title: Expression, regulation and roles of miR-26a and MEG3 in tongue squamous cell carcinoma.
abstract: MicroRNA miR-26a and long noncoding RNA (lncRNA) MEG3 gene have been independently reported to be tumor suppressor genes in various cancers, but neither has been previously associated with tongue squamous cell carcinoma (TSCC). We report here that miR-26a and lncRNA MEG3 gene expression were both strongly reduced in TSCC compared with levels in matched nonmalignant tissues, and combined low expression levels of both miR-26a and MEG3 emerged as an independent prognostic factor for poor clinical outcome in TSCC patients. Assays in the human TSCC cell lines SCC-15 and CAL27 showed that miR-26a targets the DNA methyltransferase 3B transcript and that its inhibition may result in the upregulation of MEG3, providing a plausible link between the observed reduction of miR-26a and MEG3 in TSCC tissue. Furthermore, the overexpression of miR-26a or MEG3 in SCC-15 and CAL27 cells inhibited cell proliferation and cell cycle progression, and promoted cell apoptosis. Considering the poor prognostic outcomes associated with reduced miR-26a and MEG3, our findings imply that these factors likely play important antitumor effects in TSCC pathogenesis. Furthermore, they represent potential prognostic biomarkers for stratification of TSCC patients.
authors.affiliation: Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology, Beijing, China.
authors.forename: Ling-Fei
authors.initials: LF
authors.lastname: Jia
authors.forename: Su-Bi
authors.initials: SB
authors.lastname: Wei
authors.forename: Ye-Hua
authors.initials: YH
authors.lastname: Gan
authors.forename: Yong
authors.initials: Y
authors.lastname: Guo
authors.forename: Kai
authors.initials: K
authors.lastname: Gong
authors.forename: Keith
authors.initials: K
authors.lastname: Mitchelson
authors.forename: Jing
authors.initials: J
authors.lastname: Cheng
authors.forename: Guang-Yan
authors.initials: GY
authors.lastname: Yu
mesh_terms: D017209:Apoptosis; D015153:Blotting, Western; D002294:Carcinoma, Squamous Cell / Q000235:genetics* / Q000401:mortality / Q000473:pathology; D002453:Cell Cycle; D049109:Cell Proliferation; D002478:Cells, Cultured; D004248:DNA (Cytosine-5-)-Methyltransferases / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D019175:DNA Methylation; D005260:Female; D005500:Follow-Up Studies; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D015603:Keratinocytes / Q000166:cytology / Q000378:metabolism; D008297:Male; D035683:MicroRNAs / Q000235:genetics*; D008875:Middle Aged; D009367:Neoplasm Staging; D011379:Prognosis; D062085:RNA, Long Noncoding / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015996:Survival Rate; D014062:Tongue Neoplasms / Q000235:genetics* / Q000401:mortality / Q000473:pathology; D000097584:DNA Methyltransferase 3B
chemical_list: D004248:DNA (Cytosine-5-)-Methyltransferases; D035683:MicroRNAs; D062085:RNA, Long Noncoding; D012333:RNA, Messenger; D000097584:DNA Methyltransferase 3B; C498907:MEG3 non-coding RNA, human; C528163:MIRN26 microRNA, human
keywords: DNMT3B; MEG3; lncRNA; miR-26a; squamous cell carcinoma