CREB1 and melanoma: SNA077, a crude extract of marine Streptomyces sp., has the potential to act as a potent and effective whitening agent, as it was shown to inhibit melanogenesis in the MNT-1 human melanoma cell line and in the mouse melanocyte cell lines Melan-a and B16 by downregulating melanogenic proteins in the cAMP/PKA (protein kinase A)/CREB (cAMP response element-binding protein) signaling pathway [15].