Effects of heavy ions (12C6+) on malignant melanoma B16F10 cells

Background: This study aimed to investigate the effects of heavy ion (12C6+) irradiation on the proliferation, apoptosis, cell cycle, migration, and epithelial-mesenchymal transition (EMT) of B16F10 cells. Methods: The B16F10 cells, which is a malignant melanoma cell line widely used in research, irradiated by 12C6+ and X-ray were detected by Hoechst 33342/propidium iodide double staining, Western blot, flow cytometry, and cell scratch tests to evaluate cell proliferation, expression of apoptosis related proteins, G2/M phase arrest, cell migration, cell invasion and EMT. Results: Compared with the same physical X-ray dose, 12C6+ could effectively inhibit the proliferation of B16F10 cells, inhibit the expression of B-cell lymphoma-2 (Bcl-2) and cellular-myelocytomatosis viral oncogene (c-Myc), and induce the expression of Bax to promote the apoptosis of B16F10 cells. After 12C6+ irradiation, the B16F10 cells exhibited G2/M phase arrest. B16F10 cells were highly sensitive to 12C6+ irradiation. Moreover, compared with X-ray, the 12C6+ irradiation significantly inhibited the migration of B16F10 cells and inhibited extracellular matrix cleavage, induced E-cadherin expression, enhanced cell adhesion, and further inhibited cell invasion, migration, and EMT. Conclusions: The B16F10 cells were highly radiosensitive to 12C6+. Compared with X-ray, B16F10 cells irradiated by 12C6+ significantly reduced the expressions of matrix metalloproteinases to inhibit extracellular matrix cleavage and, thus, effectively inhibit cell invasion and metastasis. However, although the issue of the different therapeutic effects of heavy ion and X-ray radiotherapy on malignant melanoma was investigated and preliminary research results were obtained, several problems must be further studied.