Investigation of cytotoxic and genotoxic effects of olive leaf extract on colon cancer cells and normal cell lines

Colon cancer is a type of cancer that occurs when cells in the mucous layer membrane that surrounds the inner surface of the large intestine sections multiply unevenly. This study aimed to investigate olive leaf extract's cytotoxic and genotoxic effects on HTC-116 colon cancer cell lines and HDF healthy cell lines. In the study, olive leaf extract was prepared in methanol. The passaged HTC-116 and HDF cell lines were then incubated in Dulbecco's Modified Eagle's Medium (DMEM). Olive leaf extract extracted in methanol was applied to these cell lines at 3, 10, 20, 50, and 80 μg/ml and left for incubation for 24 hours. Then, the cytotoxic effect was determined by MTT analysis. The genotoxic effect of olive leaf extracts applied to HTC-116 and HDF cell lines after a 24-hour incubation period was determined by Hoechst stain. DNA damage was visualized with a DAPI filter on a camera-attached trinocular fluorescence microscope 30 minutes after staining with Hoechst. The MTT analysis revealed that the cytotoxic effects of olive leaf extract applied to the HTC-116 cell line were close to each group after the 24-hour incubation period. As a result of the examination of the genotoxic activity with Hoechst DNA staining in colon cancer cells (HCT-116), olive leaf extract at various concentrations treated to the cell line had a minor genotoxic effect at low doses (3, 10, and 20 μg/ml), while at high concentrations (50 and 80 μg). /ml), the genotoxic effects of the applications were determined. In examining the genotoxic impact of Hoechst DNA staining in the HDF cell line, no genotoxic effect was observed at low doses (3, 10, and 20 μg/ml) of olive leaf extract applied to the cell line at various doses. The little genotoxic effects of high doses (50 and 80 μg/ml) were also observed. Olive leaf contains phenolic substances and has antioxidant, antimicrobial, antiinflammatory, antiatherogenic, anticarcinogenic and antiviral effects.Keywords: In vitro culture, plant regeneration, callus, hormones.