title: Adenovirus-mediated Bak gene transfer induces apoptosis in mesothelioma cell lines.
abstract: OBJECTIVE
  Conventional treatment for mesothelioma is largely ineffective. We therefore evaluated the novel approach of adenoviral gene transfer of the proapoptotic Bcl-2 family member Bak in mesothelioma cancer cell lines, which are sensitive and resistant to adenoviral p53.
  
  
  METHODS
  Binary adenoviral Bak (Ad/GT-Bak and Ad/GV16) and LacZ (Ad/GT-LacZ and Ad/GV16) vectors were used for transduction of the mesothelioma cell lines I-45 (p53 resistant) and REN (p53 sensitive). Protein levels were determined by Western blotting. Apoptosis was assessed by morphologic changes, caspase-3 cleavage, and fluorescence-activated cell sorter analysis of subdiploid populations. Cell viability was determined with the XTT assay. Statistical analysis was performed with analysis of variance and the Student t test.
  
  
  RESULTS
  High levels of Bak gene transfer were seen after coadministration of Ad/GT-Bak and Ad/GV16 in both mesothelioma cell lines. Apoptosis was induced 24 hours after Bak but not LacZ gene transfer ([Bak: I-45, 36%; REN, 25%] vs [LacZ: I-45, 1%; REN, 3%], P <.05]) in p53-sensitive (REN) and p53-resistant (I-45) cell lines. Cellular viability was significantly decreased 48 to 72 hours after Bak gene transfer compared with control vector in both cell lines (72 hours: Bak I-45, 1.4% +/- 1.0%, and Bak REN, 4.7% +/- 1%, vs Lac-Z I-45, 83% +/- 3%, and Lac-Z REN, 100% +/- 1%; P <.05).
  
  
  CONCLUSIONS
  Adenovirus-mediated overexpression of the Bak gene induces apoptosis and decreased cellular viability in p53-sensitive and p53-resistant mesothelioma cells. These data suggest that the gene transfer of proapoptotic Bcl-2 family members may represent a novel gene therapy strategy to treat mesothelioma.
authors.affiliation: Department of Thoracic and Cardiovascular Surgery, and the Department of Molecular Pathology, The University of Texas M.D. Anderson Cancer Center, Houston, Texas 77030, USA.
authors.forename: A
authors.initials: A
authors.lastname: Pataer
authors.forename: W R
authors.initials: WR
authors.lastname: Smythe
authors.forename: R
authors.initials: R
authors.lastname: Yu
authors.forename: B
authors.initials: B
authors.lastname: Fang
authors.forename: T
authors.initials: T
authors.lastname: McDonnell
authors.forename: J A
authors.initials: JA
authors.lastname: Roth
authors.forename: S G
authors.initials: SG
authors.lastname: Swisher
mesh_terms: D000256:Adenoviridae / Q000235:genetics*; D017209:Apoptosis / Q000235:genetics; D015153:Blotting, Western; D002470:Cell Survival; D005434:Flow Cytometry; D015870:Gene Expression; D005822:Genetic Vectors; D006801:Humans; D008565:Membrane Proteins / Q000235:genetics* / Q000378:metabolism; D008654:Mesothelioma / Q000235:genetics / Q000473:pathology* / Q000821:virology; D009154:Mutation; D010997:Pleural Neoplasms / Q000235:genetics / Q000473:pathology* / Q000821:virology; D014161:Transduction, Genetic / Q000379:methods*; D014407:Tumor Cells, Cultured; D016159:Tumor Suppressor Protein p53 / Q000235:genetics; D050998:bcl-2 Homologous Antagonist-Killer Protein
chemical_list: C494772:BAK1 protein, human; D008565:Membrane Proteins; D016159:Tumor Suppressor Protein p53; D050998:bcl-2 Homologous Antagonist-Killer Protein