A comparison of histone modifications in the promoter region of the ATP2C2 gene encoding SPCA2 between normal human mammary epithelial cells (HMEC) and the breast cancer cell line MCF-7 revealed significant elevation of H3K27 histone acetylation in the tumor cells corresponding to high expression of SPCA2 in this cell line [29] (Figure S1A,B). This evidence concerns the gene ATP2C2 and breast cancer.