In light of the methylation activity of the METTL1-WDR4 complex, increasing evidence confirms the oncogenic role in various cancers, such as acute myeloid leukemia [86,92], bladder cancer [93], hepatocellular carcinoma [94], prostate cancer [95], etc. The expression levels of the METTL1-WDR4 complex are prevalently higher in tumor samples and associated with poor prognoses in patients [86,96]. The gene discussed is WDR4; the disease is urinary bladder cancer.