Induction of Apoptosis by a Combination of Paclitaxel and Carboplatin in the Presence of Hyperthermia

Purpose: To study enhancing effects of paclitaxel in the thermochemotherapy of osteosarcoma cell lines andrelated mechanisms. Materials and
Methods: Paclitaxel and carboplatin were used alone or jointly on OS732cell lines in the presence of hyperthermia. Inhibition of proliferation was measured by MTT assay and cellularchanges were assessed with inverted phase contrast and fluorescence microscopy. Apoptosis was analyzedwith flow cytometry (FCM) and Fas expression by immunocytochemistry.
Results: At 43℃, one hour after theapplication of 10ug/ml paclitaxel and 5mg/ml carboplatin on OS732 cells jointly, the survival rate was 15.8%which was significantly lower than with 10mg/ml paclitaxel (45.8%) and 5mg/ml carboplatin (47.7%) respectively(P<0.01). Moreover, changes of morphology and apoptotic rates indicated that the apoptosis-inducing effect ofcombined application was also much enhanced, as evident also regarding Fas expression.
Conclusion: Paclitaxelis conducive to thermochemotherapy of osteosarcoma cell lines, possibly accomplished by up-regulation of Fasexpression with induction of apoptosis.