Investigation of the effect of thymoquinone on EGFR/FOXP3 signaling pathway in OVCAR3 human ovarian adenocarcinoma cells

Aim: In our study, we aimed to investigate the cytotoxic effects of OVCAR3 human ovarian adenocarcinoma cells and human skin keratinocyte cell line HaCat cells by applying the chemotherapeutic drug doxorubicin (Dox) and the natural anticancer property thymoquinone (TQ). Cancer has become an element that threatens human life at an increasing rate. Studies on the cytotoxic effect of TQ, one of the active components of the Nigella sativa L. (black cumin) plant we used in our study, on ovarian cancer are limited. For this reason, the cytotoxicity of TQ, which has the potential to provide an alternative and support to chemotherapy for the treatment of ovarian cancer, which is an important problem, was investigated through the EGFR/FOXP3 pathway. Material Method: In our study, different doses of Thymoquinone and Doxorubicin were applied to the cells for 24, 48 and 72 hours and the cytotoxicity level was determined by the MTT method. With Western blot and RT-PCR analysis, the metastasis markers EGFR and FOXP3 and the apoptosis marker API5 genes and their expression levels were examined. Colony counting was performed after DAPI staining and its effect on cell proliferation was determined. Applications were carried out by creating an in vitro wound model for metastasis and cell migration was evaluated morphologically. All results were analyzed statistically. Result: As a result of MTT analysis, it was found that cytotoxicity was at the highest level in the TK and Dox applied group, metastasis was prevented especially in the TK and Dox combined group, and RT-PCR analysis showed that the activity in the EGFR and FOXP3 pathway decreased the most with TK and the amount of protein decreased with TK and Dox. Conclusion: The results of the study showed that the highest cytotoxic effect, the highest apoptosis induction, and a significant decrease in EGFR and FOXP3 levels occurred in TK and Dox applications with the application of thymoquinone. Key words: OVCAR3, Thymoquinone, EGFR, FOXP3, Apoptosis, Metastasis.