[Cytotoxic effect of thermo-chemotherapy with cisplatin on osteosarcoma OS-732 cell line]

To observe the cytotoxic effect of thermo-chemotherapy with cisplatin on osteosarcoma OS-732 cell line and to explore its mechanism.

The osteosarcoma OS-732 cell line was treated with different temperature, cisplatin alone and 43 degrees C +cisplatin for 1 h, respectively and the in vitro cytotoxic effect was observed with MTT assay. The cell cycle and the apoptotic rate were analyzed with flow cytometry (FCM); the cellular apoptosis was observed also with electron microscope.

The cytotoxicity index increase markedly as the temperature elevated or the concentration of cisplatin increased. While treated with 43 degrees C hyperthermia and cisplatin simultaneously, the cytotoxicity index increased to 72.37%;the cell cycle of the treated OS-732 cells line was changed with marked increase in S phase and decreasing in G(2)/M phase. The apoptotic rate increased markedly with the highest of 56.47%. Electron microscope showed the characteristic apoptotic alterations.

Hyperthermia with cisplatin enhance cytotoxicity on osteosarcoma OS-732 cell line and the induced cell apoptosis may be one of the mechanisms of enhanced cytotoxicity by thermo-chemotherapy.