Prognostic role of high MTAP expression is reversed by the ERG status in prostate cancer treated by radical prostatectomy.

ABSTRACT: Loss of S-methyl-5'-thioadenosine phosphorylase (MTAP) expression offers a therapeutic option through synthetic lethality and confers resistance to immune checkpoint inhibitors in various cancers. To assess MTAP prevalence in prostate cancer, a tissue microarray of 17,747 samples was analyzed via immunohistochemistry. Normal prostate glands showed weak to moderate cytoplasmic MTAP staining. In 13,189 interpretable cancers, a complete loss of MTAP staining was seen in 33 (0.3 %) tumors, while MTAP staining was considered 1+ in 14.8 %, 2+ in 42.2 %, and 3+ in 42.7 % of tumors. Fluorescence in situ hybridization analysis of 9 MTAP-negative cancers confirmed homozygous MTAP deletion in all of these tumors. MTAP staining was significantly stronger in cancers harboring the TMPRSS2:ERG fusion tha

SUBMITTER: Gorbokon N 

PROVIDER: S-EPMC12214127 | biostudies-literature | 2025 Sep

REPOSITORIES: biostudies-literature