The transcription factor FOXP3 is specifically expressed in regulatory T (Treg) cells and appears to mediate immune surveillance. Indeed, FOXP3(+)Treg cells have been linked to disease pathogenesis, including some cancers. This study investigated the presence of FOXP3(+)Treg cells in colorectal cancer and the relationship of FOXP3 expression with clinicopathological features of colorectal cancer. Immunohistochemistry was used to detect expression of FOXP3 in 63 samples of colorectal cancer and 20 samples of healthy colorectal tissue; flow cytometry was used to detect FOXP3(+)Treg cells in peripheral blood. FOXP3 was more commonly expressed in colorectal cancer tissues than in normal colorectal tissues (P < 0.05). Similarly, the percentage of FOXP3(+)Treg cells in the peripheral blood was higher in patients with colorectal cancer than in control individuals (P < 0.05). The expression of FOXP3 was positively correlated with gender, Dukes staging, and lymph node metastasis. Further, expression increased with the increasing degree of malignancy (P < 0.05). Thus, FOXP3 expression may represent a valuable index in evaluating the degree of malignancy, clinicopathologic staging, and lymph node metastasis in colorectal cancer. Further, detection of FOXP3(+)Treg cells may be useful in predicting invasion, metastasis, and prognosis of patients with colorectal cancer.
Keywords: Colorectal cancer; flow cytometry; fork-head/winged helix transcription factor 3; immunohistochemistry; regulatory T cells.