TCF3 and colorectal carcinoma: The TCF3 expression in 39 tumors with promoter methylation was significantly lower than that in 8 cases without promoter methylation (P = 0.001), indicating that promoter hypomethylation was the major mechanism of the upregulation of TCF3. Increased TCF/β-catenin signaling is one of the hallmarks of CRC [20].