Changes in dendritic cell phenotype after a new high-dose weekly schedule of interleukin-2 therapy for kidney cancer and melanoma.
ABSTRACT High-dose intravenous interleukin-2 (IL-2) therapy (14 doses/course, 2 courses/cycle) for metastatic melanoma or kidney cancer induces infrequent, although major responses. In this trial, we evaluated a new schedule (dose of 600,000 IU/kg, 8 h between doses, 5 doses/course, 4 courses at weekly intervals/cycle) of high-dose IL-2, in which we inserted more planned breaks while maintaining high cumulative dose delivery, and investigated the relationship between dendritic cells (DC) and response to treatment. Target dose delivery was attained: median IL-2 cumulative dose per patient was 11.4 and 10.8 million units/kg (cycles 1 and 2, respectively). Major responses were observed in patients with kidney cancer (n=20; 3 complete and 2 partial responses) and melanoma (n=16; 1 partial response). Adverse events appeared comparable with those typically associated with high-dose IL-2. From this data set, we introduce the hypothesis-generating observation that patients who had more favorable outcomes had high pretreatment DC-to-myeloid-derived suppressor cell (MDSC) ratios, similar to the ratio observed in healthy individuals. However, even in patients with the most favorable outcome, after treatment, there were IL-2-induced changes in the DC-to-MDSC ratio, specifically increases in MDSCs. This modified IL-2 schedule is a feasible option, with a more uniform dose delivery over the treatment cycle, a similar toxicity profile, and observed complete, durable response in patients with renal cancer. Pretreatment assessment of DC phenotypic or maturational status may be a starting point to predicting response to high-dose IL-2 cytokine immunotherapy in patients with melanoma and kidney cancer.
SourceAvailable from: Mireille Van Gele[Show abstract] [Hide abstract]
ABSTRACT: Background Immune markers in the peripheral blood of melanoma patients could provide prognostic information. However, there is currently no consensus on which circulating cell types have more clinical impact. We therefore evaluated myeloid-derived suppressor cells (MDSC), dendritic cells (DC), cytotoxic T-cells and regulatory T-cells (Treg) in a series of blood samples of melanoma patients in different stages of disease.Methods Flow cytometry was performed on peripheral blood mononuclear cells of 69 stage I to IV melanoma patients with a median follow-up of 39 months after diagnosis to measure the percentage of monocytic MDSCs (mMDSCs), polymorphonuclear MDSCs (pmnMDSCs), myeloid DCs (mDCs), plasmacytoid DCs (pDCs), cytotoxic T-cells and Tregs. We also assessed the expression of PD-L1 and CTLA-4 in cytotoxic T-cells and Tregs respectively. The impact of cell frequencies on prognosis was tested with multivariate Cox regression modelling.ResultsCirculating pDC levels were decreased in patients with advanced (P¿=¿0.001) or active (P¿=¿0.002) disease. Low pDC levels conferred an independent negative impact on overall (P¿=¿0.025) and progression-free survival (P¿=¿0.036). Even before relapse, a decrease in pDC levels was observed (P¿=¿0.002, correlation coefficient 0.898). High levels of circulating MDSCs (>4.13%) have an independent negative prognostic impact on OS (P¿=¿0.012). MDSC levels were associated with decreased CD3+ (P¿<¿0.001) and CD3¿+¿CD8+ (P¿=¿0.017) T-cell levels. Conversely, patients with high MDSC levels had more PD-L1+ T-cells (P¿=¿0.033) and more CTLA-4 expression by Tregs (P¿=¿0.003). pDCs and MDSCs were inversely correlated (P¿=¿0.004). The impact of pDC levels on prognosis and prediction of the presence of systemic disease was stronger than that of MDSC levels.Conclusion We demonstrated that circulating pDC and MDSC levels are inversely correlated but have an independent prognostic value in melanoma patients. These cell types represent a single immunologic system and should be evaluated together. Both are key players in the immunological climate in melanoma patients, as they are correlated with circulating cytotoxic and regulatory T-cells. Circulating pDC and MDSC levels should be considered in future immunoprofiling efforts as they could impact disease management.Journal of Translational Medicine 01/2015; 13(1):9. DOI:10.1186/s12967-014-0376-x · 3.99 Impact Factor
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ABSTRACT: Immune function relies on an appropriate balance of the lymphoid and myeloid responses. In the case of neoplasia, this balance is readily perturbed by the dramatic expansion of immature or dysfunctional myeloid cells accompanied by a reciprocal decline in the quantity/quality of the lymphoid response. In this review, we seek to: (1) define the nature of the atypical myelopoiesis observed in cancer patients and the impact of this perturbation on clinical outcomes; (2) examine the potential mechanisms underlying these clinical manifestations; and (3) explore potential strategies to restore normal myeloid cell differentiation to improve activation of the host antitumor immune response. We posit that fundamental alterations in myeloid homeostasis triggered by the neoplastic process represent critical checkpoints that govern therapeutic efficacy, as well as offer novel cellular-based biomarkers for tracking changes in disease status or relapse.Cancer Immunology and Immunotherapy 11/2014; 64(1). DOI:10.1007/s00262-014-1639-3 · 3.94 Impact Factor
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ABSTRACT: BackgroundInterferon (IFN)-γ-mediated immune response plays an important role in tumor immunosurveillance. However, the regulation of IFN-γ-mediated tumorigenesis and immune response remains elusive. USP18, an interferon stimulating response element, regulates IFN-α-mediated signaling in anti-viral immune response, but its role in IFN-γ-mediated tumorigenesis and anti-tumor immune response is unknown.MethodIn this study, USP18 in tumorigenesis and anti-tumor immune response was comprehensively appraised in vivo by overexpression or downregulation its expression in murine B16 melanoma tumor model in immunocompetent and immunodeficient mice.ResultsEctopic expression or downregulation of USP18 in B16 melanoma tumor cells inhibited or promoted tumorigenesis, respectively, in immunocompetent mice. USP18 expression in B16 melanoma tumor cells regulated IFN-γ-mediated immunoediting, including upregulating MHC class-I expression, reducing tumor cell-mediated inhibition of T cell proliferation and activation, and suppressing PD-1 expression in CD4+ and CD8+ T cells in tumor-bearing mice. USP18 expression in B16 melanoma tumor cells also enhanced CTL activity during adoptive immunotherapy by prolonging the persistence and enhancing the activity of adoptively transferred CTLs and by reducing CTL exhaustion in the tumor microenvironment. Mechanistic studies demonstrated that USP18 suppressed tumor cell-mediated immune inhibition by activating T cells, inhibiting T-cell exhaustion, and reducing dendritic cell tolerance, thus sensitizing tumor cells to immunosurveillance and immunotherapy.ConclusionThese findings suggest that stimulating USP18 is a feasible approach to induce B16 melanoma specific immune response.Molecular Cancer 05/2014; 13(1):132. DOI:10.1186/1476-4598-13-132 · 5.40 Impact Factor