Then, FFINAL was selected for further in vitro anti-proliferative assay against a panel of human breast tumor cells and non-tumor cells (MCF-7 (estrogen-dependent mammary adenocarcinoma), MCF-7 BUS (mammary adenocarcinoma overexpressing estrogen receptor), MDA-MB 231 (negative triple mammary adenocarcinoma) and MCF-710A (non-tumoral breast cells)). This evidence concerns the gene ESR1 and breast neoplasm.