In contrast to basal breast cancer cell line differences, PMCA2 levels were not significantly different between the recently defined triple-negative breast cancer (TNBC) molecular subtypes, BLIS, BLIA, LAR and MES (Fig. 4A) and there was no significant distribution of tumor subtypes in the low and high PMCA2 expression groups (Fig. 4B). This evidence concerns the gene ATP2B2 and breast cancer.