[Proteomic analysis of rat astrocytes and C6 glioma cells].

OBJECTIVE: To compare the protein profiles between glioma cells and normal astrocytes.

METHODS: Proteomic assay was performed on human C6 glioma cells and purified SD rat astrocytes. Two-dimensional gel electrophoresis (2-DE) and PDQuest software were applied for the comparison of protein image between the C6 cells and astrocytes. The differential protein spots were identified with Matrix-assisted laser desorption/ionization-time of flight-mass spectrometry (MALDI-TOF-MS) and further bioinformatic analysis. The differential expression of the interesting genes was confirmed by semi-quantitative RT-PCR.

RESULTS: Twenty-four differential protein spots were revealed by 2-DE assay. The peptide mass fingerprints (PMFs) of 17 proteins were obtained by MALDI-TOF-MS. Among them, six proteins were determined by further bioinformatic analysis. Compared with the expression level in astrocytes, the identified proteins showed higher expression level in the C6 glioma cells including phosphoglycerate mutase 1, glutathione S-transferase P (GST P), annexin A2 and calreticulin, while the proteins showed lower expression level included vimentin and gamma-actin. The results of RT-PCR confirmed the differential expressions of phosphoglycerate mutase 1, annexin A2 and vimentin identified by 2-DE assay.

CONCLUSION: The identified proteins differentially expressed in C6 cells and astrocytes are associated with many important cellular processes and functions such as anaerobic glycolysis, cytoskeleton organization, biotransformation, and signal transduction, and play important roles in tumor growth, migration, and anti-cancer drug resistance.