One explanation for these limitations is a learn more potential link between antiangiogenic therapy and increased metastasis [5]. In RIP-Tag2 mice treated with the VEGF receptor 2-inhibitor DC101, although tumors were smaller, they showed significantly more invasive and malignant phenotypes, with most showing wide fronts of invasion into urrounding acinar tissues [6]. Rodents treated with an anti-VEGF antibody showing a striking

increase in the number and total area of small satellite tumors compared with those that had not received antiangiogenic therapy, and tumor cells often had migrated over long distances [7, 8]. Together, these results suggest that antiangiogenic therapy may influence the progression of metastatic disease. To understand the reasons for these observations and to enable enduring benefits of antiangiogenic therapies, we examined the effect of a VEGF-neutralizing antibody on metastasis in mice after short-term administration. Furthermore, the hypoxic response and vasculogenic mimicry (VM) formation were assessed in this study. Materials Antibodies selleck chemical For western blotting and

histopathological analyses, a mouse anti-HIF-1α monoclonal antibody was purchased from Novus Biologicals (Littleton, CO, USA), CD34 monoclonal antibody from Abgent (San Diego, CA, USA). Cell lines The human ovarian cancer cell line SKOV3 was purchased from the ATCC and transfected with a luciferase-expressing lentivirus containing an independent open-reading frame of GFP. After 72 hours, cells were examined by fluorescence microscopy to confirm infection. Luciferase expression was determined using luciferin and an in vivo imaging system (Xenogen). Cells were maintained in RPMI-1640 medium supplemented with 10% heatinactivated fetal bovine serum (Gibco Invitrogen Corp), and incubated at 37°C in a humidified atmosphere containing 5% CO2. Three-dimensional(3D) PTK6 cultures Matrigel (BD Biosciences) was placed

dropwise onto glass coverslips in 12-well culture plates and allowed to polymerize for 30 min at 37°C. SKOV3 cells were then seeded onto the 3D matrix in complete medium. Animal models SKOV3LUC+ cells (1.2 × 106 cells) were directly injected into the tail vein of 6- 8-week-old female nude mice. Forty mice were assigned into four groups(A, B, C and D). Group A was treated with phosphate-buffered saline (PBS) bi-weekly for 3 weeks. Group B was treated with 40 mg/kg bevacizumab bi-weekly for 3 weeks. Group C was treated with 3 mg/kg cisplatin weekly for 3 weeks. Group D was treated with both bevacizumab bi-weekly and cisplatin weekly for 3 weeks. Bevacizumab and cisplatin were administered intraperitoneally. Body weight was measured and recorded weekly. Metastatic disease progression in SKOV3LUC+ tumor-bearing mice was monitored. Before mice were anesthetized with Forane, an aqueous QNZ solution of luciferin (150 mg/kg) was intraperitoneally injected at 10 min prior to imaging.