Abstract 3476: Combined blockade of IGF-I receptor and VEGF for gastric cancer

Abstract

Abstract Background Insulin-like growth factor-I receptor (IGF-IR) signaling is required for tumorigenicity and tumor progression of gastrointestinal (GI) cancers. We have shown successful therapy for GI cancers using adenoviruses expressing dominant negative IGF-IR (IGF-IR/dn). On the other hand, IGF-IR signaling affects on vascular endotherial growh factor (VEGF) expression in some tumors. Here, we sought to evaluate the roles of IGF-IR on tumor angiogenesis and lymphangiogenesis and to develop targeting therapy for gastric cancer. Methods The impact of IGF signals on VEGF-A/C expression in gastric cancer cell was assessed. The effects of IGF-IR/dn alone and with bevacizumab on angiogenesis / lymphangiogenesis in mouse xenogfarts were assessed. Results IGFs induced expressions of VEGFs and up-regulated in vitro vascular vessel formation. IGF-IR/dn reduced those expressions and vascular formation. IGF-IR/dn down-regulated tumor size on mice via inhibiting both angiogenesis and lymphangiogenesis. The combination of IGF-IR/dn and bevacizumab was highly effective against tumors on mice. This combination reduced the expression of VEGF and induced apoptosis in the murine tumors most of all. Conclusions IGF-IR is involved in angiogenesis and lymphangiogenesis in gastric cancer. Targeting IGF-IR alone and with blocking VEGF may have therapeutic utility of prevention for gastric cancer progression. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 3476.