title: Epigenetic regulation of maspin expression in the human placenta.
abstract: Maspin, a tumour suppressor gene, is differentially expressed in the human placenta. Decreased expression of maspin in the first trimester corresponds with the period of maximum trophoblast invasion, suggesting a role in cell invasion and motility. Although methylation of CpG islands regulates maspin expression in cancer cells, the mechanism of maspin regulation in the human placenta is unknown. Our objectives were to determine the role of epigenetic alterations in the regulation of maspin expression in the placenta. Placental samples obtained from 7 to 40 weeks' gestation were used for bisulphite sequencing and chromatin immunoprecipitation (ChIP) PCR. There was no significant change in the methylation indices in the promoter region of maspin throughout gestation. The levels of histone modifications associated with transcriptionally active chromatin were significantly different in placental tissues from second and third trimester relative to those from first trimester. Addition of trichostatin A (TSA) to placental explants increased the maspin mRNA expression (8- to 20-fold), whereas addition of 5-aza-cytidine (5-AzaC) had no effect on maspin expression. Our data suggest that maspin expression in the human placenta is regulated by changes in histone tail modifications. This is the first report of selective histone modifications associated with differential placental gene expression in human gestation.
authors.affiliation: Department of Obstetrics and Gynecology, University of Iowa Roy J. and Lucille A. Carver College of Medicine, Iowa City, IA, USA.
authors.forename: Anuja
authors.initials: A
authors.lastname: Dokras
authors.forename: Jeremy
authors.initials: J
authors.lastname: Coffin
authors.forename: Lorie
authors.initials: L
authors.lastname: Field
authors.forename: Amanda
authors.initials: A
authors.lastname: Frakes
authors.forename: Hwahyung
authors.initials: H
authors.lastname: Lee
authors.forename: Anuradha
authors.initials: A
authors.lastname: Madan
authors.forename: Timothy
authors.initials: T
authors.lastname: Nelson
authors.forename: Gi-Yung
authors.initials: GY
authors.lastname: Ryu
authors.forename: Jae-Geun
authors.initials: JG
authors.lastname: Yoon
authors.forename: Anup
authors.initials: A
authors.lastname: Madan
mesh_terms: D000107:Acetylation; D001374:Azacitidine / Q000494:pharmacology; D002478:Cells, Cultured; D002843:Chromatin / Q000378:metabolism; D018899:CpG Islands; D019175:DNA Methylation; D004791:Enzyme Inhibitors / Q000494:pharmacology; D044127:Epigenesis, Genetic / Q000187:drug effects; D005260:Female; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects; D016147:Genes, Tumor Suppressor; D005865:Gestational Age; D056572:Histone Deacetylase Inhibitors; D006655:Histone Deacetylases / Q000378:metabolism; D006657:Histones / Q000378:metabolism; D006801:Humans; D006877:Hydroxamic Acids / Q000494:pharmacology; D010920:Placenta / Q000187:drug effects / Q000378:metabolism*; D011247:Pregnancy; D011401:Promoter Regions, Genetic; D015843:Serpins / Q000235:genetics / Q000378:metabolism*
chemical_list: D002843:Chromatin; D004791:Enzyme Inhibitors; D056572:Histone Deacetylase Inhibitors; D006657:Histones; D006877:Hydroxamic Acids; C085344:SERPIN-B5; D015843:Serpins; C012589:trichostatin A; D006655:Histone Deacetylases; D001374:Azacitidine