Anticancer activity of sinapic acid by inducing apoptosis in HT-29 human colon cancer cell line

Colorectal cancer is the third most lethal and fourth most commonly diagnosed cancer worldwide. Sinapic acid, a derivative of hydroxycinnamic acid, is a promising phytochemical exhibiting numerous pharmacological activities in various systems. It is a substantial chain-breaking antioxidant that operates as a radical scavenger. The aim of this research was to investigate the antiproliferative effect of sinapic acid on the HT-29 cell line besides the mechanisms underlying this activity. The effect of sinapic acid on the viability of HT-29 cell line was investigated using XTT assay. The levels of BCL-2, cleaved caspase 3, BAX, cleaved PARP, and 8-oxo-dG were measured using ELISA. Gamma-H2AX and cytochrome c expressions were assessed semiquantitatively using immunofluorescence staining. Sinapic acid at 200 µm and higher doses produced a significant antiproliferative effect on HT-29 cells. The IC50 value was found to be 317.5 µm for 24 h. Sinapic acid (317.5 µm) significantly elevated cleaved caspase 3, BAX, cleaved PARP, and 8-oxo-dG levels. The levels of gamma-H2AX foci are significantly higher, while the levels of cytochrome c are lower in sinapic acid-treated HT-29 cells. These results indicate that sinapic acid has antiproliferative, apoptotic, and genotoxic effects on colon cancer cells.