Anti-angiogenic activity of azathioprine

Azathioprine (AZA) is the main drug used in immunomodulatory therapy in post-transplant patients or with autoimmune diseases. However, no study has evaluated the AZA angiogenic response. Therefore, this study investigated the effects of AZA on the angiogenic process through macroscopic, histological, and immunohistochemical analyses in chick embryo chorioallantoic membrane (CAM). Our results showed potent anti-angiogenic activity of AZA at the higher concentrations tested in the CAM assay. The histological analysis of CAM confirmed this effect, since AZA induced a significant reduction in all parameters evaluated. In addition, immunohistochemical evaluation of CAM revealed that AZA decreased TGF-β and VEGF levels, important cytokines involved in the angiogenic process. Therefore, the AZA anti-angiogenic effect identified in our study provides new information for the possible application of this drug in anticancer treatment. •Angiogenic response of AZA was assessed in vivo by CAM assay.•VEGF, TGF-β and TNF-α levels in CAM were assessed by immunohistochemistry.•AZA showed potent antiangiogenic activity and decreased VEGF and TGF-β levels.