Abstract Loss of epithelial cell polarity and tissue disorganization are hallmarks of carcinogenesis. in which Ca2+ signaling plays a significant role. Here we demonstrate that the plasma membrane Ca2+ pump PMCA4 (ATP2B4) is downregulated in luminal breast cancer. and this is associated with shorter relapse-free survival in patients with luminal A and B1 subtype tumors. https://seisukeknifes.shop/product-category/sharpening-stone/