Background: Glioblastomas are highly resistant to the standard therapy owing to their metabolic aggressiveness . These tumors are often marked by a radioresistant mutant, epidermal growth factor receptor variant III, EGFRvIII and its role in metabolic fueling has been implicated [2, 3]. In order to analyze their potential role in tumor progression, we aimed to evaluate the relationship between the expression levels of EGFRvIII and a brain glucose transporter (GLUT) and compared against the clinical grades of glioma.
Methods: Gliomas (n = 40) were analyzed by reverse transcriptase-polymerase chain reaction (RT-PCR) and sequencing methods for EGFRvIII detection. The EGFRvIII positive gliomas were analyzed for the gene expression levels of EGFRvIII and GLUT using real-time PCR assay and compared against the clinical grades using standard statistical tools. The protein level expressions of EGFR, EGFRvIII and GLUT were evaluated using immunohistochemistry in formalin fixed paraffin embedded (FFPE) sections of patient tumors.
Results: EGFRvIII was detected in 53% of the gliomas analyzed (Figure 1). Both EGFRvIII (p < 0.05) and GLUT (p < 0.05) showed significant upregulation in gene expressions among glioma patients. Interestingly, EGFRvIII showed strong positive correlation with GLUT (r = 0.865; p < 0.01). Most importantly, the levels of EGFRvIII (r = 0.838; p < 0.01) and GLUT (r = 0.771; p < 0.01) depicted significant positive correlation with the clinical grades of glioma. And the protein expressions of EGFR/EGFRvIII and GLUT were observed as regions of intense brown staining of FFPE sections of patient tumors by immunohistochemical evaluation.
S. Xavier, S Ramaiyer, K., Panikar, D., Nair, S., Menon, K., and Dr. Lakshmi Sumitra, “62 Molecular Analysis of Epidermal Growth Factor Receptor Variant III and Glucose Transporter Expressions in Different Grades of Glioma: Potential biomarkers for Targeted Therapy”, Annals of Oncology, vol. 28, p. mdx511.028, 2017.