Variant protein patterns in hepatomas and transformed liver cell lines as determined by high resolution two-dimensional gel electrophoresis (2DE).
Deviations in the pattern of soluble proteins from chemically induced primary rat hepatomas and from transformed, tumorigenic liver cell lines were determined by high resolution two-dimensional gel electrophoresis (2DE). As compared with the protein pattern of normal rat liver with approximately 1300 protein spots visible in silver-stained gels, quantitative and qualitative alterations were found in hepatomas including neoexpression of glutathione-S-transferase P, as described earlier. After correction for proliferation-related changes by comparison with gels of cells from regenerating rat liver, 30 protein variants remained, which were identically up- (n = 6) or down-regulated (n = 18) or were detected as new spots (n = 6) in primary hepatomas and transformed tumorigenic liver cell lines which are devoid of contaminating nonparenchymal cells. Seven of these variants showed a reduced expression in short-term cultured liver cells indicating dedifferentiation processes in the transformed state. Several hepatoma- and transformation-associated variants were found in clusters of similar mol. wt and/or pI, among them a complex of eight protein variants at approximately 33-35.5 kDa and a pI of approximately 6.6-7.4. Spots of this cluster show considerable changes between the investigated experimental groups and might be suited for being studied at the level of posttranslational modification during carcinogenesis.
Zeindl-Eberhart
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Institute of Pathology, University of Munich, Germany.
Rabes
H M
HM
D000818:Animals; D002460:Cell Line; D002471:Cell Transformation, Neoplastic; D002478:Cells, Cultured; D004052:Diethylnitrosamine; D015180:Electrophoresis, Gel, Two-Dimensional / Q000379:methods; D005982:Glutathione Transferase / Q000032:analysis; D006918:Hydroxyurea; D007525:Isoelectric Focusing / Q000379:methods; D007527:Isoenzymes / Q000032:analysis; D008099:Liver / Q000737:chemistry* / Q000502:physiology; D008114:Liver Neoplasms, Experimental / Q000139:chemically induced / Q000737:chemistry* / Q000201:enzymology; D008115:Liver Regeneration; D008297:Male; D008770:Methylnitrosourea; D009363:Neoplasm Proteins / Q000302:isolation & purification*; D011230:Precancerous Conditions / Q000139:chemically induced / Q000737:chemistry* / Q000201:enzymology; D011506:Proteins / Q000302:isolation & purification*; D051381:Rats; D011919:Rats, Inbred Strains
D007527:Isoenzymes; D009363:Neoplasm Proteins; D011506:Proteins; D004052:Diethylnitrosamine; D008770:Methylnitrosourea; D005982:Glutathione Transferase; D006918:Hydroxyurea