Cancer Stem Cells in Colorectal Cancer: Genetic and Epigenetic Changes.

Colorectal cancer (CRC), an age-related disease, is the third most common cancer in the world. Although sporadic CRC, that affects 80-85% of CRC patients, is a multi-step process initiated by APC gene mutation, it is becoming increasingly evident that a small sub-population of cells termed cancer stem/stem-like cells (CSCs/CSLCs) plays critical roles in the progression of this malignancy specially the recurrence and drug resistance. The current review will summarize genetic and epigenetic changes observed at different stages in the progression of sporadic CRC. In addition, roles of miRNAs that control gene expression and CSCs/CSLCs in regulating proliferation, differentiation, and survival of the colon cancer cells will be summarized.