CTSD and breast cancer: This study aimed to evaluate the effect of CUR and E2 in the MCF-7 human breast cancer cell line on cell proliferation, anchorage independence, and BCL2 and BAX protein expression; the expression of genes associated with the epithelial-mesenchymal transition, such as β-catenin and Vimentin; and other estrogen-responsive genes such as cyclin D1, EGFR, cathepsin D, and BCL2 expression levels in comparison with the control, and is to be complemented by bioinformatics from clinical studies in breast cancer patients.