Enhancement of Cisplatin Efficacy by Gold Nanoparticles or Microwave Hyperthermia? An In Vitro Study on a Melanoma Cell Line

Purpose: Chemotherapy-resistance of melanoma has led to poor prognosis and decreased survival in the patients. Therefore, the addition of adjuvant therapies to the conventional chemotherapy regimens has been taken into consideration to improve the clinical treatments efficiency. In this study, the effect of microwave (MW) Hyperthermia has been evaluated on the toxicity of cisplatin on the MM200 cell line in the presence and without gold nanoparticles (GNPs). Methods: Cells incubation was performed with and without cisplatin in the presence and absence of GNPs. To induce hyperthermia, the cells were immediately placed under MW irradiation for 25 and 30 minutes (4143°C) following the addition of the drug and GNPs, then they were incubated for 24 hours. Finally, cell survival was determined by MTT assay. Results: GNPs (up to 6.6 μg/mL) showed no toxicity. GNPs at the concentration of 13.2 and 26.4 μg/mL caused 13% and 20.7% drop in cell survival rate, respectively. IC50 of cisplatin decreased from 4 to 2 μg/mL in the presence of GNPs. Hyperthermia (43°C) plus chemotherapy (2 μg/mL) resulted in no significant enhancement in cisplatin cytotoxicity relative to chemotherapy alone whereas by adding GNPs, an increase in cell mortality up to 15-fold in comparison to cisplatin alone was observed. Conclusions: There is a synergistic effect between cisplatin and GNPs, this could be due to the facilitated entrance of cisplatin in the presence of GNPs. MW exposure improves the efficacy of cisplatin therapy in the presence of GNPs on MM200 cells.