USP11 promotes prostate cancer progression by upregulating AR and c-Myc activity [RNA-seq]

Androgen receptor (AR) is a main driver for castration-resistant prostate cancer (CRPC). c-Myc is an oncogene underlying prostate tumorigenesis. Here we find that the deubiquitinase USP11 targets both AR and c-Myc in prostate cancer. USP11 expression was upregulated in metastatic prostate cancer and CRPC. USP11 knockdown significantly inhibited prostate cancer cell growth. Our RNA-seq studies revealed AR and c-Myc as the top transcription factors altered after USP11 knockdown. ChIP-seq analysis showed that either USP11 knockdown or replacement of endogenous USP11 with a catalytic-inactive USP11 mutant significantly decreased chromatin binding by AR and c-Myc. We find that USP11 employs two mechanisms to upregulate AR and c-Myc levels: namely, deubiquitination of AR and c-Myc proteins to increase their stability; deubiquitination of H2A-K119Ub, a repressive histone mark, on promoters of AR and c-Myc genes to increase their transcription. AR and c-Myc re-expression in USP11-knockdown prostate cancer cells partly rescued cell growth defects. Thus, our studies reveal a tumor-promoting role for USP11 in aggressive prostate cancer through upregulation of AR and c-Myc activities and support USP11 as a potential target against prostate cancer.