NRN1 and melanoma: Melanoma cells synthesize NRN1 in higher amounts than melanocytes from different donors and in different passages (NHEM P2/P4/P6), as shown by qRT-PCR on nine primary and thirteen metastatic melanoma cell lines (Figure 1A), western blot analysis of protein lysates of sixteen melanoma cell lines (Figure 1B), and immunofluorescence staining of three melanoma cell lines (Figure 1C).