It is commonly overexpressed in the breast cancer microenvironment, promoting tumor growth and enhancing invasive and metastatic properties in both hormone‐positive and hormone‐negative patients.[22] However, the role of increased IL‐8 secretion in the TME due to endothelial cells and its correlation with tamoxifen resistance in breast cancer has not been previously elucidated. This evidence concerns the gene CXCL8 and breast cancer.