ANGI-05CORRELATION BETWEEN VEGF AND YKL-40 TISSUE EXPRESSION AND PLASMA LEVELS IN GLIOBLASTOMA

Abstract

The secreted glycoprotein YKL-40 is elevated (compared to normal) both in plasma and tumor tissue in several types of cancers including glioblastoma (GBM), which is a highly vascularized aggressive malignant brain tumor with a devastating prognosis and limited treatment options. YKL-40 regulates Vascular Endothelial Growth Factor (VEGF) and long-term inhibition of VEGF induces YKL-40, thereby making these pro-angiogenic factors important for the development of GBM vascular phenotype. When evaluated independently, both plasma and tumor tissue YKL-40 levels have proven prognostic in patients with GBM. However, no direct comparison of the two parameters has been reported yet. In search of reliable biomarkers in GBM, this study aimed at exploring the putative correlation between tumor/plasma YKL-40 and VEGF levels in matched primary GBM tissue biopsies and plasma samples and their impact on GBM patient survival. Biopsies and plasma samples from 50 patients with GBM were collected from 2005 to 2015 at Rigshospitalet, Copenhagen, Denmark in relation to neurosurgery, and analyzed for YKL-40 and VEGF by immunohistochemistry and commercial enzyme-linked immunosorbent assay. Clinical data including age, sex, steroid dose, performance status, progression-free survival, overall survival etc. have been compiled in a clinical database. Preliminary results evaluating the correlation between above-mentioned markers in plasma and tumor tissue and their impact on GBM patient survival will be presented. We sincerely hope that our data will provide some insights into the regulation of the GBM angiogenic phenotype and its contribution to poor prognosis in this fatal disease.