Adenovirus vectors activate survival pathways in lung epithelial cells

• Published in: American journal of physiology. Lung cellular and molecular physiology Vol. 287; no. 2; pp. L393 - L401
• Main Authors: Flaherty, Dawn M, Hinde, Sara L, Monick, Martha M, Powers, Linda S, Bradford, Mary A, Yarovinsky, Timur, Hunninghake, Gary W
• Format: Journal Article
• Language: English
• Published: United States 01.08.2004
• Subjects: Adenocarcinoma, Bronchiolo-Alveolar; Adenoviridae - genetics; Adenovirus; Antineoplastic Agents - pharmacology; Apoptosis - drug effects; Apoptosis - physiology; Cell Line, Tumor; Cell Survival - physiology; Cytomegalovirus; Gene Expression Regulation, Viral; Genetic Vectors - physiology; Humans; Lung Neoplasms; Mitogen-Activated Protein Kinases - metabolism; Protein-Serine-Threonine Kinases - metabolism; Proto-Oncogene Proteins - metabolism; Proto-Oncogene Proteins c-akt; Respiratory Mucosa - cytology; Respiratory Mucosa - physiology; Respiratory syncytial virus; Transcription, Genetic; Tumor Necrosis Factor-alpha - pharmacology
• ISSN: 1040-0605; 1522-1504
• DOI: 10.1152/ajplung.00359.2003

Department of Internal Medicine, University of Iowa Roy J. and Lucille A. Carver College of Medicine; and Veterans Affairs Medical Center, Iowa City, Iowa 52242 Submitted 16 October 2003 ; accepted in final form 19 April 2004 Airway epithelial cells are often the sites of targeted adenovirus vector delivery. Activation of the host inflammatory response and modulation of signal transduction pathways by adenovirus vectors have been previously documented, including activation of MAP kinases and phosphatidylinositol 3-kinase (PI3-kinase). The effect of activation of these pathways by adenovirus vectors on cell survival has not been examined. Both the PI3-kinase/Akt and ERK/MAP kinase signaling pathways have been linked to cell survival. Akt has been found to play a role in cell survival and apoptosis through its downstream effects on apoptosis-related proteins. Constitutive activation of either PI3-kinase or Akt blocks apoptosis induced by c-Myc, UV radiation, transforming growth factor- , Fas, and respiratory syncytial virus infection. We examined the effect of adenovirus vector infection on activation of these prosurvival pathways and its downstream consequences. Airway epithelial cells were transduced with replication-deficient adenoviral vectors containing a nonspecific transgene, green fluorescent protein driven by the cytomegalovirus promoter, or an empty vector with no transgene. They were then exposed to the proapoptotic stimulus actinomycin D plus TNF- , and evidence of apoptosis was evaluated. Compared with the cells treated with actinomycin/TNF alone, the adenovirus vector-infected cells had a 50% reduction in apoptosis. When we examined induction of the prosurvival pathways, ERK and AKT, in the viral vector-infected cells, we found that there was significant activation of both Akt and ERK. extracellular signal-regulated kinase; phosphatidylinositol 3-kinase; Akt; apoptosis Address for reprint requests and other correspondence: D. M. Flaherty, Div. of Pulmonary, Critical Care, and Occupational Medicine, Univ. of Iowa Hospitals and Clinics, C-33 GH, Iowa City, Iowa 52242 (E-mail: flahertydm{at}mail.medicine.uiowa.edu )