title: Promoter hypermethylation of Ras-related GTPase gene RRAD inactivates a tumor suppressor function in nasopharyngeal carcinoma.
abstract: Nasopharyngeal carcinoma (NPC) is endemic in southern China. In a genome-wide screen for genes inactivated by promoter hypermethylation, we identified Ras-related associated with diabetes (RRAD). Expression of RRAD was down-regulated in 83.3% (30/36) of the biopsies from NPC patients. RRAD was aberrantly methylated in 74.3% (26/35) of primary tumors, but not in normal nasopharyngeal epithelium. Ectopic RRAD expression in NPC cell lines inhibited the cell growth, colony formation, and cell migration. These results indicate that RRAD might act as a functional tumor suppressor and its epigenetic inactivation may play an important role in NPC development.
authors.affiliation: Department of Environmental and Molecular Medicine, Mie University Graduate School of Medicine, Japan.
authors.forename: Yingxi
authors.initials: Y
authors.lastname: Mo
authors.forename: Kaoru
authors.initials: K
authors.lastname: Midorikawa
authors.forename: Zhe
authors.initials: Z
authors.lastname: Zhang
authors.forename: Xiaoying
authors.initials: X
authors.lastname: Zhou
authors.forename: Ning
authors.initials: N
authors.lastname: Ma
authors.forename: Guangwu
authors.initials: G
authors.lastname: Huang
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Hiraku
authors.forename: Shinji
authors.initials: S
authors.lastname: Oikawa
authors.forename: Mariko
authors.initials: M
authors.lastname: Murata
mesh_terms: D001483:Base Sequence; D001706:Biopsy; D045744:Cell Line, Tumor; D019175:DNA Methylation; D017931:DNA Primers; D016147:Genes, Tumor Suppressor; D006801:Humans; D009303:Nasopharyngeal Neoplasms / Q000235:genetics* / Q000473:pathology; D011401:Promoter Regions, Genetic; D034741:RNA, Small Interfering; D060888:Real-Time Polymerase Chain Reaction; D018631:ras Proteins / Q000235:genetics*
chemical_list: D017931:DNA Primers; D034741:RNA, Small Interfering; C084355:RRAD protein, human; D018631:ras Proteins