PIK3R2
Overview
PIK3R2 encodes the p85-beta regulatory subunit of class IA phosphatidylinositol 3-kinases. It forms heterodimers with class IA PI3K catalytic subunits (PIK3CA, PIK3CB, PIK3CD) and modulates PI3K activity and membrane recruitment. Altered expression of PIK3R2 can affect downstream AKT/mTOR signaling and has been observed in neuroendocrine neoplasms.
Alterations observed in the corpus
- High PIK3R2 expression supported TKI selection (sorafenib, pazopanib) for metastatic neuroendocrine neoplasm patient PN1 in a WGTA precision-oncology study of 28 NEN patients PMID:24326773
- PIK3R2 mutated as part of the PI3K/AKT/mTOR pathway, disrupted in 39% ATC vs 11% PDTC (P=1×10⁻³) in a targeted-sequencing study of advanced thyroid cancers. PMID:26878173
- Nominated as a novel PI3K-pathway SMG (1% frequency) in 1,013 prostate tumors (prad_p1000); the recurrent p.Asp557Tyr variant is paralogous to the known oncogenic PIK3R1 p.Asp560Tyr and was reproduced in the MSK-IMPACT validation cohort PMID:29610475.
Cancer types (linked)
- Neuroendocrine neoplasms (NENs) — high expression informing TKI therapy selection in the WGTA precision-oncology cohort PMID:24326773
Co-occurrence and mutual exclusivity
- No co-occurrence or mutual exclusivity data available in the current corpus.
Therapeutic relevance
- High PIK3R2 expression used as rationale for sorafenib and pazopanib (TKI) selection in a metastatic NEN patient PMID:24326773
Open questions
- Whether PIK3R2 overexpression is a predictive biomarker for TKI response in NENs requires prospective validation.
Sources
This page was processed by crosslinker on 2026-05-09. - PMID:26878173
This page was processed by wiki-cli on 2026-05-14. - PMID:29610475
This page was processed by wiki-cli on 2026-05-15.