Several differentially expressed mRNAs in HER2-positive breast cancer (including CXCL2, CXCL12, CXCL10, CXCL11, CXCL9 and CXCL14) were enriched in the biology processes of chemokine receptor binding and chemokine activity. The gene discussed is CXCL2; the disease is breast carcinoma.