title: [Effect of stable DNA methyltransferase 3bknockdown on proliferation and apoptosis in bladder cancer cells in vitro].
abstract: OBJECTIVE
  To investigate the effect of stable knockdown of DNA methyltransferase 3b (DNMT3b) on the proliferation and apoptosis of bladder cancer cells.
  
  
  METHODS
  Lentivirus expressing DNMT3b siRNA or the negative control siRNA was infected in human bladder cancer BIU-87 cells. MTT assay and flow cytometry were used to detect cell proliferation and apoptosis, respectively. The inhibitory effect of DNMT3b knockdown on xenograft tumors in nude mice was observed. Real-time PCR and Western blotting were carried out to investigate the expression level of cell apoptosis related genes. Methylation specific PCR was used to examine the methylation in the promoter region of the cell apoptosis related genes.
  
  
  RESULTS
  The results of real-time PCR and Western blotting showed that DNMT3b mRNA and protein level were stably knocked down in BIU-87 cells. Stable DNMT3b knockdown suppressed BIU-87 cell growth and the tumor formation ability of the cells in nude mice. DNMT3b knockdown promoted the apoptosis of BIU-87 cells, increased the mRNA and protein expression of the cell growth and apoptosis related genes including DAPK, Bax and RASSF1A, and significantly decreased the methylation of these genes.
  
  
  CONCLUSIONS
  Stable DNMT3b knockdown can affect the methylation of the cell growth and apoptosis related genes to regulate their expression, which might be a possible mechanism for suppressed cell growth and enhanced apoptosis of BIU-87 cells.
authors.affiliation: Department of Urology, Zhujiang Hospital, South Medical University, Guangzhou 510282, China.E-mail: franciske0827@163.com.
authors.forename: Ke
authors.initials: K
authors.lastname: Chen
authors.forename: Bing-Kun
authors.initials: BK
authors.lastname: Li
authors.forename: Kai
authors.initials: K
authors.lastname: Xu
authors.forename: Abai
authors.initials: A
authors.lastname: Xu
authors.forename: Chunxiao
authors.initials: C
authors.lastname: Liu
authors.forename: Shaobo
authors.initials: S
authors.lastname: Zheng
authors.forename: Yawen
authors.initials: Y
authors.lastname: Xu
authors.forename: Chenyao
authors.initials: C
authors.lastname: Jia
authors.forename: Qi
authors.initials: Q
authors.lastname: Liu
authors.forename: Hulin
authors.initials: H
authors.lastname: Li
mesh_terms: D000818:Animals; D017209:Apoptosis; D002453:Cell Cycle; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D004248:DNA (Cytosine-5-)-Methyltransferases / Q000235:genetics*; D055785:Gene Knockdown Techniques; D006801:Humans; D051379:Mice; D008819:Mice, Nude; D009368:Neoplasm Transplantation; D034741:RNA, Small Interfering; D060888:Real-Time Polymerase Chain Reaction; D001749:Urinary Bladder Neoplasms / Q000235:genetics / Q000473:pathology*; D000097584:DNA Methyltransferase 3B
chemical_list: D004248:DNA (Cytosine-5-)-Methyltransferases; D034741:RNA, Small Interfering; D000097584:DNA Methyltransferase 3B
keywords: bladder cancer; DNMT3b.