Treatment of MDA-MB-435 with 5-aza-2'-deoxycitidine, the most commonly used demethylation agent, obviously restored TFPI-2 expression in a concentration-dependent manner (Figure 4b, c), indicating that the down regulation of TFPI-2 in breast cancer cells is related with DNA hypermethylation. This evidence concerns the gene TFPI2 and breast carcinoma.