In breast tissue, both AT1 and AT2 receptors are present, and the AT1 is located in both lobular and ductal epithelial cells in normal and benign breast tissues (Inwang et al, 1997), and increased AT1 receptor mRNA transcription has been shown in cancer as compared with normal cells (Greco et al, 2002a), although receptor expression may decrease in invasive carcinoma, compared with hyperplasia or ductal carcinoma in situ (De Paepe et al, 2001). Here, AGTR1 is linked to ductal breast carcinoma in situ.