opening study of its transcriptional control.","evidence":"Reporter transfection and transgenic mouse promoter assays","pmids":["11292664"],"confidence":"Medium","gaps":["Trans-acting factors not identified","Weak lymphatic activity suggests missing enhancers"]},{"year":2002,"claim":"Showed VEGFR3 negatively modulates VEGFR2 activity to maintain vascular integrity, extending its regulatory role to endothelial behavior.","evidence":"Antagonistic VEGFR3 antibody (AFL4) in ES-derived endothelial cultures with cytological analysis","pmids":["12393458"],"confidence":"Medium","gaps":["Antibody mechanism (block vs. activate) ambiguous","In vivo permeability link not established"]},{"year":2003,"claim":"Documented VEGFR3 expression on immature dendritic cells, the first evidence of a non-endothelial functional compartment.","evidence":"Immunofluorescence and flow cytometry of corneal dendritic cells","pmids":["12819011"],"confidence":"Medium","gaps":["Function of VEGFR3 on DCs not defined","Signaling in myeloid cells unaddressed"]},{"year":2009,"claim":"Connected VEGFR3 to transcriptional and developmental control circuits, showing Prox1 sumoylation drives VEGFR3 expression, Dll4/Notch restrains Vegfc/Flt4 angiogenic responses, and a human kinase-domain mutation causes recessive lymphedema.","evidence":"In vitro sumoylation and reporter assays; zebrafish forward genetics and epistasis; patient mutation functional assays","pmids":["19706680","19906867","19289394"],"confidence":"High","gaps":["Mechanism coupling Notch to VEGFR3 expression not yet defined","Allelic spectrum of human disease incomplete"]},{"year":2010,"claim":"Separated VEGFR3 requirements for lymphangiogenesis versus angiogenesis and showed kinase-independent heterodimer suppression of VEGFR2, and identified Tbx1 as a direct transcriptional activator of Vegfr3.","evidence":"Conditional knock-in mice (ligand-binding-deletion and kinase-dead); co-IP heterodimer detection; ChIP and conditional Tbx1 knockout","pmids":["20697430","20439995"],"confidence":"High","gaps":["Structural basis of heterodimer-mediated VEGFR2 suppression unknown","Other enhancer-binding factors not catalogued"]},{"year":2011,"claim":"Placed Vegfc/Vegfr3 downstream of Rspo1/Wnt signaling, embedding the receptor in a defined upstream developmental cascade.","evidence":"Zebrafish forward genetics, morpholino knockdown, endothelial-autonomous Wnt inhibition, epistasis","pmids":["22007135"],"confidence":"High","gaps":["Direct vs. indirect Wnt-to-Vegfc link not resolved","Mammalian conservation untested in this study"]},{"year":2012,"claim":"Defined a Notch–VEGFR3 feedback loop and ligand-independent VEGFR3 kinase signaling, and identified miR-1236 as a post-transcriptional brake, refining the control of endothelial sprouting.","evidence":"Inducible Notch loss-of-function with pharmacological/antibody dissection in retina; 3'UTR luciferase and miRNA overexpression in LECs","pmids":["22426001","22223733"],"confidence":"High","gaps":["Mechanism of ligand-independent kinase activation undefined","Physiological miR-1236 regulation not established in vivo"]},{"year":2014,"claim":"Dissected the VEGFR3 signaling bifurcation—ERK via homodimers, AKT via NRP1-dependent VEGFR2 heterodimers—and identified mechanotransductive control through ILK/β1-integrin.","evidence":"Co-IP, siRNA silencing, phosphorylation assays in LECs; endothelial-specific ILK knockout with Itgb1 genetic rescue","pmids":["25524775","30518533"],"confidence":"High","gaps":["Structural geometry of the homodimer vs heterodimer outputs not resolved","How β1 integrin hyperactivates VEGFR3 mechanistically unclear"]},{"year":2015,"claim":"Genetically separated VEGFR2 and VEGFR3 requirements, fixing VEGFR3 as essential for lymphangiogenesis and lymphatic maintenance but dispensable for retinal angiogenesis.","evidence":"Conditional double knockouts in mice with Notch inhibition and retinal phenotyping","pmids":["25561555"],"confidence":"High","gaps":["Context-dependence of VEGFR3 angiogenic contribution not fully mapped"]},{"year":2016,"claim":"Established a tumor-promoting role for VEGFR3 on macrophages, where VEGF-C/VEGFR3 drives lymphangiogenesis and pro-metastatic activity.","evidence":"VEGFR3 blockade and macrophage transfer in murine tumor models","pmids":["27783948"],"confidence":"Medium","gaps":["Macrophage-intrinsic VEGFR3 signaling not defined","Single-lab tumor model"]},{"year":2017,"claim":"Showed VEGFR3 limits VEGFR2 protein levels to protect endothelial junctions and restrain permeability, with VEGFR2 co-deletion rescuing the phenotype.","evidence":"Conditional Vegfr3 deletion, EC siRNA, VEGFR2 phosphorylation and VE-cadherin assays, Vegfr2 co-deletion rescue","pmids":["28298294"],"confidence":"High","gaps":["Mechanism by which VEGFR3 limits VEGFR2 abundance unknown","Relation to ligand-sequestration model not unified"]},{"year":2018,"claim":"Uncovered multiple layers of VEGFR3 surface and activity control—epsin-mediated Golgi degradation in diabetes, CLEC14A and uPARAP complexes balancing VEGFR2/VEGFR3, non-cell-autonomous Notch-dependent hyperplasia, and a chylomicron-absorption role.","evidence":"Lymphatic epsin double KO and degradation assays; CLEC14A and uPARAP co-IP and KO; mosaic Vegfr3 deletion with Notch readouts; Chy kinase-dead mouse lipid assays","pmids":["30102256","27991863","30518756","29615616","30618798"],"confidence":"High","gaps":["Whether these regulators converge on a single trafficking node is unclear","uPARAP/CLEC14A direct binding interfaces undefined"]},{"year":2021,"claim":"Expanded VEGFR3 outputs to direct AMPK phosphorylation in macrophages for antibacterial defense, ERK-driven cell-cycle arrest in endothelial precursors, and a mitochondrial complex III–chromatin axis sustaining Vegfr3 expression.","evidence":"FLT4 mutant macrophage AMPK phosphorylation/autophagy/metabolomics assays; zebrafish cell-cycle reporters; LEC complex III conditional KO with histone-mark ChIP","pmids":["34632918","34133928","33931446"],"confidence":"Medium","gaps":["Direct AMPK phosphorylation needs structural/kinetic confirmation","Single-lab findings for each mechanism"]},{"year":2022,"claim":"Defined an Ang2/Tie/PI3K-AKT requirement for cell-surface presentation of VEGFR3, linking angiopoietin signaling to receptor availability.","evidence":"Tie1, Tie2, Ang2, PI3K-p110α deletions and Ang2-blocking antibody with VEGFR3 surface assays across neonatal and adult models","pmids":["35763346"],"confidence":"High","gaps":["Molecular step linking AKT to VEGFR3 trafficking unidentified"]},{"year":2023,"claim":"Established VEGFR3 control of NOTCH1-dependent button junction formation, a dural-lymphatic role separable from CNS autoimmunity, and a neuroprotective VEGF-C/VEGFR3 axis on CNS macrophages.","evidence":"Lymphatic-specific Flt4 KO with NOTCH1-ICD rescue; three VEGFR3-inhibition strategies in EAE; myeloid Vegfr3ΔLBD model in JEV encephalitis","pmids":["37454290","37058549","37167063"],"confidence":"High","gaps":["How VEGFR3 induces NOTCH1 expression mechanistically unresolved","Macrophage VEGFR3 signaling pathway to TNF-α suppression undefined"]},{"year":null,"claim":"How VEGFR3 toggles between ligand-dependent and ligand-independent signaling, and the unified structural/trafficking logic that integrates VEGFR2 crosstalk, Notch feedback, and surface-expression control, remains unresolved.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No structural model of the VEGFR3 homodimer vs VEGFR2 heterodimer signaling states","Mechanism of ligand-independent kinase activation undefined","Convergence point of the multiple surface/abundance regulators unknown"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0140096","term_label":"catalytic activity, acting on a protein","supporting_discovery_ids":[5,7,22,33]},{"term_id":"GO:0016740","term_label":"transferase activity","supporting_discovery_ids":[0,7,33]},{"term_id":"GO:0048018","term_label":"receptor ligand activity","supporting_discovery_ids":[7,9]},{"term_id":"GO:0060089","term_label":"molecular transducer activity","supporting_discovery_ids":[7,17,22]}],"localization":[{"term_id":"GO:0005886","term_label":"plasma membrane","supporting_discovery_ids":[6,16,36]},{"term_id":"GO:0005794","term_label":"Golgi apparatus","supporting_discovery_ids":[27]}],"pathway":[{"term_id":"R-HSA-162582","term_label":"Signal Transduction","supporting_discovery_ids":[7,17,22]},{"term_id":"R-HSA-1266738","term_label":"Developmental Biology","supporting_discovery_ids":[14,17,24,32]},{"term_id":"R-HSA-168256","term_label":"Immune System","supporting_discovery_ids":[13,25,33,39]},{"term_id":"R-HSA-9612973","term_label":"Autophagy","supporting_discovery_ids":[33]}],"complexes":["VEGFR3/VEGFR2 heterodimer","VEGFR3/uPARAP/VEGFR2 complex","VEGFR3/CLEC14A complex"],"partners":["KDR","NRP1","SHC","GRB2","CLEC14A","UPARAP","ITGB1","PRKAA"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"P35916","full_name":"Vascular endothelial growth factor receptor 3","aliases":["Fms-like tyrosine kinase 4","FLT-4","Tyrosine-protein kinase receptor FLT4"],"length_aa":1363,"mass_kda":152.8,"function":"Tyrosine-protein kinase that acts as a cell-surface receptor for VEGFC and VEGFD, and plays an essential role in adult lymphangiogenesis and in the development of the vascular network and the cardiovascular system during embryonic development. Promotes proliferation, survival and migration of endothelial cells, and regulates angiogenic sprouting. Signaling by activated FLT4 leads to enhanced production of VEGFC, and to a lesser degree VEGFA, thereby creating a positive feedback loop that enhances FLT4 signaling. Modulates KDR signaling by forming heterodimers. The secreted isoform 3 may function as a decoy receptor for VEGFC and/or VEGFD and play an important role as a negative regulator of VEGFC-mediated lymphangiogenesis and angiogenesis. Binding of vascular growth factors to isoform 1 or isoform 2 leads to the activation of several signaling cascades; isoform 2 seems to be less efficient in signal transduction, because it has a truncated C-terminus and therefore lacks several phosphorylation sites. Mediates activation of the MAPK1/ERK2, MAPK3/ERK1 signaling pathway, of MAPK8 and the JUN signaling pathway, and of the AKT1 signaling pathway. Phosphorylates SHC1. Mediates phosphorylation of PIK3R1, the regulatory subunit of phosphatidylinositol 3-kinase. Promotes phosphorylation of MAPK8 at 'Thr-183' and 'Tyr-185', and of AKT1 at 'Ser-473'","subcellular_location":"Secreted; Cytoplasm","url":"https://www.uniprot.org/uniprotkb/P35916/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/FLT4","classification":"Not Classified","n_dependent_lines":1,"n_total_lines":1208,"dependency_fraction":0.0008278145695364238},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/FLT4","total_profiled":1310},"omim":[{"mim_id":"618780","title":"CONGENITAL HEART DEFECTS, MULTIPLE TYPES, 7; CHTD7","url":"https://www.omim.org/entry/618780"},{"mim_id":"607859","title":"ANGIOMA, TUFTED","url":"https://www.omim.org/entry/607859"},{"mim_id":"602402","title":"FORKHEAD BOX C2; FOXC2","url":"https://www.omim.org/entry/602402"},{"mim_id":"602089","title":"HEMANGIOMA, CAPILLARY INFANTILE","url":"https://www.omim.org/entry/602089"},{"mim_id":"601528","title":"VASCULAR ENDOTHELIAL GROWTH FACTOR C; VEGFC","url":"https://www.omim.org/entry/601528"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Supported","locations":[{"location":"Cytosol","reliability":"Supported"},{"location":"Plasma membrane","reliability":"Additional"},{"location":"Centrosome","reliability":"Additional"}],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in many","driving_tissues":[],"url":"https://www.proteinatlas.org/search/FLT4"},"hgnc":{"alias_symbol":["VEGFR3","PCL","VEGFR-3"],"prev_symbol":[]},"alphafold":{"accession":"P35916","domains":[{"cath_id":"2.60.40.10","chopping":"28-66_78-135","consensus_level":"medium","plddt":86.127,"start":28,"end":135},{"cath_id":"2.60.40.10","chopping":"144-225","consensus_level":"medium","plddt":87.227,"start":144,"end":225},{"cath_id":"2.60.40.10","chopping":"230-329","consensus_level":"high","plddt":87.6299,"start":230,"end":329},{"cath_id":"2.60.40.10","chopping":"350-419","consensus_level":"high","plddt":90.358,"start":350,"end":419},{"cath_id":"2.60.40.10","chopping":"437-466_488-553","consensus_level":"high","plddt":85.3873,"start":437,"end":553},{"cath_id":"2.60.40.10","chopping":"556-674","consensus_level":"high","plddt":79.432,"start":556,"end":674},{"cath_id":"2.60.40.10","chopping":"680-768","consensus_level":"high","plddt":83.4272,"start":680,"end":768},{"cath_id":"3.30.200.20","chopping":"825-929","consensus_level":"high","plddt":79.8323,"start":825,"end":929},{"cath_id":"1.10.510.10","chopping":"936-971_1006-1064_1076-1175","consensus_level":"high","plddt":84.4126,"start":936,"end":1175}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/P35916","model_url":"https://alphafold.ebi.ac.uk/files/AF-P35916-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-P35916-F1-predicted_aligned_error_v6.png","plddt_mean":72.44},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=FLT4","jax_strain_url":"https://www.jax.org/strain/search?query=FLT4"},"sequence":{"accession":"P35916","fasta_url":"https://rest.uniprot.org/uniprotkb/P35916.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/P35916/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/P35916"}},"corpus_meta":[{"pmid":"9435229","id":"PMC_9435229","title":"Vascular endothelial growth factor D (VEGF-D) is a ligand for the tyrosine kinases VEGF receptor 2 (Flk1) and VEGF receptor 3 (Flt4).","date":"1998","source":"Proceedings of the National Academy of Sciences of the United States of America","url":"https://pubmed.ncbi.nlm.nih.gov/9435229","citation_count":991,"is_preprint":false},{"pmid":"18594512","id":"PMC_18594512","title":"Blocking VEGFR-3 suppresses angiogenic sprouting and vascular network formation.","date":"2008","source":"Nature","url":"https://pubmed.ncbi.nlm.nih.gov/18594512","citation_count":658,"is_preprint":false},{"pmid":"10329591","id":"PMC_10329591","title":"VEGFR-3 and its ligand VEGF-C are associated with angiogenesis in breast cancer.","date":"1999","source":"The American journal of pathology","url":"https://pubmed.ncbi.nlm.nih.gov/10329591","citation_count":478,"is_preprint":false},{"pmid":"22426001","id":"PMC_22426001","title":"Notch-dependent VEGFR3 upregulation allows angiogenesis without VEGF-VEGFR2 signalling.","date":"2012","source":"Nature","url":"https://pubmed.ncbi.nlm.nih.gov/22426001","citation_count":304,"is_preprint":false},{"pmid":"12393704","id":"PMC_12393704","title":"VEGFR-3 and CD133 identify a population of CD34+ lymphatic/vascular endothelial precursor cells.","date":"2002","source":"Blood","url":"https://pubmed.ncbi.nlm.nih.gov/12393704","citation_count":293,"is_preprint":false},{"pmid":"20949568","id":"PMC_20949568","title":"Consistent MYC and FLT4 gene amplification in radiation-induced angiosarcoma but not in other radiation-associated atypical vascular lesions.","date":"2011","source":"Genes, chromosomes & cancer","url":"https://pubmed.ncbi.nlm.nih.gov/20949568","citation_count":257,"is_preprint":false},{"pmid":"1327515","id":"PMC_1327515","title":"FLT4 receptor tyrosine kinase contains seven immunoglobulin-like loops and is expressed in multiple human tissues and cell lines.","date":"1992","source":"Cancer research","url":"https://pubmed.ncbi.nlm.nih.gov/1327515","citation_count":247,"is_preprint":false},{"pmid":"17164762","id":"PMC_17164762","title":"The role of the VEGF-C/VEGFR-3 axis in cancer progression.","date":"2006","source":"British journal of cancer","url":"https://pubmed.ncbi.nlm.nih.gov/17164762","citation_count":222,"is_preprint":false},{"pmid":"8245783","id":"PMC_8245783","title":"The related FLT4, FLT1, and KDR receptor tyrosine kinases show distinct expression patterns in human fetal endothelial cells.","date":"1993","source":"The Journal of experimental medicine","url":"https://pubmed.ncbi.nlm.nih.gov/8245783","citation_count":220,"is_preprint":false},{"pmid":"19906867","id":"PMC_19906867","title":"Vegfc/Flt4 signalling is suppressed by Dll4 in developing zebrafish intersegmental arteries.","date":"2009","source":"Development (Cambridge, England)","url":"https://pubmed.ncbi.nlm.nih.gov/19906867","citation_count":197,"is_preprint":false},{"pmid":"26735859","id":"PMC_26735859","title":"Recurrent CIC Gene Abnormalities in Angiosarcomas: A Molecular Study of 120 Cases With Concurrent Investigation of PLCG1, KDR, MYC, and FLT4 Gene Alterations.","date":"2016","source":"The American journal of surgical pathology","url":"https://pubmed.ncbi.nlm.nih.gov/26735859","citation_count":165,"is_preprint":false},{"pmid":"25229256","id":"PMC_25229256","title":"TNFR1 mediates TNF-α-induced tumour lymphangiogenesis and metastasis by modulating VEGF-C-VEGFR3 signalling.","date":"2014","source":"Nature communications","url":"https://pubmed.ncbi.nlm.nih.gov/25229256","citation_count":158,"is_preprint":false},{"pmid":"8386825","id":"PMC_8386825","title":"The FLT4 gene encodes a transmembrane tyrosine kinase related to the vascular endothelial growth factor receptor.","date":"1993","source":"Oncogene","url":"https://pubmed.ncbi.nlm.nih.gov/8386825","citation_count":149,"is_preprint":false},{"pmid":"11745682","id":"PMC_11745682","title":"VEGFR-3 in adult angiogenesis.","date":"2001","source":"The Journal of pathology","url":"https://pubmed.ncbi.nlm.nih.gov/11745682","citation_count":133,"is_preprint":false},{"pmid":"7970715","id":"PMC_7970715","title":"Signalling properties of FLT4, a proteolytically processed receptor tyrosine kinase related to two VEGF receptors.","date":"1994","source":"Oncogene","url":"https://pubmed.ncbi.nlm.nih.gov/7970715","citation_count":130,"is_preprint":false},{"pmid":"28298294","id":"PMC_28298294","title":"VEGFR3 Modulates Vascular Permeability by Controlling VEGF/VEGFR2 Signaling.","date":"2017","source":"Circulation research","url":"https://pubmed.ncbi.nlm.nih.gov/28298294","citation_count":123,"is_preprint":false},{"pmid":"15689446","id":"PMC_15689446","title":"Milroy disease and the VEGFR-3 mutation phenotype.","date":"2005","source":"Journal of medical genetics","url":"https://pubmed.ncbi.nlm.nih.gov/15689446","citation_count":121,"is_preprint":false},{"pmid":"17210781","id":"PMC_17210781","title":"Cooperative and redundant roles of VEGFR-2 and VEGFR-3 signaling in adult lymphangiogenesis.","date":"2007","source":"FASEB journal : official publication of the Federation of American Societies for Experimental Biology","url":"https://pubmed.ncbi.nlm.nih.gov/17210781","citation_count":119,"is_preprint":false},{"pmid":"11090062","id":"PMC_11090062","title":"VEGF-C signaling pathways through VEGFR-2 and VEGFR-3 in vasculoangiogenesis and hematopoiesis.","date":"2000","source":"Blood","url":"https://pubmed.ncbi.nlm.nih.gov/11090062","citation_count":117,"is_preprint":false},{"pmid":"20697430","id":"PMC_20697430","title":"VEGFR-3 ligand-binding and kinase activity are required for lymphangiogenesis but not for angiogenesis.","date":"2010","source":"Cell research","url":"https://pubmed.ncbi.nlm.nih.gov/20697430","citation_count":116,"is_preprint":false},{"pmid":"12819011","id":"PMC_12819011","title":"Novel expression of vascular endothelial growth factor receptor (VEGFR)-3 and VEGF-C on corneal dendritic cells.","date":"2003","source":"The American journal of pathology","url":"https://pubmed.ncbi.nlm.nih.gov/12819011","citation_count":116,"is_preprint":false},{"pmid":"25524775","id":"PMC_25524775","title":"Molecular controls of lymphatic VEGFR3 signaling.","date":"2014","source":"Arteriosclerosis, thrombosis, and vascular biology","url":"https://pubmed.ncbi.nlm.nih.gov/25524775","citation_count":114,"is_preprint":false},{"pmid":"1310071","id":"PMC_1310071","title":"FLT4, a novel class III receptor tyrosine kinase in chromosome 5q33-qter.","date":"1992","source":"Cancer research","url":"https://pubmed.ncbi.nlm.nih.gov/1310071","citation_count":109,"is_preprint":false},{"pmid":"25561555","id":"PMC_25561555","title":"VEGFR3 does not sustain retinal angiogenesis without VEGFR2.","date":"2015","source":"Proceedings of the National Academy of Sciences of the United States of America","url":"https://pubmed.ncbi.nlm.nih.gov/25561555","citation_count":103,"is_preprint":false},{"pmid":"27783948","id":"PMC_27783948","title":"Macrophage-Induced Lymphangiogenesis and Metastasis following Paclitaxel Chemotherapy Is Regulated by VEGFR3.","date":"2016","source":"Cell reports","url":"https://pubmed.ncbi.nlm.nih.gov/27783948","citation_count":101,"is_preprint":false},{"pmid":"34323412","id":"PMC_34323412","title":"Tumor-derived exosomal BCYRN1 activates WNT5A/VEGF-C/VEGFR3 feedforward loop to drive lymphatic metastasis of bladder cancer.","date":"2021","source":"Clinical and translational medicine","url":"https://pubmed.ncbi.nlm.nih.gov/34323412","citation_count":95,"is_preprint":false},{"pmid":"22007135","id":"PMC_22007135","title":"Rspo1/Wnt signaling promotes angiogenesis via Vegfc/Vegfr3.","date":"2011","source":"Development (Cambridge, England)","url":"https://pubmed.ncbi.nlm.nih.gov/22007135","citation_count":92,"is_preprint":false},{"pmid":"9264375","id":"PMC_9264375","title":"Expression of FLT4 and its ligand VEGF-C in acute myeloid leukemia.","date":"1997","source":"Leukemia","url":"https://pubmed.ncbi.nlm.nih.gov/9264375","citation_count":84,"is_preprint":false},{"pmid":"7692369","id":"PMC_7692369","title":"Two human FLT4 receptor tyrosine kinase isoforms with distinct carboxy terminal tails are produced by alternative processing of primary transcripts.","date":"1993","source":"Oncogene","url":"https://pubmed.ncbi.nlm.nih.gov/7692369","citation_count":81,"is_preprint":false},{"pmid":"35763346","id":"PMC_35763346","title":"Lymphangiogenesis requires Ang2/Tie/PI3K signaling for VEGFR3 cell-surface expression.","date":"2022","source":"The Journal of clinical investigation","url":"https://pubmed.ncbi.nlm.nih.gov/35763346","citation_count":80,"is_preprint":false},{"pmid":"22584122","id":"PMC_22584122","title":"SAR131675, a potent and selective VEGFR-3-TK inhibitor with antilymphangiogenic, antitumoral, and antimetastatic activities.","date":"2012","source":"Molecular cancer therapeutics","url":"https://pubmed.ncbi.nlm.nih.gov/22584122","citation_count":76,"is_preprint":false},{"pmid":"31239267","id":"PMC_31239267","title":"Activation of the VEGFC/VEGFR3 Pathway Induces Tumor Immune Escape in Colorectal Cancer.","date":"2019","source":"Cancer research","url":"https://pubmed.ncbi.nlm.nih.gov/31239267","citation_count":73,"is_preprint":false},{"pmid":"1319394","id":"PMC_1319394","title":"Chromosomal localization of FLT4, a novel receptor-type tyrosine kinase gene.","date":"1992","source":"Genomics","url":"https://pubmed.ncbi.nlm.nih.gov/1319394","citation_count":70,"is_preprint":false},{"pmid":"16523449","id":"PMC_16523449","title":"Expression and localization of VEGF-C and VEGFR-3 in glioblastomas and haemangioblastomas.","date":"2006","source":"The Journal of pathology","url":"https://pubmed.ncbi.nlm.nih.gov/16523449","citation_count":67,"is_preprint":false},{"pmid":"33783987","id":"PMC_33783987","title":"VEGF-C/VEGFR-3 axis protects against pressure-overload induced cardiac dysfunction through regulation of lymphangiogenesis.","date":"2021","source":"Clinical and translational medicine","url":"https://pubmed.ncbi.nlm.nih.gov/33783987","citation_count":67,"is_preprint":false},{"pmid":"20439995","id":"PMC_20439995","title":"Tbx1 regulates Vegfr3 and is required for lymphatic vessel development.","date":"2010","source":"The Journal of cell biology","url":"https://pubmed.ncbi.nlm.nih.gov/20439995","citation_count":65,"is_preprint":false},{"pmid":"34632918","id":"PMC_34632918","title":"FLT4/VEGFR3 activates AMPK to coordinate glycometabolic reprogramming with autophagy and inflammasome activation for bacterial elimination.","date":"2021","source":"Autophagy","url":"https://pubmed.ncbi.nlm.nih.gov/34632918","citation_count":62,"is_preprint":false},{"pmid":"23074044","id":"PMC_23074044","title":"FLT4/VEGFR3 and Milroy disease: novel mutations, a review of published variants and database update.","date":"2012","source":"Human mutation","url":"https://pubmed.ncbi.nlm.nih.gov/23074044","citation_count":61,"is_preprint":false},{"pmid":"11292664","id":"PMC_11292664","title":"VEGFR3 gene structure, regulatory region, and sequence polymorphisms.","date":"2001","source":"FASEB journal : official publication of the Federation of American Societies for Experimental Biology","url":"https://pubmed.ncbi.nlm.nih.gov/11292664","citation_count":61,"is_preprint":false},{"pmid":"29615616","id":"PMC_29615616","title":"Heterogeneity in VEGFR3 levels drives lymphatic vessel hyperplasia through cell-autonomous and non-cell-autonomous mechanisms.","date":"2018","source":"Nature communications","url":"https://pubmed.ncbi.nlm.nih.gov/29615616","citation_count":55,"is_preprint":false},{"pmid":"30102256","id":"PMC_30102256","title":"Epsin deficiency promotes lymphangiogenesis through regulation of VEGFR3 degradation in diabetes.","date":"2018","source":"The Journal of clinical investigation","url":"https://pubmed.ncbi.nlm.nih.gov/30102256","citation_count":54,"is_preprint":false},{"pmid":"19289394","id":"PMC_19289394","title":"Recessive primary congenital lymphoedema caused by a VEGFR3 mutation.","date":"2009","source":"Journal of medical genetics","url":"https://pubmed.ncbi.nlm.nih.gov/19289394","citation_count":53,"is_preprint":false},{"pmid":"22223733","id":"PMC_22223733","title":"Mirtron microRNA-1236 inhibits VEGFR-3 signaling during inflammatory lymphangiogenesis.","date":"2012","source":"Arteriosclerosis, thrombosis, and vascular biology","url":"https://pubmed.ncbi.nlm.nih.gov/22223733","citation_count":50,"is_preprint":false},{"pmid":"18292935","id":"PMC_18292935","title":"Hypoxia-induced epithelial VEGF-C/VEGFR-3 upregulation in carcinoma cell lines.","date":"2008","source":"International journal of oncology","url":"https://pubmed.ncbi.nlm.nih.gov/18292935","citation_count":49,"is_preprint":false},{"pmid":"27527412","id":"PMC_27527412","title":"Pathway-related molecules of VEGFC/D-VEGFR3/NRP2 axis in tumor lymphangiogenesis and lymphatic metastasis.","date":"2016","source":"Clinica chimica acta; international journal of clinical chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/27527412","citation_count":48,"is_preprint":false},{"pmid":"14760756","id":"PMC_14760756","title":"Expression and significance of VEGF-C and FLT-4 in gastric cancer.","date":"2004","source":"World journal of gastroenterology","url":"https://pubmed.ncbi.nlm.nih.gov/14760756","citation_count":48,"is_preprint":false},{"pmid":"19706680","id":"PMC_19706680","title":"Sumoylation of Prox1 controls its ability to induce VEGFR3 expression and lymphatic phenotypes in endothelial cells.","date":"2009","source":"Journal of cell science","url":"https://pubmed.ncbi.nlm.nih.gov/19706680","citation_count":48,"is_preprint":false},{"pmid":"26993803","id":"PMC_26993803","title":"Vegfr3-CreER (T2) mouse, a new genetic tool for targeting the lymphatic system.","date":"2016","source":"Angiogenesis","url":"https://pubmed.ncbi.nlm.nih.gov/26993803","citation_count":48,"is_preprint":false},{"pmid":"34446463","id":"PMC_34446463","title":"VEGF-C/VEGFR-3 signalling in macrophages ameliorates acute lung injury.","date":"2022","source":"The European respiratory journal","url":"https://pubmed.ncbi.nlm.nih.gov/34446463","citation_count":47,"is_preprint":false},{"pmid":"17115285","id":"PMC_17115285","title":"Expression of VEGFR3 in glioma endothelium correlates with tumor grade.","date":"2006","source":"Journal of neuro-oncology","url":"https://pubmed.ncbi.nlm.nih.gov/17115285","citation_count":46,"is_preprint":false},{"pmid":"17584927","id":"PMC_17584927","title":"Elevated expression of VEGFR-3 in lymphatic endothelial cells from lymphangiomas.","date":"2007","source":"BMC cancer","url":"https://pubmed.ncbi.nlm.nih.gov/17584927","citation_count":45,"is_preprint":false},{"pmid":"12393458","id":"PMC_12393458","title":"Modulation of VEGFR-2-mediated endothelial-cell activity by VEGF-C/VEGFR-3.","date":"2002","source":"Blood","url":"https://pubmed.ncbi.nlm.nih.gov/12393458","citation_count":45,"is_preprint":false},{"pmid":"37058549","id":"PMC_37058549","title":"Blockade of VEGFR3 signaling leads to functional impairment of dural lymphatic vessels without affecting autoimmune neuroinflammation.","date":"2023","source":"Science immunology","url":"https://pubmed.ncbi.nlm.nih.gov/37058549","citation_count":44,"is_preprint":false},{"pmid":"33067626","id":"PMC_33067626","title":"The physiological and pathological functions of VEGFR3 in cardiac and lymphatic development and related diseases.","date":"2021","source":"Cardiovascular research","url":"https://pubmed.ncbi.nlm.nih.gov/33067626","citation_count":44,"is_preprint":false},{"pmid":"30518533","id":"PMC_30518533","title":"Identification of ILK as a critical regulator of VEGFR3 signalling and lymphatic vascular growth.","date":"2018","source":"The EMBO journal","url":"https://pubmed.ncbi.nlm.nih.gov/30518533","citation_count":44,"is_preprint":false},{"pmid":"11332691","id":"PMC_11332691","title":"Expression of VEGF-C and activation of its receptors VEGFR-2 and VEGFR-3 in trophoblast.","date":"2001","source":"Histology and histopathology","url":"https://pubmed.ncbi.nlm.nih.gov/11332691","citation_count":44,"is_preprint":false},{"pmid":"25605009","id":"PMC_25605009","title":"Genistein suppresses FLT4 and inhibits human colorectal cancer metastasis.","date":"2015","source":"Oncotarget","url":"https://pubmed.ncbi.nlm.nih.gov/25605009","citation_count":43,"is_preprint":false},{"pmid":"25973301","id":"PMC_25973301","title":"VEGF-C-VEGFR3/Flt4 axis regulates mammary tumor growth and metastasis in an autocrine manner.","date":"2015","source":"American journal of cancer research","url":"https://pubmed.ncbi.nlm.nih.gov/25973301","citation_count":42,"is_preprint":false},{"pmid":"7898938","id":"PMC_7898938","title":"Biochemical characterization of two isoforms of FLT4, a VEGF receptor-related tyrosine kinase.","date":"1995","source":"Oncogene","url":"https://pubmed.ncbi.nlm.nih.gov/7898938","citation_count":42,"is_preprint":false},{"pmid":"27789478","id":"PMC_27789478","title":"MicroRNA-126a Directs Lymphangiogenesis Through Interacting With Chemokine and Flt4 Signaling in Zebrafish.","date":"2016","source":"Arteriosclerosis, thrombosis, and vascular biology","url":"https://pubmed.ncbi.nlm.nih.gov/27789478","citation_count":42,"is_preprint":false},{"pmid":"38201272","id":"PMC_38201272","title":"Dysregulation of Lymphatic Endothelial VEGFR3 Signaling in Disease.","date":"2023","source":"Cells","url":"https://pubmed.ncbi.nlm.nih.gov/38201272","citation_count":41,"is_preprint":false},{"pmid":"24845798","id":"PMC_24845798","title":"Expression profiling and significance of VEGF-A, VEGFR2, VEGFR3 and related proteins in endometrial carcinoma.","date":"2014","source":"Cytokine","url":"https://pubmed.ncbi.nlm.nih.gov/24845798","citation_count":41,"is_preprint":false},{"pmid":"29169284","id":"PMC_29169284","title":"VEGFC/VEGFR3 Signaling Regulates Mouse Spermatogonial Cell Proliferation via the Activation of AKT/MAPK and Cyclin D1 Pathway and Mediates the Apoptosis by affecting Caspase 3/9 and Bcl-2.","date":"2018","source":"Cell cycle (Georgetown, Tex.)","url":"https://pubmed.ncbi.nlm.nih.gov/29169284","citation_count":41,"is_preprint":false},{"pmid":"34133928","id":"PMC_34133928","title":"VEGFC/FLT4-induced cell-cycle arrest mediates sprouting and differentiation of venous and lymphatic endothelial cells.","date":"2021","source":"Cell reports","url":"https://pubmed.ncbi.nlm.nih.gov/34133928","citation_count":40,"is_preprint":false},{"pmid":"10728593","id":"PMC_10728593","title":"VEGFc and VEGFR3 expression in human thyroid pathologies.","date":"2000","source":"International journal of cancer","url":"https://pubmed.ncbi.nlm.nih.gov/10728593","citation_count":40,"is_preprint":false},{"pmid":"27901498","id":"PMC_27901498","title":"Targeting the VEGF-C/VEGFR3 axis suppresses Slug-mediated cancer metastasis and stemness via inhibition of KRAS/YAP1 signaling.","date":"2017","source":"Oncotarget","url":"https://pubmed.ncbi.nlm.nih.gov/27901498","citation_count":39,"is_preprint":false},{"pmid":"33931446","id":"PMC_33931446","title":"Mitochondrial respiration controls the Prox1-Vegfr3 feedback loop during lymphatic endothelial cell fate specification and maintenance.","date":"2021","source":"Science advances","url":"https://pubmed.ncbi.nlm.nih.gov/33931446","citation_count":38,"is_preprint":false},{"pmid":"21617236","id":"PMC_21617236","title":"Lymphatic microvessel density, VEGF-C, and VEGFR-3 expression in different molecular types of breast cancer.","date":"2011","source":"Anticancer research","url":"https://pubmed.ncbi.nlm.nih.gov/21617236","citation_count":35,"is_preprint":false},{"pmid":"25864386","id":"PMC_25864386","title":"The utility of MYC and FLT4 in the diagnosis and treatment of postradiation atypical vascular lesion and angiosarcoma of the breast.","date":"2015","source":"Human pathology","url":"https://pubmed.ncbi.nlm.nih.gov/25864386","citation_count":35,"is_preprint":false},{"pmid":"17458866","id":"PMC_17458866","title":"A novel VEGFR3 mutation causes Milroy disease.","date":"2007","source":"American journal of medical genetics. Part A","url":"https://pubmed.ncbi.nlm.nih.gov/17458866","citation_count":35,"is_preprint":false},{"pmid":"9247316","id":"PMC_9247316","title":"Characterization of murine Flt4 ligand/VEGF-C.","date":"1997","source":"Oncogene","url":"https://pubmed.ncbi.nlm.nih.gov/9247316","citation_count":35,"is_preprint":false},{"pmid":"28629427","id":"PMC_28629427","title":"Targeting VEGFR-3/-2 signaling pathways with AD0157: a potential strategy against tumor-associated lymphangiogenesis and lymphatic metastases.","date":"2017","source":"Journal of hematology & oncology","url":"https://pubmed.ncbi.nlm.nih.gov/28629427","citation_count":34,"is_preprint":false},{"pmid":"22251800","id":"PMC_22251800","title":"DNA methylation regulates expression of VEGF-R2 (KDR) and VEGF-R3 (FLT4).","date":"2012","source":"BMC cancer","url":"https://pubmed.ncbi.nlm.nih.gov/22251800","citation_count":32,"is_preprint":false},{"pmid":"34351741","id":"PMC_34351741","title":"Discovery, Synthesis, and Evaluation of Highly Selective Vascular Endothelial Growth Factor Receptor 3 (VEGFR3) Inhibitor for the Potential Treatment of Metastatic Triple-Negative Breast Cancer.","date":"2021","source":"Journal of medicinal chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/34351741","citation_count":32,"is_preprint":false},{"pmid":"24252749","id":"PMC_24252749","title":"The VEGF-C/VEGFR3 signaling pathway contributes to resolving chronic skin inflammation by activating lymphatic vessel function.","date":"2013","source":"Journal of dermatological science","url":"https://pubmed.ncbi.nlm.nih.gov/24252749","citation_count":32,"is_preprint":false},{"pmid":"21839498","id":"PMC_21839498","title":"Suppression of vascular endothelial growth factor receptor 3 (VEGFR3) and vascular endothelial growth factor C (VEGFC) inhibits hypoxia-induced lymph node metastases in cervix cancer.","date":"2011","source":"Gynecologic oncology","url":"https://pubmed.ncbi.nlm.nih.gov/21839498","citation_count":32,"is_preprint":false},{"pmid":"24708522","id":"PMC_24708522","title":"Slit2N and Robo4 regulate lymphangiogenesis through the VEGF-C/VEGFR-3 pathway.","date":"2014","source":"Cell communication and signaling : CCS","url":"https://pubmed.ncbi.nlm.nih.gov/24708522","citation_count":31,"is_preprint":false},{"pmid":"25003676","id":"PMC_25003676","title":"Roles of serum and biliary CEA, CA19-9, VEGFR3, and TAC in differentiating between malignant and benign biliary obstructions.","date":"2014","source":"The Turkish journal of gastroenterology : the official journal of Turkish Society of Gastroenterology","url":"https://pubmed.ncbi.nlm.nih.gov/25003676","citation_count":31,"is_preprint":false},{"pmid":"36064450","id":"PMC_36064450","title":"ADSCs stimulated by VEGF-C alleviate intestinal inflammation via dual mechanisms of enhancing lymphatic drainage by a VEGF-C/VEGFR-3-dependent mechanism and inhibiting the NF-κB pathway by the secretome.","date":"2022","source":"Stem cell research & therapy","url":"https://pubmed.ncbi.nlm.nih.gov/36064450","citation_count":31,"is_preprint":false},{"pmid":"27991863","id":"PMC_27991863","title":"Carbohydrate-binding protein CLEC14A regulates VEGFR-2- and VEGFR-3-dependent signals during angiogenesis and lymphangiogenesis.","date":"2016","source":"The Journal of clinical investigation","url":"https://pubmed.ncbi.nlm.nih.gov/27991863","citation_count":30,"is_preprint":false},{"pmid":"26064438","id":"PMC_26064438","title":"VEGF-C/VEGFR-3 pathway promotes myocyte hypertrophy and survival in the infarcted myocardium.","date":"2015","source":"American journal of translational research","url":"https://pubmed.ncbi.nlm.nih.gov/26064438","citation_count":29,"is_preprint":false},{"pmid":"30618798","id":"PMC_30618798","title":"VEGFR-3 Signaling Regulates Triglyceride Retention and Absorption in the Intestine.","date":"2018","source":"Frontiers in physiology","url":"https://pubmed.ncbi.nlm.nih.gov/30618798","citation_count":28,"is_preprint":false},{"pmid":"28850122","id":"PMC_28850122","title":"Distinct transcriptional responses of lymphatic endothelial cells to VEGFR-3 and VEGFR-2 stimulation.","date":"2017","source":"Scientific data","url":"https://pubmed.ncbi.nlm.nih.gov/28850122","citation_count":28,"is_preprint":false},{"pmid":"27464987","id":"PMC_27464987","title":"Regulation of lymphangiogenesis in the diaphragm by macrophages and VEGFR-3 signaling.","date":"2016","source":"Angiogenesis","url":"https://pubmed.ncbi.nlm.nih.gov/27464987","citation_count":27,"is_preprint":false},{"pmid":"30385613","id":"PMC_30385613","title":"Genetic Variants of VEGFA and FLT4 Are Determinants of Survival in Renal Cell Carcinoma Patients Treated with Sorafenib.","date":"2018","source":"Cancer research","url":"https://pubmed.ncbi.nlm.nih.gov/30385613","citation_count":26,"is_preprint":false},{"pmid":"32668254","id":"PMC_32668254","title":"Antagonistic Activities of Vegfr3/Flt4 and Notch1b Fine-tune Mechanosensitive Signaling during Zebrafish Cardiac Valvulogenesis.","date":"2020","source":"Cell reports","url":"https://pubmed.ncbi.nlm.nih.gov/32668254","citation_count":25,"is_preprint":false},{"pmid":"25157650","id":"PMC_25157650","title":"Restoration of natural killer cell cytotoxicity by VEGFR-3 inhibition in myelogenous leukemia.","date":"2014","source":"Cancer letters","url":"https://pubmed.ncbi.nlm.nih.gov/25157650","citation_count":25,"is_preprint":false},{"pmid":"25003617","id":"PMC_25003617","title":"Novel peptides suppress VEGFR-3 activity and antagonize VEGFR-3-mediated oncogenic effects.","date":"2014","source":"Oncotarget","url":"https://pubmed.ncbi.nlm.nih.gov/25003617","citation_count":23,"is_preprint":false},{"pmid":"17926187","id":"PMC_17926187","title":"Expression of VEGF-C, VEGF-D and their receptor VEGFR-3 in diffuse large B-cell lymphomas.","date":"2007","source":"Leukemia & lymphoma","url":"https://pubmed.ncbi.nlm.nih.gov/17926187","citation_count":23,"is_preprint":false},{"pmid":"37454290","id":"PMC_37454290","title":"VEGFR3 is required for button junction formation in lymphatic vessels.","date":"2023","source":"Cell reports","url":"https://pubmed.ncbi.nlm.nih.gov/37454290","citation_count":22,"is_preprint":false},{"pmid":"34551997","id":"PMC_34551997","title":"Heterozygous Mutation of Vegfr3 Reduces Renal Lymphatics without Renal Dysfunction.","date":"2021","source":"Journal of the American Society of Nephrology : JASN","url":"https://pubmed.ncbi.nlm.nih.gov/34551997","citation_count":22,"is_preprint":false},{"pmid":"30518756","id":"PMC_30518756","title":"uPARAP/Endo180 receptor is a gatekeeper of VEGFR-2/VEGFR-3 heterodimerisation during pathological lymphangiogenesis.","date":"2018","source":"Nature communications","url":"https://pubmed.ncbi.nlm.nih.gov/30518756","citation_count":22,"is_preprint":false},{"pmid":"24036251","id":"PMC_24036251","title":"VEGFR-3 neutralization inhibits ovarian lymphangiogenesis, follicle maturation, and murine pregnancy.","date":"2013","source":"The American journal of pathology","url":"https://pubmed.ncbi.nlm.nih.gov/24036251","citation_count":22,"is_preprint":false},{"pmid":"33578235","id":"PMC_33578235","title":"Qingjie Fuzheng Granule suppresses lymphangiogenesis in colorectal cancer via the VEGF-C/VEGFR-3 dependent PI3K/AKT pathway.","date":"2021","source":"Biomedicine & pharmacotherapy = Biomedecine & pharmacotherapie","url":"https://pubmed.ncbi.nlm.nih.gov/33578235","citation_count":22,"is_preprint":false},{"pmid":"9345034","id":"PMC_9345034","title":"Signal transduction in human hematopoietic cells by vascular endothelial growth factor related protein, a novel ligand for the FLT4 receptor.","date":"1997","source":"Blood","url":"https://pubmed.ncbi.nlm.nih.gov/9345034","citation_count":22,"is_preprint":false},{"pmid":"23404187","id":"PMC_23404187","title":"A VEGFR-3 antagonist increases IFN-γ expression on low functioning NK cells in acute myeloid leukemia.","date":"2013","source":"Journal of clinical immunology","url":"https://pubmed.ncbi.nlm.nih.gov/23404187","citation_count":21,"is_preprint":false},{"pmid":"23868727","id":"PMC_23868727","title":"Inhibition of FAK and VEGFR-3 binding decreases tumorigenicity in neuroblastoma.","date":"2013","source":"Molecular carcinogenesis","url":"https://pubmed.ncbi.nlm.nih.gov/23868727","citation_count":20,"is_preprint":false},{"pmid":"34232612","id":"PMC_34232612","title":"Surface Engineering of FLT4-Targeted Nanocarriers Enhances Cell-Softening Glaucoma Therapy.","date":"2021","source":"ACS applied materials & interfaces","url":"https://pubmed.ncbi.nlm.nih.gov/34232612","citation_count":20,"is_preprint":false},{"pmid":"19900702","id":"PMC_19900702","title":"Inhibiton of RET and JAK2 signals and upregulation of VEGFR3 phosphorylation in vitro by galectin-1 in trophoblast tumor cells BeWo.","date":"2009","source":"Placenta","url":"https://pubmed.ncbi.nlm.nih.gov/19900702","citation_count":19,"is_preprint":false},{"pmid":"37167063","id":"PMC_37167063","title":"VEGFR-3 signaling restrains the neuron-macrophage crosstalk during neurotropic viral infection.","date":"2023","source":"Cell reports","url":"https://pubmed.ncbi.nlm.nih.gov/37167063","citation_count":18,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":54310,"output_tokens":9260,"usd":0.150915,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":19286,"output_tokens":6748,"usd":0.132565,"stage2_stop_reason":"end_turn"},"total_usd":0.28348,"stage1_batch_id":"msgbatch_01AsR7g8dGTEiEw9U83bJeWn","stage2_batch_id":"msgbatch_01YV5ZyxtFNUZEjxRcpd9jzb","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 1992,\n      \"finding\": \"FLT4 encodes a transmembrane receptor tyrosine kinase with seven immunoglobulin-like loops in its extracellular domain, structurally related to FLT1 and KDR/FLK1, constituting a subfamily of class III tyrosine kinases.\",\n      \"method\": \"cDNA cloning, sequencing, structural analysis\",\n      \"journal\": \"Cancer research\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — full-length cDNA sequenced and protein structure determined; replicated by independent lab in same year (PMID:8386825)\",\n      \"pmids\": [\"1327515\", \"8386825\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1992,\n      \"finding\": \"FLT4 gene maps to chromosomal region 5q33-qter (human) and chromosome 11 (mouse).\",\n      \"method\": \"Chromosomal mapping, genomic analysis\",\n      \"journal\": \"Cancer research / Genomics\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — replicated by two independent labs in same year\",\n      \"pmids\": [\"1310071\", \"1319394\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1993,\n      \"finding\": \"FLT4 protein is expressed as a ~170 kDa glycoprotein when transiently expressed in Cos-7 cells, as shown by immunoprecipitation with FLT4-specific antisera.\",\n      \"method\": \"Transient expression in Cos-7 cells, immunoprecipitation, Western blot\",\n      \"journal\": \"Oncogene\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — direct biochemical characterization, single lab\",\n      \"pmids\": [\"8386825\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1993,\n      \"finding\": \"FLT4 is expressed in vascular endothelial cells of developing vessels in multiple fetal organs, with overlapping but distinct expression patterns compared to FLT1 and KDR/FLK1.\",\n      \"method\": \"Northern blot, in situ hybridization in human fetal tissues\",\n      \"journal\": \"The Journal of experimental medicine\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — direct localization by in situ hybridization, single lab, multiple tissues\",\n      \"pmids\": [\"8245783\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1993,\n      \"finding\": \"Two FLT4 isoforms (short and long) are generated by alternative polyadenylation and subsequent alternative splicing, producing proteins differing in their C-terminal tails.\",\n      \"method\": \"cDNA cloning, genomic structure analysis, Northern blot\",\n      \"journal\": \"Oncogene\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — molecular cloning plus genomic structure determination, replicated biochemically\",\n      \"pmids\": [\"7692369\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1994,\n      \"finding\": \"FLT4 does not bind VEGF and does not undergo autophosphorylation in response to VEGF. When its tyrosine kinase domain was activated via a CSF-1R/FLT4 chimera, FLT4 kinase interacted with SHC and GRB2 adaptor proteins via their SH2 domains in vitro and with SHC in cells, and stimulated thymidine incorporation in NIH3T3 fibroblasts but not in endothelial cells.\",\n      \"method\": \"Receptor chimera assay, SH2 domain binding assay, autophosphorylation assay, thymidine incorporation\",\n      \"journal\": \"Oncogene\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — in vitro reconstitution with chimeric receptor, mutagenesis-equivalent domain swapping, multiple orthogonal assays in single study\",\n      \"pmids\": [\"7970715\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1995,\n      \"finding\": \"The long isoform of FLT4 (FF4L), but not the short isoform (FF4S), can induce anchorage-independent growth of Rat-2 cells in soft agar upon CSF-1 stimulation of CSF-1R/FLT4 chimeras, demonstrating functional differences between the two isoforms. Both isoforms are highly glycosylated (~180 kDa) cell-surface kinases.\",\n      \"method\": \"Soft agar colony assay, CSF-1R/FLT4 chimeric receptor expression, biochemical characterization\",\n      \"journal\": \"Oncogene\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — functional assay distinguishing isoforms, single lab with multiple methods\",\n      \"pmids\": [\"7898938\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1997,\n      \"finding\": \"VEGF-C (Flt4 ligand/VRP) is the cognate ligand for FLT4; recombinant VEGF-C activates FLT4 as demonstrated by induction of tyrosyl phosphorylation and stimulates mitogenesis of lymphatic endothelial cells. VEGF-C is proteolytically processed to generate a mature ~21 kDa homodimer.\",\n      \"method\": \"BIAcore binding assay, receptor affinity chromatography, tyrosyl phosphorylation assay, mitogenesis assay\",\n      \"journal\": \"Oncogene\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — ligand identified by affinity purification, receptor activation confirmed by phosphorylation assay, functional mitogenesis demonstrated; replicated by independent groups\",\n      \"pmids\": [\"9247316\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1997,\n      \"finding\": \"VRP/VEGF-C stimulation of FLT4 in hematopoietic HEL cells induces formation of a signaling complex including Shc, Grb2, and SOS at the activated receptor, activates RAFTK (focal adhesion kinase family member) and its association with Grb2, activates JNK, and induces paxillin phosphorylation.\",\n      \"method\": \"Co-immunoprecipitation, kinase assay, Western blot for phosphorylation\",\n      \"journal\": \"Blood\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple co-IP and phosphorylation assays, single lab\",\n      \"pmids\": [\"9345034\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1998,\n      \"finding\": \"VEGF-D is a ligand for both VEGFR-2 (Flk1) and VEGFR-3 (Flt4) and can activate these receptors; the receptor-binding capacity resides in the VEGF-homology domain (mature form). VEGF-D does not bind VEGFR-1.\",\n      \"method\": \"Receptor-binding assays, receptor activation assays, deletion mutant analysis\",\n      \"journal\": \"Proceedings of the National Academy of Sciences\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — direct receptor-binding and activation assays with deletion constructs, published in high-impact journal with extensive citations\",\n      \"pmids\": [\"9435229\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2000,\n      \"finding\": \"VEGF-C signaling through VEGFR-3 regulates VEGFR-2 signaling: in VEGFR-3-deficient embryos, excess VEGF-C signals through VEGFR-2, causing disturbed vasculogenesis and suppressed hematopoiesis. VEGFR-3 binding of VEGF-C limits the amount available for VEGFR-2 activation.\",\n      \"method\": \"P-Sp/OP9 coculture, VEGFR-3-deficient mouse embryos, soluble receptor competitor assays\",\n      \"journal\": \"Blood\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — genetic KO combined with ligand competition experiments in embryonic culture model, multiple orthogonal approaches\",\n      \"pmids\": [\"11090062\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2001,\n      \"finding\": \"VEGFR-3 promoter contains TATA-less proximal sequences with endothelial cell-specific transcriptional activity in transfection assays; a 1.6 kb promoter fragment directed weak lymphatic endothelial expression of LacZ in transgenic mice.\",\n      \"method\": \"Reporter gene transfection, transgenic mouse analysis\",\n      \"journal\": \"FASEB journal\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — in vitro and in vivo promoter activity assays, single lab\",\n      \"pmids\": [\"11292664\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2002,\n      \"finding\": \"VEGF-C/VEGFR-3 signaling negatively modulates VEGFR-2 activity in endothelial cells: an antagonistic VEGFR-3 antibody (AFL4) induced VEGF-A-dependent EC dispersion similar to VEGFR-2 activation, suggesting VEGFR-3 suppresses VEGFR-2 signaling to maintain vascular integrity.\",\n      \"method\": \"ES cell-derived endothelial culture, antagonistic monoclonal antibody treatment, cytological analysis\",\n      \"journal\": \"Blood\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — functional assay with specific antibody in defined in vitro system, single lab\",\n      \"pmids\": [\"12393458\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2003,\n      \"finding\": \"VEGFR-3 is expressed on corneal dendritic cells (CD11c+CD45+CD11b+, MHC class II-negative immature DCs of monocytic lineage), which also upregulate VEGF-C during inflammation; this represents expression of VEGFR-3 outside the endothelial compartment.\",\n      \"method\": \"Immunofluorescence, flow cytometry, phenotypic characterization of corneal cells\",\n      \"journal\": \"The American journal of pathology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — direct cell phenotyping with multiple markers, single lab\",\n      \"pmids\": [\"12819011\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"In zebrafish, a loss-of-function mutation in the kinase insert region of flt4 impairs lymphatic vascular development. Dll4 suppresses arterial responsiveness to Vegfc/Flt4 signaling: loss of dll4 causes arterial hyperbranching driven by Vegfc/Flt4, and overexpression of dll4 inhibits Vegfc/Flt4-dependent angiogenesis.\",\n      \"method\": \"Forward genetic screen, zebrafish mutant characterization, morpholino knockdown, genetic epistasis\",\n      \"journal\": \"Development\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — loss-of-function genetics plus epistasis experiments in vivo, replicated with multiple genetic tools\",\n      \"pmids\": [\"19906867\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"Sumoylation of the transcription factor Prox1 at Lys556 is required for Prox1 to bind DNA, activate transcription, and induce VEGFR3 expression in endothelial cells. Mutation K556R or SENP2-mediated desumoylation abolishes Prox1-induced VEGFR3 expression and lymphatic phenotypes.\",\n      \"method\": \"In vitro sumoylation assay, site-directed mutagenesis, reporter gene assay, ectopic expression in endothelial cells\",\n      \"journal\": \"Journal of cell science\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — in vitro sumoylation assay plus mutagenesis plus functional rescue/loss experiments, single lab with multiple orthogonal methods\",\n      \"pmids\": [\"19706680\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"A homozygous VEGFR3 mutation (A855T, in the ATP-binding domain) causes recessive primary congenital lymphedema; the mutant receptor shows impaired ligand-induced internalization, reduced ERK1/2 activity, and reduced phosphorylation compared to wild-type, though not as severely as kinase-dead mutations.\",\n      \"method\": \"Patient genetic analysis, receptor function assays (internalization, phosphorylation, ERK activation)\",\n      \"journal\": \"Journal of medical genetics\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — direct receptor functional assays on patient-derived mutation, single lab\",\n      \"pmids\": [\"19289394\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"VEGFR-3 ligand-binding domain and kinase activity are required for lymphangiogenesis but not for angiogenesis. Both wild-type and kinase-dead VEGFR-3 can form heterodimers with VEGFR-2 and decrease phospho-VEGFR-2 and phospho-ERK1/2 levels in endothelial cells treated with VEGF-A.\",\n      \"method\": \"Conditional knock-in mice (ligand-binding domain deletion and kinase-dead point mutation), co-immunoprecipitation for heterodimer detection, phosphorylation assays\",\n      \"journal\": \"Cell research\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — two complementary genetic mouse models plus biochemical heterodimer and signaling assays, single lab with multiple orthogonal methods\",\n      \"pmids\": [\"20697430\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"Tbx1 transcription factor activates Vegfr3 transcription by binding to an enhancer element in the Vegfr3 gene in endothelial cells; conditional deletion of Tbx1 in ECs causes widespread lymphangiogenesis defects.\",\n      \"method\": \"ChIP, reporter assay, conditional knockout mouse, in vitro transcription assays\",\n      \"journal\": \"The Journal of cell biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — direct ChIP showing Tbx1 binding to Vegfr3 enhancer plus functional genetic validation in vivo\",\n      \"pmids\": [\"20439995\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"R-spondin1 (Rspo1)/Wnt signaling promotes angiogenesis in zebrafish through the Vegfc/Vegfr3(Flt4) axis: Vegfc expression is dependent on Rspo1 and Wnt, and Vegfc/Vegfr3 are necessary downstream of Rspo1-Wnt for angiogenesis.\",\n      \"method\": \"Forward genetic screen in zebrafish, morpholino knockdown, epistasis analysis, endothelial-autonomous Wnt inhibition\",\n      \"journal\": \"Development\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — genetic epistasis with multiple loss-of-function tools in vivo establishing pathway order\",\n      \"pmids\": [\"22007135\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"Notch signaling strongly suppresses VEGFR3 expression; loss of Notch leads to VEGFR3 upregulation and excessive sprouting. VEGFR3 kinase-activity inhibitors (but not ligand-blocking antibodies) suppress sprouting in low-Notch endothelium, indicating VEGFR3 can signal in a ligand-independent manner when Notch is inhibited.\",\n      \"method\": \"Inducible loss-of-function genetics in vivo, pharmacological inhibitors, antibody blocking in retinal vasculature\",\n      \"journal\": \"Nature\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — combined genetic and pharmacological approaches in vivo with rigorous controls, published in Nature\",\n      \"pmids\": [\"22426001\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"miR-1236 (a mirtron) binds the 3' UTR of VEGFR3 mRNA, causing translational inhibition and specifically reducing VEGFR3 (but not VEGFR2) expression in human lymphatic endothelial cells; overexpression decreases VEGFR3 signaling, LEC migration, tube formation, and in vivo lymphangiogenesis.\",\n      \"method\": \"3' UTR luciferase reporter assay, miRNA overexpression in LECs, in vivo lymphangiogenesis assay\",\n      \"journal\": \"Arteriosclerosis, thrombosis, and vascular biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — direct 3' UTR binding assay plus functional validation, single lab\",\n      \"pmids\": [\"22223733\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"VEGF-C activates AKT signaling via formation of a VEGFR3/VEGFR2 heterodimer complex (requiring neuropilin-1), while ERK1/2 is activated via VEGFR3 homodimers. Silencing VEGFR2 or neuropilin-1 abolishes VEGF-C-induced AKT but not ERK activation. Vascular endothelial phosphotyrosine phosphatase (VE-PTP) restrains both ERK and AKT pathways downstream of VEGFR3.\",\n      \"method\": \"Co-immunoprecipitation, siRNA silencing, phosphorylation assays in primary human lymphatic endothelial cells\",\n      \"journal\": \"Arteriosclerosis, thrombosis, and vascular biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple orthogonal methods (co-IP, siRNA, kinase assays) dissecting pathway bifurcation, single lab\",\n      \"pmids\": [\"25524775\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"Integrin-linked kinase (ILK) impedes interaction between VEGFR3 and β1 integrin; mechanical stimulation disrupts ILK-β1 integrin assembly, releasing β1 integrin to interact with VEGFR3 and hyper-activate VEGFR3 signaling. Endothelial-specific ILK deletion leads to excessive VEGFR3 phosphorylation and lymphatic overgrowth rescued by Itgb1 haploinsufficiency.\",\n      \"method\": \"Endothelial-specific conditional knockout mice, co-immunoprecipitation, phosphorylation assays, genetic rescue experiments\",\n      \"journal\": \"The EMBO journal\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — genetic interaction confirmed by double conditional KO rescue plus biochemical co-IP, multiple orthogonal methods\",\n      \"pmids\": [\"30518533\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"VEGFR2 is required for postnatal retinal angiogenesis independently of VEGFR3 and Notch; VEGFR2 is required for DLL4 upregulation and for VEGFR3 functions in angiogenesis. In contrast, VEGFR3 (but not VEGFR2) is essential for postnatal lymphangiogenesis and adult lymphatic vessel maintenance.\",\n      \"method\": \"Conditional deletion of Vegfr2 and Vegfr3 in mice, Notch pathway inhibitor treatment, retinal vascular phenotyping\",\n      \"journal\": \"Proceedings of the National Academy of Sciences\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — conditional double knockouts with epistasis analysis, published in high-impact journal\",\n      \"pmids\": [\"25561555\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"VEGFR3 is expressed on tumor-associated macrophages (TAMs) that infiltrate chemotherapy-treated tumors; VEGFR3-expressing macrophages induce lymphangiogenesis in a VEGF-C/VEGFR3-dependent manner. Blocking VEGF-C/VEGFR3 inhibits pro-metastatic macrophage activity.\",\n      \"method\": \"VEGFR3 blocking in murine tumor models, macrophage transfer experiments, in vivo lymphangiogenesis assay\",\n      \"journal\": \"Cell reports\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — macrophage transfer and antibody blocking experiments in vivo, single lab\",\n      \"pmids\": [\"27783948\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"VEGFR3 limits VEGFR2 expression and VEGF/VEGFR2 pathway activity: deletion of Vegfr3 in blood vascular endothelial cells upregulates VEGFR2 protein and phosphorylation, reduces VE-cadherin at cell junctions, and exacerbates vascular permeability. Concurrent Vegfr2 deletion prevents the excessive permeability seen in Vegfr3-deleted mice.\",\n      \"method\": \"Conditional Vegfr3 deletion in mice, VEGFR3 siRNA in cultured ECs, VEGFR2 phosphorylation assay, VE-cadherin localization, genetic rescue (Vegfr2 co-deletion)\",\n      \"journal\": \"Circulation research\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — conditional KO in vivo plus in vitro silencing plus genetic rescue, multiple orthogonal methods\",\n      \"pmids\": [\"28298294\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"In diabetes, ROS-induced c-Src-dependent (but VEGF-C-independent) VEGFR3 phosphorylation upregulates AP-1, which increases epsin expression; elevated epsins bind and promote degradation of newly synthesized VEGFR3 in the Golgi, reducing cell-surface VEGFR3 availability and impairing lymphangiogenesis.\",\n      \"method\": \"Lymphatic-specific epsin double KO mice, endocytosis assays, VEGFR3 phosphorylation and degradation assays, corneal micropocket and Matrigel assays\",\n      \"journal\": \"The Journal of clinical investigation\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — genetic KO model plus mechanistic phosphorylation/degradation assays, multiple orthogonal methods\",\n      \"pmids\": [\"30102256\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"Heterogeneous deletion of Vegfr3 in lymphatic endothelial cells causes VEGFR3- cells to non-cell-autonomously drive lymphatic hyperplasia by inducing proliferation of neighboring VEGFR3+ LECs through contact-dependent reduction of Notch signaling.\",\n      \"method\": \"Inducible mosaic Vegfr3 deletion in mice, Notch signaling readouts, clonal analysis\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — inducible mosaic genetics in vivo with mechanistic Notch pathway analysis, multiple orthogonal approaches\",\n      \"pmids\": [\"29615616\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"CLEC14A forms a complex with VEGFR-3 in endothelial cells; loss of CLEC14A reduces VEGFR-3 expression with concomitant increases in VEGFR-2 expression and downstream signaling, demonstrating CLEC14A as a regulator of VEGFR-2/VEGFR-3 balance.\",\n      \"method\": \"Co-immunoprecipitation, CLEC14A knockout mice, receptor expression and signaling assays\",\n      \"journal\": \"The Journal of clinical investigation\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — co-IP plus genetic KO with receptor-level readouts, single lab\",\n      \"pmids\": [\"27991863\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"uPARAP endocytic receptor forms a complex with both VEGFR-2 and VEGFR-3, restricts their heterodimerization, and promotes VEGFR-3 signaling through the Crk-II/JNK/paxillin/Rac1 pathway during VEGF-C-driven lymphangiogenesis. Loss of uPARAP leads to hyperbranched lymphatic vasculature in pathological conditions.\",\n      \"method\": \"Co-immunoprecipitation, uPARAP genetic knockout, VEGFR heterodimer assays, pathway inhibition, in vivo lymphangiogenesis models\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — co-IP defining complex, genetic KO in vivo, pharmacological rescue with multiple pathway readouts\",\n      \"pmids\": [\"30518756\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"VEGFR-3 tyrosine kinase inactivation (Chy mouse with I1053F mutation) leads to retention of triglycerides in enterocytes, decreased postprandial plasma TGs, and reduced nitric oxide levels after fat bolus, demonstrating a role for VEGFR-3 signaling in chylomicron entry into intestinal lacteals.\",\n      \"method\": \"Chy mouse model (kinase-dead VEGFR3), lipid absorption assays, NO measurement, enterocyte histology\",\n      \"journal\": \"Frontiers in physiology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — established mouse model with specific kinase-dead mutation, multiple functional readouts, single lab\",\n      \"pmids\": [\"30618798\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"In zebrafish cardiac valve development, Vegfr3/Flt4 is restricted to abluminal endocardial cells by blood flow-activated Notch and Klf2a signaling pathways. Loss of Vegfr3 disrupts valve morphogenesis and causes Notch activation in abluminal cells, revealing antagonistic roles of Vegfr3 (abluminal) and Notch (luminal) in shaping valve leaflets.\",\n      \"method\": \"Zebrafish genetic mutants and transgenic lines, mechanosensitive pathway analysis, live imaging\",\n      \"journal\": \"Cell reports\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetic loss-of-function in zebrafish with epistasis to Notch pathway, single lab\",\n      \"pmids\": [\"32668254\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"FLT4/VEGFR3 recruits AMP-activated protein kinase (AMPK) and directly phosphorylates AMPK-α subunit at Y247 and Y441/Y442 upon bacterial infection in macrophages, thereby coordinating glycolytic reprogramming, autophagy (MAP1LC3 activation), and suppression of CASP1-dependent inflammasome activation/pyroptosis for bacterial elimination.\",\n      \"method\": \"FLT4 mutant (extracellular domain deletion) macrophages, AMPK phosphorylation assays, metabolomics, autophagy assays, AICAR rescue experiments\",\n      \"journal\": \"Autophagy\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — phosphorylation site identification with functional mutant analysis and pharmacological rescue, single lab\",\n      \"pmids\": [\"34632918\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"VEGFC/VEGFR3/ERK signaling directly induces cell-cycle arrest (G1) in venous and lymphatic endothelial precursors in zebrafish, promoting expression of p53 and CDK inhibitors p27/p21, and this G1 arrest is required for vascular sprouting and differentiation.\",\n      \"method\": \"Transgenic zebrafish (cell cycle reporters), VEGFC/VEGFR3 manipulation, CDK inhibitor overexpression, live confocal imaging\",\n      \"journal\": \"Cell reports\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — in vivo live imaging with genetic manipulation establishing causal link between VEGFR3/ERK and cell-cycle arrest, single lab\",\n      \"pmids\": [\"34133928\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"Mitochondrial complex III activity in lymphatic endothelial cells is required for maintaining H3K4me3 and H3K27ac at the Vegfr3 (and Prox1) genomic loci; loss of complex III causes specific downregulation of Vegfr3 and loss of LEC fate.\",\n      \"method\": \"Conditional deletion of mitochondrial complex III QPC subunit in LECs, ChIP for histone marks, gene expression analysis\",\n      \"journal\": \"Science advances\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — conditional genetic KO with direct chromatin modification assays, single lab\",\n      \"pmids\": [\"33931446\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"Ang2 secreted from lymphatic endothelial cells upon VEGF-C stimulation activates Tie2 and Tie1 receptors to fully activate Akt downstream of PI3K, which is required for cell-surface presentation of VEGFR3 on LECs. Blockade of Ang2 or deletion of Tie receptors reduces VEGFR3 surface levels and inhibits lymphangiogenesis.\",\n      \"method\": \"Gene deletion of Tie1, Tie2, Ang2, PI3K-p110α in LECs; Ang2-blocking antibody; VEGFR3 surface expression assays; adult lymphangiogenesis models\",\n      \"journal\": \"The Journal of clinical investigation\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — multiple genetic and pharmacological tools with direct VEGFR3 surface expression readout, replicated across neonatal and adult models\",\n      \"pmids\": [\"35763346\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"VEGFR3 is required for button junction formation in lymphatic capillaries; loss of Flt4 in lymphatic-specific knockout mice prevents button junction development and impairs interstitial absorption. Mechanistically, FLT4 knockdown reduces NOTCH1 expression and activation, and overexpression of the NOTCH1 intracellular domain in Flt4 knockout vessels rescues button junction formation.\",\n      \"method\": \"Lymphatic-specific Flt4 knockout mice, junction morphology analysis, NOTCH1 overexpression rescue, absorption assays\",\n      \"journal\": \"Cell reports\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — genetic KO plus mechanistic rescue with NOTCH1 intracellular domain, multiple functional readouts\",\n      \"pmids\": [\"37454290\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"VEGFR-3 blockade (monoclonal antibody, soluble VEGF-C/D trap, or lymphatic endothelium-specific Vegfr3 deletion) causes regression and functional impairment of dural lymphatic vessels but has no effect on CNS autoimmunity development in mice.\",\n      \"method\": \"VEGFR3-blocking antibody, soluble decoy receptor, inducible conditional Vegfr3 deletion; EAE autoimmune neuroinflammation model\",\n      \"journal\": \"Science immunology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — three independent VEGFR3 inhibition strategies with functional lymphatic and immunological readouts\",\n      \"pmids\": [\"37058549\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"VEGF-C secreted by virally infected neurons activates VEGFR-3 on CNS macrophages, suppressing TNF-α secretion and reducing neuron apoptosis. Vegfr3 ligand-binding domain deletion in myeloid cells or VEGFR-3 kinase inhibitor treatment exacerbates encephalitis severity and neuronal damage.\",\n      \"method\": \"VEGFR-3 ligand-binding domain knockout in myeloid cells (Vegfr3ΔLBD/ΔLBD), VEGFR-3 kinase inhibitor, co-culture assays with conditioned medium, JEV infection mouse model\",\n      \"journal\": \"Cell reports\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — myeloid-specific genetic model plus pharmacological inhibition, single lab\",\n      \"pmids\": [\"37167063\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"FLT4/VEGFR3 is a class III receptor tyrosine kinase that is activated by VEGF-C and VEGF-D (but not VEGF-A) to drive lymphangiogenesis and angiogenesis through homodimers (activating ERK) and heterodimers with VEGFR2 (activating AKT via neuropilin-1); its surface expression is controlled by Ang2/Tie/PI3K signaling, epsin-mediated Golgi degradation, and transcriptional regulators including Prox1 (sumoylation-dependent) and Tbx1; it modulates VEGFR2 activity both positively (via ligand sequestration) and negatively (by limiting VEGFR2 expression in quiescent endothelium), thereby regulating vascular permeability; in angiogenic tip cells it activates Notch to promote tip-to-stalk conversion and is itself suppressed by Notch in a feedback loop; it forms button junctions in lymphatic capillaries via NOTCH1 activation; in macrophages it coordinates bacterial clearance by phosphorylating AMPK and in cardiac valve morphogenesis it is restricted to abluminal endocardial cells to antagonize luminal Notch signaling; loss-of-function mutations in humans cause Milroy disease (autosomal dominant primary lymphedema), while gain-of-function amplification co-occurs with MYC in radiation-induced angiosarcoma.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"FLT4/VEGFR3 is a class III receptor tyrosine kinase, structurally related to FLT1 and KDR, that drives lymphatic and vascular endothelial development by transducing signals from the proteolytically processed ligands VEGF-C and VEGF-D [#0, #7, #9]. Unlike VEGF-A, these ligands induce receptor autophosphorylation, and the activated kinase couples to SHC/GRB2 adaptors to engage downstream signaling [#5, #7]. VEGFR3 bifurcates its output: VEGFR3 homodimers activate ERK1/2, while VEGF-C-driven AKT activation requires a VEGFR3/VEGFR2 heterodimer dependent on neuropilin-1, with VE-PTP restraining both arms [#22]. Its ligand-binding and kinase activities are required for lymphangiogenesis but not angiogenesis, and its kinase activity supports lymphatic vessel maintenance and chylomicron uptake by intestinal lacteals [#17, #24, #31]. VEGFR3 also negatively modulates VEGFR2: by sequestering VEGF-C and by limiting VEGFR2 protein levels, VEGFR3 preserves VE-cadherin junctions and restrains vascular permeability in quiescent endothelium [#10, #26]. VEGFR3 and Notch operate in reciprocal feedback—Notch suppresses VEGFR3 expression while VEGFR3 promotes NOTCH1-dependent button junction formation in lymphatic capillaries, and mosaic loss of VEGFR3 drives non-cell-autonomous hyperplasia through reduced Notch signaling [#20, #28, #37]. Surface availability of VEGFR3 is tightly controlled by Ang2/Tie/PI3K-AKT signaling and by epsin-mediated Golgi degradation, while its transcription is governed by sumoylated Prox1, Tbx1, and mitochondrial complex III-dependent histone modifications at the Vegfr3 locus [#15, #18, #27, #35, #36]. Beyond endothelium, VEGFR3 is expressed on macrophages and dendritic cells, where it directs lymphangiogenesis and, in infected macrophages, phosphorylates AMPK-\\u03b1 to coordinate glycolytic reprogramming, autophagy, and inflammasome suppression [#13, #25, #33]. Loss-of-function VEGFR3 mutations cause primary congenital lymphedema [#16].\"\n,\n  \"teleology\": [\n    {\n      \"year\": 1992,\n      \"claim\": \"Established FLT4 as a transmembrane receptor tyrosine kinase belonging to the VEGFR/class III subfamily, defining its molecular identity before any ligand or function was known.\",\n      \"evidence\": \"cDNA cloning, sequencing, and structural analysis; chromosomal mapping\",\n      \"pmids\": [\"1327515\", \"8386825\", \"1310071\", \"1319394\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"No ligand identified\", \"No functional or signaling role established\"]\n    },\n    {\n      \"year\": 1993,\n      \"claim\": \"Localized FLT4 expression to vascular endothelium of developing vessels and revealed isoform diversity, hinting at a developmental vascular role and tail-dependent functional variation.\",\n      \"evidence\": \"In situ hybridization in fetal tissues; cDNA/genomic analysis of two C-terminal isoforms; biochemical characterization of the ~170 kDa glycoprotein\",\n      \"pmids\": [\"8245783\", \"7692369\", \"8386825\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Functional difference between isoforms not yet tested\", \"Signaling output unknown\"]\n    },\n    {\n      \"year\": 1994,\n      \"claim\": \"Showed FLT4 does not respond to VEGF-A and, using a chimeric receptor, that its activated kinase couples to SHC/GRB2 adaptors, distinguishing it from FLT1/KDR and defining its proximal signaling.\",\n      \"evidence\": \"CSF-1R/FLT4 chimera, SH2-domain binding assays, autophosphorylation and thymidine incorporation assays\",\n      \"pmids\": [\"7970715\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Cognate ligand not identified\", \"Chimera does not establish native ligand-dependent signaling\"]\n    },\n    {\n      \"year\": 1995,\n      \"claim\": \"Demonstrated the long FLT4 isoform confers transforming potential, linking C-terminal tail differences to distinct biological outputs.\",\n      \"evidence\": \"Soft agar colony assay with CSF-1R/FLT4 chimeras in Rat-2 cells\",\n      \"pmids\": [\"7898938\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Relies on chimeric receptor not native ligand\", \"Mechanism of isoform-specific transformation unresolved\"]\n    },\n    {\n      \"year\": 1997,\n      \"claim\": \"Identified VEGF-C as the cognate ligand activating FLT4 and mapped a downstream Shc/Grb2/SOS, RAFTK, JNK and paxillin signaling complex, converting the orphan receptor into a defined lymphatic mitogenic pathway.\",\n      \"evidence\": \"BIAcore binding, affinity chromatography, phosphorylation and mitogenesis assays; co-IP and kinase assays in HEL cells\",\n      \"pmids\": [\"9247316\", \"9345034\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Second ligand and receptor heterodimerization not yet addressed\", \"In vivo lymphatic role not yet tested\"]\n    },\n    {\n      \"year\": 1998,\n      \"claim\": \"Defined VEGF-D as a second ligand shared with VEGFR-2, broadening the receptor's ligand repertoire and foreshadowing VEGFR2/VEGFR3 crosstalk.\",\n      \"evidence\": \"Receptor-binding and activation assays with deletion mutants\",\n      \"pmids\": [\"9435229\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Functional consequences of dual-receptor binding unclear\", \"No structural model of ligand-receptor engagement\"]\n    },\n    {\n      \"year\": 2000,\n      \"claim\": \"Revealed that VEGFR3 controls VEGFR2 signaling by sequestering VEGF-C, establishing the first inter-receptor regulatory mechanism.\",\n      \"evidence\": \"P-Sp/OP9 coculture, VEGFR3-deficient mouse embryos, soluble receptor competition\",\n      \"pmids\": [\"11090062\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Molecular basis of crosstalk (heterodimer vs. ligand competition) not separated\", \"Adult vascular consequences untested\"]\n    },\n    {\n      \"year\": 2001,\n      \"claim\": \"Characterized the VEGFR3 promoter as a TATA-less endothelial-specific element, opening study of its transcriptional control.\",\n      \"evidence\": \"Reporter transfection and transgenic mouse promoter assays\",\n      \"pmids\": [\"11292664\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Trans-acting factors not identified\", \"Weak lymphatic activity suggests missing enhancers\"]\n    },\n    {\n      \"year\": 2002,\n      \"claim\": \"Showed VEGFR3 negatively modulates VEGFR2 activity to maintain vascular integrity, extending its regulatory role to endothelial behavior.\",\n      \"evidence\": \"Antagonistic VEGFR3 antibody (AFL4) in ES-derived endothelial cultures with cytological analysis\",\n      \"pmids\": [\"12393458\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Antibody mechanism (block vs. activate) ambiguous\", \"In vivo permeability link not established\"]\n    },\n    {\n      \"year\": 2003,\n      \"claim\": \"Documented VEGFR3 expression on immature dendritic cells, the first evidence of a non-endothelial functional compartment.\",\n      \"evidence\": \"Immunofluorescence and flow cytometry of corneal dendritic cells\",\n      \"pmids\": [\"12819011\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Function of VEGFR3 on DCs not defined\", \"Signaling in myeloid cells unaddressed\"]\n    },\n    {\n      \"year\": 2009,\n      \"claim\": \"Connected VEGFR3 to transcriptional and developmental control circuits, showing Prox1 sumoylation drives VEGFR3 expression, Dll4/Notch restrains Vegfc/Flt4 angiogenic responses, and a human kinase-domain mutation causes recessive lymphedema.\",\n      \"evidence\": \"In vitro sumoylation and reporter assays; zebrafish forward genetics and epistasis; patient mutation functional assays\",\n      \"pmids\": [\"19706680\", \"19906867\", \"19289394\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Mechanism coupling Notch to VEGFR3 expression not yet defined\", \"Allelic spectrum of human disease incomplete\"]\n    },\n    {\n      \"year\": 2010,\n      \"claim\": \"Separated VEGFR3 requirements for lymphangiogenesis versus angiogenesis and showed kinase-independent heterodimer suppression of VEGFR2, and identified Tbx1 as a direct transcriptional activator of Vegfr3.\",\n      \"evidence\": \"Conditional knock-in mice (ligand-binding-deletion and kinase-dead); co-IP heterodimer detection; ChIP and conditional Tbx1 knockout\",\n      \"pmids\": [\"20697430\", \"20439995\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Structural basis of heterodimer-mediated VEGFR2 suppression unknown\", \"Other enhancer-binding factors not catalogued\"]\n    },\n    {\n      \"year\": 2011,\n      \"claim\": \"Placed Vegfc/Vegfr3 downstream of Rspo1/Wnt signaling, embedding the receptor in a defined upstream developmental cascade.\",\n      \"evidence\": \"Zebrafish forward genetics, morpholino knockdown, endothelial-autonomous Wnt inhibition, epistasis\",\n      \"pmids\": [\"22007135\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Direct vs. indirect Wnt-to-Vegfc link not resolved\", \"Mammalian conservation untested in this study\"]\n    },\n    {\n      \"year\": 2012,\n      \"claim\": \"Defined a Notch–VEGFR3 feedback loop and ligand-independent VEGFR3 kinase signaling, and identified miR-1236 as a post-transcriptional brake, refining the control of endothelial sprouting.\",\n      \"evidence\": \"Inducible Notch loss-of-function with pharmacological/antibody dissection in retina; 3'UTR luciferase and miRNA overexpression in LECs\",\n      \"pmids\": [\"22426001\", \"22223733\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Mechanism of ligand-independent kinase activation undefined\", \"Physiological miR-1236 regulation not established in vivo\"]\n    },\n    {\n      \"year\": 2014,\n      \"claim\": \"Dissected the VEGFR3 signaling bifurcation—ERK via homodimers, AKT via NRP1-dependent VEGFR2 heterodimers—and identified mechanotransductive control through ILK/\\u03b21-integrin.\",\n      \"evidence\": \"Co-IP, siRNA silencing, phosphorylation assays in LECs; endothelial-specific ILK knockout with Itgb1 genetic rescue\",\n      \"pmids\": [\"25524775\", \"30518533\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Structural geometry of the homodimer vs heterodimer outputs not resolved\", \"How \\u03b21 integrin hyperactivates VEGFR3 mechanistically unclear\"]\n    },\n    {\n      \"year\": 2015,\n      \"claim\": \"Genetically separated VEGFR2 and VEGFR3 requirements, fixing VEGFR3 as essential for lymphangiogenesis and lymphatic maintenance but dispensable for retinal angiogenesis.\",\n      \"evidence\": \"Conditional double knockouts in mice with Notch inhibition and retinal phenotyping\",\n      \"pmids\": [\"25561555\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Context-dependence of VEGFR3 angiogenic contribution not fully mapped\"]\n    },\n    {\n      \"year\": 2016,\n      \"claim\": \"Established a tumor-promoting role for VEGFR3 on macrophages, where VEGF-C/VEGFR3 drives lymphangiogenesis and pro-metastatic activity.\",\n      \"evidence\": \"VEGFR3 blockade and macrophage transfer in murine tumor models\",\n      \"pmids\": [\"27783948\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Macrophage-intrinsic VEGFR3 signaling not defined\", \"Single-lab tumor model\"]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"Showed VEGFR3 limits VEGFR2 protein levels to protect endothelial junctions and restrain permeability, with VEGFR2 co-deletion rescuing the phenotype.\",\n      \"evidence\": \"Conditional Vegfr3 deletion, EC siRNA, VEGFR2 phosphorylation and VE-cadherin assays, Vegfr2 co-deletion rescue\",\n      \"pmids\": [\"28298294\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Mechanism by which VEGFR3 limits VEGFR2 abundance unknown\", \"Relation to ligand-sequestration model not unified\"]\n    },\n    {\n      \"year\": 2018,\n      \"claim\": \"Uncovered multiple layers of VEGFR3 surface and activity control—epsin-mediated Golgi degradation in diabetes, CLEC14A and uPARAP complexes balancing VEGFR2/VEGFR3, non-cell-autonomous Notch-dependent hyperplasia, and a chylomicron-absorption role.\",\n      \"evidence\": \"Lymphatic epsin double KO and degradation assays; CLEC14A and uPARAP co-IP and KO; mosaic Vegfr3 deletion with Notch readouts; Chy kinase-dead mouse lipid assays\",\n      \"pmids\": [\"30102256\", \"27991863\", \"30518756\", \"29615616\", \"30618798\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether these regulators converge on a single trafficking node is unclear\", \"uPARAP/CLEC14A direct binding interfaces undefined\"]\n    },\n    {\n      \"year\": 2021,\n      \"claim\": \"Expanded VEGFR3 outputs to direct AMPK phosphorylation in macrophages for antibacterial defense, ERK-driven cell-cycle arrest in endothelial precursors, and a mitochondrial complex III–chromatin axis sustaining Vegfr3 expression.\",\n      \"evidence\": \"FLT4 mutant macrophage AMPK phosphorylation/autophagy/metabolomics assays; zebrafish cell-cycle reporters; LEC complex III conditional KO with histone-mark ChIP\",\n      \"pmids\": [\"34632918\", \"34133928\", \"33931446\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct AMPK phosphorylation needs structural/kinetic confirmation\", \"Single-lab findings for each mechanism\"]\n    },\n    {\n      \"year\": 2022,\n      \"claim\": \"Defined an Ang2/Tie/PI3K-AKT requirement for cell-surface presentation of VEGFR3, linking angiopoietin signaling to receptor availability.\",\n      \"evidence\": \"Tie1, Tie2, Ang2, PI3K-p110\\u03b1 deletions and Ang2-blocking antibody with VEGFR3 surface assays across neonatal and adult models\",\n      \"pmids\": [\"35763346\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Molecular step linking AKT to VEGFR3 trafficking unidentified\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Established VEGFR3 control of NOTCH1-dependent button junction formation, a dural-lymphatic role separable from CNS autoimmunity, and a neuroprotective VEGF-C/VEGFR3 axis on CNS macrophages.\",\n      \"evidence\": \"Lymphatic-specific Flt4 KO with NOTCH1-ICD rescue; three VEGFR3-inhibition strategies in EAE; myeloid Vegfr3\\u0394LBD model in JEV encephalitis\",\n      \"pmids\": [\"37454290\", \"37058549\", \"37167063\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"How VEGFR3 induces NOTCH1 expression mechanistically unresolved\", \"Macrophage VEGFR3 signaling pathway to TNF-\\u03b1 suppression undefined\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How VEGFR3 toggles between ligand-dependent and ligand-independent signaling, and the unified structural/trafficking logic that integrates VEGFR2 crosstalk, Notch feedback, and surface-expression control, remains unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No structural model of the VEGFR3 homodimer vs VEGFR2 heterodimer signaling states\", \"Mechanism of ligand-independent kinase activation undefined\", \"Convergence point of the multiple surface/abundance regulators unknown\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0140096\", \"supporting_discovery_ids\": [5, 7, 22, 33]},\n      {\"term_id\": \"GO:0016740\", \"supporting_discovery_ids\": [0, 7, 33]},\n      {\"term_id\": \"GO:0004714\", \"supporting_discovery_ids\": [0]},\n      {\"term_id\": \"GO:0048018\", \"supporting_discovery_ids\": [7, 9]},\n      {\"term_id\": \"GO:0060089\", \"supporting_discovery_ids\": [7, 17, 22]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005886\", \"supporting_discovery_ids\": [6, 16, 36]},\n      {\"term_id\": \"GO:0005794\", \"supporting_discovery_ids\": [27]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-162582\", \"supporting_discovery_ids\": [7, 17, 22]},\n      {\"term_id\": \"R-HSA-1266738\", \"supporting_discovery_ids\": [14, 17, 24, 32]},\n      {\"term_id\": \"R-HSA-168256\", \"supporting_discovery_ids\": [13, 25, 33, 39]},\n      {\"term_id\": \"R-HSA-9612973\", \"supporting_discovery_ids\": [33]}\n    ],\n    \"complexes\": [\n      \"VEGFR3/VEGFR2 heterodimer\",\n      \"VEGFR3/uPARAP/VEGFR2 complex\",\n      \"VEGFR3/CLEC14A complex\"\n    ],\n    \"partners\": [\n      \"KDR\",\n      \"NRP1\",\n      \"SHC\",\n      \"GRB2\",\n      \"CLEC14A\",\n      \"uPARAP\",\n      \"ITGB1\",\n      \"PRKAA\"\n    ],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":9,"faith_total":9,"faith_pct":100.0}}