In contrast to ATP2B4, no statistically significant association was detected between low and high ATP2B1 gene expression and RFS in the LUMA and LUMB1 breast carcinoma subtypes, while in the LUMB2 subtype high ATP2B1 expression (PMCA1) level was associated with a lower probability of RFS as also seen for high ATP2B4 (PMCA4) expression (Fig. 1d). This evidence concerns the gene ATP2B4 and breast carcinoma.