Isolation and characterisation of colon cancer stem cells and the effects of epigenetic modulation on pluripotent markers

Abstract

Colorectal cancer has a 9.8% cumulative incidence rate, making it the third most common cancer in the Western world. Despite a 50-60% response rate in patients to current cancer therapies, drug resistance and tumour relapse remain a concern. While current therapies reduce the tumour mass, they possibly fail to eradicate a unique population of pluripotent tumour resident cells. These cells, known as cancer stem cells, may have similar properties of self-renewal and proliferation to embryonic and adult stem cells, as they also express a number of key pluripotent transcription factors, including amongst others, NANOG, OCT3/4 and SOX2. Furthermore, since discreet groups of such stem cells are proposed to essentially drive tumourigenesis, they present as potential novel targets for cancer therapy. This study aimed to isolate a putative CSC population from the advanced colon adenocarcinoma cell lines HT29 and DLD1 and to assess the therapeutic effects of the epigenetic drugs Valproic acid and Zebularine on pluripotent gene expression.