title: DNA methyltransferase 1 mediated aberrant methylation and silencing of SHP-1 gene in chronic myelogenous leukemia cells.
abstract: Extensive studies on SHP-1 protein and SHP-1 mRNA revealed that the diminishment or abolishment of the expression of SHP-1 in leukemias/lymphomas was due to aberrant promoter methylation. Thus far, the mechanism of epigenetic silencing of the SHP-1 tyrosine phosphatase gene that occurs in chronic myelogenous leukemia cells remains poorly understood.
  
  
  
  The expressions of the target molecules were determined by quantitative real time PCR and western blot, respectively. Bisulfite sequencing PCR was used to detect methylation status of DNA CpG. The lentiviral vectors were applied to modify gene expression.
  
  
  
  In the present study, we found that the promoter 2 of SHP-1 gene is located between positions from -577bp to +300bp, and 22 CpG sites contained in positions -353bp∼+182bp are aberrantly methylated in K562 cells. In vitro, we demonstrated that DNMT1 silencing induced demethylation of the 22 CpG sites located in the SHP-1 promoter and re-expression of SHP-1 gene in K562 cells. Moreover, we proved that the expression levels of DNMT1 and SHP-1 mRNA and protein were negatively correlated in K562 cells and BM aspirates mononuclear cells from CML patients.
  
  
  
  Collectively, these results indicate that DNMT1 mediates aberrant methylation and silencing of SHP-1 gene in chronic myelogenous leukemia cells, and provide a novel therapeutic target for CML.
authors.affiliation: Department of Hematology, Harrison International Peace Hospital, Hengshui, Hebei Province, 053000, PR China. Electronic address: yinghuali71@163.com.
authors.forename: Yinghua
authors.initials: Y
authors.lastname: Li
authors.affiliation: Hengshui Blood Center, Hengshui, Hebei Province, 053000, PR China.
authors.forename: Xuedong
authors.initials: X
authors.lastname: Liu
authors.affiliation: Department of Hematology, Harrison International Peace Hospital, Hengshui, Hebei Province, 053000, PR China.
authors.forename: Xiufeng
authors.initials: X
authors.lastname: Guo
authors.affiliation: Department of Hematology, Harrison International Peace Hospital, Hengshui, Hebei Province, 053000, PR China.
authors.forename: Xiao
authors.initials: X
authors.lastname: Liu
authors.affiliation: Department of Hematology, The Second Hospital of Hebei Medical University, Shijiazhuang, Hebei Province, 050000, PR China.
authors.forename: Jianmin
authors.initials: J
authors.lastname: Luo
mesh_terms: D000328:Adult; D000368:Aged; D015153:Blotting, Western; D000076123:DNA (Cytosine-5-)-Methyltransferase 1; D004248:DNA (Cytosine-5-)-Methyltransferases / Q000235:genetics*; D019175:DNA Methylation / Q000235:genetics; D005260:Female; D015973:Gene Expression Regulation, Leukemic / Q000235:genetics*; D020868:Gene Silencing; D006801:Humans; D020014:K562 Cells; D015464:Leukemia, Myelogenous, Chronic, BCR-ABL Positive / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D011401:Promoter Regions, Genetic / Q000235:genetics; D053824:Protein Tyrosine Phosphatase, Non-Receptor Type 6 / Q000235:genetics*; D060888:Real-Time Polymerase Chain Reaction; D055815:Young Adult
chemical_list: D000076123:DNA (Cytosine-5-)-Methyltransferase 1; D004248:DNA (Cytosine-5-)-Methyltransferases; C000619380:DNMT1 protein, human; C509249:PTPN6 protein, human; D053824:Protein Tyrosine Phosphatase, Non-Receptor Type 6
keywords: DNMT1; Gene silencing; Methylation; SHP-1