However, neither APC nor KRAS mutation alone induce severe CRC phenotype, especially KRAS mutation alone, in the mouse model.6,40 The highlight of outcomes by both APC and KRAS mutations in CRC is activation of CSCs and observation of liver metastasis in the xenograft mice model using a CRC cell line harboring both APC and KRAS mutation. Here, KRAS is linked to colorectal carcinoma.