Increased CXCL8 Expression Is Negatively Correlated with the Overall Survival of Patients with ER-Negative Breast Cancer.

Background: C-X-C motif chemokine ligand 8 (CXCL8) is a multi-functional chemokine and has important roles during tumor formation and development. It was previously reported that increased CXCL8 protein levels occurred in certain patients. Materials and Methods: In the present study, we examined levels of CXCL8 mRNA in breast cancer tissues and analyzed its levels in correlation to patients' clinical data and 10-year overall survival (OS). Results: Our results clearly demonstrated that the level of CXCL8 mRNA was significantly higher in patients without estrogen receptor expression. The receiver operating characteristic curve indicated that the best cut-off value for CXCL8 expression was 3.095 for predicting patient's OS. Conclusion: The present study demonstrated that higher CXCL8 mRNA levels in breast cancer tissues together with estrogen receptor negativity was associated with significantly shorter OS, and could be applied as a negative risk factor for 10-year OS.