title: Overexpression of Pim-1 in bladder cancer.
abstract: BACKGROUND
  Pim-1 is a serine-threonine kinase which promotes early transformation, cell proliferation and cell survival during tumorigenesis. Several studies have demonstrated that Pim-1 kinase play a role in different cancer types, however, the function of Pim-1 in bladder cancer is poorly understood.
  
  
  METHODS
  Expression and localization of Pim-1 in human normal and malignant bladder specimens were examined by Immunohistochemistry and Pim-1 staining score was compared with several clinicopathologic parameters. To further demonstrate the biological function of Pim-1 in bladder cancer, its expression was validated in five bladder cancer cell lines by western blot and immunohistochemistry analyses. Subsequent knockdown of Pim-1 was achieved by lentivirus encoding small interfering RNA, and the effect of Pim-1 on bladder cell survival and drug sensitivity were further assessed by colony formation and cell proliferation assays.
  
  
  RESULTS
  When compared with normal epithelium, Pim-1 was overexpressed in bladder cancer epithelium, and the expression level was higher in invasive bladder cancer than Non-invasive bladder cancer specimens. Pim-1 was also detected in all the bladder cancer cell lines examined in our study. Moreover, the knockdown of Pim-1 significantly inhibited bladder cancer cell growth and also sensitized cells to chemotherapeutic drugs in vitro.
  
  
  CONCLUSIONS
  Our results in this study suggest that Pim-1 may play a role in bladder cancer initiation and progression. Since Pim-1 is also involved in bladder cancer cell survival and drug resistance, Pim-1 is a potential candidate for targeted therapy in bladder cancer.
authors.affiliation: Department of Urology, the First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, 510080 China.
authors.forename: Shengjie
authors.initials: S
authors.lastname: Guo
authors.forename: Xiaopeng
authors.initials: X
authors.lastname: Mao
authors.forename: Junxing
authors.initials: J
authors.lastname: Chen
authors.forename: Bin
authors.initials: B
authors.lastname: Huang
authors.forename: Chu
authors.initials: C
authors.lastname: Jin
authors.forename: Zhenbo
authors.initials: Z
authors.lastname: Xu
authors.forename: Shaopeng
authors.initials: S
authors.lastname: Qiu
mesh_terms: D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000032:analysis*; D015153:Blotting, Western; D002295:Carcinoma, Transitional Cell / Q000378:metabolism* / Q000473:pathology; D018450:Disease Progression; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D051573:Proto-Oncogene Proteins c-pim-1 / Q000096:biosynthesis*; D001749:Urinary Bladder Neoplasms / Q000378:metabolism* / Q000473:pathology
chemical_list: D014408:Biomarkers, Tumor; D051573:Proto-Oncogene Proteins c-pim-1