The Role of Interleukin-8 and Its Mechanism in Patients with Breast Cancer: Its Relation with Oxidative Stress and Estrogen Receptor

Context: Breast cancer is one of the leading causes of death among women all over the world. Prognostic markers can be used for patient survival. Likewise, these biomarkers are able to generate main information related to clinical manner of breast gland tumors. Interleukin-8 (IL-8) is a chemotactic cytokines caused initiation of an inflammatory response.
Evidence Acquisition: We performed a computerized search in Medline/PubMed databases with key words: IL-8, breast cancer, and oxidative stress.
IL-8 secretion motivates the expression of adhesion molecule, including fibronectin in human inflammatory breast cancer cells. IL-8 activates PI3K/Akt pathway, which in turn activates NF-κB resulted up-regulation of integrin β3 expression and increases the invasion of breast cancer cells. Therefore, it seems that IL-8/PI3K/Akt/NF-κB/integrin β3 axis may be used for therapeutic intervention of breast cancer with metastasis status. NF-κB plays an important role in IL-8 gene transcription via several signals, such as LPS, TNF-alpha, and oxidative stress. Oxidative stress caused angiogenic factor production, such as vascular endothelial growth factor and IL-8 via cancer cells. Moreover, there is inverse relation between ER level and IL-8, but the mechanism of IL-8 action in estrogen receptor-negative breast cancer is largely unknown. Estrogen receptor and growth factor in breast cancer cells is influenced by mitogen activated protein kinase (MAPK) cascade, as a part of IL-8 signaling pathway.
According to these studies, interleukin-8 may be as a main biomarker for breast cancer. It seems that signaling pathway of IL-8 may be used for therapeutic intervention of breast cancer. Also oxidative stress and breast cancer cells with lacking estrogen receptor generate more interleukin-8.