Characterization of a new human melanoma cell line with CD133 expression.

A novel human malignant melanoma cell line, designated MEL-RC08, was established from a pericranial metastasis of a malignant melanoma of the skin. The cell line has been subcultured for more than 150 passages and is tumorigenic in nude mice. Growth kinetics, cytogenetics, flow cytometry, and molecular techniques for analysis of the genes implicated in cell cycle control; mutations in BRAF, NRAS, C-KiT, RB, and TP53 genes; and amplification of MDM2, CDK4, and cyclin D1 have been studied. Cytogenetically, the tumor and the cell line showed a hypertriploid karyotype with many clonal numeric and structural abnormalities. DNA flow cytometry showed an aneuploid peak with a DNA index value of 1.5. Mutations in TP53 and BRAF genes were demonstrated in both tumor and cell line. Furthermore, stem cell marker CD133 expression was detected in most cells, together with other stem cell markers, suggesting the presence of cells with tumor-initiating potential in this cell line.