title: Hypermethylation does not account for the frequent loss of the retinoic acid receptor beta2 in breast carcinoma.
abstract: Hypermethylation of the retinoic acid receptor (RAR) beta2 has been detected in breast cancer cell lines and is known to repress the level of RAR beta2 transcription. RAR beta2 mRNA loss has often been detected in breast cancer tumors, whether promoter region methylation of the RAR beta2 gene accounts for its loss is still unknown. We examined the methylation status of RAR beta2 in breast tumors; 21 out of 50 (42%) breast tumors showed RAR beta2 hypermethylation. RT-PCR analysis showed a complete loss of RAR beta2 mRNA expression in 15 out of 43 (35%) breast tumors. No correlation between the hypermethylation and RAR beta2 loss was found, suggesting that hypermethylation is not fully responsible for the loss of expression of the RAR beta2 gene during breast tumorigenesis.
authors.affiliation: Department of Surgery, Affiliated Kihoku Hospital, Wakayama Medical University School of Medicine, Wakayama City, Japan. yang-qf@mail.wakayama-med.ac.jp
authors.forename: Q
authors.initials: Q
authors.lastname: Yang
authors.forename: T
authors.initials: T
authors.lastname: Sakurai
authors.forename: G
authors.initials: G
authors.lastname: Yoshimura
authors.forename: I
authors.initials: I
authors.lastname: Mori
authors.forename: M
authors.initials: M
authors.lastname: Nakamura
authors.forename: Y
authors.initials: Y
authors.lastname: Nakamura
authors.forename: T
authors.initials: T
authors.lastname: Suzuma
authors.forename: T
authors.initials: T
authors.lastname: Tamaki
authors.forename: T
authors.initials: T
authors.lastname: Umemura
authors.forename: K
authors.initials: K
authors.lastname: Kakudo
mesh_terms: D000368:Aged; D001943:Breast Neoplasms / Q000235:genetics* / Q000378:metabolism*; D018270:Carcinoma, Ductal, Breast / Q000235:genetics / Q000378:metabolism; D019175:DNA Methylation; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008875:Middle Aged; D011401:Promoter Regions, Genetic; D012333:RNA, Messenger / Q000378:metabolism; D018168:Receptors, Retinoic Acid / Q000096:biosynthesis* / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D012333:RNA, Messenger; D018168:Receptors, Retinoic Acid; C082925:retinoic acid receptor beta