Effects of combining Taxol and cyclooxygenase inhibitors on the angiogenesis and apoptosis in human ovarian cancer xenografts

The present study aimed to investigate the combined effects of Taxol and cyclooxygenase (COX) inhibitors on angiogenesis and cell apoptosis of SKOV-3 human ovarian carcinoma cell xenograft-bearing mice. The experiments were continued for 28 days. Animals were treated with 3 mg/kg SC-560 (a COX-1-selective inhibitor) alone, 100 mg/kg celecoxib (a COX-2-selective inhibitor) alone or SC-560/celecoxib by gavage twice a day, 20 mg/kg Taxol alone intraperitoneally once a week or in combination with SC-560 or celecoxib or SC-560/celecoxib/Taxol for three weeks. The mRNA levels of vascular endothelial growth factor (VEGF) was determined by reverse transcription-polymerase chain reaction (RT-PCR). The microvessel density (MVD) of ovarian carcinoma was determined by immunohistochemistry with anti-CD(34) as the label. The apoptotic index was detected by the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling (TUNEL) method. The MVD value and apoptotic index in the SC-560/Taxol group were notably inhibited compared with the Taxol group (P<0.001). Moreover, the VEGF mRNA levels, MVD value and apoptotic index in the SC-560/Taxol group were significantly different from the celecoxib/Taxol group (P<0.05, P<0.05 and P<0.001, respectively). The present study demonstrated that SC-560 enhances the anti-angiogenic and pro-apoptotic effects of Taxol and these effects are better than with celecoxib.