APC and colitis: Although the pathogenesis of colitis-associated CRC differs from that of sporadic CRC, they share several common characteristic mechanisms such as aneuploidy, mutations in APC (adenomatous polyposis coli) gene, DNA methylation, oncogene k-ras activation, microsatellite instability (MSI), COX-2 activation, tumor suppressor gene DCC/DPC4 mutation, and eventual loss of p53 functions [57].