GINS1

GINS1 (PSF1) is an essential subunit of the eukaryotic GINS complex required for DNA replication, and biallelic loss-of-function mutations impair GINS complex assembly, producing basal replication stress, defective checkpoint signaling, impaired cell cycle control, and genomic instability, with residual GINS1 activity correlating with clinical severity in affected patients (PMID:28414293). Beyond this core replication role, GINS1 expression is a convergence point for multiple oncogenic transcription factors that directly bind its promoter and activate transcription, including NFIX (PMID:36469009), PAX5 (PMID:37221950), FOXP1 (PMID:37576391), E2F1 (PMID:37824372), and SP1 acting downstream of OTUB2 (PMID:39210373); FOXP3 stabilized by MALAT1 likewise drives GINS1 expression (PMID:33972684). At the protein level GINS1 physically interacts with TOP2A, and through USP15-mediated deubiquitination and stabilization of TOP2A it promotes glioma proliferation and migration (PMID:36065190), and it directly binds HRAS to activate HRAS signaling and induce liver cancer stem cell phenotypes (PMID:34414190, PMID:40713555). Across these contexts GINS1 supports the G1/S cell cycle transition and tumor cell proliferation (PMID:37824372, PMID:34414190).

1. 2017 High

   Whether GINS1 is genuinely essential for human DNA replication and how its dosage maps to disease was unknown; patient-derived mutations established GINS1 as required for GINS complex assembly and replication integrity.

   Evidence Patient fibroblast studies with WT GINS1 genetic rescue, checkpoint, cell cycle and genomic instability assays across 5 patients from 4 kindreds

   PMID:28414293

   Open questions at the time

   • Does not resolve the structural basis of how specific mutations impair GINS subunit assembly
   • Does not address GINS1 function outside the replication context
2. 2021 Medium

   It was unclear how GINS1 contributes to tumor aggressiveness beyond replication; loss-of-function studies linked GINS1 to HRAS pathway activation and cancer stem cell properties in HCC.

   Evidence shRNA knockdown with G1/S arrest, spheroid formation, xenografts and HRAS overexpression rescue

   PMID:34414190

   Open questions at the time

   • Did not yet demonstrate a direct GINS1-HRAS physical interaction
   • Mechanism of HRAS pathway engagement by a replication factor unclear
3. 2021 Medium

   How GINS1 transcription is upregulated in cancer was unaddressed; MALAT1-stabilized FOXP3 was shown to drive GINS1 expression in NSCLC.

   Evidence Co-IP, domain mapping, luciferase reporter, knockdown/rescue in vitro and in vivo

   PMID:33972684

   Open questions at the time

   • Direct FOXP3 binding to the GINS1 promoter not mapped at nucleotide resolution
   • Single lab
4. 2022 Medium

   Whether GINS1 has protein partners that act outside replication was open; GINS1 was shown to physically interact with TOP2A and stabilize it via USP15-mediated deubiquitination to drive glioma growth.

   Evidence Reciprocal Co-IP, deubiquitination assays, proliferation/migration assays in vitro and in vivo

   PMID:36065190

   Open questions at the time

   • How GINS1 promotes USP15 recruitment to TOP2A not defined
   • Single lab without independent replication
5. 2023 Medium

   The transcriptional control of GINS1 was clarified by identifying multiple direct promoter-binding activators across cancer types: NFIX, PAX5 and FOXP1.

   Evidence ChIP/EMSA promoter binding, luciferase reporter and rescue assays in GBM, B cells/DLBCL

   PMID:36469009 PMID:37221950 PMID:37576391

   Open questions at the time

   • Whether these factors act combinatorially on the same promoter is unknown
   • Each shown in a distinct single-lab context
6. 2024 Medium

   Additional transcriptional inputs were established, placing GINS1 downstream of E2F1 and of OTUB2-stabilized SP1.

   Evidence ChIP, dual-luciferase reporter, ubiquitination assays and rescue in HCC and colon cancer

   PMID:37824372 PMID:39210373

   Open questions at the time

   • Hierarchy among the many GINS1 activators not resolved
   • Single lab per context
7. 2024 Medium

   The earlier functional link to HRAS was upgraded to a direct physical interaction, defining a GINS1-HRAS axis driving liver cancer stem cell phenotypes.

   Evidence Co-IP and GST pulldown, methylation-specific PCR, sphere formation and xenografts

   PMID:40713555

   Open questions at the time

   • Interaction interface and stoichiometry not mapped
   • Single lab
8. 2024 Low

   GINS1 was placed upstream of several oncogenic signaling cascades across tumor types, though largely by pathway-level readouts.

   Evidence Knockdown/overexpression with Western blot and pharmacological rescue assigning GINS1 to AKT/mTOR, β-catenin, Notch/PI3K and FYN/EMT axes

   PMID:38468464 PMID:38880324 PMID:39631830 PMID:41242545

   Open questions at the time

   • No direct binding or enzymatic assay linking GINS1 to these pathway nodes
   • Pathway placement rests on Western blot and rescue, prone to indirect effects
9. 2026 Low

   GINS1 was positioned as a downstream effector of POLE2 controlling AKT/mTOR-mediated autophagy in renal cell carcinoma.

   Evidence Bioinformatics with GINS1 overexpression rescue of POLE2 knockdown, in vitro/in vivo models, Western blot

   PMID:41893924

   Open questions at the time

   • No direct POLE2-GINS1 binding assay
   • Single lab, indirect pathway evidence

• How GINS1's essential replication function mechanistically intersects with its many reported oncogenic interactions and transcriptional inputs remains unresolved.
• No structural model of GINS1 within the human GINS complex from the corpus
• Whether non-replication interactions (HRAS, TOP2A) depend on or are separable from GINS complex assembly is unknown
• Causal hierarchy among the numerous transcription factors driving GINS1 not established