Novel Effects of Phycocyanin Extract on the Regulation of Apoptosis Genes in Human Colorectal Cancer Cells.

Background: Colorectal cancer (CRC) is among the most common cancers worldwide. In spite of promising improvements, it has a relatively poor prognosis. Therefore, there is a crucial need for discovering novel and efficient therapies. This study aimed to investigate the potential of phycocyanin as a therapeutic agent for CRC, considering its antioxidant and anti-inflammatory properties. Methods: The study used HT-29 and HUVEC cell lines. Cells were exposed to different concentrations of phycocyanin for 24 h. The cytotoxic effects of the phycocyanin on HUVEC and HT-29 cells were evaluated using MTT. Following the treatment, RNA extraction was conducted using TRI reagent. Afterward, real-time PCR (RT-PCR) was performed on Bcl-2, Bax, Akt, PTEN, and ß-actin to study their expression levels. The phycocyanin-treated cells were also stained with Annexin V-FITC to detect any apoptosis and necrosis. Results: Following the MTT assay, the number of living HT-29 cells significantly decreased, with no toxic effect on HUVEC cells. RT-PCR results indicated a significant increase in PTEN and Bax expressions in HT-29 cells due to treatment with phycocyanin, while there was no change in the expression of Bcl-2 and AKT. Flow cytometry on HT-29 cells showed induction of apoptosis and necrosis in 8.79% and 2.9% of cells, respectively, while no necrosis or apoptosis was observed in normal cells. Conclusion: Phycocyanin has a potential for treating colon cancer by affecting AKT/PTEN and Bax/Bcl- 2 and inducing apoptotic genes (Bax and PTEN) while having minimal side effects. Therefore, it could be a promising therapeutic agent for colon cancer. [ABSTRACT FROM AUTHOR]