title: MiR-29c regulates the expression of miR-34c and miR-449a by targeting DNA methyltransferase 3a and 3b in nasopharyngeal carcinoma.
abstract: BACKGROUND
  Nasopharyngeal carcinoma (NPC) is prevalent in South East Asia and Southern China particularly, despite the reported 5-year survival ratio is relative higher than other deadly cancers such as liver, renal, pancreas cancer, the lethality is characterized by high metastatic potential in the early stage and high recurrence rate after radiation treatment. MicroRNA-29c was found to be down-regulated in the serum as well as in the tissue of nasopharyngeal carcinoma tissue.
  
  
  METHODS
  In this study, we found accidentally that the transfection of pre-miR-29c or miR-29c mimics significantly increases the expression level of miR-34c and miR-449a but doesn't affect that of miR-222 using real-time quantitative PCR in nasopharyngeal carcinoma cell lines. To explore the molecular mechanism of the regulatory role, the cells are treated with 5-Aza-2-deoxycytidine (5-Aza-CdR) treatment and the level of miR-34c and miR-449a but not miR-222 accumulated by the treatment. DNA methyltransferase 3a, 3b were down-regulated by the 5-Aza-CdR treatment with western blot and real-time quantitative PCR.
  
  
  RESULTS
  We found that pre-miR-29c or miR-29c mimics significantly increases the expression level of miR-34c and miR-449a. We further found DNA methyltransferase 3a and 3b are the target gene of miR-29c. Restoration of miR-29c in NPC cells down-regulated DNA methyltransferase 3a, 3b, but not DNA methyltransferase T1.
  
  
  CONCLUSIONS
  The regulation of miR-29c/DNMTs/miR-34c\449a is an important molecular axis of NPC development and targeting DNMTs or restoring of miR-29c might be a promising therapy strategy for the prevention of NPC.
authors.affiliation: Hunan Provincial Tumor Hospital and the Affiliated Tumor Hospital of Xiangya School of Medicine, Central South University, Changsha, 410013, China.|Cancer Research Institute, School of Basic Medical Science, Central South University, Changsha, 410078, China.
authors.forename: Man
authors.initials: M
authors.lastname: Niu
authors.affiliation: Cancer Research Institute, School of Basic Medical Science, Central South University, Changsha, 410078, China.
authors.forename: Dan
authors.initials: D
authors.lastname: Gao
authors.affiliation: Department of Pathology, Second Xiangya Hospital, Central South University, Changsha, 410011, China.
authors.forename: Qiuyuan
authors.initials: Q
authors.lastname: Wen
authors.affiliation: Cancer Research Institute, School of Basic Medical Science, Central South University, Changsha, 410078, China.
authors.forename: Pingpin
authors.initials: P
authors.lastname: Wei
authors.affiliation: Cancer Research Institute, School of Basic Medical Science, Central South University, Changsha, 410078, China.|Guandong Provincial Yuebei People's Hospital, Shaoguan, 512025, China.
authors.forename: Suming
authors.initials: S
authors.lastname: Pan
authors.affiliation: Orthopedic Biomedical Materials Institute, Central South University, Changsha, 410083, China.
authors.forename: Cijun
authors.initials: C
authors.lastname: Shuai
authors.affiliation: Cancer Research Institute, School of Basic Medical Science, Central South University, Changsha, 410078, China.
authors.forename: Huiling
authors.initials: H
authors.lastname: Ma
authors.affiliation: Hunan Provincial Tumor Hospital and the Affiliated Tumor Hospital of Xiangya School of Medicine, Central South University, Changsha, 410013, China.|Cancer Research Institute, School of Basic Medical Science, Central South University, Changsha, 410078, China.
authors.forename: Juanjuan
authors.initials: J
authors.lastname: Xiang
authors.affiliation: Hunan Provincial Tumor Hospital and the Affiliated Tumor Hospital of Xiangya School of Medicine, Central South University, Changsha, 410013, China.|Cancer Research Institute, School of Basic Medical Science, Central South University, Changsha, 410078, China.
authors.forename: Zheng
authors.initials: Z
authors.lastname: Li
authors.affiliation: Department of Pathology, Second Xiangya Hospital, Central South University, Changsha, 410011, China.
authors.forename: Songqing
authors.initials: S
authors.lastname: Fan
authors.affiliation: Hunan Provincial Tumor Hospital and the Affiliated Tumor Hospital of Xiangya School of Medicine, Central South University, Changsha, 410013, China.|Cancer Research Institute, School of Basic Medical Science, Central South University, Changsha, 410078, China.
authors.forename: Guiyuan
authors.initials: G
authors.lastname: Li
authors.affiliation: Hunan Provincial Tumor Hospital and the Affiliated Tumor Hospital of Xiangya School of Medicine, Central South University, Changsha, 410013, China. shuping@csu.edu.cn.|Cancer Research Institute, School of Basic Medical Science, Central South University, Changsha, 410078, China. shuping@csu.edu.cn.
authors.forename: Shuping
authors.initials: S
authors.lastname: Peng
mesh_terms: D017209:Apoptosis / Q000235:genetics; D002277:Carcinoma; D045744:Cell Line, Tumor; D002681:China; D004248:DNA (Cytosine-5-)-Methyltransferases / Q000235:genetics*; D000090205:DNA Methyltransferase 3A; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D035683:MicroRNAs / Q000096:biosynthesis* / Q000235:genetics; D000077274:Nasopharyngeal Carcinoma; D009303:Nasopharyngeal Neoplasms / Q000235:genetics* / Q000473:pathology; D000097584:DNA Methyltransferase 3B
chemical_list: D004248:DNA (Cytosine-5-)-Methyltransferases; D000090205:DNA Methyltransferase 3A; D035683:MicroRNAs; D000097584:DNA Methyltransferase 3B; C000717967:DNMT3A protein, human; C532045:MIRN29a microRNA, human; C522425:MIRN34 microRNA, human; C544530:MIRN449 microRNA, human
keywords: DNA methyltransferase; Nasopharyngeal carcinoma; miR-29c; miR-34c; miR-449a