Some studies suggest that Ang-1 may be pro-angiogenic (Suri et al, 1998; Hansbury et al, 2001; Shim et al, 2001), whereas others have shown that Ang-1 inhibits angiogenesis, tumour growth and vascular permeability (Chae et al, 2000; Hayes et al, 2000; Thurston et al, 2000; Ahmad et al, 2001; Tian et al, 2002). The gene discussed is ANGPT1; the disease is neoplasm.