title: The effects of PTBP3 silencing on the proliferation and differentiation of MKN45 human gastric cancer cells.
abstract: OBJECTIVE
  PTBP3 overexpression inhibits the differentiation of leukemia cells; however, its effects on the differentiation and proliferation of solid cancer cells remain unclear. Thus, the impact of PTBP3 on the differentiation and proliferation of gastric cancer cells was investigated.
  
  
  METHODS
  PTBP3 expression was analyzed in normal and tumor tissues using immunohistochemistry. A xenograft model was established in nude mice by subcutaneous injection of untransfected human gastric cancer MKN45 cells or those expressing a control vector or PTBP3 siRNA. We analyzed the tumor inhibition rate, the expression of PTBP3, the PCNA-positive rate and the serum levels of CEA, CA199, CA125, LDH, ALP and γ-GT in different groups.
  
  
  RESULTS
  The tumor weights in the PTBP3 siRNA group were significantly lower than that of the MKN45 cell control group (P<0.001). Immunohistochemistry analysis of PCNA expression revealed that it was markedly reduced after PTBP3 silencing. ELISAs showed that the serum levels of CEA and CA199 tumor markers as well as LDH and ALP were reduced after PTBP3 silencing. Transmission electron microscopy revealed that MKN45 cells expressing PTBP3 siRNA had reduced nuclear-to-cytoplasmic ratio and regular nuclei, suggesting differentiation.
  
  
  CONCLUSIONS
  PTBP3 may promote proliferation and inhibit the differentiation of human gastric cancer MKN45 cells.
authors.affiliation: Department of Oncology, Longhua Hospital, Shanghai University of Traditional Chinese Medicine, 725 South Wanping Road, Shanghai 200032, PR China.
authors.forename: Bin
authors.initials: B
authors.lastname: Chen
authors.affiliation: Department of Oncology, Longhua Hospital, Shanghai University of Traditional Chinese Medicine, 725 South Wanping Road, Shanghai 200032, PR China. Electronic address: aiguang@hotmail.com.
authors.forename: Ai-Guang
authors.initials: AG
authors.lastname: Zhao
authors.affiliation: State Key Laboratory of Bioreactor Engineering and Shanghai Key Laboratory of Chemical Biology, East China University of Science and Technology, Shanghai 200237, PR China; Department of Molecular and Cellular Pharmacology, East China University of Science and Technology, Shanghai 200237, PR China.
authors.forename: Jin
authors.initials: J
authors.lastname: Shao
authors.affiliation: Department of Oncology, Longhua Hospital, Shanghai University of Traditional Chinese Medicine, 725 South Wanping Road, Shanghai 200032, PR China.
authors.forename: Xiao-Yan
authors.initials: XY
authors.lastname: Mu
authors.affiliation: State Key Laboratory of Bioreactor Engineering and Shanghai Key Laboratory of Chemical Biology, East China University of Science and Technology, Shanghai 200237, PR China; Department of Molecular and Cellular Pharmacology, East China University of Science and Technology, Shanghai 200237, PR China.
authors.forename: Lin
authors.initials: L
authors.lastname: Jiang
authors.affiliation: State Key Laboratory of Bioreactor Engineering and Shanghai Key Laboratory of Chemical Biology, East China University of Science and Technology, Shanghai 200237, PR China; Department of Molecular and Cellular Pharmacology, East China University of Science and Technology, Shanghai 200237, PR China.
authors.forename: Jian-Wen
authors.initials: JW
authors.lastname: Liu
mesh_terms: D000818:Animals; D014408:Biomarkers, Tumor / Q000097:blood; D002454:Cell Differentiation / Q000235:genetics; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D004797:Enzyme-Linked Immunosorbent Assay; D015972:Gene Expression Regulation, Neoplastic; D020868:Gene Silencing; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D046529:Microscopy, Electron, Transmission; D038941:Polypyrimidine Tract-Binding Protein / Q000235:genetics*; D018809:Proliferating Cell Nuclear Antigen / Q000235:genetics; D034741:RNA, Small Interfering / Q000008:administration & dosage*; D013274:Stomach Neoplasms / Q000235:genetics* / Q000473:pathology; D023041:Xenograft Model Antitumor Assays
chemical_list: D014408:Biomarkers, Tumor; C118823:PTBP3 protein, human; D018809:Proliferating Cell Nuclear Antigen; D034741:RNA, Small Interfering; D038941:Polypyrimidine Tract-Binding Protein
keywords: Gastric cancer differentiation; PTBP3; Proliferation