Abstract:Objective: Hyperthermia is an attractive addition to multidisciplinary approaches to clinical cancer treatment.The efficiency of hyperthermia depends on the elevation of the temperature and the duration of treatment. It has been reported that in vitro and in vivo hyperthermia enhanced the cytotoxic effect of certain anticancer drugs. However, this enhancement varies,depending on the drug used and the scheduling of treatments. Thus, the combination effect of chemotherapy and hyperthermia remains unclear. In this study, we aimed to investigate whether concurrent exposure of human hepatocellular carcinoma cells SMMC-7721 to chemotherapeutic agents andhypenhermia could increase anticancer effects. Methods: Two chemotherapeutic agents, cisplatin and hydroxycamptothecin, were applied. The MTT assay was performed to evaluate the growth inhibition of SMMC-7721 induced by anticancer drugs with and without hyperthermia. Flow cytometric analysis was used for the assessment of apoptosis after treatments. Results: The percentages of growth inhibition of SMMC-7721 induced by cisplatin (10 μg/ml) alone,hydroxycamptothecin (1 μg/ml) alone, hyperthermia alone, cisplatin and hyperthermia, hydroxycamptothecin and hyperthermia,were 20.77﹪, 13.65﹪, 32.46﹪, 62.76﹪, 71.89﹪, respectively. The percentages of apoptosis of five treatments are 5.56﹪,3.96﹪, 10.16﹪, 24.32﹪, 20.42﹪, respectively. Conclusion: While both hyperthermia and anticancer drugs can individually induce apoptosis and anti-proliferation effect, the combination of the two treatments induce significantly higher apoptosis and cytotoxicity than hyperthermia or anticancer drugs treatment alone. These data suggest a synergistic benefit when hyperthermia and anticancer drugs used concurrently.