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1.
Oncoimmunology ; 7(12): e1474318, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30524884

RESUMO

Rationale: Regulatory T cells (Treg) play a pivotal role in the immunosuppressive tumor micro-environment in cancer, including mesothelioma. Recently, the combination of autologous tumor lysate-pulsed dendritic cells (DC) and metronomic cyclophosphamide (mCTX) was reported as a feasible and well-tolerated treatment in malignant pleural mesothelioma patients and further as a method to reduce circulating Tregs. Objectives: The aim of this study was to establish the immunological effects of mCTX alone and in combination with DC-based immunotherapy on circulating Treg and other T cell subsets in mesothelioma patients. Methods: Ten patients received mCTX and DC-based immunotherapy after chemotherapy (n = 5) or chemotherapy and debulking surgery (n = 5). Peripheral blood mononuclear cells before, during and after treatment were analyzed for various Treg and other lymphocyte subsets by flow cytometry. Results: After one week treatment with mCTX, both activated FoxP3hi and naïve CD45RA+ Tregs were effectively decreased in all patients. In addition, a shift from naïve and central memory towards effector memory and effector T cells was observed. Survival analysis showed that overall Treg levels before treatment were not correlated with survival, however, nTreg levels before treatment were positively correlated with survival. After completion of mCTX and DC-based immunotherapy treatment, all cell subsets returned to baseline levels, except for the proportions of proliferating EM CD8 T cells, which increased. Conclusions: mCTX treatment effectively reduced the proportions of circulating Tregs, both aTregs and nTregs, thereby favoring EM T cell subsets in mesothelioma patients. Interestingly, baseline levels of nTregs were positively correlated to overall survival upon complete treatment.

2.
Clin Cancer Res ; 24(4): 766-776, 2018 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-29233904

RESUMO

Purpose: Mesothelioma has been regarded as a nonimmunogenic tumor, which is also shown by the low response rates to treatments targeting the PD-1/PD-L1 axis. Previously, we demonstrated that autologous tumor lysate-pulsed dendritic cell (DC) immunotherapy increased T-cell response toward malignant mesothelioma. However, the use of autologous tumor material hampers implementation in large clinical trials, which might be overcome by using allogeneic tumor cell lines as tumor antigen source. The purpose of this study was to investigate whether allogeneic lysate-pulsed DC immunotherapy is effective in mice and safe in humans.Experimental Design: First, in two murine mesothelioma models, mice were treated with autologous DCs pulsed with either autologous or allogeneic tumor lysate or injected with PBS (negative control). Survival and tumor-directed T-cell responses of these mice were monitored. Results were taken forward in a first-in-human clinical trial, in which 9 patients were treated with 10, 25, or 50 million DCs per vaccination. DC vaccination consisted of autologous monocyte-derived DCs pulsed with tumor lysate from five mesothelioma cell lines.Results: In mice, allogeneic lysate-pulsed DC immunotherapy induced tumor-specific T cells and led to an increased survival, to a similar extent as DC immunotherapy with autologous tumor lysate. In the first-in-human clinical trial, no dose-limiting toxicities were established and radiographic responses were observed. Median PFS was 8.8 months [95% confidence interval (CI), 4.1-20.3] and median OS not reached (median follow-up = 22.8 months).Conclusions: DC immunotherapy with allogeneic tumor lysate is effective in mice and safe and feasible in humans. Clin Cancer Res; 24(4); 766-76. ©2017 AACR.


Assuntos
Células Alógenas/imunologia , Vacinas Anticâncer/imunologia , Células Dendríticas/imunologia , Imunoterapia/métodos , Neoplasias Pulmonares/terapia , Mesotelioma/terapia , Idoso , Animais , Autoenxertos , Vacinas Anticâncer/administração & dosagem , Extratos Celulares/imunologia , Linhagem Celular Tumoral , Células Cultivadas , Feminino , Humanos , Neoplasias Pulmonares/imunologia , Masculino , Mesotelioma/imunologia , Mesotelioma Maligno , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos CBA , Pessoa de Meia-Idade , Análise de Sobrevida
3.
Cancer Immunol Res ; 5(7): 535-546, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28536100

RESUMO

New immunotherapeutic strategies are needed to induce effective antitumor immunity in all cancer patients. Malignant mesothelioma is characterized by a poor prognosis and resistance to conventional therapies. Infiltration of tumor-associated macrophages (TAM) is prominent in mesothelioma and is linked to immune suppression, angiogenesis, and tumor aggressiveness. Therefore, TAM depletion could potentially reactivate antitumor immunity. We show that M-CSFR inhibition using the CSF-1R kinase inhibitor PLX3397 (pexidartinib) effectively reduced numbers of TAMs, circulating nonclassical monocytes, as well as amount of neoangiogenesis and ascites in mesothelioma mouse models, but did not improve survival. When combined with dendritic cell vaccination, survival was synergistically enhanced with a concomitant decrease in TAMs and an increase in CD8+ T-cell numbers and functionality. Total as well as tumor antigen-specific CD8+ T cells in tumor tissue of mice treated with combination therapy showed reduced surface expression of the programmed cell death protein-1 (PD-1), a phenomenon associated with T-cell exhaustion. Finally, mice treated with combination therapy were protected from tumor rechallenge and displayed superior T-cell memory responses. We report that decreasing local TAM-mediated immune suppression without immune activation does not improve survival. However, combination of TAM-mediated immune suppression with dendritic cell immunotherapy generates robust and durable antitumor immunity. These findings provide insights into the interaction between immunotherapy-induced antitumor T cells and TAMs and offer a therapeutic strategy for mesothelioma treatment. Cancer Immunol Res; 5(7); 535-46. ©2017 AACR.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Células Dendríticas/imunologia , Imunoterapia Adotiva , Neoplasias Pulmonares/imunologia , Mesotelioma/imunologia , Receptor de Fator Estimulador de Colônias de Macrófagos/imunologia , Aminopiridinas/administração & dosagem , Animais , Antígenos de Neoplasias/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linhagem Celular Tumoral , Modelos Animais de Doenças , Humanos , Neoplasias Pulmonares/induzido quimicamente , Neoplasias Pulmonares/terapia , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Mesotelioma/induzido quimicamente , Mesotelioma/terapia , Mesotelioma Maligno , Invasividade Neoplásica/imunologia , Receptor de Morte Celular Programada 1/imunologia , Inibidores de Proteínas Quinases/administração & dosagem , Pirróis/administração & dosagem
5.
Lung Cancer ; 107: 36-40, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-27168021

RESUMO

OBJECTIVES: Clinical studies have proven the potential of immunotherapy in malignancies. To increase efficacy, a prerequisite is that treatment is tailored, so precision immune-oncology is the logical next step. In order to tailor treatment, characterization of the patient's tumor environment is key. Pleural effusion (PE) often accompanies malignant pleural mesothelioma (MPM) and is an important part of the MPM environment. Furthermore, the composition of PE is used as surrogate for the tumor. In this study, we provide an insight in the dynamics of the MPM environment through characterization of PE composition over time and show that the immunological characteristics of PE do not necessarily mirror those of the tumor. MATERIALS AND METHODS: From 5 MPM patients, PE and tumor biopsies were acquired at the same time point. From one of these patients multiple PEs were obtained. PEs were acquired performing thoracocenteses and total cell amounts were determined. Immunohistochemistry was performed to quantify immune cell composition (T cells, macrophages) and tumor cells in PE derived cytospins and tumor biopsies. RESULTS: The PE amount and (immune) cellular composition varied considerably over time between multiple (n=10) thoracocenteses. These dynamics could in part be attributed to the treatment regimen consisting of standard chemotherapy and dendritic cell (DC)-based immunotherapy. In addition, the presence of T cells and macrophages in PE did not necessarily mirror the infiltration of these immune cells within tumor biopsies in 4 out of 5 patients. CONCLUSIONS: In this proof-of-concept study with limited sample size, we demonstrate that the composition of PE is dynamic and influenced by treatment. Furthermore, the immune cell composition of PE does not automatically reflect the properties of tumor tissue. This has major consequences when applying precision immunotherapy based on PE findings in patients. Furthermore, it implies a regulated trafficking of immune regulating cells within the tumor environment.


Assuntos
Imunoterapia/métodos , Neoplasias Pulmonares/patologia , Mesotelioma/patologia , Derrame Pleural Maligno/imunologia , Neoplasias Pleurais/imunologia , Humanos , Neoplasias Pulmonares/complicações , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/imunologia , Macrófagos/metabolismo , Mesotelioma/complicações , Mesotelioma/tratamento farmacológico , Mesotelioma/imunologia , Mesotelioma Maligno , Derrame Pleural Maligno/patologia , Derrame Pleural Maligno/terapia , Neoplasias Pleurais/tratamento farmacológico , Neoplasias Pleurais/patologia , Neoplasias Pleurais/terapia , Medicina de Precisão , Linfócitos T/imunologia , Toracentese/métodos , Microambiente Tumoral/imunologia
6.
J Thorac Oncol ; 11(10): 1755-64, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27418106

RESUMO

INTRODUCTION: Clinical studies have demonstrated beneficial effects of immunotherapy in malignant pleural mesothelioma. The pleural cavity seems an attractive compartment to administer these types of therapies; however, local immunosuppressive mechanisms could hamper their efficacy. Macrophages are abundantly present within the mesothelioma microenvironment. This study investigates the influence of the macrophage phenotype, macrophages' capacity to inhibit local immune responses, and the decisive role of pleural effusion (PE) in this regard. METHODS: We cultured macrophages in the presence of PEs and investigated their phenotype. Macrophages and T cells were cocultured in the presence of PEs and tumor cell line supernatants. The levels of 11 cytokines and the prostanoid prostaglandin E2 were measured in PEs and supernatants. The presence and phenotype of macrophages and T cell subsets was measured in the PE of patients with mesothelioma. RESULTS: PE induced a tumor-promoting M2 phenotype in macrophages, which was confirmed by the suppressive activity of macrophages on T cell proliferation during coculture. Prostanoid prostaglandin E2 was identified as a potential inducer of the suppressive capacity of macrophages in PE. Macrophages isolated from PEs displayed an M2 phenotype and were negatively correlated with T cells in vivo. CONCLUSIONS: The current study demonstrates that macrophages in PE can play a pivotal role in directly hampering the antitumor T cell immune response. This emphasizes the potential of macrophages as a therapeutic target in mesothelioma and indicates that the presence and phenotype of macrophages in PE should be taken into consideration in the application of (intrapleural) immunotherapies.


Assuntos
Neoplasias Pulmonares/complicações , Macrófagos/metabolismo , Mesotelioma/complicações , Derrame Pleural/etiologia , Linfócitos T/patologia , Idoso , Linhagem Celular Tumoral , Feminino , Humanos , Neoplasias Pulmonares/patologia , Masculino , Mesotelioma/patologia , Mesotelioma Maligno , Derrame Pleural/patologia , Microambiente Tumoral
7.
J Clin Oncol ; 34(26): 3204-12, 2016 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-27432922

RESUMO

PURPOSE: Programmed cell death protein-1- checkpoint blockers have recently been approved as second-line treatment for advanced non-small-cell lung cancer (NSCLC). Unfortunately, only a subgroup of patients responds and shows long-term survival to these therapies. Tumor vaccines and cellular immunotherapies could synergize with checkpoint blockade, but which of these treatments is most efficacious is unknown. In this meta-analysis, we assessed the efficacy of tumor vaccination and cellular immunotherapy in NSCLC. METHODS: We searched for randomized controlled trials (RCTs) investigating cellular immunotherapy or vaccines in NSCLC. We used random effects models to analyze overall survival (OS) and progression-free survival (PFS), expressed as hazard ratios (HRs), and differences in time (months). The effect of immunotherapy type, disease stage, tumor histology, and concurrent chemotherapy was assessed using subgroup analysis and meta-regression. All procedures were performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. RESULTS: We identified 18 RCTs that matched our selection criteria; these included a total of 6,756 patients. Immunotherapy extended NSCLC survival and PFS, expressed as HR (OS: HR, 0.81, 95% CI, 0.70 to 0.94, P = .01; PFS: HR, 0.83, 95% CI, 0.72 to 0.95, P = .006) and month difference (OS: difference, 5.43 months, 95% CI, 3.20 to 7.65, P < .005; PFS: difference, 3.24 months, 95% CI, 1.61 to 4.88, P < .005). Cellular therapies outperformed tumor vaccines (OS as HR: P = .005, month difference: P < .001; PFS as HR: P = .001, month difference: P = .004). There was a benefit of immunotherapy in low-stage compared with high-stage NSCLC and with concurrent administration of chemotherapy only in one of four outcome measures evaluated (PFS in months: P = .01 and PFS as HR: P = .031, respectively). There was no significant effect of tumor histology on survival or PFS. CONCLUSION: Tumor vaccines and cellular immunotherapies enhanced OS and PFS in NSCLC. Cellular immunotherapy was found to be more effective than tumor vaccination. These findings have implications for future studies investigating combination immunotherapy in NSCLC.


Assuntos
Vacinas Anticâncer/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/terapia , Imunoterapia Adotiva , Neoplasias Pulmonares/terapia , Vacinas Anticâncer/efeitos adversos , Carcinoma Pulmonar de Células não Pequenas/imunologia , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/patologia , Intervalo Livre de Doença , Humanos , Imunoterapia Adotiva/efeitos adversos , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Estadiamento de Neoplasias , Fatores de Risco , Análise de Sobrevida , Fatores de Tempo , Resultado do Tratamento
8.
Am J Respir Crit Care Med ; 193(9): 1023-31, 2016 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-26652184

RESUMO

RATIONALE: We demonstrated previously that autologous tumor lysate-pulsed dendritic cell-based immunotherapy in patients with malignant pleural mesothelioma is feasible, well-tolerated, and capable of inducing immunologic responses against tumor cells. In our murine model, we found that reduction of regulatory T cells with metronomic cyclophosphamide increased the efficacy of immunotherapy. OBJECTIVES: To assess the decrease in number of peripheral blood regulatory T cells during combination therapy of low-dose cyclophosphamide and dendritic cell immunotherapy and determine the induction of immunologic responses with this treatment in patients with mesothelioma. METHODS: Ten patients with malignant pleural mesothelioma received metronomic cyclophosphamide and dendritic cell-based immunotherapy. During the treatment, peripheral blood mononuclear cells were analyzed for regulatory T cells and immunologic responses. MEASUREMENTS AND MAIN RESULTS: Administration of dendritic cells pulsed with autologous tumor lysate combined with cyclophosphamide in patients with mesothelioma was safe, the only side effect being moderate fever. Dendritic cell vaccination combined with cyclophosphamide resulted in radiographic disease control in 8 of the 10 patients. Overall survival was promising, with 7 out of 10 patients having a survival of greater than or equal to 24 months and two patients still alive after 50 and 66 months. Low-dose cyclophosphamide reduced the percentage of regulatory T cells of total CD4 cells in peripheral blood from 9.43 (range, 4.34-26.10) to 4.51 (range, 0.27-10.30) after 7 days of cyclophosphamide treatment (P = 0.02). CONCLUSIONS: Consolidation therapy with autologous tumor lysate-pulsed dendritic cell-based therapy and simultaneously reducing the tumor-induced immune suppression is well-tolerated and shows signs of clinical activity in patients with mesothelioma. Clinical trial registered with www.clinicaltrials.gov (NCT 01241682).


Assuntos
Ciclofosfamida/uso terapêutico , Células Dendríticas/imunologia , Neoplasias Pulmonares/tratamento farmacológico , Mesotelioma/tratamento farmacológico , Vacinação/métodos , Adjuvantes Farmacêuticos/uso terapêutico , Adulto , Idoso , Terapia Combinada/métodos , Ciclofosfamida/imunologia , Feminino , Humanos , Imunossupressores/imunologia , Imunossupressores/uso terapêutico , Imunoterapia/métodos , Neoplasias Pulmonares/imunologia , Masculino , Mesotelioma/imunologia , Mesotelioma Maligno , Pessoa de Meia-Idade , Pleura , Linfócitos T Reguladores/imunologia , Resultado do Tratamento
9.
Lung Cancer ; 88(3): 332-7, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25843042

RESUMO

OBJECTIVES: In patients with malignant pleural mesothelioma (MPM), local tumor outgrowth (LTO) after invasive procedures is a well-known complication. Currently, no biomarker is available to predict the occurrence of LTO. This study aims to investigate whether the tumor macrophage infiltration and phenotype of and/or the infiltration of CD8+ T-cells predicts LTO. MATERIALS AND METHODS: Ten mesothelioma patients who developed LTO were clinically and pathologically matched with 10 non-LTO mesothelioma patients. Immunohistochemistry was performed on diagnostic biopsies to determine the total TAM (CD68), the M2 TAM (CD163) and CD8+ T-cell count (CD8). RESULTS: The mean M2/total TAM ratio differed between the two groups: 0.90±0.09 in the LTO group versus 0.63±0.09 in patients without LTO (p<0.001). In addition, the mean CD8+ T-cell count was significantly different between the two groups: 30 per 0.025 cm2 (range 2-60) in the LTO group and 140 per 0.025 cm2 (range 23-314) in the patients without LTO (p<0.01). CONCLUSION: This study shows that patients who develop LTO after a local intervention have a higher M2/total TAM ratio and lower CD8+ cell count at diagnosis compared to patients who did not develop this outgrowth. We propose that the M2/total TAM ratio and the CD8+ T-cell amount are potential tools to predict which MPM patients are prone to develop LTO.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/patologia , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/patologia , Macrófagos/imunologia , Macrófagos/patologia , Mesotelioma/imunologia , Mesotelioma/patologia , Neoplasias Pleurais/imunologia , Neoplasias Pleurais/patologia , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores , Contagem de Células , Feminino , Humanos , Imuno-Histoquímica , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/mortalidade , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/patologia , Macrófagos/metabolismo , Masculino , Mesotelioma/tratamento farmacológico , Mesotelioma/mortalidade , Mesotelioma Maligno , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Fenótipo , Neoplasias Pleurais/tratamento farmacológico , Neoplasias Pleurais/mortalidade , Prognóstico , Tomografia Computadorizada por Raios X , Resultado do Tratamento
10.
PLoS One ; 9(9): e106742, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25192022

RESUMO

HYPOTHESIS: The tumor micro-environment and especially the different macrophage phenotypes appear to be of great influence on the behavior of multiple tumor types. M1 skewed macrophages possess anti-tumoral capacities, while the M2 polarized macrophages have pro-tumoral capacities. We analyzed if the macrophage count and the M2 to total macrophage ratio is a discriminative marker for outcome after surgery in malignant pleural mesothelioma (MPM) and studied the prognostic value of these immunological cells. METHODS: 8 MPM patients who received induction chemotherapy and surgical treatment were matched on age, sex, tumor histology, TNM stage and EORTC score with 8 patients who received chemotherapy only. CD8 positive T-cells and the total macrophage count, using the CD68 pan-macrophage marker, and CD163 positive M2 macrophage count were determined in tumor specimens prior to treatment. RESULTS: The number of CD68 and CD163 cells was comparable between the surgery and the non-surgery group, and was not related to overall survival (OS) in both the surgery and non-surgery group. However, the CD163/CD68 ratio did correlate with OS in both in the total patient group (Pearson r -0.72, p<0.05). No correlation between the number of CD8 cells and prognosis was found. CONCLUSIONS: The total number of macrophages in tumor tissue did not correlate with OS in both groups, however, the CD163/CD68 ratio correlates with OS in the total patient group. Our data revealed that the CD163/CD68 ratio is a potential prognostic marker in epithelioid mesothelioma patients independent of treatment but cannot be used as a predictive marker for outcome after surgery.


Assuntos
Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Macrófagos/metabolismo , Mesotelioma/metabolismo , Mesotelioma/patologia , Fenótipo , Neoplasias Pleurais/metabolismo , Neoplasias Pleurais/patologia , Adulto , Idoso , Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/metabolismo , Antígenos de Superfície/metabolismo , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/patologia , Feminino , Humanos , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/mortalidade , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Linfócitos do Interstício Tumoral/patologia , Macrófagos/imunologia , Macrófagos/patologia , Masculino , Mesotelioma/imunologia , Mesotelioma/mortalidade , Mesotelioma Maligno , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Pleurais/imunologia , Neoplasias Pleurais/mortalidade , Prognóstico , Receptores de Superfície Celular/metabolismo , Microambiente Tumoral
11.
Curr Opin Pharmacol ; 17: 17-21, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25011112

RESUMO

We have to strengthen our 'chess-playing skills' when using immunotherapeutic approaches in cancer treatment: know the cancerous opponent, study its evolution and have an eye for its weaknesses. Besides tumor cells, other pieces on the board are stromal cells, endothelial cells and different immune cells. Some of these immune cells, like helper and cytotoxic T cells, natural killer (T) cells and mature dendritic cells are of help, others like regulatory T cells and myeloid-derived suppressor cells belong to the opponent, while macrophages and neutrophils can belong to both. A personalized approach, by selecting the optimal treatment from the myriad of possibilities based on biomarker findings, is essential to attack that particular cancer at that moment. We have to adapt the strategy to the changing positions created by the opponent. Using all these skills, we might control cancer growth in the future.


Assuntos
Vacinas Anticâncer/uso terapêutico , Fatores Imunológicos/uso terapêutico , Imunoterapia/métodos , Linfócitos do Interstício Tumoral/efeitos dos fármacos , Neoplasias/terapia , Evasão Tumoral/efeitos dos fármacos , Animais , Biomarcadores Tumorais/metabolismo , Desenho de Fármacos , Humanos , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Terapia de Alvo Molecular , Neoplasias/imunologia , Neoplasias/metabolismo , Neoplasias/patologia , Transdução de Sinais/efeitos dos fármacos , Microambiente Tumoral
13.
Transl Lung Cancer Res ; 3(1): 34-45, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25806279

RESUMO

A very recent finding is the role of immune activation in cancer. The assumption that stimulating the patient's immune system to attack tumors is a valuable treatment option in malignant diseases has gained more acceptance. However the high immunosuppressive effects caused by the tumor limits this beneficial effect. There is a delicate balance between immunoactivation and immunosuppression in a patient. Especially in non small cell lung cancer (NSCLC), the role of immunosuppressive cells hampering immune activation is high. But also in small cell lung cancer (SCLC) and mesothelioma immunosuppressive activity is high. This is suggested to be related to the type of tumor, advanced stage of the disease, and the tumor load. In this review, we provide an overview of the progress and challenges in the immunotherapeutic approaches in lung cancer. We conclude with the concept that immunotherapy in thoracic malignancies must be tailored made to the balance of the immune system.

14.
Artigo em Inglês | MEDLINE | ID: mdl-24223258

RESUMO

BACKGROUND: In 2001, it was postulated that tumour-derived exosomes could be a potent source of tumour-associated antigens (TAA). Since then, much knowledge is gained on their role in tumorigenesis but only very recently tumour-derived exosomes were used in dendritic cell (DC)-based immunotherapy. For this, DCs were cultured ex-vivo and loaded with exosomes derived from immunogenic tumours such as melanoma or glioma and re-administrated to induce anti-tumour responses in primary and metastatic tumour mouse models. In contrast, malignant mesothelioma (MM) is a non-immunogenic tumour and because only a few mesothelioma-specific TAA are known to date, we investigated whether mesothelioma-derived exosomes could be used as antigen source in DC-based immunotherapy. METHODS: Mouse MM AB1 cells were used to generate tumour lysate and tumour-derived exosomes. Tumour lysate was generated by 5 cycles of freeze-thawing followed by sonication of AB1 cells. Tumour exosomes were collected from the AB1 cell culture supernatant and followed a stepwise ultracentrifugation. Protein quantification and electron microscopy were performed to determine the protein amount and to characterise their morphology. To test whether MM derived exosomes are immunogenic and able to stimulate an anti-tumoral response, BALB/c mice were injected with a lethal dose of AB1 tumour cells at day 0, followed by intraperitoneal injection of a single dose of DCs loaded with tumour exosomes, DCs loaded with tumour lysate, or phosphate buffered saline (PBS), at day 7. RESULTS: Mice which received tumour exosome-loaded DC immunotherapy had an increased median and overall survival compared to mice which received tumour lysate-loaded DC or PBS. CONCLUSION: In this study, we showed that DC immunotherapy loaded with tumour exosomes derived from non-immunogenic tumours improved survival of tumour bearing mice.

15.
Lung Cancer ; 81(3): 468-474, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23850196

RESUMO

Myeloid-derived suppressor cells (MDSC) are a heterogeneous population of immature and progenitor myeloid cells with immunosuppressive activity that are increased in cancer patients. Until now, the characterization of MDSC in humans was very challenging. The aim of this study was to determine the characterization and optimal assessment of MDSC and to investigate their presence and function in blood of advanced-stage NSCLC patients. We determined MDSC and lymphocyte populations in peripheral blood mononuclear cells (PBMC) samples of 185 treatment-naïve NSCLC patients and 20 healthy controls (HC). NSCLC patients had an increased population of PMN-MDSC compared to HC (p < 0.0001). Frequencies of CD4(+) and CD8(+) T-cells were significantly decreased in NSCLC patients (p < 0.0001 and p = 0.05). We found that PMN-MDSC were able to suppress T-cell proliferation in vitro. qRT-PCR showed that arginase-1 (Arg-1) mRNA is mainly expressed by MDSC and that the level of Arg-1 in PBMC correlates with the frequency of MDSC in PBMC (Spearman's rho: 0.797). There were significant differences in MDSC and lymphocyte populations between NSCLC patients and HC. We found that MDSC frequencies are stable up to six hours at room temperature after blood was drawn and that cryopreservation leads to a strong decrease of MDSC in PBMC. We show that Arg-1 mRNA expression is a valuable method to determine the levels of MDSC in peripheral blood of cancer patients. This method is therefore a useful alternative for the complex flowcytometric analysis in large multicenter patient studies.


Assuntos
Arginase/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/imunologia , Expressão Gênica , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/imunologia , Células Mieloides/imunologia , Idoso , Carcinoma Pulmonar de Células não Pequenas/patologia , Criopreservação , Feminino , Humanos , Imunofenotipagem , Contagem de Leucócitos , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Neoplasias Pulmonares/patologia , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Células Mieloides/metabolismo , Estadiamento de Neoplasias , Fenótipo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo
16.
Cancer Res ; 73(8): 2381-8, 2013 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-23580578

RESUMO

There is growing evidence that activation of the immune system may be an effective treatment for patients with either small cell lung cancer or non-small cell lung cancer (NSCLC). Immunomodulatory antibodies directed against cytotoxic T cell-associated antigen 4 (CTLA-4/CD152) and programmed cell death ligand 1 (PDL1/CD274) showed clinical efficacy in patients with lung cancer. The key immune cells responsible for antitumor activity are the CTLs. The presence of these tumor-directed CTLs, both in number and functionality, is a prerequisite for the immune system to attack cancer cells. Immunomodulatory agents attempt to increase the efficacy of CTL activity. Thus, the limited number of patients who benefit from immunomodulatory antibodies may be caused by either an inadequate number or the impairment of CTL activity by the hostile environment created by the tumor. In this review, we discuss tumor-induced impairment of CTLs and experimental treatments that can stimulate T-cell responses and optimize specific CTL function. We discuss 2 types of immune cells with known suppressive capacity on CTLs that are of pivotal importance in patients with lung cancer: regulatory T cells and myeloid-derived suppressor cells.


Assuntos
Anticorpos/imunologia , Antígeno CTLA-4/imunologia , Imunomodulação , Neoplasias Pulmonares/imunologia , Linfócitos T Citotóxicos/imunologia , Animais , Anticorpos/uso terapêutico , Citotoxicidade Imunológica , Humanos , Imunoterapia , Neoplasias Pulmonares/terapia , Ativação Linfocitária
17.
BMC Pulm Med ; 12: 77, 2012 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-23234250

RESUMO

BACKGROUND: During the past decades, numerous efforts have been made to decrease the death rate among lung cancer patients. Nonetheless, the improvement in long-term survival has been limited and lung cancer is still a devastating disease. DISCUSSION: With this article we would like to point out that survival of lung cancer could be strongly improved by controlling two pivotal prognostic factors: stage and treatment. This is corresponding with recent reports that show a decrease in lung cancer mortality by screening programs. In addition, modulation of the patient's immune system by immunotherapy either as monotherapy or combined with conventional cancer treatments offers the prospect of tailoring treatments much more precisely and has also been shown to lead to a better response to treatment and overall survival of non-small cell lung cancer patients. SUMMARY: Since only small improvements in survival can be expected in advanced disease with the use of conventional therapies, more research should be focused on lung cancer screening programs and patient tailored immunotherapy with or without conventional therapies. If these approaches are clinically combined in a standard multidisciplinary policy we might be able to advance the survival of patients with lung cancer.


Assuntos
Detecção Precoce de Câncer/tendências , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/mortalidade , Tratamento Farmacológico , Humanos , Imunoterapia , Neoplasias Pulmonares/terapia , Estadiamento de Neoplasias , Prognóstico , Taxa de Sobrevida
18.
BMC Cancer ; 12: 580, 2012 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-23217146

RESUMO

Cancer research has devoted most of its energy over the past decades on unraveling the control mechanisms within tumor cells that govern its behavior. From this we know that the onset of cancer is the result of cumulative genetic mutations and epigenetic alterations in tumor cells leading to an unregulated cell cycle, unlimited replicative potential and the possibility for tissue invasion and metastasis. Until recently it was often thought that tumors are more or less undetected or tolerated by the patient's immune system causing the neoplastic cells to divide and spread without resistance. However, it is without any doubt that the tumor environment contains a wide variety of recruited host immune cells. These tumor infiltrating immune cells influence anti-tumor responses in opposing ways and emerges as a critical regulator of tumor growth. Here we provide a summary of the relevant immunological cell types and their complex and dynamic roles within an established tumor microenvironment. For this, we focus on both the systemic compartment as well as the local presence within the tumor microenvironment of late-stage non-small cell lung cancer (NSCLC), admitting that this multifaceted cellular composition will be different from earlier stages of the disease, between NSCLC patients. Understanding the paradoxical role that the immune system plays in cancer and increasing options for their modulation may alter the odds in favor of a more effective anti-tumor immune response. We predict that the future standard of care of lung cancer will involve patient-tailor-made combination therapies that associate (traditional) chemotherapeutic drugs and biologicals with immune modulating agents and in this way complement the therapeutic armamentarium for this disease.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/imunologia , Carcinoma Pulmonar de Células não Pequenas/terapia , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/terapia , Linfócitos do Interstício Tumoral/imunologia , Humanos , Imunoterapia/métodos , Imunoterapia/tendências , Medicina de Precisão/métodos , Medicina de Precisão/tendências , Microambiente Tumoral/imunologia
19.
Immunotherapy ; 4(10): 1011-22, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23148753

RESUMO

Mesothelioma is a rare thoracic malignancy with a dismal prognosis. Current treatment options are scarce and clinical outcomes are rather disappointing. Due to the immunogenic nature of mesothelioma, several studies have investigated immunotherapeutic strategies to improve the prognosis of patients with mesothelioma. In the last decade, progress in knowledge of the modulation of the immune system to attack the tumor has been remarkable, but the optimal strategy for immunotherapy has yet to be unraveled. Because of their potent antigen-presenting capacity, dendritic cells are acknowledged as a promising agent in immunotherapeutic approaches in a number of malignancies. This review gives an update and provides a future perspective in which immunotherapy may improve the outcome of mesothelioma therapy.


Assuntos
Células Dendríticas/imunologia , Células Dendríticas/transplante , Imunoterapia/métodos , Mesotelioma/imunologia , Mesotelioma/terapia , Animais , Humanos
20.
Lung Cancer ; 76(3): 452-6, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22226628

RESUMO

INTRODUCTION: It is well known that pulmonary tuberculosis is associated with an increased risk of lung cancer. We investigated whether a history of pulmonary tuberculosis is an independent risk factor for lung cancer survival in Caucasian patients. METHODS: The data of the prospective population-based cohort of The Rotterdam Study were used. During a mean follow-up time of 18 years, there were 214 incident cases of pathology-proven lung cancer in a source population of 7983 study participants. History of tuberculosis was assessed at baseline by interviewers using standardized questionnaires. Associations of lung cancer survival with the occurrence of pulmonary tuberculosis were assessed using Cox's proportional hazard regression analysis adjusted for age, gender, pack-years, educational level and tumor stage. RESULTS: A history of tuberculosis was reported in 13 of the 214 subjects with lung cancer. The survival of patients with lung cancer was significantly shorter in subjects with a history of pulmonary tuberculosis (HR=2.36, CI95%: 1.1-4.9), than in subjects without a history of pulmonary tuberculosis with a mean difference of 311 days. CONCLUSION: The presence of a history of pulmonary tuberculosis may be an important prognostic factor in the survival of lung cancer.


Assuntos
Neoplasias Pulmonares/complicações , Neoplasias Pulmonares/mortalidade , Tuberculose Pulmonar/complicações , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Seguimentos , Humanos , Neoplasias Pulmonares/epidemiologia , Masculino , Pessoa de Meia-Idade , Países Baixos/epidemiologia , Prognóstico , Estudos Prospectivos , Fatores de Risco , População Branca
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