Correlation of serum urokinase plasminogen activator (uPA) to progression of recurrent malignant glioma during bevacizumab treatment: A marker of invasive phenotype and a candidate to monitor therapy

2059 Background: Identification of circulating markers that predict tumor response or reflect progression is of crucial importance when using antiangiogenic agents. However, to date, no such parameters have been identified particularly for bevacizumab, for which, recently, increasing data have supported a role in patient with recurrent malignant glioma. Methods: Serial serum levels of VEGF, VEGFR2, FGF, SDFα, urokinase plasminogen activator (uPA), plasminogen activator inhibitor type I (PAI-1), and metalloprotesase type 9 (MMP9) were determined in a cohort of 32 patients treated with bevacizumab and irinotecan for recurrent malignant glioma. Samples were collected at the start of treatment and then at 4 weeks intervals until progression. Serum levels were measured using an enzyme-linked immunosorbent assay. Progression was defined by MacDonald's criteria, modified by integrating increase of infiltration as measured on MRI by Flair sequence. All subjects were followed for PFS and OS. Cox model analysis is ...