Vasohibin aptamer (VASH-aptamer): a potential theranostic agent in colorectal cancer

Abstract

Angiogenesis is a term that describes blood vessels formation, a physiological process involved in growth and healing, which is also linked to the development of diseases, including cancer, its progression and metastasis development. Differently, tumor angiogenesis is characterized by the neovessels formation through the stimulation and proliferation of preexisting endothelial vessel cells and thus is called neo-angiogenesis. Among the most recently described angiogenesis regulators are vasohibins (VASHs). The vasohibin family is composed of two members: vasohibin-1 (VASH-1), which is expressed in vessels and in colorectal cancer and is prognostic-related, and vasohibin-2 (VASH-2), its homolog, which is expressed in the tumor tissue and seems to have a stimulatory effect on angiogenesis. Currently, antiangiogenic therapy is an option, especially in cancer advanced stages, but their side effects are still broad, due to their action in tumor endothelium and in normal endothelium. In addition, drug resistance development has been a problem. The specific target identification, such as VASH, arouses interest in antiangiogenic therapy. The project was divided into three distinct phases. In phase I (Brazil) the aim was to understand the VASH behavior in colorectal cancer (CCR) carcinogenesis from biopsies of human normal tissue, adenoma and adenocarcinoma; in phase II (Brazil) a new antiangiogenic agent has been studied in an animal model of human colon cancer, while in phase III we intend to develop an aptamer of VASH as a theranostic agent in colon cancer (Canada). (AU)