Chemokine (C-X-C motif) ligand 1 (CXCL1) protein expression is increased in high-grade prostate cancer

Chemokines, including chemokine (C-X-C motif) ligand 1 (CXCL1), may enhance tumor epithelial-stromal interactions facilitating tumor growth and invasion. Studies have linked CXCL1 expression to gastric, colon and skin cancers, however, no study to date has been reported describing CXCL1 in human prostate tumors. Herein, we set out to describe the expression pattern of CXCL1 in human prostate tumors. Utilizing a commercial tissue microarray, immunohistochemical staining was used to monitor CXCL1 protein expression in 90 primary prostate tumors and 20 benign prostate tissues. CXCL1 protein expression was noted to be predominantly in the cytoplasm of both the benign epithelia glands and cancerous epithelia glands) with >75% of benign or cancerous glands demonstrating immunoreactivity. However, staining intensity was noted to be significantly different between benign and cancerous tissue with 84% of cancerous tissue staining moderate (++) to strong (+++) compared to only 30% of benign prostate samples staining moderate (++) to strong (+++) (p<0.0001). Increased CXCL1 protein levels were associated with higher-grade tumors (Gleason≤6 vs. Gleason score 7-10, p=0.038). An increase in CXCL1 protein was present in of high-grade malignancy. Further studies are warranted to clearly define the role of CXCL1 in prostate cancer.