Importantly, we found that breast cancer-derived CXCL1-3 and CXCL8 bind to the receptor CXCR2 and activate the ERK1/2 signaling pathway to initiate the expression of LIF by activating transcription factors NF-κB and Stat3 in CAAs in paracrine manner. This evidence concerns the gene CXCR2 and breast cancer.