Distribution of CD4~+CD25~+FOXP3~+ regulatory T cells and their subsets in colorectal carcinoma and the clinical significance / 中国免疫学杂志

ABSTRACT

Objective:To determine the distribution of CD4+CD25+FOXP3+ regulatory T cells (Treg) and Treg subsets in human colorectal carcinoma microenvironment and to explore their correlation with conventional clinico-pathological features.Methods:Frozen sections and Immunohistochemistry (IHC) were used to detect FOXP3+ Treg in fresh specimen collected from 42 patients with colorectal carcinoma.The number of FOXP3+ Treg was evaluated in terms of its association with clinico-pathological feature in tumor and peri-cancer tissue.Double staining was performed to determine the expression of ICOS and FOXP3.Results:The number of FOXP3+ Treg in the colorectal carcinoma (mean 24.1) was significantly higher than that in peri-cancer tissue (mean 0.7).A higher number of tumor infiltrating FOXP3+ Tregs was found in the patient groups with poor differentiation,lymphatic metastasis and non-distant metastasis as compared to the patient groups with well differentiation,non-lymphatic metastasis and distant metastasis.The percentage of FOXP3+ ICOS+ Treg was higher in colorectal carcinoma(81%) than that in peri-cancer tissue(10%).Conclusion:Increased FOXP3+ Treg may influence the occurrence and development of colorectal carcinoma.Our data support the hypothesis that tumor infiltrating FOXP3+ Tregs attenuate the immune response against cancer and suggest that strategy to overcome FOXP3+ Treg function may be beneficial in the treatment of human colorectal cancer.