Apoptosis-related gene expression in tumor tissue samples obtained from patients diagnosed with glioblastoma multiforme

Abstract

Tumors of the brain are very diverse in their biological behavior and are therefore considered a major issue in modern medicine. The heterogeneity of gliomas, their clinical presentation and their responses to treatment makes this type of tumor a challenging area of research. Glioblastoma multiforme (GBM) is the most common, and biologically the most aggressive, primary brain tumor in adults. The standard treatment for patients with newly diagnosed GBM consists of surgical resection, radiotherapy and chemotherapy. However, resistance to chemotherapy is a major obstacle to successful treatment. The aim of this study was to examine the changes occurring in the expression levels of apoptosis-associated genes in tumor tissue biopsy samples from 7 patients diagnosed with GBM and compare our results with a human astrocyte cell line (used as a reference) cultured under basic conditions. For molecular analysis, we used a commercial pre-designed microfluidic array to quantify the expression of 93 apoptosis-associated human genes. Significant changes in the expression levels of genes were observed in the tumor tissue samples obtained from patients with GBM. We determined significant changes in gene expression (n=32) in all apoptotic signaling pathways (BCl-2, TNF, Caspases, NF-κB, IAP and CARD), while the most pronounced deregulation (>5-fold) were observed in 46.9% events. The results of this study underline the importance of apoptosis in heterogenous tumor tissue. The identification of the apoptotic gene panel in tissue biopsies from patients with GBM may help improve the effectiveness of treatments for GBM in clinical practice and may broaden our understanding of brain tumor cell metabolism. Recognizing the changes in the expression of pro-apoptotic and anti-apoptotic genes may aid in the development of novel treatment strategies founded on a molecular basis.