PRMT5 and cancer: MTAP deletion reduces the methyltransferase activity of protein arginine methyltransferase 5 (PRMT5), increases the sensitivity to PRMT5 depletion and confers selective dependence on PRMT5 and its binding partner WDR77 in cancer cells; therefore, inhibitors of PRMT5 are a potential therapeutic target in MTAP-deleted tumors23–25.