Objective To investigate the synergistic effects of rosiglitazone on the growth of transplanted human colon cancer cells in nude mice.Methods Human colon cancer cells were transplanted into nude mice,and twenty xenografts were established successively.They were then randomly divided into 5 groups.Different treatments were served from the 4th day,and all mice were sacrificed after 29 days.The volumes of the transplanted tumors were measured every 4 days during the therapy.The expression of PPARγ,NF-κB,Bcl-2,Bax protein were analized by Western blot.Results In each treatment group,tumor growth was suppressed significantly by intraperitoneal Rosiglitazone and their combination resulted in a significant inhibition on the growth of human colon cancer in vivo.Western blot results showed that HT-29 cells treated with ROZ reduced NF-κB、Bcl-2 proteins expression and increased Bax proteins expression via activating PPARγ protein,in a concentration dependent manner.Conclusion The chemosenitization of rosiglitazone might be associated with downregulation expression of NF-κB,Bcl-2 protein and upregulation expression of Bax protein via activating of PPARγ.

CT-322 is a new anti-angiogenic therapeutic agent based on an engineered variant of the tenth type III domain of human fibronectin, i.e., an AdnectinTM, designed to inhibit vascular endothelial growth factor receptor (VEGFR)-2. This PEGylated Adnectin was developed using an mRNA display technology. CT-322 bound human VEGFR-2 with high affinity (KD, 11 nM), but did not bind VEGFR-1 or VEGFR-3 at concentrations up to 100 nM, as determined by surface plasmon resonance studies. Western blot analysis showed that CT-322 blocked VEGF-induced phosphorylation of VEGFR-2 and mitogen-activated protein kinase in human umbilical vascular endothelial cells. CT-322 significantly inhibited the growth of human tumor xenograft models of colon carcinoma and glioblastoma at doses of 15-60 mg/kg administered 3 times/week. Anti-tumor effects of CT-322 were comparable to those of sorafenib or sunitinib, which inhibit multiple kinases, in a colon carcinoma xenograft model, although CT-322 caused less overt adverse effects than the kinase inhibitors. CT-322 also enhanced the anti-tumor activity of the chemotherapeutic agent temsirolimus in the colon carcinoma model. The high affinity and specificity of CT-322 binding to VEGFR-2 and its anti-tumor activities establish CT-322 as a promising anti-angiogenic therapeutic agent. Our results further suggest that Adnectins are an important new class of targeted biologics that can be developed as potential treatments for a wide variety of diseases.

Using directed in vitro protein evolution, we generated proteins that bound and antagonized the function of vascular endothelial growth factor receptor 2 (VEGFR2). Binders to human VEGFR2 (KDR) with 10-200 nM affinities were selected by using mRNA display from a library (10(13) variants) based on the tenth human fibronectin type III domain (10Fn3) scaffold. Subsequently, a single KDR binding clone (K-d = 11 nM) was subjected to affinity maturation. This yielded improved KDR binding molecules with affinities ranging from 0.06 to 2 nM. Molecules with dual binding specificities (human/mouse) were also isolated by using both KDR and Flk-1 (mouse VEGFR2) as targets in selection. Proteins encoded by the selected clones bound VEGFR2-expressing cells and inhibited their VEGF-dependent proliferation. Our results demonstrate the potential of these inhibitors in the development of anti-angiogenesis therapeutics.