BACKGROUND: Potential tissue and serum biomarkers were assessed for predicting efficacy of bevacizumab in ovarian cancer (OC). PATIENTS AND METHODS: Twenty patients with OC received chemotherapy alone (control group) or in combination with bevacizumab (study group) in this non-randomised study. Pre- and post-treatment serum concentrations of vascular endothelial growth factor (VEGF), 8-hydroxydeoxyguanosine (8-OHdG) and tissue inhibitor of metalloproteinase-1 (TIMP-1) were measured in all patients. In addition, immunohistochemical expressions VEGF receptors (R1, R2), hypoxia-inducible factor 1alpha (HIF-1 alpha), matrix metalloproteinases (-2, -9) and TIMP-2 were analysed in tumours from bevacizumab-treated patients. RESULTS: 8-OHdG and HIF-1alpha immunostainings were more highly expressed among patients with progression-free survival (PFS) >23 months than in patients with PFS