Purpose: The forkhead box transcription factor FoxP3 is specifically expressed in T cells with regulatory properties (Treg). Recently, high numbers of Treg were described to be associated with poor survival in different malignancies. The aim of the presented study was determine the prognostic effect of FoxP3 mRNA expression (reflecting the tissue content of Treg) in ovarian carcinoma and its relation with cytokines, such as IFN-γ. Experimental Design: Total RNA was isolated from 99 ovarian carcinoma and from 14 healthy ovarian biopsies. Real-time PCR for FoxP3 was done and correlated with IFN-γ-, CD3-, IRF-1-, SOCS-1-, HER-2-, and iNOS expression as well as patients' outcome. The mRNA data was corroborated by FoxP3 immunohistochemistry. Results: Quantitation of FoxP3 expression identified a patient subgroup (>81th percentile), which is characterized by a significantly worse prognosis in terms of overall survival (27.8 versus 77.3 months, P = 0.0034) and progression-free survival (18 versus 57.5 months; P = 0.0041). FoxP3 expression correlated with IFN-γ, IRF-1, and CD3 expression. High FoxP3 expression represents an independent prognostic factor for overall survival (P = 0.004) and progression-free survival (P = 0.004). Conclusions: High expression levels of FoxP3 might represent a surrogate marker for an immunosuppressive milieu contributing to tumor immune escape. Strategies selectively depleting Treg might improve the antitumor activity of endogenously arising tumor-reactive T cells and immunotherapies using vaccines or antibodies.

Hepcidin, a master regulator of iron homeostasis, is produced in small amounts by inflammatory monocytes/macrophages. Chronic immune activation leads to iron retention within monocytes/macrophages and the development of anemia of chronic disease (ACD). We questioned whether monocyte-derived hepcidin exerts autocrine regulation toward cellular iron metabolism. Monocyte hepcidin mRNA expression was significantly induced within 3 hours after stimulation with LPS or IL-6, and hepcidin mRNA expression was significantly higher in monocytes of ACD patients than in controls. In ACD patients, monocyte hepcidin mRNA levels were significantly correlated to serum IL-6 concentrations, and increased monocyte hepcidin mRNA levels were associated with decreased expression of the iron exporter ferroportin and iron retention in these cells. Transient transfection experiments using a ferroportin/EmGFP fusion protein construct demonstrated that LPS inducible hepcidin expression in THP-1 monocytes resulted in internalization and degradation of ferroportin. Transfection of monocytes with siRNA directed against hepcidin almost fully reversed this lipopolysaccharide-mediated effect. Using ferroportin mutation constructs, we found that ferroportin is mainly targeted by hepcidin when expressed on the cell surface. Our results suggest that ferroportin expression in inflammatory monocytes is negatively affected by autocrine formation of hepcidin, thus contributing to iron sequestration within monocytes as found in ACD.

CD4⁺CD25⁺ regulatory T cells (Treg) are of critical importance for the maintenance of tolerance. The kidney is frequently involved in autoimmune diseases, such as lupus erythematosus or glomerulonephritis (GN). Therefore, the therapeutic efficacy of Treg in a T cell–dependent murine model of experimental anti–glomerular basement membrane (anti-GBM) GN was tested. Transfer of 1 × 10⁶ CD4⁺CD25⁺ T cells (day −1) into mice that were previously immunized with rabbit IgG (day −3) and subsequently received an injection of anti-GBM rabbit serum (day 0) significantly attenuated the development of proteinuria when compared with animals that received an injection of 1 × 10⁶ CD4⁺CD25⁻ T cells (control group). Treg injection induced a dramatic decrease of glomerular damage as well as a marked decrease of CD4⁺ T cell, CD8⁺ T cell, and macrophage infiltration. Of note, deposition of immune complexes was not prevented by Treg, showing that Treg rather inhibited cell-mediated organ damage than priming of the humoral immune response. Accordingly, a significant reduction of IFN-γ, TNF-α, and TGF-β1 mRNA in kidneys from animals that received Treg injection was observed. Tracking of enhanced green fluorescence protein–transgenic Treg revealed a predominant migration to secondary lymphoid organs with a significant increase of regulatory T cells (CD4⁺CD25⁺CD69⁻CD45RB^low) in the lymph nodes. In contrast, enhanced green fluorescence protein–and FoxP3-positive cells by reverse transcription–PCR and CD4⁺CD25⁺CD69⁻CD45RB^low T cells by flow cytometry in the kidney of nephritic animals were not detected. This report provides first evidence that Treg are potent suppressors of anti-GBM GN. Treg therefore might be of therapeutic value for the treatment of severe GN in humans.

Background: Metastatic colorectal cancer (mCRC) remains a lethal disease. Survival, however, is increasing due to a growing number of treatment options. Yet due to the number of prognostic factors and their interactions, prediction of mortality is difficult. The aim of this study is to provide a clinical model supporting prognostication of mCRC mortality in daily practice. Methods: Data from 1104 patients with mCRC in three prospective cancer datasets were used to construct and validate Cox models. Input factors for stepwise backward method variable selection were sex, RAS/BRAF-status, microsatellite status, treatment type (no treatment, systemic treatment with or without resection of metastasis), tumor load, location of primary tumor, metastatic patterns and synchronous or metachronous disease. The final prognostic model for prediction of survival at two and 3 years was validated via bootstrapping to obtain calibration and discrimination C-indices and dynamic time dependent AUC. Results: Age, sidedness, number of organs with metastases, lung as only site of metastasis, BRAF mutation status and treatment type were selected for the model. Treatment type had the most prominent influence on survival (resection of metastasis HR 0.26, CI 0.21–0.32; any treatment vs no treatment HR 0.31, CI 0.21–0.32), followed by BRAF mutational status (HR 2.58, CI 1.19–1.59). Validation showed high accuracy with C-indices of 72.2 and 71.4%, and dynamic time dependent AUC’s of 76.7 ± 1.53% (both at 2 or 3 years), respectively. Conclusion: The mCRC mortality prediction model is well calibrated and internally valid. It has the potential to support both, clinical prognostication for treatment decisions and patient communication.