HIF-1α and VEGF Expression in Adult-type Diffuse High-Grade Astrocytoma

Abstract

Background: Gliomas stand as the prevalent primary malignant brain tumors in adults with astrocytoma being more common than oligodendroglioma. Based on isocitrate dehydrogenase (IDH) status, astrocytomas are classified as astrocytoma with mutated IDH and astrocytoma with wild-type IDH (glioblastoma). Tumor growth relies on angiogenesis, a process facilitated by key factors such as Vascular Endothelial Growth Factor (VEGF) and Hypoxia Inducible Factor-1α (HIF-1α). This study aims to investigate the VEGF and HIF-1α expression profiles in grade 4 astrocytomas, encompassing both mutated IDH and wild-type IDH. Method: This study was conducted on 43 formalin fixed paraffin embedded (FFPE) materials of surgical specimens from adult-type grade 4 astrocytoma. Immunohistochemistry with IDH1 R132H was carried out to determine the IDH status, followed by assessment of HIF-1α and VEGF expression using semi-quantitatively utilizing immunoreactive score (IRS), and categorized as negative, weak, moderate, and strong. Results: Statistical analysis revealed no disparity in HIF-1α expression between both tumor types, nor was there a difference in VEGF expression in both tumor types, yet a positive association was established between VEGF and HIF-1α expression levels in IDH mutant and wild type of grade 4 astrocytoma with moderate strength (r=0.433). Conclusion: HIF-1α and VEGF are positively linked, despite the IDH status, and simultaneously work to promote angiogenesis in diffuse high-grade astrocytoma