Targeting ADAR1 with a small molecule for the treatment of prostate cancer

Abstract Despite initial response to androgen signaling therapy, most prostate cancer (PCa) patients eventually relapse and remain incurable. ADAR1-mediated A-to-G editing plays oncogenic roles in various tumors. However, the specific function of ADAR1 and the global RNA edited targets governing PCa progression remain underexplored. Here, we demonstrate that highly expressed ADAR1 as a crucial oncogenic target in PCa, and develop a novel small-molecule ADAR1 inhibitor ZYS-1 with significant anti-tumor efficacy and favorable safety profile. Either depletion or pharmacological inhibition of ADAR1 dramatically suppress PCa growth, inhibit metastasis, and potentiate immune response. We further reveal that the translation of MTDH is repressed by ADAR1 in an editing-dependent manner, which drives cell proliferation and invasion in PCa. Collectively, these results shed light on ADAR1 as a novel druggable target in PCa therapy and highlight the widespread applicability of ADAR1 inhibitors for a broad spectrum of malignancies.