Further evidence to support the melanocytic origin of MDA-MB-435.

BACKGROUND/AIMS Until recently, the cell line MDA-MB-435 was widely accepted as originating from a breast cancer. However, microarray derived data have suggested that this cell line may in fact originate from an occult melanoma. This study was designed to investigate this hypothesis further. METHODS Quantitative reverse transcription polymerase chain reaction and immunohistochemistry were used to investigate the tissue of origin of two sublines of MDA-MB-435 (MDA-MB-435 S and MDA-MB-435 HGF). The expression of a panel of genes typical of breast cells or melanocytes was analysed. RESULTS The MDA-MD-435 cell lines expressed none of the genes characteristic of breast cancer cells but did express several genes commonly expressed by melanocytes. CONCLUSIONS These results strongly suggest that MDA-MB-435 is indeed of melanoma origin.