ID1 and gastric cancer: Reduced expressions of Id-1 and Id-3 have been demonstrated to inhibit the metastatic ability of gastric cancer cells (Tsuchiya et al, 2005), and Id-1 expression has been shown to be associated with the presence of invasion in endometrial carcinoma (Takai et al, 2001) and tumour angiogenesis in human pancreatic cancer (Lee et al, 2004).