CXC receptor 4 and stromal cell–derived factor 1 in primary tumors and liver metastases of colorectal cancer

BackgroundIt has been determined that the chemokine receptor CXC receptor 4 (CXCR4) and its ligand, stromal cell-derived factor 1 (SDF-1), regulate several key processes in a wide variety of cancers. In this study, we investigate the possible role of SDF-1 (noncancerous liver tissue) and CXCR4 in liver metastases of colorectal cancer (CRC).Materials and methodsReverse transcription–polymerase chain reaction was performed to examine the expression of SDF-1 in noncancerous liver tissues of 16 CRC patients with liver metastasis and in normal liver tissues of six patients with benign liver disease. We also examined the expression of CXCR4 in cancerous tissues from primary and metastatic tumors.ResultsUsing reverse transcription–polymerase chain reaction, CXCR4 expression in metastatic tumors tended to be higher than that in primary tumors (P = 0.16). High CXCR4 expression in a primary tumor was found to be related to an increased lymphatic invasion (P = 0.01), an advanced depth of tumor invasion (P = 0.07), and a decrease in the overall survival rate. The SDF-1 expression observed in noncancerous liver tissues of CRC with liver metastasis was significantly higher than that observed in normal liver tissues of benign liver disease (P < 0.05).ConclusionsIn CRC with liver metastasis, CXCR4 expression demonstrated associations with local progression, liver metastasis, and poor overall survival.