EDN1 and cancer: Furthermore, ET-1 is mitogenic to cancer cells, and has anti-apoptotic and tumour-enhancing effects (Spinella et al, 2002; Nelson et al, 2003; Ferrara, 2004; Bagnato and Rosano, 2008), mediated by the endothelin-A-receptor (ETAR) (Pflug et al, 2007).