The expression of chemokine receptors CCR6, CXCR2 and CXCR4 is not organ‐specific for distant metastasis in colorectal cancer: a comparative study

Abstract

The liver and lung are the organs most commonly affected by metastasis in colorectal cancer (CRC), and the interaction of chemokines and chemokine receptors (CKRs) plays an important role in the metastatic process. The aim of this study was to investigate the organ specificity of CKRs in CRC distant metastasis. Surgical specimens of primary tumours from 46 patients with metachronous distant metastases were retrieved retrospectively (20 lung metastases; 26 liver metastases). As a control, the records of 29 patients without distant metastases were randomly retrieved from our database, and their specimens were reassessed. The expression rates of CKRs, including CCR6, CXCR2, and CXCR4, were determined by immunohistochemistry, and were compared among the groups. The expression rates of CCR6 and CXCR2 were both significantly higher in the metastasis group than in the non-metastasis group (P < 0.05), but there was no statistical difference between the lung metastasis and liver metastasis subgroups. The expression of CXCR4 was not significantly different between the metastasis and non-metastasis groups. Multivariable analysis suggested that preoperative serum carcinoembryonic antigen level, CCR6 and CXCR2 were independent factors associated with distant metastasis. The expression of CCR6 and CXCR2 in CRC could predict metachronous distant metastasis, but they have no organ specificity for metastasis.