Anti-cancer properties of Escherichia coli Nissle 1917 against HT-29 colon cancer cells through regulation of Bax/Bcl-xL and AKT/PTEN signaling pathways.

Abstract

Objective(s):Chemotherapies used to treat colon cancer might often fail due to the emergence of chemoresistance and side effects. Escherichia coli Nissle 1917 (EcN) is a beneficial probiotic, whose molecular mechanisms in the prevention of colon cancer are yet to be fully understood. The present study assessed the anti-cancer effects of EcN treatments in human colorectal cancer, HT-29 cell line, with the analysis of related mechanisms. Materials and Methods:The co-culture conditioned-media (CM) of EcN with adenocarcinoma HT-29 cells and heat-inactivated bacteria (HIB) were applied for the treatment of the HT-29 cells. To study the inhibition potential of CM and HIB on cancer cells, various cellular/molecular analyses were implemented, including DAPI-staining and DNA ladder assays, flow cytometry and Real-time quantitative PCR (qPCR), as well as Western blotting analyses.Results:Our results indicated that EcN could elicit apoptotic impacts on the colon cancer HT-29 cells by up-regulating PTEN and Bax and down-regulating AKT1 and Bcl-xL genes. Conclusion:Based on our findings, EcN is proposed as a useful supplemental probiotic treatment against colon cancer.