title: MiR-214 regulates oral cancer KB cell apoptosis through targeting RASSF5.
abstract: Ras association domain family member 5 (RASSF5), a member of the Ras association domain family, induces cell apoptosis by phosphorylating FOXO3a, which triggers target gene BIM (pro-apoptotic factor) activation. MiR-214 is overexpressed in oral cancer tissue, indicating its possible involvement in oral cancer pathogenesis. Bioinformatics analysis has revealed a complimentary sequence between miR-214 and the 3'-UTR of RASSF5 mRNA. However, whether miR-124 regulates RASSF5 in oral cancer remains poorly understood. We aimed to investigate the role of miR-214 in RASSF5 expression regulation in oral cancer. Tumor and paracarcinoma tissues were obtained from 48 oral cancer patients to examine miR-214 and RASSF5 expression. The relationship between miR-214 and RASSF5 was investigated by dual luciferase reporter gene assay. Oral cancer KB cells were cultured in vitro and divided into inhibitor NC, miR-214 inhibitor, Scramble-pMD18, RASSF5-pMD18, and miR-214 inhibitor + RASSF5-pMD18 groups. Caspase 3 activity, cell apoptosis, and total protein expression were measured by spectrophotometry, flow cytometry, and western blot, respectively. MiR-214 expression was significantly increased, while that of RASSF5 decreased in oral cancer tumor tissues compared to paracarcinoma tissues. Luciferase assay showed that miR-214 suppressed RASSF5 expression by targeting its 3'-UTR. Down-regulation of miR-214 and/or enhancement of RASSF5 expression markedly increased FOXO3a phosphorylation, BIM expression, caspase 3 activity, and apoptosis. In conclusion, miR-214 expression was elevated and RASSF5 was down-regulated in oral cancer. Moreover, miR-214 regulated KB cell apoptosis through targeted inhibition of RASSF5 expression, FOXO3a phosphorylation, and BIM expression, suggesting its possible application as a novel therapeutic oral cancer target.
authors.affiliation: Department of Stomatology, The Fourth Hospital of Hebei Medical University, Shijiazhuang, Hebei, China.
authors.forename: T K
authors.initials: TK
authors.lastname: Li
authors.affiliation: Department of Stomatology, Xingtai People's Hospital of Hebei Medical University, Xingtai, Hebei, China.
authors.forename: K
authors.initials: K
authors.lastname: Yin
authors.affiliation: Department of Stomatology, The Fourth Hospital of Hebei Medical University, Shijiazhuang, Hebei, China.
authors.forename: Z
authors.initials: Z
authors.lastname: Chen
authors.affiliation: Department of Stomatology, The Fourth Hospital of Hebei Medical University, Shijiazhuang, Hebei, China.
authors.forename: Y
authors.initials: Y
authors.lastname: Bao
authors.affiliation: Department of Stomatology, The Fourth Hospital of Hebei Medical University, Shijiazhuang, Hebei, China suxinzhangzxc@163.com.
authors.forename: S X
authors.initials: SX
authors.lastname: Zhang
mesh_terms: D048868:Adaptor Proteins, Signal Transducing; D000328:Adult; D000368:Aged; D017209:Apoptosis / Q000235:genetics*; D051017:Apoptosis Regulatory Proteins / Q000235:genetics; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000235:genetics; D015536:Down-Regulation; D005260:Female; D016147:Genes, Tumor Suppressor; D006801:Humans; D007624:KB Cells; D008297:Male; D035683:MicroRNAs / Q000235:genetics* / Q000378:metabolism; D008875:Middle Aged; D020559:Monomeric GTP-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D009062:Mouth Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D012333:RNA, Messenger / Q000235:genetics
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D051017:Apoptosis Regulatory Proteins; C547397:MIRN214 microRNA, human; D035683:MicroRNAs; C454042:RASSF5 protein, human; D012333:RNA, Messenger; D020559:Monomeric GTP-Binding Proteins