ORAI1 and breast cancer: The analysis of the expression ratio between the Orai1 variants indicates a greater expression of Orai1β in all the cell types investigated and, interestingly, a greater Orai1α/Orai1β expression ratio in MCF7 and MDA-MB-231 breast cancer cells than in non-tumoral MCF10A cells (Figure 1i; p < 0.05; n = 6).