Selective recruitment and retainment of regulatory T cells in human colorectal cancer

• Published in: The Lancet (British edition) 2013-02, Vol.381, p.S113-S113
• Main Authors: Ward, ST, Hepburn, E, Li, K, Curbishley, SM, Hejmadi, R, Ismail, T, Bicknell, R, Rot, A, Adams, DH
• Format: Article
• Language: English
• Subjects: biomedical research; chemokines; chemotaxis; coculture; Colorectal carcinoma; colorectal neoplasms; endothelium; flow cytometry; humans; Immune response; Immunotherapy; Infiltration; Internal Medicine; lymph nodes; Lymphocytes; Medical research; patients; phenotype; quantitative polymerase chain reaction; receptors; recruitment; resection; T-lymphocytes; transcription factors; Tumors; Western blotting
• ISSN: 0140-6736; 1474-547X
• DOI: 10.1016/S0140-6736(13)60553-X

Abstract Background Colorectal cancer (CRC) is the third most common malignancy in the UK, and lymphocytic infiltration is associated with improved survival. Analysis of lymphocytic infiltration yields a prognostic ability rivalling the TNM tumour staging system. Regulatory T cells (Treg) are known to be enriched in CRC, and it is postulated that they promote immunological tumour escape by suppression of effector T-cell responses. Little is known about the signals controlling entry of Treg into CRC. Methods Matched CRC, distal colonic tissue, draining lymph node, and blood were obtained from patients undergoing resection of CRC. Tumour-infiltrating lymphocytes were isolated and phenotyped for chemokine receptors with flow cytometry. The presence of tissue chemokines was analysed with real-time PCR and western blotting. Standard chemotaxis and suppression assays were performed. Peripheral blood lymphocytes were co-cultured with tumour supernatant, and effects on lymphocyte phenotype were assessed. Findings The proportion of T cells with a Treg phenotype was significantly increased in CRC compared with that in colonic tissue (14·8% vs 5·1%, p