Expression profi les of PIK3CA, RUNX3, COX-2 and DMBT1 genes in brain tumor prognosis: a preliminary study

The two main subgroups of the important genes functioning in the development of cancer including brain tumors are tumor suppressor genes and oncogenes. the aim of this pilot study was to determine the expression profiles of tumor suppressor genes; runx3 (runt-related transcription factor 3), dmbt1 (deleted in malignant brain tumors 1), and oncogenes pik3ca (phosphoinositide-3-kinase, catalytic, alpha polypeptide) and cox–2 (cyclooxygenase-2) in brain tumors. explant cell cultures were performed using brain tumor tissues from the 14 cases. total rna was isolated from the cultured cells. relative ratio of expression profiles of the tumor suppressor genes and oncogenes were determined by using real-time online rt-pcr. u-87mg cell line was used as positive control. the mean relative ratios of dmbt1, runx3, cox-2 and pik3ca genes were found; 72.2, 59.3, 0.119 and 48.5; respectively. cox-2 over-expression correlated with a significantly reduced survival (log- rank, p= 0.049). suppression of dmbt1 and runx3 is associated with decreased survive, however no significant difference was determined between expressions of pik3ca, dmbt1 and runx3 genes and overall survival. high cox-2 expression is found to be associated with clinically more aggressive brain tumors. our preliminary data suggests that cox-2 gene may be used as a therapeutic target.