A Standardized Evaluation Method for FOXP3+ Tregs and CD8+ T-cells in Breast Carcinoma: Association With Breast Carcinoma Subtypes, Stage and Prognosis

Abstract

Background/Aim: The role of FOXP3+ Tregs and CD8+ T-cells in different stages and subtypes of breast carcinoma (BC) is yet to be fully defined, mainly because of methodological variations between studies. The aim of this study was to assess FOXP3+ and CD8+ intratumoral stromal TILs (sTILs) by a standardized method, in order to discern differences between the histological subtypes and BC stage and evaluate the applicability of the method. Patients and Methods: FOXP3+ and CD8+ sTILs were studied immunohistochemically in 207 BCs and counted on digital images, amounting to a standard stromal area of a 10×10 grid on ×40 magnification. The results were correlated with clinicopathological features and outcomes. Results: Tregs and CD8+ TILs were more abundant in HER2+ BCs (p=0.02, p=0.007, respectively), estrogen receptor (ER)-BCs (p<0.001, for both cell types), and triple-negative BCs (TNBCs) (p=0.01, p=0.006, respectively). Tregs and CD8+ TILs were associated with high grade (p<0.001 and p=0.002, respectively) and high Ki67 index (p<0.001, for both cell types). Lower CD8/FOXP3 ratio was associated with node metastases (p=0.007). Node metastases and advanced stage paralleled with decreased CD8+ sTILs (p=0. 023, p=0.019, respectively). In the entire group and in ER-BCs, CD8+ TILs were associated with favorable distant metastasis-free survival (p=0.021, p<0.001, respectively), disease-free survival (p=0.022, p<0.001, respectively) and breast cancer specific survival (BCSS) (p=0.022, p=0.005). In ER-BCs, Tregs were associated with favorable BCSS (p=0.02). Conclusion: Tregs and CD8+ TILs are higher in early-stage TNBCs and HER2+ BCs and diminish with progression to advanced stages. The findings provide support for immunotherapeutic manipulation of TILs, particularly in early stages of these BC subtypes. The evaluation methodology can be easily implemented for standardization of immunohistochemically-detected TILs.

Profiles of tumor‑infiltrating immune cells in renal cell carcinoma and their clinical implications

“…A high proportion of infiltrated Tregs in RCC may therefore indicate a worse outcome, which is similar to the CIBERSORT findings from the present study. Furthermore, the present study demonstrated that the proportion of Tregs was associated with tumor grade and TNM classification, which was also the case for other cancer types (34,35). In addition, the results from IHC demonstrated that FOXP3 expression in Tregs was increased in RCC samples compared with that in adjacent tumors.…”

Tumor Microenvironment: Key Players in Triple Negative Breast Cancer Immunomodulation

“…They found that TNBC patients with a high CD8 + TILs level or high CD8/Foxp3 ratio in residual tumors exhibit significantly favorable recurrence-free survival (RFS) and breast cancer-specific survival (BCSS) [101]. Another study also showed that CD8 + TILs were related to favorable DMFS, DFS, and BCSS in the entire 207 breast cancer group and in 56 TNBC group [102]. BRCA1-IRIS overexpressing (IRISOE) TNBC carcinomas had more CD25 + /Foxp3 + Tregs and few CD8 + /PD-1 + cytotoxic T-cells, which showed that the interaction between macrophages and IRISOE cells initiated an immunosuppressive TME within TNBC tumors [71].…”

PD-L1 Expression and Tumor-infiltrating Lymphocytes in Breast Cancer: Clinicopathological Analysis in Women Younger than 40 Years Old

“…The latter knowledge in combination with perceiving the cancer -immunity cycle, has led numerous studies to focus on the tumor microenvironment of the host in several solid cancers, including IBC (15,16). Over the decades, it has been proven that the presence of high tumor infiltrating lymphocytes (TILs) in solid tumors, such as lung, ovarian cancer, colorectal cancer, renal cell carcinoma, prostate cancer and head and neck cancers, as well as in breast cancer, is associated with better prognosis (17)(18)(19)(20)(21)(22)(23)(24)(25).…”