title: CpG site hypermethylation of E-cadherin and Connexin26 genes in hepatocellular carcinomas induced by a choline-deficient L-Amino Acid-defined diet in rats.
abstract: We investigated DNA methylation patterns of E-cadherin and Connexin26 (Cx26) genes in rat hepatocellular carcinomas (HCCs) induced by a choline-deficient L-Amino Acid-defined (CDAA) diet. Six-wks-old F344 male rats were continuously fed with a CDAA diet for 75 wks, and were then killed. A total of five HCCs were obtained, and genomic DNA was extracted from each HCC for assessment of methylation status in the 5' upstream regions of E-cadherin and Cx26 genes by bisulfite sequencing, comparing to two normal liver tissues. The five HCCs showed highly methylated E-cadherin and Cx26 genes, while these genes in two normal liver tissues were all unmethylated. For analysis of gene expression, real-time quantitative reverse transcription (RT)-polymerase chain reaction (PCR) was performed. Expressions of E-cadherin and Cx26 genes were significantly reduced in the five HCCs (P < 0.0001 and P < 0.001, respectively) compared to normal liver tissues, correlating with their methylation statuses. These results suggested that hypermethylation of E-cadherin and Cx26 genes may be involved in the development of HCCs induced by a CDAA diet in rats.
authors.affiliation: Laboratory of Cancer Biology and Bioinformatics, Department of Life Science, Faculty of Science and Engineering, Kinki University, Higashiosaka, Osaka, Japan.
authors.forename: Toshifumi
authors.initials: T
authors.lastname: Tsujiuchi
authors.forename: Kyoko
authors.initials: K
authors.lastname: Shimizu
authors.forename: Yumi
authors.initials: Y
authors.lastname: Itsuzaki
authors.forename: Mariko
authors.initials: M
authors.lastname: Onishi
authors.forename: Eriko
authors.initials: E
authors.lastname: Sugata
authors.forename: Hiromasa
authors.initials: H
authors.lastname: Fujii
authors.forename: Kanya
authors.initials: K
authors.lastname: Honoki
mesh_terms: D000596:Amino Acids; D000818:Animals; D015820:Cadherins / Q000235:genetics* / Q000378:metabolism; D006528:Carcinoma, Hepatocellular / Q000235:genetics / Q000378:metabolism*; D002796:Choline Deficiency; D000072259:Connexin 26; D017630:Connexins / Q000235:genetics* / Q000378:metabolism; D018899:CpG Islands; D019175:DNA Methylation; D004032:Diet; D015972:Gene Expression Regulation, Neoplastic; D008114:Liver Neoplasms, Experimental / Q000235:genetics / Q000378:metabolism*; D008297:Male; D051381:Rats; D011916:Rats, Inbred F344
chemical_list: D000596:Amino Acids; D015820:Cadherins; D017630:Connexins; C000607044:Gjb2 protein, rat; D000072259:Connexin 26