Apoptotic Effect of Phycocyanin on HT-29 Colon Cancer through Activation of Caspase Enzymes and P53 Cell Signaling Pathway

C-phycocyanin, a biliprotein from Spirulina platensis, is a future candidate for cancer management. This agent is originated from edible blue-green algae, and numerous in vivo and in vitro research have reported on its anti-cancer properties. The effects of C-phycocyanin have been investigated on caspases 3, 8, 9, and p53 pathways in the human colorectal adenocarcinoma cell line (HT-29) and human umbilical vein endothelial cells (HUVECs).

In the current study, we investigated the effect of C-phycocyanin on caspase 3, 8, 9, and p53-mediated apoptosis pathways in two cell lines (HT-29 & HUVEC), using quantitative real-time PCR and flow cytometry. The cytotoxicity of phycocyanin on HT-29 cells was compared with HUVEC normal cells via colorimetric assays.

Based on our findings at molecular level, the expression of caspases 3, 8, 9, and p53 genes were increased in colorectal cancer cells treated with C-phycocyanin.The results were confirmed by an increase in the number of colorectal cancer cells in the early and late stages of apoptosis as compared to the control, untreated cells. In addition, the results of colorimetric assay showed that C-phycocyanin has no cytotoxic effects on normal HUVECs cells.

Based on our experimental data, it is evident that C-phycocyanin has measurable effects on cell apoptosis. Since tumorigenesis is halted by apoptosis, C-phycocyanin can be a hopeful candidate for the treatment of human colorectal cancer in the future.