Celastrus orbiculatus Celastraceae Thunb extracts inhibit proliferation and migration of oral squamous cell carcinoma cells by blocking NF-κB pathway

Purpose: To investigate the mechanism of action of Celastrus orbiculatus extract (COE) on oral squamous carcinoma cells. Methods: Tca8113 cells were divided into negative control and three COE treatment groups, viz, 20, 40, and 80 μg/mL of COE. Succinate dehydrogenase activity assay (MTT assay) and flow cytometry were used to assess cell proliferation and apoptosis. Cell migration and invasion were assessed by Transwell chamber and wound healing assays while relative protein expression was determined by Western blot. Results: As the concentration of COE increased, the number of cells arrested in the G0/G1 phase increased (p < 0.05), expressions of cell-cycle-related proteins decreased (p < 0.001); the number of apoptotic cells increased (p < 0.001), and the rates of cell migration and invasion decreased (p < 0.001). Exogenous COE significantly inhibited p-IκBα accumulation in the cytoplasm and induced IκBα accumulation. Nuclear p65 recruitment was reduced in cells treated with COE compared to untreated control cells (p < 0.001), suggesting that the classical NF-κB pathway was blocked by COE. Conclusion: These results demonstrate that COE inhibits the proliferation and migration of oral squamous cell carcinoma cells while promoting apoptosis by blocking NF-κB pathway. These findings suggest that Celastrus orbiculatus extract possesses a potential therapeutic effect on oral squamous cell carcinoma.