RT Journal Article
SR Electronic
T1 Bleomycin Induces Caveolin-1 and -2 Expression in Epithelial Lung Cancer A549 Cells
JF Anticancer Research
JO Anticancer Res
FD International Institute of Anticancer Research
SP 1343
OP 1351
VO 27
IS 3A
A1 LINGE, ANNETT
A1 MORISHIMA, NOBUHIRO
A1 KASPER, MICHAEL
A1 BARTH, KATHRIN
YR 2007
UL http://ar.iiarjournals.org/content/27/3A/1343.abstract
AB Background: Bleomycin induces apoptosis in alveolar epithelial cells. The expression of caveolin-1 and -2 in lung epithelial-derived A549 cells was analysed in terms of apoptosis after exposure to bleomycin. Materials and Methods: Apoptosis was investigated using flow cytometry, ELISA, immunohistochemistry and Western blot analysis. Caveolin-1 and -2 were determined at the protein level (Western blot). Intracellular caveolin-1 distribution was studied with immunofluorescence, as well as sucrose density gradient centrifugation. Results: Caveolin-1 and -2 were up-regulated 1 h after exposure to bleomycin and preceding the occurrence of caspase-8, and of caspase-3 and caspase-9 cleavage products. Sucrose density gradient centrifugation revealed that bleomycin exposure led to a partial translocation of caveolin-1 from caveolin-rich membrane fractions to non-raft fractions. Successful inhibition of bleomycin-induced apoptosis by the broad-spectrum caspase inhibitor zVAD-fmk did not influence the amount of caveolin-1 and -2. Conclusion: The early up-regulation of caveolin-1 and -2 following bleomycin exposure is a rather apoptosis-independent event related to other unknown mechanisms of bleomycin-mediated cell injury. Copyright© 2007 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved