Summary Background A subset of patients with metastatic renal-cell carcinoma show indolent growth of metastases. Because of the toxicity and non-curative nature of systemic therapy, some of these ...patients could benefit from initial active surveillance. We aimed to characterise the time to initiation of systemic therapy in patients with metastatic renal-cell carcinoma under active surveillance. Methods In this prospective phase 2 trial, we enrolled patients with treatment-naive, asymptomatic, metastatic renal-cell carcinoma from five hospitals in the USA, Spain, and the UK. Patients were radiographically assessed at baseline, every 3 months for year 1, every 4 months for year 2, then every 6 months thereafter. Patients continued on observation until initiation of systemic therapy for metastatic renal-cell carcinoma; a decision that was made at the discretion of the treating physician and patient. The primary endpoint of the study was time to initiation of systemic therapy in the per-protocol population. The follow-up of patients is ongoing. Findings Between Aug 21, 2008, and June 7, 2013, we enrolled 52 patients. Median follow-up of patients in the study was 38·1 months (IQR 29·4–48·9). In the 48 patients included in analysis, median time on surveillance from registration on study until initiation of systemic therapy was 14·9 months (95% CI 10·6–25·0). Multivariate analysis showed that higher numbers of International Metastatic Database Consortium (IMDC) adverse risk factors (p=0·0403) and higher numbers of metastatic disease sites (p=0·0414) were associated with a shorter surveillance period. 22 (46%) patients died during the study period, all from metastatic renal-cell carcinoma. Interpretation A subset of patients with metastatic renal-cell carcinoma can safely undergo surveillance before starting systemic therapy. Additional investigation is required to further define the benefits and risks of this approach. Funding None.
The immunology of renal cell carcinoma Díaz-Montero, C Marcela; Rini, Brian I; Finke, James H
Nature reviews. Nephrology,
12/2020, Letnik:
16, Številka:
12
Journal Article
Recenzirano
Renal cell carcinoma (RCC) is the most common type of kidney cancer and comprises several subtypes with unique characteristics. The most common subtype (~70% of cases) is clear-cell RCC. RCC is ...considered to be an immunogenic tumour but is known to mediate immune dysfunction in large part by eliciting the infiltration of immune-inhibitory cells, such as regulatory T cells and myeloid-derived suppressor cells, into the tumour microenvironment. Several possible mechanisms have been proposed to explain how these multiple tumour-infiltrating cell types block the development of an effective anti-tumour immune response, including inhibition of the activity of effector T cells and of antigen presenting cells via upregulation of suppressive factors such as checkpoint molecules. Targeting immune suppression using checkpoint inhibition has resulted in clinical responses in some patients with RCC and combinatorial approaches involving checkpoint blockade are now standard of care in patients with advanced RCC. However, a substantial proportion of patients do not benefit from checkpoint blockade. The identification of reliable biomarkers of response to checkpoint blockade is crucial to facilitate improvements in the clinical efficacy of these therapies. In addition, there is a need for the development of other immune-based strategies that address the shortcomings of checkpoint blockade, such as adoptive cell therapies.
Tumors escape immune recognition by several mechanisms, and induction of myeloid derived suppressor cells (MDSC) is thought to play a major role in tumor mediated immune evasion. MDSC arise from ...myeloid progenitor cells that do not differentiate into mature dendritic cells, granulocytes, or macrophages, and are characterized by the ability to suppress T cell and natural killer cell function. They are increased in patients with cancer including renal cell carcinoma (RCC), and their levels have been shown to correlate with prognosis and overall survival. Multiple methods of inhibiting MDSCs are currently under investigation. These can broadly be categorized into methods that (a) promote differentiation of MDSC into mature, non-suppressive cells (all trans retinoic acid, vitamin D), (b) decrease MDSC levels (sunitinib, gemcitabine, 5-FU, CDDO-Me), or (c) functionally inhibit MDSC (PDE-5 inhibitors, cyclooxygenase 2 inhibitors). Recently, several pre-clinical tumor models of combination therapy involving sunitinib plus vaccines and/or adoptive therapy have shown promise in MDSC inhibition and improved outcomes in the tumor bearing host. Current clinical trials are underway in RCC patients to assess not only the impact on clinical outcome, but how this combination can enhance anti-tumor immunity and reduce immune suppression. Decreasing immune suppression by MDSC in the cancer host may improve outcomes and prolong survival in this patient population.
Purpose: Immune dysfunction reported in renal cell carcinoma (RCC) patients may contribute to tumor progression. Myeloid-derived suppressor
cells (MDSC) represent one mechanism by which tumors induce ...T-cell suppression. Several factors pivotal to the accumulation
of MDSC are targeted by the tyrosine kinase inhibitor, sunitinib. The effect of sunitinib on MDSC-mediated immunosuppression
in RCC patients has been investigated.
Experimental Design: Patient peripheral blood levels of MDSC and regulatory T-cell (Treg) and T-cell production of IFN-γ were evaluated before
and after sunitinib treatment. Correlations between MDSC and Treg normalization as well as T-cell production of IFN-γ were
examined. The in vitro effect of sunitinib on patient MDSC was evaluated.
Results: Metastatic RCC patients had elevated levels of CD33 + HLA-DR â and CD15 + CD14 â MDSC, and these were partially overlapping populations. Treatment with sunitinib resulted in significant reduction in MDSC
measured by several criteria. Sunitinib-mediated reduction in MDSC was correlated with reversal of type 1 T-cell suppression,
an effect that could be reproduced by the depletion of MDSC in vitro . MDSC reduction in response to sunitinib correlated with a reversal of CD3 + CD4 + CD25 hi Foxp3 + Treg cell elevation. No correlation existed between a change in tumor burden and a change in MDSC, Treg, or T-cell production
of IFN-γ. In vitro addition of sunitinib reduced MDSC viability and suppressive effect when used at â¥1.0 μg/mL. Sunitinib did not induce MDSC
maturation in vitro .
Conclusions: Sunitinib-based therapy has the potential to modulate antitumor immunity by reversing MDSC-mediated tumor-induced immunosuppression.
Purpose: Immune dysfunction is well documented in renal cell carcinoma (RCC) patients and likely contributes to tumor evasion. This
dysfunction includes a shift from a type-1 to a type-2 T-cell ...cytokine response and enhanced T-regulatory (Treg) cell expression.
Given the antitumor activity of select tyrosine kinase inhibitors such as sunitinib in metastatic RCC (mRCC) patients, it
is relevant to assess their effect on the immune system.
Experimental Design: Type-1 (IFNγ) and type-2 (interleukin-4) responses were assessed in T cells at baseline and day 28 of treatment with sunitinib
(50 mg/d) by measuring intracellular cytokines after in vitro stimulation with anti-CD3/anti-CD28 antibodies.
Results: After one cycle of treatment, there was a significant increase in the percentage of IFNγ-producing T cells (CD3 + , P < 0.001; CD3 + CD4 + , P = 0.001), a reduction in interleukin-4 production (CD3 + cells, P = 0.05), and a diminished type-2 bias ( P = 0.005). The increase in type-1 response may be partly related to modulation of Treg cells. The increased percentage of
Treg cells noted in mRCC patients over healthy donors ( P = 0.001) was reduced after treatment, although not reaching statistical significance. There was, however, an inverse correlation
between the increase in type-1 response after two cycles of treatment and a decrease in the percentage of Treg cells ( r = −0.64, P = 0.01). In vitro studies suggest that the effects of sunitinib on Treg cells are indirect.
Conclusions: The demonstration that sunitinib improved type-1 T-cell cytokine response in mRCC patients while reducing Treg function provides
a basis for the rational combination of sunitinib and immunotherapy in mRCC.
The antiangiogenic drug sunitinib is a receptor tyrosine kinase inhibitor with significant, yet not curative, therapeutic effects in metastatic renal cell carcinoma (RCC). Sunitinib is also an ...immunomodulator, potently reversing myeloid-derived suppressor cell (MDSC) accumulation and T-cell inhibition in the blood even of nonresponder RCC patients. We observed that sunitinib similarly prevented MDSC accumulation and restored normal T-cell function to the spleens of tumor-bearing mice, independent of the capacity of sunitinib to inhibit tumor progression (RENCA>CT26>4T1). Both monocytic and neutrophilic splenic MDSC were highly repressible by sunitinib. In contrast, MDSC within the microenvironment of 4T1 tumors or human RCC tumors proved highly resistant to sunitinib and ambient T-cell function remained suppressed. Proteomic analyses comparing tumor to peripheral compartments showed that granulocyte macrophage colony-stimulating factor (GM-CSF) predicted sunitinib resistance and recombinant GM-CSF conferred sunitinib resistance to MDSC in vivo and in vitro. MDSC conditioning with GM-CSF uniquely inhibited signal transducers and activators of transcription (STAT3) and promoted STAT5 activation. STAT5ab(null/null) MDSC were rendered sensitive to sunitinib in the presence of GM-CSF in vitro. We conclude that compartment-dependent GM-CSF exposure in resistant tumors may account for the regionalized effect of sunitinib upon host MDSC modulation and hypothesize that ancillary strategies to decrease such regionalized escape will enhance the potency of sunitinib as an immunomodulator and a cancer therapy.
Abstract Myeloid-derived suppressor cells (MDSCs) are a heterogeneous, immature myeloid cell population with the ability to suppress innate and adaptive immune responses that promote tumor growth. ...MDSCs are increased in patients with multiple myeloma (MM) and have bidirectional interaction with tumors within the MM microenvironment. MM-MDSCs promote MM tumor growth and induce immune suppression; conversely, MM cells induce MDSC development and survival. Although the role of MDSCs in infections, inflammatory diseases and solid tumors has been extensively characterized, their tumor-promoting and immune-suppressive role in MM and the MM microenvironment is only beginning to emerge. The presence and activation of MDSCs in MM patients has been well documented; however, the direct actions and functional consequences of MDSCs on cancer cells is poorly defined. Immunosuppressive MDSCs play an important role in tumor progression primarily because of their capability to promote immune-escape, angiogenesis, drug resistance and metastasis. However, their role in the bone marrow (BM), the primary MM site, is poorly understood. MM remains an incurable malignancy, and it is likely that the BM microenvironment protects MM against chemotherapy agents and the host immune system. A growing body of evidence suggests that host immune cells with a suppressive phenotype contribute to a myeloma immunosuppressive network. Among the known suppressor cells, MDSCs and T regulatory cells (Tregs) have been found to be significantly increased in myeloma patients and their levels correlate with disease stage and clinical outcome. Furthermore, it has been shown that MDSC can mediate suppression of myeloma-specific T-cell responses through the induction of T-cell anergy and Treg development in the MM microenvironment. Here, we review clinical correlations and the preclinical proof-of-principle data on the role of MDSCs in myeloma immunotolerance and highlight the mechanistically relevant MDSC-targeted compounds and their potential utility in a new approach for anti-myeloma therapy.
Myeloid derived suppressor cells (MDSCs) are bone marrow derived cells with immunosuppressive properties. We have shown previously that MDSCs numbers are elevated in the circulation of GBM patients ...and that they produce reversible T cell dysfunction. Here, we evaluated whether MDSCs infiltrate human GBM tissues, and whether a commonly used mouse model of GBM reproduces the biology of MDSCs that is observed in patients. We evaluated tumor specimens from patients with newly diagnosed GBM. We harvested and evaluated normal brain, tumors and hematopoietic tissues from control, vehicle and sunitinib-treated mice. In human GBM tumors, MDSCs represented 5.4 ± 1.8 % of total cells. The majority of MDSCs (CD33+HLADR−) were lineage negative (CD14−CD15−), followed by granulocytic (CD15+CD14−) and monocytic (CD15−CD14+) subtypes. In murine GBM tumors, MDSCs were 8.06 ± 0.78 % of total cells, of which more were monocytic (M-MDSC, CD11b+ Gr1-low) than granulocytic (G-MDSC, CD11b+ Gr1-high). Treatment with the tyrosine kinase inhibitor sunitinib decreased the infiltration of both granulocytic and monocytic MDSCs in murine GBM tumors. In the hematopoietic tissues, circulating G-MDSC blood levels were reduced after sunitinib treatment. In tumors, both CD3
+
and CD4
+
T cell counts increased following sunitinib treatment (p ≤ 0.001). Total T cell proliferation (p < 0.001) and interferon gamma production (p = 0.004) were increased in the spleens of sunitinib treated mice. Sunitinib-treated mice survived longer than vehicle-treated mice (p = 0.002). MDSCs are present in both human and mouse GBM tumors. Sunitinib may have an immunostimulatory effect, as its use is associated with a reduction in G-MDSCs and improvement in anti-tumor immune function.
Previously we demonstrated that human glioblastoma cell lines induce apoptosis in peripheral blood T cells through partial involvement of secreted gangliosides. Here we show that GBM-derived ...gangliosides induce apoptosis through involvement of the TNF receptor and activation of the caspase cascade. Culturing T lymphocytes with GBM cell line derived gangliosides (10-20 μg/ml) demonstrated increased ROS production as early as 18 hrs as indicated by increased uptake of the dye H2DCFDA while western blotting demonstrated mitochondrial damage as evident by cleavage of Bid to t-Bid and by the release of cytochrome-c into the cytosol. Within 48-72 hrs apoptosis was evident by nuclear blebbing, trypan blue positivity and annexinV/7AAD staining. GBM-ganglioside induced activation of the effector caspase-3 along with both initiator caspases (-9 and -8) in T cells while both the caspase-8 and -9 inhibitors were equally effective in blocking apoptosis (60% protection) confirming the role of caspases in the apoptotic process. Ganglioside-induced T cell apoptosis did not involve production of TNF-α since anti-human TNFα antibody was unable to protect T cells from nuclear blebbing and subsequent cell death. However, confocal microscopy demonstrated co-localization of GM2 ganglioside with the TNF receptor and co-immunoprecipitation experiments showed recruitment of death domains FADD and TRADD with the TNF receptor post ganglioside treatment, suggesting direct interaction of gangliosides with the TNF receptor. Further confirmation of the interaction between GM2 and TNFR1 was obtained from confocal microscopy data with wild type and TNFR1 KO (TALEN mediated) Jurkat cells, which clearly demonstrated co-localization of GM2 and TNFR1 in the wild type cells but not in the TNFR1 KO clones. Thus, GBM-ganglioside can mediate T cell apoptosis by interacting with the TNF receptor followed by activation of both the extrinsic and the intrinsic pathway of caspases.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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