Proteomics-based analysis of a pair of glioma cell lines with different tumor forming characteristics

Glioma is the most common malignant disease in the brain, and recurrence is the main cause of death from this disease. Tumor recurrence involves multiple steps, and requires the accumulation of the altered expression of many different proteins. Identification of the recurrence associated protein profile in glioma cell lines will be helpful in clarifying the molecular mechanisms underlying glioma recurrence. In this report, two glioma cell lines with distinct tumor forming ability in vitro and in vivo were chosen and the different protein expression patterns were analyzed by proteomics method. To confirm the utility of this method, we validated the differential expression of one protein, cathepsin D, by immunohistochemistry analysis. Forty-six proteins appeared differently between two cell lines and 18 of them were identified. These 18 are involved in cell proliferation, DNA replication, protein synthesis, invasion, angiogenesis and neurotrophic factor. All of these molecules are important in tumor growth, and a subset of them may be related to glioma recurrence. These findings may contribute to the discovery of new diagnostic markers and therapeutic targets of glioma.