title: Expression of beclin 1 in bladder cancer and its clinical significance.
abstract: BACKGROUND
  The aim of this study is to explore the expression of beclin 1, an autophagy gene, in bladder cancer and to evaluate its clinical and prognostic significance in patients with bladder cancer.
  
  
  METHODS
  Beclin 1 expression was examined at mRNA and protein levels by real-time quantitative polymerase chain reaction (RT-PCR), Western blotting, and immunohistochemistry in bladder cancer tissues and adjacent normal bladder tissues. The relationship between the expression of beclin 1 and clinicopathological characteristics and prognosis was statistically analyzed.
  
  
  RESULTS
  mRNA level, protein expression and immunoreactivity of beclin 1 were decreased in bladder cancer tissues compared with adjacent normal tissues. Downregulation of beclin 1 was more frequent in tumors with higher histological grades (the expression of beclin 1 was reduced by 49.0% in G1 and G2, and by 71.8% in G3, p=0.010), and was also reduced by 69.5% in the muscle invasive type and by 51.1% in the non-muscle invasive type (p=0.04). Reduced beclin 1 expression was positively associated with higher histological grade and more advanced clinical stage (p<0.05). Kaplan-Meier survival analysis revealed that patients exhibiting lower beclin 1 expression experienced a shorter survival than those with higher expression (p=0.006). Cox proportional hazards regression analysis showed that beclin 1 protein is an independent predictor of survival (p=0.005).
  
  
  CONCLUSIONS
  Beclin 1 has an influence on the progression of bladder cancer and might serve as a potential prognostic factor for patients with bladder cancer.
authors.affiliation: Department of Oncology, the Second Affiliated Hospital of Guangzhou medical college, Guangzhou, China.
authors.forename: Gui-hong
authors.initials: GH
authors.lastname: Liu
authors.forename: Qian
authors.initials: Q
authors.lastname: Zhong
authors.forename: Yun-lin
authors.initials: YL
authors.lastname: Ye
authors.forename: Hong-bo
authors.initials: HB
authors.lastname: Wang
authors.forename: Li-juan
authors.initials: LJ
authors.lastname: Hu
authors.forename: Zi-ke
authors.initials: ZK
authors.lastname: Qin
authors.forename: Mu-sheng
authors.initials: MS
authors.lastname: Zeng
authors.forename: Bo-hang
authors.initials: BH
authors.lastname: Zeng
mesh_terms: D051017:Apoptosis Regulatory Proteins / Q000235:genetics / Q000378:metabolism*; D000071186:Beclin-1; D002295:Carcinoma, Transitional Cell / Q000378:metabolism* / Q000401:mortality / Q000473:pathology; D005260:Female; D015870:Gene Expression; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D008875:Middle Aged; D011379:Prognosis; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D012189:Retrospective Studies; D047368:Tumor Burden; D001749:Urinary Bladder Neoplasms / Q000378:metabolism* / Q000401:mortality / Q000473:pathology
chemical_list: D051017:Apoptosis Regulatory Proteins; C491997:BECN1 protein, human; D000071186:Beclin-1; D008565:Membrane Proteins; D012333:RNA, Messenger