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1.
Commun Biol ; 4(1): 914, 2021 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-34312483

RESUMO

Malignant pleural mesothelioma (MPM) is an aggressive neoplasm originating from the pleura. Non-epithelioid (biphasic and sarcomatoid) MPM are particularly resistant to therapy. We investigated the role of the GITR-GITRL pathway in mediating the resistance to therapy. We found that GITR and GITRL expressions were higher in the sarcomatoid cell line (CRL5946) than in non-sarcomatoid cell lines (CRL5915 and CRL5820), and that cisplatin and Cs-137 irradiation increased GITR and GITRL expressions on tumor cells. Transcriptome analysis demonstrated that the GITR-GITRL pathway was promoting tumor growth and inhibiting cell apoptosis. Furthermore, GITR+ and GITRL+ cells demonstrated increased spheroid formation in vitro and in vivo. Using patient derived xenografts (PDXs), we demonstrated that anti-GITR neutralizing antibodies attenuated tumor growth in sarcomatoid PDX mice. Tumor immunostaining demonstrated higher levels of GITR and GITRL expressions in non-epithelioid compared to epithelioid tumors. Among 73 patients uniformly treated with accelerated radiation therapy followed by surgery, the intensity of GITR expression after radiation negatively correlated with survival in non-epithelioid MPM patients. In conclusion, the GITR-GITRL pathway is an important mechanism of autocrine proliferation in sarcomatoid mesothelioma, associated with tumor stemness and resistance to therapy. Blocking the GITR-GITRL pathway could be a new therapeutic target for non-epithelioid mesothelioma.


Assuntos
Antineoplásicos/farmacologia , Radioisótopos de Césio/farmacologia , Cisplatino/farmacologia , Regulação Neoplásica da Expressão Gênica , Proteína Relacionada a TNFR Induzida por Glucocorticoide/genética , Mesotelioma Maligno/genética , Fatores de Necrose Tumoral/genética , Animais , Linhagem Celular Tumoral , Feminino , Proteína Relacionada a TNFR Induzida por Glucocorticoide/metabolismo , Humanos , Mesotelioma Maligno/terapia , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Fatores de Necrose Tumoral/metabolismo
2.
Sci Transl Med ; 13(589)2021 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-33853932

RESUMO

Malignant pleural mesothelioma (MPM) is an intractable disease with an extremely poor prognosis. Our clinical protocol for MPM of subablative radiotherapy (RT) followed by radical surgery achieved better survival compared to other multimodal treatments, but local relapse and metastasis remain a problem. This subablative RT elicits an antitumoral immune response that is limited by the immunosuppressive microenvironment generated by regulatory T (Treg) cells. The antitumor effect of immunotherapy to simultaneously modulate the immune activation and the immune suppression after subablative RT has not been investigated in MPM. Herein, we demonstrated a rationale to combine interleukin-15 (IL-15) superagonist (IL-15SA) and glucocorticoid-induced tumor necrosis factor receptor-related protein (GITR) agonist (DTA-1) with subablative RT in mesothelioma. IL-15SA boosted the systemic expansion of specific antitumoral memory CD8+ T cells that were induced by RT in mice. Their effect, however, was limited by the up-regulation and activation of Treg cells in the radiated tumor microenvironment. Hence, selective depletion of intratumoral Treg cells through DTA-1 enhanced the benefit of subablative RT in combination with IL-15SA. The addition of surgical resection of the radiated tumor in combination with IL-15SA and DTA-1 maximized the benefit of RT and was accompanied by a reproducible abscopal response in a concomitant tumor model. These data support the development of clinical trials in MPM to test such treatment options for patients with locally advanced or metastatic tumors.


Assuntos
Mesotelioma , Neoplasias Pleurais , Animais , Linfócitos T CD8-Positivos , Humanos , Imunidade , Mesotelioma/terapia , Camundongos , Recidiva Local de Neoplasia , Neoplasias Pleurais/terapia , Linfócitos T Reguladores , Microambiente Tumoral
3.
J Immunol ; 205(9): 2519-2531, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-32948683

RESUMO

Increasing evidence indicates that local hypofractionated radiotherapy (LRT) can elicit both immunogenic and immunosuppressive local and systemic immune responses. We thus hypothesized that blockade of LRT-induced immunosuppressive responses could augment the antitumor effects and induce an abscopal response. In this study, we found that the upregulation of Foxp3+ regulatory T cells (Tregs) in the mesothelioma tumor microenvironment after nonablative oligofractionated irradiation significantly limited the success of irradiation. Using DEREG mice, which allow conditional and efficient depletion of Foxp3+ Tregs by diphtheria toxin injection, we observed that transient Foxp3+ Treg depletion immediately after nonablative oligofractionated irradiation provided synergistic local control and biased the T cell repertoire toward central and effector memory T cells, resulting in long-term cure. Furthermore, this combination therapy showed significant abscopal effect on the nonirradiated tumors in a concomitant model of mesothelioma through systemic activation of cytotoxic T cells and enhanced production of IFN-γ and granzyme B. Although local control was preserved with one fraction of nonablative irradiation, three fractions were required to generate the abscopal effect. PD-1 and CTLA-4 were upregulated on tumor-infiltrating CD4+ and CD8+ T cells in irradiated and nonirradiated tumors, suggesting that immune checkpoint inhibitors could be beneficial after LRT and Foxp3+ Treg depletion. Our findings are applicable to the strategy of immuno-radiotherapy for generating optimal antitumor immune responses in the clinical setting. Targeting Tregs immediately after a short course of irradiation could have a major impact on the local response to irradiation and its abscopal effect.


Assuntos
Fatores de Transcrição Forkhead/imunologia , Mesotelioma Maligno/imunologia , Linfócitos T Reguladores/imunologia , Animais , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Antígeno CTLA-4/imunologia , Granzimas/imunologia , Imunidade/imunologia , Interferon gama/imunologia , Depleção Linfocítica/métodos , Linfócitos do Interstício Tumoral/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Receptor de Morte Celular Programada 1/imunologia , Linfócitos T Citotóxicos/imunologia , Microambiente Tumoral/imunologia
4.
BMC Cancer ; 18(1): 471, 2018 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-29699510

RESUMO

BACKGROUND: Cancer cell repopulation during chemotherapy or radiotherapy is a major factor limiting the efficacy of treatment. Cancer stem cells (CSC) may play critical roles during this process. We aim to demonstrate the role of mesothelioma stem cells (MSC) in treatment failure and eventually to design specific target therapies against MSC to improve the efficacy of treatment in malignant mesothelioma. METHODS: Murine mesothelioma AB12 and RN5 cells were used to compare tumorigenicity in mice. The expression of CSC-associated genes was evaluated by quantitative real-time PCR in both cell lines treated with chemo-radiation. Stemness properties of MSC-enriched RN5-EOS-Puro2 cells were characterized with flow cytometry and immunostaining. A MSC-specific gene profile was screened by microarray assay and confirmed thereafter. Gene Ontology analysis of the selected genes was performed by GOMiner. RESULTS: Tumor growth delay of murine mesothelioma AB12 cells was achieved after each cycle of cisplatin treatment, however, tumors grew back rapidly due to cancer cell repopulation between courses of chemotherapy. Strikingly, a 10-times lower number of irradiated cells in both cell lines led to a similar tumor incidence and growth rate as with untreated cells. The expression of CSC-associated genes such as CD24, CD133, CD90 and uPAR was dramatically up-regulated, while others did not change significantly after chemoradiation. Highly enriched MSC after selection with puromycin displayed an increasing GFP-positive population and showed typical properties of stemness. Comparatively, the proportion of MSC significantly increased after RN5-EOS parental cells were treated with either chemotherapy, γ-ray radiation, or a combination of the two, while MSC showed more resistance to the above treatments. A group of identified genes are most likely MSC-specific, and major pathways related to regulation of cell growth or apoptosis are involved. Upregulation of the gene transcripts Tnfsf18, Serpinb9b, Ly6a, and Nppb were confirmed. CONCLUSION: Putative MSC possess the property of stemness showing more resistance to chemoradiation, suggesting that MSC may play critical roles in cancer cell repopulation. Further identification of selected genes may be used to design novel target therapies against MSC, so as to eliminate cancer cell repopulation in mesothelioma.


Assuntos
Mesotelioma/genética , Mesotelioma/metabolismo , Células-Tronco Neoplásicas/metabolismo , Animais , Linhagem Celular Tumoral , Sobrevivência Celular , Quimiorradioterapia/efeitos adversos , Quimiorradioterapia/métodos , Biologia Computacional/métodos , Modelos Animais de Doenças , Resistencia a Medicamentos Antineoplásicos , Citometria de Fluxo , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Mesotelioma/patologia , Mesotelioma/terapia , Camundongos , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/efeitos da radiação , Tolerância a Radiação/genética , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Clin Cancer Res ; 23(4): 1060-1067, 2017 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-27683181

RESUMO

Purpose: Malignant pleural mesothelioma (MPM) is a rare but aggressive disease with few therapeutic options. The tumor-stromal interface is important in MPM, but this is lost in cell lines, the main model used for preclinical studies. We sought to characterize MPM patient-derived xenografts (PDX) to determine their suitability as preclinical models and whether tumors that engraft reflect a more aggressive biological phenotype.Experimental Design: Fresh tumors were harvested from extrapleural pneumonectomy, decortication, or biopsy samples of 50 MPM patients and implanted subcutaneously into immunodeficient mice and serially passaged for up to five generations. We correlated selected mesothelioma biomarkers between PDX and patient tumors, and PDX establishment with the clinical pathologic features of the patients, including their survival. DNA of nine PDXs was profiled using the OncoScan FFPE Express platform. Ten PDXs were treated with cisplatin and pemetrexed.Results: A PDX was formed in 20 of 50 (40%) tumors implanted. Histologically, PDX models closely resembled the parent tumor. PDX models formed despite preoperative chemotherapy and radiotherapy. In multivariable analysis, patients whose tumors formed a PDX had significantly poorer survival when the model was adjusted for preoperative treatment (HR, 2.46; 95% confidence interval, 1.1-5.52; P = 0.028). Among 10 models treated with cisplatin, seven demonstrated growth inhibition. Genomic abnormalities seen in nine PDX models were similar to that previously reported.Conclusions: Patients whose tumors form PDX models have poorer clinical outcomes. MPM PDX tumors closely resemble the genotype and phenotype of parent tumors, making them valuable models for preclinical studies. Clin Cancer Res; 23(4); 1060-7. ©2016 AACR.


Assuntos
Proliferação de Células/efeitos dos fármacos , Cisplatino/administração & dosagem , Neoplasias Pulmonares/tratamento farmacológico , Mesotelioma/tratamento farmacológico , Animais , Linhagem Celular Tumoral , Cisplatino/efeitos adversos , Humanos , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/cirurgia , Mesotelioma/patologia , Mesotelioma/cirurgia , Mesotelioma Maligno , Camundongos , Pemetrexede/administração & dosagem , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Oncotarget ; 6(14): 12468-80, 2015 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-25980578

RESUMO

We previously demonstrated that blockade of immune suppressive CTLA-4 resulted in tumor growth delay when combined with chemotherapy in murine mesothelioma. Tumor-infiltrating T cells (TIT) after local radiotherapy (LRT) play critical roles in abscopal effect against cancer. We attempt to improve the local and abscopal effect by modulating T cell immunity with systemic blockade of CTLA-4 signal.The growth of primary tumors was significantly inhibited by LRT while CTLA-4 antibody enhanced the antitumor effect. Growth delay of the second tumors was achieved when the primary tumor was radiated. LRT resulted in more T cell infiltration into both tumors, including Treg and cytotoxic T cells. Interestingly, the proportion of Treg over effector T cells in both tumors was reversed after CTLA-4 blockade, while CD8 T cells were further activated. The expression of the immune-related genes was upregulated and cytokine production was significantly increased. LRT resulted in an increase of TIT, while CTLA-4 blockade led to significant reduction of Tregs and increase of cytotoxic T cells in both tumors. The abscopal effect is enhanced by targeting the immune checkpoints through modulation of T cell immune response in murine mesothelioma.


Assuntos
Antígeno CTLA-4/antagonistas & inibidores , Imunoterapia/métodos , Mesotelioma/imunologia , Neoplasias Pleurais/imunologia , Linfócitos T/imunologia , Animais , Anticorpos Monoclonais/farmacologia , Terapia Combinada , Modelos Animais de Doenças , Feminino , Citometria de Fluxo , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/efeitos da radiação , Mesotelioma/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos NOD , Camundongos SCID , Neoplasias Pleurais/patologia , Reação em Cadeia da Polimerase , Radioterapia/métodos , Linfócitos T/efeitos da radiação
7.
Cancer Immunol Immunother ; 63(12): 1285-96, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25183171

RESUMO

We studied the impact of natural killer T (NKT) cell activation by alpha-galactocysylceramide (α-GalCer, α-GC) on cancer cell repopulation during chemotherapy in murine mesothelioma. The number of NKT cells was found to be increased during the development of murine mesothelioma. NKT cells specifically recognize α-GC through CD1d resulting in their activation and expansion. Tumor-bearing mice were treated with chemotherapy once weekly, and α-GC was followed after each cycle of chemotherapy. Anti-tumor effect was evaluated on wild-type (WT) and CD1d knockout (CD1dKO) mice. Cancer cell proliferation and apoptosis were evaluated by Ki67 and TUNEL immunohistochemistry. CD4(+) and CD8(+) T cell proportion and activation in tumor, spleen, draining lymph node and peripheral blood were determined by flow cytometry, and gene expression of activated T cell-related cytokines was quantified by reverse transcription PCR. NKT cells were identified by CD1d-α-GC-tetramer staining. In WT mice, tumor growth delay was achieved by cisplatin (Cis), and this effect was improved in combination with α-GC, but α-GC alone had little effect. Cancer cell proliferation during chemotherapy was significantly inhibited by α-GC, while cancer cell death was significantly upregulated. α-GC following chemotherapy resulted in NKT cell expansion and an increase of interferon-γ production in the draining lymph node, blood and spleen. Gene expression of immune-associated cytokines was upregulated. Strikingly, the percentage of inducible T cell co-stimulator(+)CD4 T cells, Th17/Tc17 cells increased in splenocytes. In CD1d KO mice, however, Cis alone was less effective and Cis + α-GC provided no additional benefit over Cis alone. α-GC alone had minimal effect in both mice. NKT activation between cycles of chemotherapy could improve the outcome of mesothelioma treatment.


Assuntos
Antígenos CD1d/imunologia , Galactosilceramidas/farmacologia , Mesotelioma/imunologia , Mesotelioma/terapia , Células T Matadoras Naturais/imunologia , Animais , Terapia Combinada , Modelos Animais de Doenças , Feminino , Genótipo , Imuno-Histoquímica , Imunoterapia/métodos , Mesotelioma/tratamento farmacológico , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout
8.
J Immunother ; 36(8): 391-9, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23994885

RESUMO

CD1d-restricted natural killer T (iNKT) cells have been shown to provide adjuvant activity against cancer by producing interferon (IFN)-γ. However, the role of invariant NKT (iNKT) cells in the tumor microenvironment has not yet been fully addressed. Our aim is to elucidate the antitumor effect of iNKT cells in the tumor microenvironment by using an intrathoracic murine malignant pleural mesothelioma model that we had previously developed and to provide pleural effusion as a good surrogate of the tumor microenvironment. We found that the number of iNKT cells increased dramatically in the pleural effusion after intrathoracic tumor cell injection at an earlier phase compared with accumulation of CD8 T cells. These iNKT cells showed increased expression of CD25 and increased ratio of cells positive for IFN-γ intracellular staining. iNKT cells sorted from pleural effusion of tumor burden mice produced larger amount of IFN-γ compared with naive mice. Mice pretreated in vivo with anti-CD1d-blocking Ab showed increased amount of pleural effusion and decreased ratio of total and effector-type CD8 T cells as well as decreased intracellular IFN-γ expression of CD8T-cell in the pleural effusion. In vivo administration of α-galactosylceramide (α-GalCer) showed prolonged survival associated with less pleural effusion and increased ratio of IFN-γ-positive iNKT cells and CD8 T cells in the pleural effusion. Therefore, this study suggests that iNKT cells accumulating in the tumor microenvironment play an antitumor effect by producing IFN-γ and enhancing subsequent CD8 T-cell response. Furthermore, in vivo administration of α-GalCer could suppress mesothelioma growth by activating iNKT cells.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Interferon gama/metabolismo , Neoplasias Pulmonares/imunologia , Mesotelioma/imunologia , Células T Matadoras Naturais/imunologia , Neoplasias Pleurais/imunologia , Animais , Anticorpos Bloqueadores/administração & dosagem , Antígenos CD1d/imunologia , Antígenos CD1d/metabolismo , Processos de Crescimento Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Feminino , Galactosilceramidas/administração & dosagem , Neoplasias Pulmonares/patologia , Mesotelioma/patologia , Mesotelioma Maligno , Camundongos , Camundongos Endogâmicos BALB C , Células T Matadoras Naturais/efeitos dos fármacos , Transplante de Neoplasias , Derrame Pleural Maligno/imunologia , Neoplasias Pleurais/patologia , Carga Tumoral/efeitos dos fármacos , Microambiente Tumoral/imunologia
9.
Mol Cancer Ther ; 11(8): 1809-19, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22584123

RESUMO

Cancer immunotherapy has shown promising results when combined with chemotherapy. Blocking CTLA-4 signaling by monoclonal antibody between cycles of chemotherapy may inhibit cancer cell repopulation and enhance the antitumoral immune reaction, thus improve the efficacy of chemotherapy in mesothelioma. The impact of CTLA-4 blockade on the early stage of tumor development was evaluated in a subcutaneous murine mesothelioma model. CTLA-4 blocking antibody was administered following each cycle of chemotherapy, and monotherapy was included as controls. Antitumor effect was evaluated by tumor growth delay and survival of the animals. Tumor cell repopulation was quantified by bromodeoxyuridine incorporation and Ki67 by immunohistochemistry and/or flow cytometry. In vitro cell killing was determined by classic chromium-released assay, and reverse transcription PCR (RT-PCR) was carried out to determine the gene expression of associated cytokines. Anti-CTLA-4 monoclonal antibody was able to inhibit tumor growth at early stage of tumor development. Antitumor effect was achieved by administration of CTLA-4 blockade between cycles of chemotherapy. Tumor cell repopulation during the intervals of cisplatin was inhibited by CTLA-4 blockade. Anti-CTLA-4 therapy gave rise to an increased number of CD4 and CD8 T cells infiltrating the tumor. RT-PCR showed that the gene expression of interleukin IL-2, IFN-γ, granzyme B, and perforin increased in the tumor milieu. Blockade of CTLA-4 signaling showed effective anticancer effect, correlating with inhibiting cancer cell repopulation between cycles of chemotherapy and upregulating tumor-infiltrating T lymphocytes, cytokines, and cytolytic enzymes in a murine mesothelioma model.


Assuntos
Anticorpos Monoclonais/farmacologia , Antígeno CTLA-4/antagonistas & inibidores , Linfócitos do Interstício Tumoral/imunologia , Mesotelioma/imunologia , Linfócitos T/imunologia , Animais , Anticorpos Monoclonais/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Antígeno CTLA-4/imunologia , Linhagem Celular Tumoral , Citocinas/imunologia , Modelos Animais de Doenças , Feminino , Granzimas/genética , Granzimas/metabolismo , Ativação Linfocitária/genética , Ativação Linfocitária/imunologia , Depleção Linfocítica , Linfócitos do Interstício Tumoral/metabolismo , Mesotelioma/tratamento farmacológico , Mesotelioma/mortalidade , Mesotelioma/patologia , Camundongos , Perforina/genética , Perforina/metabolismo , Carga Tumoral/efeitos dos fármacos , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/imunologia
10.
Chest ; 141(3): 661-673, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21835902

RESUMO

BACKGROUND: Pulmonary hypertension (PH) associated with pulmonary fibrosis (PF) is a severe condition with poor outcome. It is unknown whether patients with PF with associated PH (APH) represent a distinct phenotype of the disease. We hypothesized that the lung tissue gene expression pattern of patients with APH has a characteristic profile when compared with patients with PF without APH. We sought to determine if different gene expression signatures in PF could be determined based on pulmonary arterial pressures (PAPs) and to provide new insights into the pathobiology of APH. METHODS: Microarray analysis (Affymetrix) was performed after RNA was extracted from explanted lungs in 116 consecutive patients with PF (development set, n = 84; validation set, n = 32) and seven subjects with idiopathic pulmonary arterial hypertension undergoing lung transplant (LTx). PAP were recorded intraoperatively immediately before starting LTx. The development set was divided into three groups according to mean PAP (mPAP): severe PH group (mPAP ≥ 40 mm Hg, n = 17); intermediate PH group (mPAP 21-39 mm Hg, n = 45); NoPH group (mPAP ≤ 20 mm Hg, n = 22). RESULTS: Distinct gene signatures were observed. Patients in the severe PH group showed increased expression of genes, gene sets, and networks related to myofibroblast proliferation and vascular remodeling, whereas patients in the NoPH group strongly expressed proinflammatory genes. Two-dimensional hierarchic clustering based on 222 differentially expressed genes (severe PH vs no PH) dichotomized subjects into two phenotypes in the intermediate PH group and in the validation set. Real-time polymerase chain reaction confirmed the differential expression of selected genes. CONCLUSIONS: Gene expression profiles distinguish PF phenotypes with and without APH. This observation can have important implications for future trials.


Assuntos
Perfilação da Expressão Gênica , Hipertensão Pulmonar/epidemiologia , Hipertensão Pulmonar/genética , Pulmão/metabolismo , Fibrose Pulmonar/epidemiologia , Fibrose Pulmonar/genética , Adulto , Idoso , Pressão Sanguínea , Comorbidade , Diagnóstico Diferencial , Feminino , Humanos , Hipertensão Pulmonar/diagnóstico , Pulmão/patologia , Pulmão/cirurgia , Transplante de Pulmão , Masculino , Análise em Microsséries , Pessoa de Meia-Idade , Fenótipo , Fibrose Pulmonar/diagnóstico
11.
J Thorac Oncol ; 6(9): 1578-86, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21642867

RESUMO

INTRODUCTION: Malignant pleural mesothelioma is a highly aggressive cancer with poor prognosis. We have previously demonstrated that regulatory T cells (Treg) depletion can impact tumor microenvironment when combined with chemotherapy. The aim of this study is to analyze the impact of Treg depletion on tumor cell repopulation during cycles of chemotherapy in a murine mesothelioma model. METHODS: Tumor-bearing mice were treated with chemotherapy once weekly to mimic clinical settings and with PC61 to cause Treg depletion after each cycle of chemotherapy. Tumor cell repopulation was evaluated by BrdU labeling index with immunohistochemistry and flow cytometry, and Ki67 gene expression was determined by real-time reverse-transcribed polymerase chain reaction. The proportion of CD4+ CD25+Foxp3+ Tregs, CD4+, and CD8+ T cells in the tumor, spleen, draining lymph node, and peripheral blood from tumor-bearing mice was determined by using flow cytometry, and gene expression of activated T-cell-related cytokines was quantified by enzyme-linked immunosorbent assay and reverse-transcribed polymerase chain reaction. RESULTS: Tumor growth delay was achieved by cisplatin followed by PC61 or cyclophosphamide. The BrdU labeling index indicated that tumor cell repopulation between cycles of cisplatin was significantly inhibited by PC61. The CD4+CD25+Foxp3+ Tregs in tumor and lymphoid organs were almost completely depleted, whereas the CD4+ or CD8+ T cells did not change. PC61 after chemotherapy resulted in an increase of gene expression of interferon-γ, granzyme B, perforin, and IP-10, thus leading to tumor cell lysis in cytotoxic lymphocyte assay. Nevertheless, cell killing induced by cyclophosphamide combined with cisplatin was due to cytotoxicity rather than specific immune response. CONCLUSION: Treg depletion between cycles of chemotherapy could improve the outcome of mesothelioma. Nevertheless, this effect seems limited, and more effective approaches need to be developed.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Mesotelioma/tratamento farmacológico , Mesotelioma/imunologia , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/imunologia , Animais , Anticorpos Monoclonais/farmacologia , Proliferação de Células , Cisplatino/administração & dosagem , Ciclofosfamida/administração & dosagem , Citocinas/genética , Citocinas/metabolismo , Feminino , Citometria de Fluxo , Ativação Linfocitária , Mesotelioma/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Linfócitos T Citotóxicos , Linfócitos T Reguladores/citologia
12.
J Immunol ; 185(2): 956-66, 2010 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-20548032

RESUMO

CD4(+)CD25(+) regulatory T cells (Tregs) can promote the growth of some tumors, but it is unknown whether this is true for all tumors, including malignant pleural mesothelioma. We have previously shown that the existence of Tregs was associated with poor survival in patients with malignant pleural mesothelioma. In this study, using an intrathoracic murine model of malignant mesothelioma (MM), we provide evidence suggesting that Treg blockade could enhance survival when combined with pemetrexed in established tumor. AC29 murine MM cells were injected into the right pleural cavity of CBA mice for tumor development. Four days after the tumor injection, tumor-bearing mice were then treated with pemetrexed alone, Treg blockade alone, or a combination of pemetrexed and Treg blockade. We observed a synergistic antitumor effect of Treg blockade combined with pemetrexed resulting in prolonged survival. The combination of Treg blockade and pemetrexed was associated with decreased tumor-infiltrating Tregs, increased IL-2 production, dendritic cell maturation, and increased CD3(+)CD8(+)IFN-gamma(+) tumor-infiltrating T cells when compared with mice treated with pemetrexed alone or Treg blockade alone. The survival benefit was abrogated if anti-CD8 mAb was administered simultaneously. Likewise, the survival benefit resulting from the combined Treg blockade with pemetrexed was not observed when immunodeficient mice were used. Therefore, this study suggests that Treg blockade combined with pemetrexed can suppress mesothelioma growth in established tumor in vivo through an immune-mediated process. This study also validates a new intrathoracic tumor model of pleural effusion to explore the role of antitumor immunity in murine MM.


Assuntos
Anticorpos Monoclonais/imunologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Mesotelioma/tratamento farmacológico , Neoplasias Pleurais/tratamento farmacológico , Linfócitos T Reguladores/imunologia , Animais , Anticorpos Monoclonais/administração & dosagem , Antígenos CD4/imunologia , Antígenos CD8/imunologia , Linhagem Celular Tumoral , Sinergismo Farmacológico , Feminino , Glutamatos/administração & dosagem , Guanina/administração & dosagem , Guanina/análogos & derivados , Subunidade alfa de Receptor de Interleucina-2/imunologia , Mesotelioma/imunologia , Mesotelioma/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos CBA , Camundongos Endogâmicos NOD , Camundongos SCID , Pemetrexede , Neoplasias Pleurais/imunologia , Neoplasias Pleurais/patologia , Análise de Sobrevida , Linfócitos T Reguladores/citologia , Linfócitos T Reguladores/efeitos dos fármacos , Resultado do Tratamento
13.
J Thorac Cardiovasc Surg ; 135(4): 823-9, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18374762

RESUMO

OBJECTIVE: The aim of the study was to determine the impact of tumor-infiltrating lymphocytes on survival in patients with malignant pleural mesothelioma treated with induction chemotherapy followed by extrapleural pneumonectomy. METHODS: We performed an immunohistochemical analysis of 32 extrapleural pneumonectomy specimens to assess the distribution of T-cell subtypes (CD3(+), CD4(+), and CD8(+)), regulatory subtypes (CD25(+) and FOXP3(+)), and memory subtype (CD45RO(+)) within the tumor. RESULTS: Patients with high levels of CD8(+) tumor-infiltrating lymphocytes demonstrated better survival than those with low levels (3-year survival: 83% vs 28%; P = .06). Moreover, high levels of CD8(+) tumor-infiltrating lymphocytes were associated with a lower incidence of mediastinal node disease (P = .004) and longer progression-free survival (P = .05). Higher levels of CD8(+) tumor-infiltrating lymphocytes were observed in patients treated with cisplatin and pemetrexed than in those treated with cisplatin and vinorelbine (P = .02). Patients presenting high levels of CD4(+) or CD25(+) tumor-infiltrating lymphocytes or low levels of CD45RO(+) also demonstrated a trend toward shorter survival. However, the presence of FOXP3(+) tumor-infiltrating lymphocytes did not affect survival. After multivariate adjustment, high levels of CD8(+) tumor-infiltrating lymphocytes remained an independent prognostic factor associated with delayed recurrence (hazard ratio = 0.38; confidence interval = 0.09-0.87; P = .02) and better survival (hazard ratio = 0.39; confidence interval = 0.09-0.89; P = .02). CONCLUSION: The presence of high levels of CD8(+) tumor-infiltrating lymphocytes is associated with better prognosis in patients undergoing extrapleural pneumonectomy for malignant pleural mesothelioma. The stimulation of CD8(+) lymphocytes can be a potential therapeutic strategy to improve outcome.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Linfócitos do Interstício Tumoral/imunologia , Mesotelioma/terapia , Neoplasias Pleurais/terapia , Subpopulações de Linfócitos T/imunologia , Adulto , Idoso , Antineoplásicos/uso terapêutico , Feminino , Humanos , Masculino , Mesotelioma/imunologia , Pessoa de Meia-Idade , Terapia Neoadjuvante , Neoplasias Pleurais/imunologia , Pneumonectomia , Prognóstico , Análise de Sobrevida
14.
J Virol ; 79(14): 9270-84, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15994821

RESUMO

The ERV3 locus at chromosome 7q11 is a much studied human endogenous retroviral (HERV) sequence, owing to an env open reading frame (ORF) and placental RNA and protein expression. An analysis of the human genome demonstrated that ERV3 is one of a group of 41 highly related elements (ERV3-like HERVs) which use proline, isoleucine, or arginine tRNA in their primer binding sites. In addition to elements closely related to ERV3, the group included the previously known retinoic acid-inducible element, RRHERVI, also referred to as HERV15, but was separate from the related HERV-E elements. The ERV3-like elements are defective. The only element with an ORF among gag, pro, pol, and env genes was the env ORF of the original ERV3 locus. A search in dbEST revealed ERV3 RNA expression in placenta, skin, carcinoid tumor, and adrenal glands. Expression was also studied with newly developed real-time quantitative PCRs (QPCR) of ERV3 and HERV-E(4-1) env sequences. Results from a novel histone 3.3 RNA QPCR result served as the expression control. QPCR results for ERV3 were compatible with previously published results, with a stronger expression in adrenal gland and placenta than in 15 other human tissues. The expression of the envelope (env) of ERV3 at chromosome 7q11 was also studied by using stringent in situ hybridization. Expression was found in corpus luteum, testis, adrenal gland, Hassal's bodies in thymus, brown fat, pituitary gland, and epithelium of the lung. We conclude that ERV3 env is most strongly expressed in adrenal and sebaceous glands as well as in placenta.


Assuntos
Retrovirus Endógenos/genética , RNA Viral/química , Sequência de Aminoácidos , Sequência de Bases , Mapeamento Cromossômico , Cromossomos Humanos Par 7 , Retrovirus Endógenos/isolamento & purificação , Etiquetas de Sequências Expressas , Humanos , Hibridização In Situ , Dados de Sequência Molecular , Especificidade de Órgãos , RNA Viral/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sequências Repetidas Terminais , Proteínas do Envelope Viral/genética
15.
J Virol Methods ; 129(1): 16-30, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15967513

RESUMO

Endogenous retroviral sequences (ERVs) are dynamic genomic components with profound influences on gene expression and genomic structure. Their extent of expression is not well known. Several broadly targeted real-time reverse transcription PCR (QPCRs) systems for surveillance of RNA expression of the major groups of human gammaretroviral ERVs were constructed. The highly conserved reverse transcriptase (RT) and integrase (IN) domains of the pol gene were used as targets for the PCRs, which were both probe-based (TaqMan) and probe-less (SYBR Green). Different levels of primer and probe degeneracy, with or without inosine, were tested. Several of the PCRs had sensitivities of a few HERV nucleic acid copies per PCR reaction. Specificities were approximately as expected from the fit of primers and probes. Gammaretroviral HERV RNA expression was studied in different human tissues. Each HERV group had a specific pattern of expression. HERV-E was highly expressed in testis, HERV-I/T in brain and testis, HERV-H in brain and testis, while HERV-W was highly expressed in placenta. Gammaretroviral RNA was not detected in plasma from 50 blood donors in saliva from 20 persons. In conclusion, a set of tools for investigation of gammaretroviral HERV RNA expression was created.


Assuntos
Gammaretrovirus/genética , Genes pol/genética , Reação em Cadeia da Polimerase/métodos , RNA Viral/análise , Sequência de Bases , Benzotiazóis , Diaminas , Expressão Gênica , Humanos , Dados de Sequência Molecular , Compostos Orgânicos/metabolismo , Quinolinas , RNA Viral/genética
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