RESUMO
OBJECTIVES: Grape seed oil (GSO) has recently gained popularity due to its anticancer properties. This study aimed to investigate the efficacy of combining cisplatin (CP) and GSO in tongue squamous cell carcinoma (TSCC) treatment. METHODS: In this study, human tongue carcinoma cell line (HNO-97) was treated with CP and GSO alone or in combination. The effects of CP and GSO on cytotoxicity and cell cycle arrest were studied using the MTT assay and flowcytometry, respectively. The apoptotic markers, including p53 and caspase 8, were assessed using reverse-transcription polymerase chain reaction (RT-PCR), caspase 3 using immunohistochemistry, and the angiogenic marker vascular endothelial growth factor (VEGF) using enzyme-linked immunosorbent assay (ELISA). RESULTS: The IC50 drug concentrations were found to be 16.4 ug/mL of GSO and 2.18 ug/mL of CP. When compared to the untreated control group, the percentage of S phase cells and apoptotic cells was significantly higher in the GSO, CP, and GSO/CP combination therapy groups. Furthermore, p53, caspase 8, caspase 3 expression were significantly upregulated in the GSO-and CP-treated groups, with evident upregulation with GSO/CP combination therapy. However, VEGF levels were significantly lower in the GSO-, CP-, and combined GSO/CP-treated groups. CONCLUSIONS: GSO has both an apoptotic and antiangiogenic effect in the treatment of TSCC, suggesting a new strategy for phytochemical-based combination therapy.