METTL3 and urinary bladder cancer: m6A methyltransferase METTL3 is up-regulated in prostate cancer and bladder cancer cell lines, which promotes cell proliferation and survival, while silencing of METTL3 in these cell lines results in decreased cell proliferation and survival, suggesting that METTL3 contributes to the pathogenesis of prostate cancer and bladder cancer (Cai et al., 2019; Han J. et al., 2019).