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 flesh 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 FOXP~3.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% ).Condusion 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.