Objective: Chemotherapy is effective for treating malignant melanoma, but drug resistance and occurrence of side effects limited this strategy. The balance between autophagy and apoptosis has an essential role in the chemotherapy of cancers. The present investigation aims to examine the efficacy of pogostone (isolated from Pogostemon cablin L.) on the ratio of apoptosis and autophagy caused by dacarbazine in melanoma cells.

Materials and Methods: Human melanoma cells were exposed to different concentrations of dacarbazine and pogostone, and the IC50 values were calculated. The cells were treated with two concentrations higher and lower than IC50 simultaneously, and the dose reduction index and combination index (CI) parameters were calculated. The occurrence of apoptosis and autophagy was evaluated. The expression level of genes related to apoptosis and autophagy pathways was tested.

Results: Pogostone and dacarbazine declined the number of the cells in a dose and time-dependent manner and showed a synergistic effect. There was a significant decrease in autophagy in the co-treatment besides the dacarbazine alone (p < 0.05). There was a considerable increment in apoptosis in cultures treated with pogostone and dacarbazine (p < 0.05). Also, Real-time PCR data confirmed the obtained results.

Conclusions: Pogostone reduced melanoma cell resistance to dacarbazine via autophagy blockage.