In an analysis of 1200 cancer-related genes in ER + ovarian cancer cell lines, PEO1, TNFDF1, FOSL1, TRAP1, cathepsin D, and TFAP4 were found to be upregulated in response to insult with estrogens (O'Donnell et al., 2005; Chien et al., 1999; Hall and Korach, 2003). This evidence concerns the gene CTSD and ovarian cancer.