Synergistic effect of docetaxel combined with cisplatin on inhibiting human osteosarcoma in nude mice

Cisplatin (CDDP) has been shown to be a promising anticancer drug that is effective against many types of cancer, which include osteosarcoma (OS). However, its therapeutic application is restricted by its toxicity in normal tissues, side effects caused in patients, and chemotherapy resistance. Thus, to further improve patients' treatment, the development of novel, more effective and well tolerated therapeutic approaches against OS in clinical is urgent and important. In the present study, nude mice were inoculated subcutaneously with injections of HOS8603 cells, CDDP and docetaxel (DTX) were administered intraperitoneally respectively. The inhibitive effects and the side effects were observed. Tumor weights and volumes were significantly lower and the tumor inhibition rate was significantly higher in the combination group than those of either drug alone or vehicle. The cell density in the tumor tissue was significantly decreased, apoptotic and necrotic cell death was significantly increased in the combination group, as compared with those of either drug alone or vehicle. In addition, there was no obvious side effect happening besides the appearance of erythema and papules in some mice. These results suggest that the combined effects of CDDP and DTX on the growth of human OS in vivo were superior to the single effects. CDDP combined with DTX had synergistic effects at lower concentrations and promoted apoptosis, but did not increase the side effects of chemotherapy.