We used RT-PCR analysis to characterize the NODAL expression in a panel of human cell lines relevant to cancer and melanoma: melanocytes, non-metastatic melanoma (MNT1), metastatic melanoma (A375M–noted A375 in the rest of the study, FO1, 888 Mel, SLM8), breast cancer (MCF7), and embryonic kidney (HEK293). This evidence concerns the gene NODAL and metastatic melanoma.