A novel angiogenesis model for screening anti-angiogenic compounds: The chorioallantoic membrane/feather bud assay

Abstract

Abstract. Enhanced angiogenesis is a hallmark of solid tumors and hematological malignancies. Anti-angiogenic therapeutic approaches have recently been shown to be effective for the treatment of certain cancers. Endothelial cells migrating to tumors provide them with new blood vessels that are critical for their growth and survival. We have developed a novel and rapid method to evaluate the anti-angiogenic activity of new agents consisting of a combined chorioallantoic membrane (CAM) and feather bud (FB) assay. Unlike previous assays, this new assay assesses the effects of drugs on the ability of tissues to attract and develop their own blood supply. The CAM already has a well-developed vascular network that is capable of providing blood vessels to the non-vascularized FB, allowing for this tissue to develop feathers. As a result, the exposure of the FB to drugs for 2 days followed by attachment to the CAM for 4 days allows evaluation of the compound's ability to impact blood vessel and feather formation within the CAM-attached FB tissue. Feather formation is determined as well as expression of endothelial cell genes and proteins analyzed. Using agents with known anti-angiogenic activity including fumagillin, minocycline, zoledronic acid, doxorubicin and agents lacking anti-angiogenic activity such as melphalan, we have shown that the CAM/FB assay can accurately and rapidly assess the ability of agents to prevent blood vessel and feather development within non-vascularized tissues.

Chorioallantoic Membrane Models of Various Avian Species: Differences and Applications

“…Chen et al evaluated the ability of several substances whose proangiogenic properties (fumagilin, minocycline, zoledronic acid, doxorubicin) have already been experimentally proven to induce the development of blood vessels and their subsequent outgrowth, which is accompanied by the growth of feather in previously non-vascularized avian skin. However, after four days after application, the aforementioned substances started showing a concentration-dependent inhibitory effect, especially in comparison to the controls [84].…”

“…Another type of homologous transplantation is a combined method of CAM model and feather bud (FB) assay [84,85]. It enables to determine the efficiency with which the particular substances induce vascular growth and ensure sufficient blood supply to the target tissue.…”

A Bromodomain-Containing Protein 4 (BRD4) Inhibitor Suppresses Angiogenesis by Regulating AP-1 Expression

“…The effects of all these selected compounds on angiogenesis were first determined through use of the chick embryo CAM model. The CAM assay is a well-established model for screening anti-angiogenic agents, because the ability of compounds to prevent blood vessel formation can be easily detected (Deryugina and Quigley, 2008;Chen et al, 2010). Each of the compounds (50 mg/ml) was added to the CAM of 9-day-old chick embryos for 48 h. The CAMs of chick embryos were photographed, and the inhibition ratio indicating angiogenesis was calculated and analyzed.…”