title: Amino acid limitation induces down-regulation of WNT5a at transcriptional level.
abstract: An aberrant WNT signaling contributes to the development and progression of multiple cancers. WNT5a is one of the WNT signaling molecules. This study was designed to test the hypothesis that amino acid deprivation induces changes in the WNT signaling pathway in colon cancer cells. Results showed that targets of the amino acid response pathway, ATF3 and p21, were induced in the human colon cancer cell line SW480 during amino acid limitation. There was a significant decrease in the WNT5a mRNA level following amino acid deprivation. The down-regulation of WNT5a mRNA by amino acid deprivation is not due to mRNA destabilization. There is a reduction of nuclear beta-catenin protein level by amino acid limitation. Under amino acid limitation, phosphorylation of ERK1/2 was increased and the blockage of ERK1/2 by the inhibitor U0126 partially restored WNT5a mRNA level. In conclusion, amino acid limitation in colon cancer cells induces phosphorylation of ERK1/2, which then down-regulates WNT5a expression.
authors.affiliation: Department of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA.
authors.forename: Zuguang
authors.initials: Z
authors.lastname: Wang
authors.forename: Hong
authors.initials: H
authors.lastname: Chen
mesh_terms: D000596:Amino Acids / Q000378:metabolism*; D002070:Butadienes / Q000494:pharmacology; D045744:Cell Line, Tumor; D002467:Cell Nucleus / Q000378:metabolism; D003110:Colonic Neoplasms / Q000235:genetics / Q000378:metabolism*; D015536:Down-Regulation; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D019950:Mitogen-Activated Protein Kinase 1 / Q000037:antagonists & inhibitors / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3 / Q000037:antagonists & inhibitors / Q000378:metabolism; D009570:Nitriles / Q000494:pharmacology; D010766:Phosphorylation; D047428:Protein Kinase Inhibitors / Q000494:pharmacology; D011518:Proto-Oncogene Proteins / Q000235:genetics*; D020871:RNA Stability; D012333:RNA, Messenger / Q000378:metabolism; D014158:Transcription, Genetic; D051153:Wnt Proteins / Q000235:genetics*; D000071818:Wnt-5a Protein; D051176:beta Catenin / Q000378:metabolism
chemical_list: D000596:Amino Acids; D002070:Butadienes; D009570:Nitriles; D047428:Protein Kinase Inhibitors; D011518:Proto-Oncogene Proteins; D012333:RNA, Messenger; C113580:U 0126; C085389:WNT5A protein, human; D051153:Wnt Proteins; D000071818:Wnt-5a Protein; D051176:beta Catenin; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3