Differences in the Expression Patterns of TGF beta Isoforms and Associated Genes in Astrocytic Brain Tumors

Genes associated with the TGF beta isoforms are involved in a number of different cancers, and their effect on the progression of brain tumors is also being discussed. Using an oligonucleotide microarray method, we assessed differences in expression patterns of genes in astrocytic brain tumor sections from 43 patients at different stages of disease. Quantitative mRNA assessment of the three TGF beta isoforms was also performed by real-time RT-qPCR. Oligonucleotide microarray data were analyzed using the PL-Grid Infrastructure. The microarray analysis showed a statistically significant (p < 0.05) increase in TGF beta 1 and TGF beta 2 expression in G3/G4 stage relative to G2, whereas real-time RT-qPCR validation confirmed this change only for the TGF beta 2 isoform (p < 0.05). The oligonucleotide microarray method allowed the identification of 16 differential genes associated with TGF beta isoforms. Analysis of the STRING database showed that the proteins encoded by the analyzed genes form a strong interaction network (p < 0.001), and a significant number of proteins are involved in carcinogenesis. Differences in expression patterns of transcripts associated with TGF beta isoforms confirm that they play a role in astrocytic brain tumor transformation. Quantitative assessment of TGF beta 2 mRNA may be a valuable method to complement the diagnostic process in the future.