title: The effects of 1,25-dihydroxyvitamin D3 on colon cancer cells depend on RhoA-ROCK-p38MAPK-MSK signaling.
abstract: Many studies support a protective action of vitamin D against colon cancer. 1alpha,25-dihydroxyvitamin D3 (1,25(OH)2D3) exerts wide gene regulatory effects in human colon cancer cells. We previously reported that 1,25(OH)2D3 increases cytosolic Ca2+ concentration and transiently activates RhoA and its effector the Rho-associated coiled-kinase (ROCK), and later p38MAPK-MSK. We found that the inhibition of ROCK signaling by Y27632 or that of MSK by Ro318220 prevent the formation of epithelioid islands of SW480-ADH cells by 1,25(OH)2D3 and disrupts the adhesive phenotype of HT29 cells. ROCK and MSK inhibition also abrogates the induction of 1,25(OH)2D3 24-hydroxylase (CYP24), E-cadherin, and vinculin and the repression of cyclin D1 by 1,25(OH)2D3. Moreover, 1,25(OH)2D3 does not promote the localization of the tight junction protein occludin at the plasma membrane in cells expressing a dominant negative RhoA (N19-RhoA). In addition, 1,25(OH)2D3 specifically increases the level of the cysteine protease-inhibitor cystatin D, whereas that of cystatin SN is unaffected. The increase of cystatin D protein caused by 1,25(OH)2D3 is abrogated in N19-RhoA cells. Thus, activation of the RhoA-ROCK-p38MAPK-MSK signaling pathway is essential for the regulation of the phenotype and of the CST5/cystatin D candidate tumor suppressor and other target genes by 1,25(OH)2D3 in colon cancer cells.
authors.affiliation: Instituto de Investigaciones Biomédicas Alberto Sols, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid, and Hospital Universitario Puerta de Hierro, Arturo Duperier 4, 28029 Madrid, Spain.
authors.forename: Paloma
authors.initials: P
authors.lastname: Ordóñez-Morán
authors.forename: Silvia
authors.initials: S
authors.lastname: Alvarez-Díaz
authors.forename: Noelia
authors.initials: N
authors.lastname: Valle
authors.forename: María Jesús
authors.initials: MJ
authors.lastname: Larriba
authors.forename: Félix
authors.initials: F
authors.lastname: Bonilla
authors.forename: Alberto
authors.initials: A
authors.lastname: Muñoz
mesh_terms: D002117:Calcitriol / Q000378:metabolism*; D045744:Cell Line, Tumor; D002462:Cell Membrane / Q000378:metabolism; D049109:Cell Proliferation; D003110:Colonic Neoplasms / Q000378:metabolism*; D019938:Cyclin D1 / Q000378:metabolism; D015891:Cystatins / Q000378:metabolism*; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008565:Membrane Proteins / Q000378:metabolism; D018613:Microscopy, Confocal / Q000379:methods; D062793:Occludin; D038744:Ribosomal Protein S6 Kinases, 90-kDa / Q000378:metabolism*; D015398:Signal Transduction; D019108:Tight Junctions / Q000378:metabolism; D048051:p38 Mitogen-Activated Protein Kinases / Q000378:metabolism*; D054460:rho-Associated Kinases / Q000378:metabolism*; D020742:rhoA GTP-Binding Protein / Q000378:metabolism*
chemical_list: D015891:Cystatins; D008565:Membrane Proteins; C568985:OCLN protein, human; D062793:Occludin; C066737:RHOA protein, human; D019938:Cyclin D1; C071378:CST5 protein, human; D038744:Ribosomal Protein S6 Kinases, 90-kDa; C116919:mitogen and stress-activated protein kinase 1; D054460:rho-Associated Kinases; D048051:p38 Mitogen-Activated Protein Kinases; D020742:rhoA GTP-Binding Protein; D002117:Calcitriol