title: Effects of lentivirus mediated STAT3 silencing on human chronic myeloid leukemia cells and leukemia mice.
abstract: OBJECTIVE
  To investigate the effects of lentivirus mediated STAT3 silencing on human chronic myeloid leukemia cells (K562) and the growth of chronic myeloid leukemia mice as well as to explore the potential mechanisms.
  
  
  METHODS
  Unbtreated K562 cells (CON), blank lentivirus transfected K562 cells (NC) and K562 cells expressing STAT3 siRNA (STAT3 siRNA) were injected into SCID mice to establish the chronic myeloid leukemia model in mice. The growth, peripheral white blood cell count and spleen index in these mice were determined.
  
  
  RESULTS
  In vitro experiment showed, when compared with control group, the interference efficiency of STAT3 expression was as high as 97.5% in K562 cells. Western blot assay revealed that the expression of c-Myc, Bcl-xL and Cyclin D1 reduced by 17.01%, 7.3% and 6.82%, respectively, showing significant difference when compared with control group (P < 0.01). These findings were consistent with those from fluorescence quantitative PCR. In vivo experiment showed the body weight of mice reduced progressively and the peripheral white blood cell count increased gradually in control group, accompanied by dragging hind limbs and progressive enlargement of the spleen. The body weight remained unchanged, peripheral white blood cell count reduced gradually and the spleen did not enlarge in mice treated with STAT3 siRNA expressing cells.
  
  
  CONCLUSIONS
  Lentivirus mediated STAT3 silencing may inhibit the expression of its downstream genes (c-Myc, Bcl-xL and Cyclin D1) related to cell proliferation, apoptosis and cycle to suppress the malignant biological behaviors, and STAT3 silencing also inhibit the leukemogenic potency of K562 cells in mice.
authors.affiliation: Department of Hematology, East Hospital, Tongji University School of Medicine Shanghai 200120, China.
authors.forename: Xinyan
authors.initials: X
authors.lastname: Jia
authors.affiliation: Department of Hematology, East Hospital, Tongji University School of Medicine Shanghai 200120, China.
authors.forename: Wenzhong
authors.initials: W
authors.lastname: Yang
authors.affiliation: Department of Hematology, Shanghai Xuhui Central Hospital & Shanghai Clinical Center, Chinese Academy of Sciences Shanghai 200031, China.
authors.forename: Jia
authors.initials: J
authors.lastname: Han
authors.affiliation: Department of Hematology, Shanghai Xuhui Central Hospital & Shanghai Clinical Center, Chinese Academy of Sciences Shanghai 200031, China.
authors.forename: Hong
authors.initials: H
authors.lastname: Xiong
keywords: Chronic myeloid leukemia; STAT3 siRNA; animal model; lentivirus