WTAP and cholangiocarcinoma: Besides its essential physiological processes in cell cycle regulation (4), mRNA stabilization (5), RNA alternative splicing (6), m6A methylation (7), and eye development (8), WTAP has also been demonstrated to act as an oncogene in the tumorigenesis of malignant cancers, such as renal cell carcinoma (RCC), glioma, colorectal cancer (CRC), pancreatic ductal adenocarcinoma (PDAC), cholangiocarcinoma (CCA), ovarian cancer, bladder cancer, and acute myelogenous leukemia (AML) (9–17).