EXTH-04. COMBINATION OF BEVACIZUMAB ENHANCES THE ANTI-TUMOR EFFICACY OF AD-SGE-REIC FOR GLIOMA

Abstract Reduced expression in immortalized cells/Dickkopf-3 (REIC/Dkk-3) is a tumor suppressor gene and its overexpression has been shown to exert anti-tumor effects as a therapeutic target gene in many human cancers. Recently, we revealed the anti-glioma effects of an adenoviral vector carrying REIC/Dkk-3 with the super gene expression system (Ad-SGE-REIC) and conducted the phase Ⅰ/Ⅱ a clinical trial for recurrent malignant glioma (jRCT2063190013). Anti-vascular endothelial growth factor treatments such as bevacizumab have demonstrated convincing therapeutic efficacy in patients with glioma. In this study, we examined the effects of Ad-SGE-REIC on glioma treated with bevacizumab in vitro and in vivo. Ad-SGE-REIC treatment resulted in a significant reduction in the number of invasion cells treated with bevacizumab. Western blot analyses revealed the increased expression of several endoplasmic reticulum stress markers in cells treated with both bevacizumab and Ad-SGE-REIC, as well as decreased β-catenin protein levels. In glioma-bearing mouse models, survival was extended in the combination therapy group. These results suggest that the combination therapy of Ad-SGE-REIC and bevacizumab showed anti-glioma effects by suppressing the angiogenesis and invasion of tumor cells. Combined Ad-SGE-REIC and bevacizumab might be a promising strategy for the treatment of malignant glioma.