METTL3, as the most important m6A methyltransferase, has also been extensively studied for its effect on cell proliferation, especially in tumour cells, and showed that METTL3 promotes the proliferation and migration of various tumour cells, such as gastrointestinal cancer, bladder cancer, and colorectal cancer.29, 31. The gene discussed is METTL3; the disease is urinary bladder cancer.