title: Aberrant DNA methyltransferase 1 expression in clear cell renal cell carcinoma development and progression.
abstract: OBJECTIVE
  To better understand the contribution of dysregulated DNA methyltransferase 1 (DNMT1) expression to the progression and biology of clear cell renal cell carcinoma (ccRCC).
  
  
  METHODS
  We examined the differences in the expression of DNMT1 in 89 ccRCC and 22 normal tissue samples by immunohistochemistry. In addition, changes in cell viability, apoptosis, colony formation and invading ability of ccRCC cell lines (786-0 and Caki-1) were assessed after transfection with DNMT1 siRNA.
  
  
  RESULTS
  We found DNMT1 protein was significantly higher expressed in ccRCC than that of in no-tumor tissues (56.2% and 27.3%, respectively, P=0.018). The expression of DNMT1 was strongly associated with ccRCC tumor size, tumor pathology stage, histological grading, lymph node metastasis, vascular invasion, recurrence and prognosis. Moreover, knockdown of DNMT1 expression significantly inhibited ccRCC cell viability, induced apoptosis, decreased colony formation and invading ability.
  
  
  CONCLUSIONS
  Expression of DNMT1 protein is increased in ccRCC tissues, and DNMT1 expression is associated with poor prognosis of patients. Experiments in vitro further showed DNMT1 played an essential role in proliferation and invasion of renal cancer cells. Moreover, targeting this enzyme could be a promising strategy for treating ccRCC, as evidenced by inhibited cell viability, increased apoptosis, decreased colony formation and invading ability.
authors.affiliation: 1 Department of Urology, Shengjing Hospital of China Medical University, Shenyang 110004, China ; 2 Department of Cell Biology, Harvard Medical School, Boston, MA, 02115, USA ; 3 Department of Nuclear Medicine, The First Affiliated Hospital of China Medical University, Shenyang 110001, China.
authors.forename: Ming
authors.initials: M
authors.lastname: Li
authors.affiliation: 1 Department of Urology, Shengjing Hospital of China Medical University, Shenyang 110004, China ; 2 Department of Cell Biology, Harvard Medical School, Boston, MA, 02115, USA ; 3 Department of Nuclear Medicine, The First Affiliated Hospital of China Medical University, Shenyang 110001, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Wang
authors.affiliation: 1 Department of Urology, Shengjing Hospital of China Medical University, Shenyang 110004, China ; 2 Department of Cell Biology, Harvard Medical School, Boston, MA, 02115, USA ; 3 Department of Nuclear Medicine, The First Affiliated Hospital of China Medical University, Shenyang 110001, China.
authors.forename: Yongsheng
authors.initials: Y
authors.lastname: Song
authors.affiliation: 1 Department of Urology, Shengjing Hospital of China Medical University, Shenyang 110004, China ; 2 Department of Cell Biology, Harvard Medical School, Boston, MA, 02115, USA ; 3 Department of Nuclear Medicine, The First Affiliated Hospital of China Medical University, Shenyang 110001, China.
authors.forename: Renge
authors.initials: R
authors.lastname: Bu
authors.affiliation: 1 Department of Urology, Shengjing Hospital of China Medical University, Shenyang 110004, China ; 2 Department of Cell Biology, Harvard Medical School, Boston, MA, 02115, USA ; 3 Department of Nuclear Medicine, The First Affiliated Hospital of China Medical University, Shenyang 110001, China.
authors.forename: Bo
authors.initials: B
authors.lastname: Yin
authors.affiliation: 1 Department of Urology, Shengjing Hospital of China Medical University, Shenyang 110004, China ; 2 Department of Cell Biology, Harvard Medical School, Boston, MA, 02115, USA ; 3 Department of Nuclear Medicine, The First Affiliated Hospital of China Medical University, Shenyang 110001, China.
authors.forename: Xiang
authors.initials: X
authors.lastname: Fei
authors.affiliation: 1 Department of Urology, Shengjing Hospital of China Medical University, Shenyang 110004, China ; 2 Department of Cell Biology, Harvard Medical School, Boston, MA, 02115, USA ; 3 Department of Nuclear Medicine, The First Affiliated Hospital of China Medical University, Shenyang 110001, China.
authors.forename: Qizhen
authors.initials: Q
authors.lastname: Guo
authors.affiliation: 1 Department of Urology, Shengjing Hospital of China Medical University, Shenyang 110004, China ; 2 Department of Cell Biology, Harvard Medical School, Boston, MA, 02115, USA ; 3 Department of Nuclear Medicine, The First Affiliated Hospital of China Medical University, Shenyang 110001, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Wu
keywords: Clear cell renal cell carcinoma (ccRCC); DNA methyltransferase 1 (DNMT1); immunohistochemistry; siRNA