Similar to other integrin-targeting strategies, disintegrins have previously shown good efficacy in animal cancer models with favorable pharmacological attributes and translational potential. Nonetheless, these polypeptides are notoriously difficult to produce recombinantly due to their particular structure requiring the correct pairing of multiple disulfide bonds for biological activity. Here, we show that a sequence-engineered disintegrin (called vicrostatin or VCN) can be reliably produced in large scale amounts directly in the oxidative cytoplasm of Origami B E.
View Article and Find Full Text PDFContortrostatin (CN) (Mr 13,500 Da) is a novel homodimeric disintegrin isolated from the venom of Agkistrodon contortrix contortrix (Southern Copperhead) snake and displays two RGD motifs (one on each chain), which modulate its interaction with integrins on tumor cells and angiogenic vascular endothelial cells. In previous studies, we have shown that native CN administered in a liposomal formulation exhibits potent anti-angiogenic and tumor growth inhibitory activities. Current isolation of the protein from crude venom is difficult and prohibitively expensive for translation into the clinic.
View Article and Find Full Text PDFPathophysiol Haemost Thromb
July 2006
Disintegrins are soluble peptides found in snake venom. They bind to Arg-Gly-Asp (RGD)-responsive integrins with high affinity (nM range) and block integrin function. Contortrostatin (CN), the disintegrin from southern copperhead venom, is a homodimer with a molecular weight of 13,500.
View Article and Find Full Text PDFObject: Adenovirus vector (AdV)-mediated gene delivery has been recently demonstrated in clinical trials as a novel potential treatment for malignant gliomas. Combined coxsackievirus B and adenovirus receptor (CAR) has been shown to function as an attachment receptor for multiple adenovirus serotypes, whereas the vitronectin integrins (alphavbeta3 and alphavbeta5) are involved in AdV internalization. In resected glioma specimens, the authors demonstrated that malignant gliomas have varying levels of CAR, alphavbeta3, and alphavbeta5 expression.
View Article and Find Full Text PDFTherapeutic targeting of the tumor vasculature that destroys preexisting blood vessels of the tumor and antiangiogenesis therapy capitalize on the requirement of tumor cells on an intact vascular supply for oxygen and nutrients for growth, expansion and metastasis to the distal organs. Whereas these classes of agents show promise in delaying tumor progression, they also create glucose and oxygen deprivation conditions within the tumor that could trigger unintended prosurvival responses. The glucose-regulated protein GRP78, a major endoplasmic reticulum chaperone, is inducible by severe glucose depletion, anoxia, and acidosis.
View Article and Find Full Text PDFDespite significant research in this area, metastatic breast cancer remains a disease with a poor prognosis. Until an effective therapy is developed, it is imperative that new treatment modalities be investigated. In this report, we describe an effective method for delivery of a novel snake venom disintegrin, contortrostatin (CN), in an orthotopic, xenograft model of human mammary cancer in immunodeficient mice.
View Article and Find Full Text PDFType VII collagen is a major component of anchoring fibrils, attachment structures that mediate dermal-epidermal adherence in human skin. Dystrophic epidermolysis bullosa (DEB) is an inherited mechano-bullous disorder caused by mutations in the type VII collagen gene and perturbations in anchoring fibrils. In this study, we produced recombinant human type VII collagen in stably transfected human 293 cell clones and purified large quantities of the recombinant protein from culture media.
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