CA4 and colorectal carcinoma: Another m6A eraser ‘FTO’ polymorphism has no association with the risk of CRC [80], but the m6A ‘writer’ WTAP is associated with carbonic anhydrase IV (CA4), which inhibits the proliferation and induces apoptosis and cycle arrest by repressing the Wnt signaling through targeting the WTAP-WT1-TBL1 axis [81].