Up-regulation of ALG-2 in hepatomas and lung cancer tissue.
ALG-2 was isolated in a screen for proteins involved in programmed cell death and is the first Ca(2+)-binding protein found to be directly involved in apoptosis. We have generated polyclonal antibodies that are suitable for detecting ALG-2 using different immunological methods. Three commercial antibodies against ALG-2 did neither detect mouse recombinant ALG-2 nor endogenous ALG-2 in Jurkat cell lysates, whereas our own affinity-purified antibody recognized recombinant as well as endogenous ALG-2. The specificity of the antibody was shown by preabsorbtion experiments and on ALG-2-deficient cells using Western blot analysis and immunohistochemistry. Western blot analysis of 15 different adult mouse tissues demonstrated that ALG-2 is ubiquitously expressed. We found that ALG-2 was more than threefold overexpressed in rat liver hepatoma compared to normal rat liver using Western blot analysis, a result confirmed by immunohistochemical analysis. Staining of four different lung cancer tissue microarrays including specimens of 263 patients showed that ALG-2 is mainly localized to epithelial cells and significantly up-regulated in small-cell lung cancers and in non-small-cell lung cancers. Our results lead to the conclusion that ALG-2 beside its known proapoptotic functions may be a player in survival pathways.
la Cour
Jonas M
JM
Department of Molecular Cell Biology, University of Copenhagen, Copenhagen, and the Department of Pathology, University Hospital, Copenhagen, Denmark.
Mollerup
Jens
J
Winding
Pernille
P
Tarabykina
Svetlana
S
Sehested
Maxwell
M
Berchtold
Martin W
MW
D000818:Animals; D000906:Antibodies / Q000276:immunology / Q000378:metabolism; D017209:Apoptosis; D051017:Apoptosis Regulatory Proteins; D002135:Calcium-Binding Proteins / Q000378:metabolism*; D006528:Carcinoma, Hepatocellular / Q000378:metabolism* / Q000473:pathology; D006801:Humans; D007150:Immunohistochemistry; D008113:Liver Neoplasms / Q000378:metabolism* / Q000473:pathology; D008175:Lung Neoplasms / Q000378:metabolism* / Q000473:pathology; D051379:Mice; D020411:Oligonucleotide Array Sequence Analysis; D051381:Rats; D014018:Tissue Distribution; D014407:Tumor Cells, Cultured; D015854:Up-Regulation
D000906:Antibodies; D051017:Apoptosis Regulatory Proteins; D002135:Calcium-Binding Proteins; C097753:PDCD6 protein, human; C490815:Pdcd6 protein, mouse