APC and colorectal adenoma: APC mutations are also found in 80% of colorectal adenomas and CRCs and are one of the earliest mutations in the progression of colon cancer.199–201 APC allele deletion activates Wnt/β-catenin signalling by inhibiting the formation of the degradation complex, which drives CRC development, endows cancer cells with self-renewal growth characteristics and is related to therapeutic drug resistance.202–204