Androgen deprivation-mediated activation of AKT is enhanced in prostate cancer with TMPRSS2:ERG fusion.

ABSTRACT: TMPRSS2:ERG gene fusion (T:E fusion) in prostate adenocarcinoma (PCa) puts ERG under androgen receptor-regulated (AR-regulated) TMPRSS2 expression. T:E fusion is associated with PTEN loss and is highly associated with decreased INPP4B expression, which together may compensate for ERG-mediated suppression of AKT signaling. We confirmed in PCa cells and a mouse PCa model that ERG suppresses IRS2 and AKT activation. In contrast, ERG downregulation did not increase INPP4B, suggesting its decrease is indirect and reflects selective pressure to suppress INPP4B function. Notably, INPP4B expression was decreased in PTEN-intact and PTEN-deficient T:E fusion tumors, suggesting selection for a nonredundant function. As ERG in T:E fusion tumors is AR regulated, we further assessed whether AR inhibitio

SUBMITTER: Ma F 

PROVIDER: S-EPMC12646650 | biostudies-literature | 2025 Dec

REPOSITORIES: biostudies-literature