Cinobufacini Inhibits Proliferation of Human Caski Cervical Cancer Cells by Inducing Apoptosis

Objective: To investigate the effects of cinobufacini on proliferation and apoptosis in human Caski cervical cancer cells. Method: MTT assay was used to assay cell proliferation; the flow cytometry assay was used to determine cell cycle; DNA fragmentation assays was used to evaluate apoptosis; western blot was used to analyze cytochrome c content in the cytosol; the level of reactive oxygen species( ROS) was determined by fluorescence histochemistry; the mitochondrial membrane potential was determined by Dioc6- staining method. Result: Cinobufacini inhibited proliferation of Caski cells significantly in the time- and dose- dependent manners. The median inhibition concentration( IC50) at 48h is 1. 68μg/mL. Cinobufacini treatment resulted in DNA fragmentation,elevated ROS levels,increased release of cytochrome C from mitochondria to the cytosol and decreased mitochondrial membrane potential. In the same time,cinobufacini inhibited cell division and arrested Caski cells at the G2 / M phase. Conclusion: Cinobufotalin significant inhibit proliferation of Caski cells. The underlying mechanism is associated with increased ROS generation,which induced endogenous apoptosis and inhibited cell division. The results of this study suggest that cinobufacini has a potential value for the clinical treatment of cervical cancer.