Biomarker potential of IL-6 and VEGF-A in ascitic fluid of epithelial ovarian cancer patients

Background: Ovarian cancer is represented with significantly higher mortality rate predominately due to asymptomatic behaviour during initial disease course and at diagnosis majority patients already progressed to advanced stage. Acellular fraction of ascites in epithelial ovarian cancer (EOC) has been suggested to promote growth of tumor cells by providing ambient micro-environment for their proliferation. This acellular fraction contains multiple growth factors including IL-6 and VEGF-A, which were exploited to establish their bio-marker significance in EOC patients. Methods: IL-6 and VEGF-A levels in ascitic fluid of 30 EOC patients and 15 controls were measured using high sensitivity sandwich enzyme linked immune sorbent (ELISA) assay. Their levels were correlated with clinicopathological characteristics and bio-marker potential was assessed. Results and conclusion: EOC patients showed significantly higher levels for IL-6 (median-5636 pg/ml) and VEGF-A (median-4556 pg/ml) in ascitic fluid compared to controls. Levels of IL-6 and VEGF-A significantly correlated with clinico-pathological parameters. ROC curves of IL-6 and VEGF-A showed absolute combination of sensitivity and specificity. Kaplan Meier analysis demonstrated that higher levels of IL-6 and VEGF-A were significantly associated with shorter progression free survival. Thus, this study revealed that IL-6 and VEGF-A have great potential to be used as superior bio-markers for progression free survival in future after validation in larger patients' cohort.