[Inhibition of the motility of melanoma cells using interference RNA against CD9].

INTRODUCTION Although 65 % of the deaths caused by skin cancer are due to melanomas, the possible causes that may explain the aggressiveness of this type of tumor are still unknown. Different approaches have been used to try to find an effective treatment, but they have been unsuccessful. Interference RNA (iRNA) is an essential technique for this research. With this technique, we can selectively "knock down" or silence protein expression. The tetraspanins CD9 and CD151 are molecules involved in cell motility, including melanoma cells. MATERIAL AND METHODS A375 melanoma cell line, anti-CD9 and anti-CD151 monoclonal antibodies, and iRNA against CD9 and CD151. Immunofluorescence techniques, flow cytometry, cell transfection, cell selection with magnetic beads and evaluation of cell migration in a wound-healing model. RESULTS The A375 cells express CD9 and CD151. By using iRNA against CD9 and CD151, we managed to inhibit the expression of these proteins. The cells transfected with iRNA against CD9 showed significant inhibition of their motility. DISCUSSION We managed to silence the expression of CD9 and CD151 using iRNA techniques in the A375 melanoma cell line. The reduction in CD9 caused the inhibition of cell motility, while the interference with CD151 expression had a more moderate effect. This data indicates that the knockdown of tetraspanins may be a future target for the treatment of melanoma.