Tumor-infiltrating lymphocytes contain a higher proportion of FOXP3+ T lymphocytes in cervical cancer

Background/Purpose: The subpopulations and functions of tumor-infiltrating lymphocytes (TILs) from cervical cancer (CC) are altered. Dysfunction of TIL could be partially because of the inhibition by regulatory T (T _reg) cells. FOXP3 is the control gene for the T _reg cells. Methods: We investigated the distribution of TILs and FOXP3 ⁺ cells in CC (n = 10) and cervical intraepithelial neoplasia (n = 8) tissues. Double-immunofluorescence and confocal-based image quantitative microscopic analysis were used to calculate the number of cluster of differentiation (CD)4 ⁺CD25 ⁺FOXP3 ⁺ T _reg cells around the tumor cells. Results: The CD4 ⁺CD25 ⁺FOXP3 ⁺ phenotype of T _reg cells was accumulated around the tumor cells. CC contains a significantly higher proportion of the FOXP3 ⁺ T cells than in cervical intraepithelial neoplasia (p < 0.001). Moreover, CC with lymph node metastasis has a higher proportion of the FOXP3 ⁺ T cells than that without lymph node metastasis (p < 0.05). Conclusion: The increased accumulation of T _reg cells suggests that T _reg cells are important in the immunopathogenesis of CC.