title: Loss of expression and aberrant methylation of the CDH13 (H-cadherin) gene in breast and lung carcinomas.
abstract: Expression of some members of the cadherin family is reduced in several human tumors, and CDH13 (H-cadherin), located on chromosome 16q24.2-3, may function as a tumor suppressor gene. In human tumors, loss of expression of many tumor suppressor genes occurs by aberrant promoter region methylation. We examined the methylation status of the CDH13 promoter in breast and lung cancers and correlated it with mRNA expression using methylation-specific PCR and reverse transcription-PCR. Methylation was frequent in primary breast tumors (18 of 55, 33%) and cell lines (7 of 20, 35%). In lung cancers, methylation was present more frequently in non-small cell lung cancer tumors (18 of 42, 43%) and cell lines (15 of 30, 50%) than in small cell lung cancer cell lines (6 of 30, 20%; P = 0.03). Only the methylated or unmethylated forms of the gene were present in most (73 of 80, 91%) tumor cell lines. CDH13 expression was present in 24 of 30 (80%) of nonmethylated tumor lines. All 18 methylated lines tested lacked expression irrespective of whether the unmethylated form was present, confirming biallelic inactivation in methylated lines. Gene expression was restored in all five methylated cell lines tested after treatment with the demethylating agent 5'-aza-2-deoxycytidine. Our results demonstrate frequent aberrant methylation of CDH13 in breast and lung cancers accompanied by loss of gene expression, although expression may occasionally be lost by other mechanisms.
authors.affiliation: Hamon Center for Therapeutic Oncology Research, University of Texas Southwestern Medical Center, 6000 Harry Hines Boulevard, Dallas, TX 75390, USA.
authors.forename: K O
authors.initials: KO
authors.lastname: Toyooka
authors.forename: S
authors.initials: S
authors.lastname: Toyooka
authors.forename: A K
authors.initials: AK
authors.lastname: Virmani
authors.forename: U G
authors.initials: UG
authors.lastname: Sathyanarayana
authors.forename: D M
authors.initials: DM
authors.lastname: Euhus
authors.forename: M
authors.initials: M
authors.lastname: Gilcrease
authors.forename: J D
authors.initials: JD
authors.lastname: Minna
authors.forename: A F
authors.initials: AF
authors.lastname: Gazdar
mesh_terms: D001943:Breast Neoplasms / Q000235:genetics* / Q000378:metabolism; D015820:Cadherins / Q000096:biosynthesis / Q000235:genetics*; D002289:Carcinoma, Non-Small-Cell Lung / Q000235:genetics / Q000378:metabolism; D018288:Carcinoma, Small Cell / Q000235:genetics / Q000378:metabolism; D019175:DNA Methylation; D004273:DNA, Neoplasm / Q000235:genetics; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D020868:Gene Silencing; D016147:Genes, Tumor Suppressor; D006801:Humans; D019656:Loss of Heterozygosity; D008175:Lung Neoplasms / Q000235:genetics* / Q000378:metabolism; D016133:Polymerase Chain Reaction / Q000379:methods; D011401:Promoter Regions, Genetic; D017422:Sequence Analysis, DNA; D014407:Tumor Cells, Cultured
chemical_list: D015820:Cadherins; D004273:DNA, Neoplasm; C099972:H-cadherin