KLK3
Overview
KLK3 (Kallikrein Related Peptidase 3), commonly known as PSA (Prostate-Specific Antigen), encodes a serine protease that is transcriptionally regulated by the androgen receptor (AR). KLK3 is the canonical clinical biomarker for prostate cancer detection, staging, and treatment response monitoring. Its expression is nearly exclusively restricted to prostate epithelium and is maintained even in castration-resistant prostate cancer, making it a key readout of AR pathway activity.
Alterations observed in the corpus
- KLK3 (PSA) listed as a gene of interest in prostate cancer WES cohort (Michigan, 112 tumors) examining ETS fusions and chromatin modifier mutations in castration-resistant prostate cancer PMID:22722839
Cancer types (linked)
- PRAD: KLK3 is an AR-regulated gene central to prostate cancer biology; its expression serves as a clinical biomarker and surrogate marker of AR pathway activity in castration-resistant disease PMID:22722839
Co-occurrence and mutual exclusivity
- KLK3 expression is regulated by AR and influenced by AR cofactors including FOXA1 and chromatin modifiers (KMT2D, KDM6A) identified as mutated in the same prostate cancer cohort PMID:22722839
Therapeutic relevance
- KLK3/PSA is used clinically to monitor response to androgen deprivation therapy (ADT) and next-generation AR-targeting agents; PSA nadir and PSA progression define treatment milestones in CRPC PMID:22722839
Open questions
- Whether somatic mutations in KLK3 itself drive prostate cancer is not established; its primary relevance is as a biomarker and AR pathway readout
Sources
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