title: Melanocortin 1 receptor regulates melanoma cell migration by controlling syndecan-2 expression.
abstract: The melanocortin 1 receptor (MC1R), a key regulator of melanogenesis, is known to control inflammation, acting in concert with the MC1R ligand α-melanocyte-stimulating hormone. Although cell migration is a key event in inflammation, few studies have addressed the function of MC1R in this context. Using highly motile melanoma cells, we found that the expression level of MC1R was associated with the extent of migration of mouse melanoma cells, suggesting that MC1R plays a functional role in controlling this migration. Overexpression of MC1R enhanced melanoma cell migration, whereas the opposite was true when MC1R levels were knocked down using small inhibitory RNAs. Interestingly, MC1R expression enhanced the synthesis of syndecan-2, a cell surface heparan sulfate proteoglycan known to be involved in melanoma cell migration. Knockdown of syndecan-2 expression decreased MC1R-mediated cell migration. Further, MC1R inhibited the activation of p38 MAPK, subsequently enhancing expression of sydnecan-2, in parallel with an increase in the extent of cell migration. Consistently, activation of p38 by H(2)O(2) inhibited syndecan-2 expression and cell migration, whereas inhibition of p38 activation enhanced syndecan-2 expression and cell migration. Finally, we found that α-melanocyte-stimulating hormone inhibited MC1R-mediated cell migration via activation of p38 and inhibition of syndecan-2 expression. Together, the data strongly suggest that MC1R regulates melanoma cell migration via inhibition of syndecan-2 expression.
authors.affiliation: Department of Life Sciences, Division of Life and Pharmaceutical Sciences and the Center for Cell Signaling & Drug Discovery Research, Ewha Womans University, Seoul 120-750, Korea.
authors.forename: Heesung
authors.initials: H
authors.lastname: Chung
authors.forename: Jung-hyun
authors.initials: JH
authors.lastname: Lee
authors.forename: Dayun
authors.initials: D
authors.lastname: Jeong
authors.forename: Inn-Oc
authors.initials: IO
authors.lastname: Han
authors.forename: Eok-Soo
authors.initials: ES
authors.lastname: Oh
mesh_terms: D000818:Animals; D045744:Cell Line, Tumor; D002465:Cell Movement; D004789:Enzyme Activation / Q000187:drug effects / Q000235:genetics; D015972:Gene Expression Regulation, Neoplastic; D055785:Gene Knockdown Techniques; D006801:Humans; D006861:Hydrogen Peroxide / Q000494:pharmacology; D008545:Melanoma / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D051379:Mice; D009363:Neoplasm Proteins / Q000235:genetics / Q000378:metabolism*; D016877:Oxidants / Q000494:pharmacology; D044102:Receptor, Melanocortin, Type 1 / Q000235:genetics / Q000378:metabolism*; D053669:Syndecan-2 / Q000096:biosynthesis* / Q000235:genetics; D000521:alpha-MSH / Q000235:genetics / Q000378:metabolism; D048051:p38 Mitogen-Activated Protein Kinases / Q000235:genetics / Q000378:metabolism
chemical_list: D009363:Neoplasm Proteins; D016877:Oxidants; D044102:Receptor, Melanocortin, Type 1; C508245:SDC2 protein, human; C508246:Sdc2 protein, mouse; D053669:Syndecan-2; D000521:alpha-MSH; D006861:Hydrogen Peroxide; D048051:p38 Mitogen-Activated Protein Kinases