Potent and long-term antiangiogenic efficacy mediated by FP3-expressing oncolytic adenovirus.

Various ways to inhibit vascular endothelial growth factor (VEGF), a key facilitator in tumor angiogenesis, are being developed to treat cancer. The soluble VEGF decoy receptor (FP3), due to its high affinity to VEGF, is a highly effective and promising strategy to disrupt VEGF signaling pathway. Despite potential advantage and potent therapeutic efficacy, its employment has been limited by very poor in vivo pharmacokinetic properties. To address this challenge, we designed a novel oncolytic adenovirus (Ad) expressing FP3 (RdB/FP3). To demonstrate the VEGF-specific nature of RdB/FP3, replication-incompetent Ad expressing FP3 (dE1/FP3) was also generated. dE1/FP3 was highly effective in reducing VEGF expression and functionally elicited an antiangiogeneic effect. Furthermore, RdB/FP3 exhibited a potent antitumor effect compared with RdB or recombinant FP3. Consistent with these data, RdB/FP3 was shown to greatly decrease VEGF expression level and vessel density and increase apoptosis in both tumor endothelial and tumor cells, verifying potent suppressive effects of RdB/FP3 on VEGF-mediated tumor angiogenesis in vivo. Importantly, the therapeutic mechanism of antitumor effect mediated by RdB/FP3 is associated with prolonged VEGF silencing efficacy and enhanced oncolysis via cancer cell-specific replication of oncolytic Ad. Taken together, RdB/FP3 provides a new promising therapeutic approach in the treatment of cancer and angiogenesis-related diseases.

Choi IK ，Shin H ，Oh E ，Yoo JY ，Hwang JK ，Shin K ，Yu DC ，Yun CO ... -  《-》

VEGF-specific short hairpin RNA-expressing oncolytic adenovirus elicits potent inhibition of angiogenesis and tumor growth.

Yoo JY ，Kim JH ，Kwon YG ，Kim EC ，Kim NK ，Choi HJ ，Yun CO ... -  《MOLECULAR THERAPY》

Novel cancer antiangiotherapy using the VEGF promoter-targeted artificial zinc-finger protein and oncolytic adenovirus.

Kang YA ，Shin HC ，Yoo JY ，Kim JH ，Kim JS ，Yun CO ... -  《-》

pH-sensitive oncolytic adenovirus hybrid targeting acidic tumor microenvironment and angiogenesis.

Although oncolytic adenoviruses (Ads) are an attractive option for cancer gene therapy, the intravenous administration of naked Ad still encounters unfavorable host responses, non-specific interactions, and heterogeneity in targeted cancer cells. To overcome these obstacles and achieve specific targeting of the tumor microenvironment, Ad was coated with the pH-sensitive block copolymer, methoxy poly(ethylene glycol)-b-poly(l-histidine-co-l-phenylalanine) (PEGbPHF). The physicochemical properties of the generated nanocomplex, Ad/PEGbPHF, were assessed. At pH6.4, GFP-expressing Ad/PEGbPHF induced significantly higher GFP expression than naked Ad in both coxsackie and adenovirus receptor (CAR)-positive and -negative cells. To assess the therapeutic efficacy of the Ad/PEGbPHF complex platform, an oncolytic Ad expressing VEGF promoter-targeting transcriptional repressor (KOX) was used to form complexes. At pH6.4, KOX/PEGbPHF significantly suppressed VEGF gene expression, cancer cell migration, vessel sprouting, and cancer cell killing effect compared to naked KOX or KOX/PEGbPHF at pH7.4, demonstrating that KOX/PEGbPHF can overcome the lack of CAR that is frequently observed in tumor tissues. The antitumor activity of KOX/PEGbPHF systemically administered to a tumor xenograft model was significantly higher than that of naked KOX. Furthermore, KOX/PEGbPHF showed lower hepatic toxicity and did not induce an innate immune response against Ad. Altogether, these results demonstrate that pH-sensitive polymer-coated Ad complex significantly increases net positive charge upon exposure to hypoxic tumor microenvironment, allowing passive targeting to the tumor tissue. It may offer superior potential for systemic therapy, due to its improved tumor selectivity, increased therapeutic efficacy, and lower toxicity compared to naked KOX.

Choi JW ，Jung SJ ，Kasala D ，Hwang JK ，Hu J ，Bae YH ，Yun CO ... -  《-》

Soluble vascular endothelial growth factor decoy receptor FP3 exerts potent antiangiogenic effects.

Yu DC ，Lee JS ，Yoo JY ，Shin H ，Deng H ，Wei Y ，Yun CO ... -  《-》