The Use of β-Elemene to Enhance Radio Sensitization of A375 Human Melanoma Cells

Melanoma is the most malignant and severe type of skin cancer. It is a tumor with a high risk of metastasis and resistant to conventional treatment methods (surgery, radiotherapy, and chemotherapy). β-elemene is the most active constituent of Curcuma wenyujin which is a non-cytotoxic antitumor drug, proved to be effective in different types of cancers. The study aimed to investigate the therapeutic effects of β-elemene in combination with radiotherapy on A375 human melanoma. In this experimental study, human melanoma cells were grown in the monolayer culture model. The procedure of the treatment was performed by the addition of different concentrations of β-elemene to the cells. Then, the cells were exposed to 2 and 4 Gy X-ray in different incubation times (24, 48, and 72 hours). The MTT assay was used for the determination of the cell viability. To study the rate of apoptosis response to treatments, the Annexin V/PI assay was carried out. The results of the MTT assay showed β-elemene reduced the cell proliferation in dose- and time-dependent manners in cells exposed to radiation. Flow cytometry analysis indicated that β-elemene was effective in the induction of apoptosis. Furthermore, the combination treatment with radiation remarkably decreased the cells proliferation ability and also enhanced apoptosis. For example, cell viability in a group exposed to 40 µg/ml of β-elemene was 80%, but combination treatment with 6 MV X beam at a dose of 2 Gy reduced the viability to 61%. Our results showed that β-elemene reduced the proliferation of human melanoma cancer cell through apoptosis. Also, the results demonstrated that the radio sensitivity of A375 cell line was significantly enhanced by β-elemene. The findings of this study indicated the efficiency of β-elemene in treating melanoma cells and the necessity for further research in this field.