[Differential expression of mitochondrial proteins in hepatoma cells analyzed using two-dimensional electrophoresis].

Background & Objective: Mitochondria play a key role in cell apoptosis. Proteomic analysis of mitochondria will contribute to the discovery of tumorigenic mechanism, early detection of cancer, and findings of anticarcinogens. This study was to identify the differentially expressed mitochondrial proteins in hepatoma cells using two-dimensional gel electrophoresis (2-DE).

Methods: Mitochondria were isolated from normal hepatocytes L02, and hepatoma QGY-7703 cells before and after treatment of epirubicin by density gradient centrifugation; the proteins of mitochondrial samples were analyzed with 2-DE.

Results: After density gradient centrifugation, the mitochondrial marker enzyme activities were increased by 11.8, 13.8, and 10.2 times, respectively, for L02 cells, untreated QGY-7703 cells, and epirubicin-treated QGY-7703 cells, and the 2-DE profiles identified 206, 217, and 214 protein spots, respectively, from the 3 samples. Compared L02 cells and QGY-7703 cells, 49 differentially expressed protein spots were identified; compared QGY-7703 cells before and after treatment of epirubicin, 29 differentially expressed protein spots were identified.

Conclusion: A set of differentially expressed protein spots are detected in mitochondria of QGY-7703 cells with density gradient centrifugation and 2-DE.