MCAM and melanoma: However, ectopic overexpression of CD146 by lentivirus transfection (MG63-2) did not significantly increase the number of MG63 cells (MTT: F = 4.192, P = 0.601, Fig. 2B; cell count: F = 2.764, P = 0.172, Additional file 1: Fig. S4A), nor did it in melanoma [6].