Increase in apoptosis by combination of metformin with silibinin in human colorectal cancer cells.
World J Gastroenterol. 2015 Apr 14 ;21(14):4169-77. PMID: 25892866
AIM: To investigate the effect of metformin on silibinin-induced apoptosis in human colorectal cancer (COLO 205) cells.
METHODS: MTT assays were performed to quantify cell viability. Western blot assays were applied to identify the expression of signaling proteins.
RESULTS: The combined treatment of COLO 205 cells with metformin and silibinin decreased cell survival at a dose insufficient to influence the non-malignant cells [Human colonic epithelial cells (HCoEpiC)]. Silibinin and metformin increased phosphatase and tensin homolog and 5'-adenosine monophosphate-activated protein kinase expression in COLO 205 cells and inhibited the phosphorylation of mammol/Lalian target of rapamycin. This combined treatment resulted in an increase in the expression of activated caspase 3 and apoptosis inducing factor, indicating apoptosis.
CONCLUSION: The combined treatment of human colorectal cancer cells with silibinin and metformin may induce apoptosis at a dose that does not affect HCoEpiC. This finding reveals a potential therapeutic strategy for the treatment of colorectal cancer.