Real-time quantitative PCR analysis of U87ΔEGFR intracranial mouse models treated with bevacizumab

The combination of bevacizumab with temozolomide and radiotherapy was shown to prolong progression-free survival in newly diagnosed glioblastoma patients, and this emphasizes the potential of bevacizumab as a glioma treatment. However, while bevacizumab effectively inhibits angiogenesis, it has also been reported to induce invasive proliferation. This study examined gene expression in glioma cells to investigate the mechanisms of bevacizumab-induced invasion. We made a human glioma U87ΔEGFR cell xenograft model by stereotactically injecting glioma cells into the brain of animals. We administered bevacizumab intraperitoneally three times per week. At 18 days after tumor implantation, the brains were removed for histopathology and mRNA was extracted. In vivo, bevacizumab treatment increased glioma cell invasion. qRT-PCR array analysis were perfomed. Eighteen days after tumor implantation, U87ΔEGFR mouse models treated with bevacizumab or PBS were sacrificed (n=3 to 4 per group). RNA analysis was conducted with an Extracellular Matrix & Adhesion Molecules RT Profiler PCR Array (PAHS-013Z) (QIAGEN; Hilden, Germany), according to the manufacturer’s instructions. Expression of genes encoding 84 human cell adhesion molecules and ECM components was evaluated in brain tumor tissue after bevacizumab treatment relative to control (PBS).