Investigating the Effect of Photodynamic Therapy Pretreatment on Increasing the Sensitivity to Cisplatin and Inducing Apoptosis in Ovarian Cancer Cells SKOV-3

Abstract

Introduction: The chemotherapy drug cisplatin, recognized as one of the most common treatments for ovarian cancer, is associated with significant side effects and drug resistance. Among the strategies employed to reduce toxicity and drug resistance are targeted drug delivery and combination therapies, such as photodynamic therapy. Materials and methods: Ovarian cancer SKOV-3 cells were treated with cisplatin and photodynamic therapy, separately and in combination. The MTT assay was used to assess cell viability in these groups. Flow cytometry was employed to evaluate the extent of apoptosis induction and cell cycle arrest. The scratch and colony formation assays were used to examine the inhibition of cell migration and colony formation, respectively. To assess changes in the expression of genes involved in apoptosis, cell migration, and stemness properties, qRT-PCR was utilized. Results: The MTT assay results indicated an increased sensitivity of cells to cisplatin in the combination treatment. In the apoptosis assay, the percentage of cell death was significantly higher in the combination treatment group. Cell cycle arrest was observed at the sub-G1, S, and G2-M phases in the combination treatment group. The scratch and colony formation assays demonstrated reduced cell migration and colony formation in the combination treatment groups. Gene expression changes related to apoptosis, including caspase-3, caspase-9, and Bcl-2, indicated an increase in apoptosis in the combination treatment group. Moreover, more significant changes in the expression of genes involved in cell migration, such as MMP-9 and MMP-3, and genes related to stemness, including SOX2, CD44, and CD133, were observed in the combination treatment group compared to cisplatin or photodynamic therapy alone. Conclusion: The results demonstrated that combining photodynamic therapy and cisplatin can induce apoptosis and reduce cell migration in ovarian cancer cells. Therefore, it can be concluded that the initial treatment of SKOV-3 cells with photodynamic therapy enhances their sensitivity to cisplatin. This combination therapy could be a highly promising approach for the treatment of ovarian cancer. Keywords: Ovarian Cancer, Photodynamic Therapy, Cisplatin, Combination Therapy