Experimental study on caffeine and cisplatin induction apoptosis of osteosarcoma cell line(OS-732)

Objective To investigate the effect of caffeine and cisplatin induced apoptosis of osteosarcoma cell line(OS-732), and to explore the potential mechanism of caffeine enhancing cytotoxic effect of cisplatin in osteosarcoma cell line. Methods The OS-732 cell line was cultured for 72 hours; treated with caffeine, cisplatin and caffeine combined with cisplatin for 72 hours respectively, the apoptosis rates of OS-732 cell line were analysed by flow cytometry. Mitochondrial transmembranous potentials were measured by cellular rhodamine 123 stain on flow cytometry. Apoptosis was assessed by electron microscope at 80 kV. Results The OS-732 cell line was cultured for 72 hours; treated with caffeine (5.0 mmol/L ), cisplatin (10.0 μg/ml ) and caffeine (5.0 mmol/L ) combined with cisplatin (10.0 μg/ml) for 72 hours respectively. The apoptosis rates were 2.50%, 10.62%, 31.62% and 57.44% respectively. The percentage of decline of mitochondrial transmembranous potentials were 8.12%, 26.45%, 17.82% and 38.26% respectively. Electron microscope revealed the characteristic apoptosis alterations,such as shrinking cellular chromatin condensation, crescent nucleus, cytoplasmic vacuoles and so on. Conclusion Caffeine and cisplatin can induce apoptosis of osteosarcoma cell line(OS-732), while the cell line treated with caffeine and cisplatin simultaneously, the apoptosis rate was increased obviously. The induction of apoptosis of osteosarcoma cell line by caffeine may be one of potential mechanism enhancing cytotoxic effect of cisplatin in osteosarcoma cell line.