C-X-C Chemokine Receptor Type 7 (CXCR-7) Expression in Invasive Ductal Carcinoma of Breast in Association with Clinicopathological Features.

C-X-C chemokine receptor type 7 (CXCR-7) is an atypical receptor for chemokines whose role in different stages of carcinogenesis has been evaluated in breast cancer cell lines and animal models. Moreover, it has been demonstrated to be a target of regulation by the tumor suppressor microRNA (miR)-100. In the present study, we assessed CXCR-7 expression in 60 breast cancer patients in association with clinicopathological and demographic data of patients. We also extracted the results of our previous work on miR-100 expression in the same cohort of patients to assess the correlation between miR-100 and CXCR-7 expression levels. Transcript levels of CXCR-7 were significantly higher in tumoral tissues compared with adjacent non-cancerous tissues (ANCTs) (Tumoral vs. ANCTs: 3.64 ± 1.8 vs. 0.73 ± 1.3, P = 0.000). A significant negative correlation was detected between CXCR-7 protein and miR-100 transcript levels (r = -0.526, P < 0.05). High CXCR-7 mRNA levels were significantly associated with tumor size (P = 0.01). Besides, high protein levels were more prevalent in higher TNM stages (P = 0.000). Moreover, high CXCR-7 protein levels were significantly associated with ER (P = 0.005) and PR (P = 0.02) status. The present work provides further evidence for the role of CXCR-7 in breast cancer and proposes the elimination of inhibitory effects of miR-100 on CXCR-7 expression as a mechanism for its up-regulation in breast cancer tissues.