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1.
medRxiv ; 2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38106077

RESUMO

Background: Understanding the kinetics and longevity of antibody responses to SARS-CoV-2 is critical to informing strategies toward reducing Coronavirus disease 2019 (COVID-19) reinfections, and improving vaccination and therapy approaches. Methods: We evaluated antibody titers against SARS-CoV-2 nucleocapsid (N), spike (S), and receptor binding domain (RBD) of spike in 98 convalescent participants who experienced asymptomatic, mild, moderate or severe COVID-19 disease and in 17 non-vaccinated, non-infected controls, using four different antibody assays. Participants were sampled longitudinally at 1, 3, 6, and 12 months post-SARS-CoV-2 positive PCR test. Findings: Increasing acute COVID-19 disease severity correlated with higher anti-N and anti-RBD antibody titers throughout 12 months post-infection. Anti-N and anti-RBD titers declined over time in all participants, with the exception of increased anti-RBD titers post-vaccination, and the decay rates were faster in hospitalized compared to non-hospitalized participants. <50% of participants retained anti-N titers above control levels at 12 months, with non-hospitalized participants falling below control levels sooner. Nearly all hospitalized and non-hospitalized participants maintained anti-RBD titers above controls for up to 12 months, suggesting longevity of protection against severe reinfections. Nonetheless, by 6 months, few participants retained >50% of their 1-month anti-N or anti-RBD titers. Vaccine-induced increases in anti-RBD titers were greater in non-hospitalized relative to hospitalized participants. Early convalescent antibody titers correlated with age, but no association was observed between Post-Acute Sequelae of SARS-CoV-2 infection (PASC) status or acute steroid treatment and convalescent antibody titers. Interpretation: Hospitalized participants developed higher anti-SARS-CoV-2 antibody titers relative to non-hospitalized participants, a difference that persisted throughout 12 months, despite the faster decline in titers in hospitalized participants. In both groups, while anti-N titers fell below control levels for at least half of the participants, anti-RBD titers remained above control levels for almost all participants over 12 months, demonstrating generation of long-lived antibody responses known to correlate with protection from severe disease across COVID-19 severities. Overall, our findings contribute to the evolving understanding of COVID-19 antibody dynamics. Funding: Austin Public Health, NIAAA, Babson Diagnostics, Dell Medical School Startup.

2.
Front Immunol ; 14: 1260545, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37744352

RESUMO

Histone deacetylase inhibitors (HDACi) are currently being explored for the treatment of both solid and hematological malignancies. Although originally thought to exert cytotoxic responses through tumor-intrinsic mechanisms by increasing expression of tumor suppressor genes, several studies have demonstrated that therapeutic responses depend on an intact adaptive immune system: particularly CD8 T cells. It is therefore critical to understand how HDACi directly affects T cells in order to rationally design regimens for combining with immunotherapy. In this study, we evaluated T cell responses to a novel class-selective HDACi (OKI-179, bocodepsin) by assessing histone acetylation levels, which revealed rapid responsiveness accompanied by an increase in CD4 and CD8 T cell frequencies in the blood. However, these rapid responses were transient, as histone acetylation and frequencies waned within 24 hours. This contrasts with in vitro models where high acetylation was sustained and continuous exposure to HDACi suppressed cytokine production. In vivo comparisons demonstrated that stopping OKI-179 treatment during PD-1 blockade was superior to continuous treatment. These findings provide novel insight into the direct effects of HDAC inhibitors on T cells and that treatment schedules that take into account acute T cell effects should be considered when combined with immunotherapies in order to fully harness the tumor-specific T cell responses in patients.


Assuntos
Inibidores de Histona Desacetilases , Histonas , Humanos , Inibidores de Histona Desacetilases/farmacologia , Imunoterapia , Protocolos Clínicos , Linfócitos T CD8-Positivos
3.
J Immunother Cancer ; 11(6)2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37399356

RESUMO

Anticancer immunotherapies, such as immune checkpoint inhibitors, bispecific antibodies, and chimeric antigen receptor T cells, have improved outcomes for patients with a variety of malignancies. However, most patients either do not initially respond or do not exhibit durable responses due to primary or adaptive/acquired immune resistance mechanisms of the tumor microenvironment. These suppressive programs are myriad, different between patients with ostensibly the same cancer type, and can harness multiple cell types to reinforce their stability. Consequently, the overall benefit of monotherapies remains limited. Cutting-edge technologies now allow for extensive tumor profiling, which can be used to define tumor cell intrinsic and extrinsic pathways of primary and/or acquired immune resistance, herein referred to as features or feature sets of immune resistance to current therapies. We propose that cancers can be characterized by immune resistance archetypes, comprised of five feature sets encompassing known immune resistance mechanisms. Archetypes of resistance may inform new therapeutic strategies that concurrently address multiple cell axes and/or suppressive mechanisms, and clinicians may consequently be able to prioritize targeted therapy combinations for individual patients to improve overall efficacy and outcomes.


Assuntos
Anticorpos Biespecíficos , Neoplasias , Humanos , Neoplasias/tratamento farmacológico , Imunoterapia , Anticorpos Biespecíficos/farmacologia , Anticorpos Biespecíficos/uso terapêutico , Microambiente Tumoral
4.
Cancers (Basel) ; 16(1)2023 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-38201519

RESUMO

(1) Background: Histone deacetylases (HDACs) play a critical role in epigenetic signaling in cancer; however, available HDAC inhibitors have limited therapeutic windows and suboptimal pharmacokinetics (PK). This first-in-human phase I dose escalation study evaluated the safety, PK, pharmacodynamics (PDx), and efficacy of the oral Class I-targeting HDAC inhibitor bocodepsin (OKI-179). (2) Patients and Methods: Patients (n = 34) with advanced solid tumors were treated with OKI-179 orally once daily in three schedules: 4 days on 3 days off (4:3), 5 days on 2 days off (5:2), or continuous in 21-day cycles until disease progression or unacceptable toxicity. Single-patient escalation cohorts followed a standard 3 + 3 design. (3) Results: The mean duration of treatment was 81.2 (range 11-447) days. The most frequent adverse events in all patients were nausea (70.6%), fatigue (47.1%), and thrombocytopenia (41.2%). The maximum tolerated dose (MTD) of OKI-179 was 450 mg with 4:3 and 200 mg with continuous dosing. Dose-limiting toxicities included decreased platelet count and nausea. Prolonged disease control was observed, including two patients with platinum-resistant ovarian cancer. Systemic exposure to the active metabolite exceeded the preclinical efficacy threshold at doses lower than the MTD and was temporally associated with increased histone acetylation in circulating T cells. (4) Conclusions: OKI-179 has a manageable safety profile at the recommended phase 2 dose (RP2D) of 300 mg daily on a 4:3 schedule with prophylactic oral antiemetics. OKI-179 is currently being investigated with the MEK inhibitor binimetinib in patients with NRAS-mutated melanoma in the phase 2 Nautilus trial.

5.
Mult Scler Relat Disord ; 68: 104195, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36223705

RESUMO

BACKGROUND AND OBJECTIVES: During the COVID-19 pandemic, B cell depleting therapies pose a clinical concern for patients with neuroimmune conditions, as patients may not mount a sufficient immune response to SARS-CoV-2 infection and vaccinations. Studies to-date have reported conflicting results on the degree of antibody production post-SARS-CoV-2 infection and vaccinations in B cell depleted patients, focusing primarily on short-term immune profiling. Our objective was to follow longitudinal immune responses in COVID-19 B cell depleted patients with neuroimmune disorders post-COVID-19 and SARS-CoV-2-vaccination. METHODS: CD20 B cell depleted autoimmune patients and age/sex-matched controls positive for SARS-CoV-2 were recruited at Dell Medical School, UT Austin between 2020 and 2021, followed prospectively for 12 months and evaluated at multiple time points for spike S1 receptor binding domain (RBD) antibody titers, B and T cell composition, and frequency of T cells specific for SARS-CoV-2 antigens. RESULTS: Immune responses post-SARS-CoV-2 infection and vaccination were evaluated in a cohort of COVID-19 B cell depleted neuroimmune patients (n = 5), COVID-19 non-B cell depleted autoimmune patients (n = 15), COVID-19 immunocompetent patients (n = 117), and healthy controls (n = 6) for a total of 259 samples in 137 participants. 4/5 B cell-depleted patients developed detectable anti-spike RBD antibodies, which were boosted by vaccination in 2 patients. While spike RBD antibodies were associated with presence of CD20+ B cells, very few B cells were required. In contrast, patients whose B cell compartment primarily consisted of CD19+CD20- Bcells during acute COVID-19 disease or vaccination did not seroconvert. Interestingly, circulating Bcells in B cell depleted patients were significantly CD38high with co-expression of CD24 and CD27, indicating that B cell depletion may impact B cell activation patterns. Additionally, all B cell depleted patients mounted a sustained T cell response to SARS-CoV-2 antigens, regardless of seroconversion. Specifically, all patients developed naïve, central memory, effector memory, and effector memory RA+ T cells, suggesting intact T cell memory conversion in B cell depleted patients compared to controls. DISCUSSION: We present the longest COVID-19 immune profiling analysis to date in B cell depleted patients, demonstrating that both humoral and cellular immune responses can be generated and sustained up to 12 months post SARS-CoV-2 infection and vaccination. Notably, failure to establish humoral immunity did not result in severe disease. We also highlight specific T and B cell signatures that could be used as clinical biomarkers to advise patients on timing of SARS-CoV-2 vaccinations.


Assuntos
COVID-19 , Humanos , Lactente , SARS-CoV-2 , Pandemias , Autoimunidade , Pacientes , Vacinação , Anticorpos Antivirais
6.
Mol Cancer Ther ; 21(10): 1547-1560, 2022 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-35977156

RESUMO

The heterogeneity and aggressiveness of triple-negative breast cancer (TNBC) contribute to its early recurrence and metastasis. Despite substantial research to identify effective therapeutic targets, TNBC remains elusive in terms of improving patient outcomes. Here, we report that a covalent JNK inhibitor, JNK-IN-8, suppresses TNBC growth both in vitro and in vivo. JNK-IN-8 reduced colony formation, cell viability, and organoid growth in vitro and slowed patient-derived xenograft and syngeneic tumor growth in vivo. Cells treated with JNK-IN-8 exhibited large, cytoplasmic vacuoles with lysosomal markers. To examine the molecular mechanism of this phenotype, we looked at the master regulators of lysosome biogenesis and autophagy transcription factor EB (TFEB) and TFE3. JNK-IN-8 inhibited TFEB phosphorylation and induced nuclear translocation of unphosphorylated TFEB and TFE3. This was accompanied by an upregulation of TFEB/TFE3 target genes associated with lysosome biogenesis and autophagy. Depletion of both TFEB and TFE3 diminished the JNK-IN-8-driven upregulation of lysosome biogenesis and/or autophagy markers. TFEB and TFE3 are phosphorylated by a number of kinases, including mTOR. JNK-IN-8 reduced phosphorylation of mTOR targets in a concentration-dependent manner. Knockout of JNK1 and/or JNK2 had no impact on TFEB/TFE3 activation or mTOR inhibition by JNK-IN-8 but inhibited colony formation. Similarly, reexpression of either wildtype or drug-nonbinding JNK (C116S) in JNK knockout cells did not reverse JNK-IN-8-induced TFEB dephosphorylation. In summary, JNK-IN-8 induced lysosome biogenesis and autophagy by activating TFEB/TFE3 via mTOR inhibition independently of JNK. Together, these findings demonstrate the efficacy of JNK-IN-8 as a targeted therapy for TNBC and reveal its novel lysosome- and autophagy-mediated mechanism of action.


Assuntos
Neoplasias de Mama Triplo Negativas , Autofagia , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/farmacologia , Benzamidas , Humanos , Lisossomos , Piridinas , Pirimidinas , Serina-Treonina Quinases TOR , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/genética
7.
Addict Biol ; 26(2): e12889, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32176824

RESUMO

Alcohol abuse induces changes in microglia morphology and immune function, but whether microglia initiate or simply amplify the harmful effects of alcohol exposure is still a matter of debate. Here, we determine microglia function in acute and voluntary drinking behaviors using a colony-stimulating factor 1 receptor inhibitor (PLX5622). We show that microglia depletion does not alter the sedative or hypnotic effects of acute intoxication. Microglia depletion also does not change the escalation or maintenance of chronic voluntary alcohol consumption. Transcriptomic analysis revealed that although many immune genes have been implicated in alcohol abuse, downregulation of microglia genes does not necessitate changes in alcohol intake. Instead, microglia depletion and chronic alcohol result in compensatory upregulation of alcohol-responsive, reactive astrocyte genes, indicating astrocytes may play a role in regulation of these alcohol behaviors. Taken together, our behavioral and transcriptional data indicate that microglia are not the primary effector cell responsible for regulation of acute and voluntary alcohol behaviors. Because microglia depletion did not regulate acute or voluntary alcohol behaviors, we hypothesized that these doses were insufficient to activate microglia and recruit them to an effector phenotype. Therefore, we used a model of repeated immune activation using polyinosinic:polycytidylic acid (poly(I:C)) to activate microglia. Microglia depletion blocked poly(I:C)-induced escalations in alcohol intake, indicating microglia regulate drinking behaviors with sufficient immune activation. By testing the functional role of microglia in alcohol behaviors, we provide insight into when microglia are causal and when they are consequential for the transition from alcohol use to dependence.


Assuntos
Alcoolismo/patologia , Microglia/efeitos dos fármacos , Compostos Orgânicos/farmacologia , Consumo de Bebidas Alcoólicas/patologia , Intoxicação Alcoólica/patologia , Animais , Astrócitos/efeitos dos fármacos , Doença Crônica , Relação Dose-Resposta a Droga , Mediadores da Inflamação/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Destreza Motora/efeitos dos fármacos , Receptores de Fator Estimulador de Colônias/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Sono/efeitos dos fármacos
8.
Cancer Metastasis Rev ; 40(1): 7-30, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32929562

RESUMO

Recent developments in pre-clinical screening tools, that more reliably predict the clinical effects and adverse events of candidate therapeutic agents, has ushered in a new era of drug development and screening. However, given the rapid pace with which these models have emerged, the individual merits of these translational research tools warrant careful evaluation in order to furnish clinical researchers with appropriate information to conduct pre-clinical screening in an accelerated and rational manner. This review assesses the predictive utility of both well-established and emerging pre-clinical methods in terms of their suitability as a screening platform for treatment response, ability to represent pharmacodynamic and pharmacokinetic drug properties, and lastly debates the translational limitations and benefits of these models. To this end, we will describe the current literature on cell culture, organoids, in vivo mouse models, and in silico computational approaches. Particular focus will be devoted to discussing gaps and unmet needs in the literature as well as current advancements and innovations achieved in the field, such as co-clinical trials and future avenues for refinement.


Assuntos
Neoplasias , Pesquisa Translacional Biomédica , Animais , Técnicas de Cultura de Células , Humanos , Camundongos , Neoplasias/tratamento farmacológico , Organoides , Proteômica
9.
Blood ; 136(16): 1837-1850, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-32845007

RESUMO

Despite harboring mutations in oncogenes and tumor suppressors that promote cancer growth, T-cell acute lymphoblastic leukemia (T-ALL) cells require exogenous cells or signals to survive in culture. We previously reported that myeloid cells, particularly dendritic cells, from the thymic tumor microenvironment support the survival and proliferation of primary mouse T-ALL cells in vitro. Thus, we hypothesized that tumor-associated myeloid cells would support T-ALL in vivo. Consistent with this possibility, in vivo depletion of myeloid cells results in a significant reduction in leukemia burden in multiple organs in 2 distinct mouse models of T-ALL and prolongs survival. The impact of the myeloid compartment on T-ALL growth is not dependent on suppression of antitumor T-cell responses. Instead, myeloid cells provide signals that directly support T-ALL cells. Transcriptional profiling, functional assays, and acute in vivo myeloid-depletion experiments identify activation of IGF1R as a critical component of myeloid-mediated T-ALL growth and survival. We identify several myeloid subsets that have the capacity to directly support survival of T-ALL cells. Consistent with mouse models, myeloid cells derived from human peripheral blood monocytes activate IGF1R and directly support survival of primary patient T-ALL cells in vitro. Furthermore, enriched macrophage gene signatures in published clinical samples correlate with inferior outcomes for pediatric T-ALL patients. Collectively, these data reveal that tumor-associated myeloid cells provide signals critical for T-ALL growth in multiple organs in vivo and implicate tumor-associated myeloid cells and associated signals as potential therapeutic targets.


Assuntos
Comunicação Celular , Células Mieloides/imunologia , Células Mieloides/metabolismo , Leucemia-Linfoma Linfoblástico de Células T Precursoras/etiologia , Leucemia-Linfoma Linfoblástico de Células T Precursoras/metabolismo , Microambiente Tumoral , Biomarcadores , Linhagem Celular Tumoral , Perfilação da Expressão Gênica , Humanos , Macrófagos/imunologia , Macrófagos/metabolismo , Monócitos/imunologia , Monócitos/metabolismo , Células Mieloides/patologia , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patologia , Receptor IGF Tipo 1/genética , Receptor IGF Tipo 1/metabolismo , Transdução de Sinais
10.
BMC Cancer ; 20(1): 359, 2020 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-32345237

RESUMO

BACKGROUND: Therapy targeted to the human epidermal growth factor receptor type 2 (HER2) is used in combination with cytotoxic therapy in treatment of HER2+ breast cancer. Trastuzumab, a monoclonal antibody that targets HER2, has been shown pre-clinically to induce vascular changes that can increase delivery of chemotherapy. To quantify the role of immune modulation in treatment-induced vascular changes, this study identifies temporal changes in myeloid cell infiltration with corresponding vascular alterations in a preclinical model of HER2+ breast cancer following trastuzumab treatment. METHODS: HER2+ tumor-bearing mice (N = 46) were treated with trastuzumab or saline. After extraction, half of each tumor was analyzed by immunophenotyping using flow cytometry. The other half was quantified by immunohistochemistry to characterize macrophage infiltration (F4/80), vascularity (CD31 and α-SMA), proliferation (Ki67) and cellularity (H&E). Additional mice (N = 10) were used to quantify differences in tumor cytokines between control and treated groups. RESULTS: Immunophenotyping showed an increase in macrophage infiltration 24 h after trastuzumab treatment (P ≤ 0.05). With continued trastuzumab treatment, the M1 macrophage population increased (P = 0.02). Increases in vessel maturation index (i.e., the ratio of α-SMA to CD31) positively correlated with increases in tumor infiltrating M1 macrophages (R = 0.33, P = 0.04). Decreases in VEGF-A and increases in inflammatory cytokines (TNF-α, IL-1ß, CCL21, CCL7, and CXCL10) were observed with continued trastuzumab treatment (P ≤ 0.05). CONCLUSIONS: Preliminary results from this study in a murine model of HER2+ breast cancer show correlations between immune modulation and vascular changes, and reveals the potential for anti-HER2 therapy to reprogram immunosuppressive components of the tumor microenvironment. The quantification of immune modulation in HER2+ breast cancer, as well as the mechanistic insight of vascular alterations after anti-HER2 treatment, represent novel contributions and warrant further assessment for potential clinical translation.


Assuntos
Neoplasias da Mama/patologia , Modelos Animais de Doenças , Microvasos/imunologia , Células Mieloides/imunologia , Receptor ErbB-2/antagonistas & inibidores , Trastuzumab/farmacologia , Animais , Antineoplásicos Imunológicos/farmacologia , Apoptose , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/imunologia , Neoplasias da Mama/metabolismo , Proliferação de Células , Feminino , Humanos , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Macrófagos/metabolismo , Camundongos , Camundongos Nus , Microvasos/efeitos dos fármacos , Microvasos/metabolismo , Células Mieloides/efeitos dos fármacos , Células Mieloides/metabolismo , Receptor ErbB-2/imunologia , Receptor ErbB-2/metabolismo , Células Tumorais Cultivadas , Microambiente Tumoral , Ensaios Antitumorais Modelo de Xenoenxerto
11.
J Immunother Precis Oncol ; 3(1): 3-15, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35756177

RESUMO

Immunotherapy is a rapidly evolving treatment paradigm that holds promise to provide long-lasting survival benefits for patients with cancer. This promise, however, remains unfulfilled for the majority of patients with gastrointestinal (GI) cancers, as significant limitations in efficacy exist with immune checkpoint inhibitors (ICIs) in this disease group. A plethora of novel combination treatment strategies are currently being investigated in various clinical trials to make them more efficacious as our understanding of molecular mechanisms mediating resistance to immunotherapy advances. In this article, we summarize the current status of immune checkpoint blockade in GI cancers and discuss the biological rationales that underlie the emerging treatment strategies being tested in ongoing clinical trials in combination with ICIs. We also highlight the promising early results from these strategies and provide future perspectives on enhancing response to immunotherapy for patients with GI cancers.

12.
Nat Biotechnol ; 36(8): 758-764, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30010674

RESUMO

Increased tryptophan (Trp) catabolism in the tumor microenvironment (TME) can mediate immune suppression by upregulation of interferon (IFN)-γ-inducible indoleamine 2,3-dioxygenase (IDO1) and/or ectopic expression of the predominantly liver-restricted enzyme tryptophan 2,3-dioxygenase (TDO). Whether these effects are due to Trp depletion in the TME or mediated by the accumulation of the IDO1 and/or TDO (hereafter referred to as IDO1/TDO) product kynurenine (Kyn) remains controversial. Here we show that administration of a pharmacologically optimized enzyme (PEGylated kynureninase; hereafter referred to as PEG-KYNase) that degrades Kyn into immunologically inert, nontoxic and readily cleared metabolites inhibits tumor growth. Enzyme treatment was associated with a marked increase in the tumor infiltration and proliferation of polyfunctional CD8+ lymphocytes. We show that PEG-KYNase administration had substantial therapeutic effects when combined with approved checkpoint inhibitors or with a cancer vaccine for the treatment of large B16-F10 melanoma, 4T1 breast carcinoma or CT26 colon carcinoma tumors. PEG-KYNase mediated prolonged depletion of Kyn in the TME and reversed the modulatory effects of IDO1/TDO upregulation in the TME.


Assuntos
Adjuvantes Imunológicos/uso terapêutico , Hidrolases/uso terapêutico , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Cinurenina/metabolismo , Neoplasias/tratamento farmacológico , Animais , Vacinas Anticâncer/uso terapêutico , Linhagem Celular Tumoral , Humanos , Neoplasias/enzimologia , Neoplasias/imunologia , Neoplasias/metabolismo , Microambiente Tumoral
13.
Proc Natl Acad Sci U S A ; 113(8): E1016-25, 2016 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-26862168

RESUMO

Primary T-cell acute lymphoblastic leukemia (T-ALL) cells require stromal-derived signals to survive. Although many studies have identified cell-intrinsic alterations in signaling pathways that promote T-ALL growth, the identity of endogenous stromal cells and their associated signals in the tumor microenvironment that support T-ALL remains unknown. By examining the thymic tumor microenvironments in multiple murine T-ALL models and primary patient samples, we discovered the emergence of prominent epithelial-free regions, enriched for proliferating tumor cells and dendritic cells (DCs). Systematic evaluation of the functional capacity of tumor-associated stromal cells revealed that myeloid cells, primarily DCs, are necessary and sufficient to support T-ALL survival ex vivo. DCs support T-ALL growth both in primary thymic tumors and at secondary tumor sites. To identify a molecular mechanism by which DCs support T-ALL growth, we first performed gene expression profiling, which revealed up-regulation of platelet-derived growth factor receptor beta (Pdgfrb) and insulin-like growth factor I receptor (Igf1r) on T-ALL cells, with concomitant expression of their ligands by tumor-associated DCs. Both Pdgfrb and Igf1r were activated in ex vivo T-ALL cells, and coculture with tumor-associated, but not normal thymic DCs, sustained IGF1R activation. Furthermore, IGF1R signaling was necessary for DC-mediated T-ALL survival. Collectively, these studies provide the first evidence that endogenous tumor-associated DCs supply signals driving T-ALL growth, and implicate tumor-associated DCs and their mitogenic signals as auspicious therapeutic targets.


Assuntos
Células Dendríticas/imunologia , Proteínas de Neoplasias/imunologia , Leucemia-Linfoma Linfoblástico de Células T Precursoras/imunologia , Receptores de Somatomedina/imunologia , Transdução de Sinais/imunologia , Microambiente Tumoral/imunologia , Animais , Linhagem Celular Tumoral , Sobrevivência Celular , Células Dendríticas/patologia , Feminino , Humanos , Masculino , Camundongos , Proteínas de Neoplasias/genética , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patologia , Receptor IGF Tipo 1 , Receptor beta de Fator de Crescimento Derivado de Plaquetas/genética , Receptor beta de Fator de Crescimento Derivado de Plaquetas/imunologia , Receptores de Somatomedina/genética , Transdução de Sinais/genética , Microambiente Tumoral/genética
14.
Cancer Immunol Res ; 3(5): 526-35, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25627655

RESUMO

In preclinical tumor models, αOX40 therapy is often successful at treating small tumors, but is less effective once the tumors become large. For a tumor immunotherapy to be successful to cure large tumors, it will most likely require not only an agonist to boost effector T-cell function but also inhibitors of T-cell suppression. In this study, we show that combining αOX40 antibodies with an inhibitor of the TGFß receptor (SM16) synergizes to elicit complete regression of large established MCA205 and CT26 tumors. Evaluation of tumor-infiltrating T cells showed that SM16/αOX40 dual therapy resulted in an increase in proliferating granzyme B(+) CD8 T cells, which produced higher levels of IFNγ, compared with treatment with either agent alone. We also found that the dual treatment increased pSTAT3 expression in both CD4 and CD8 T cells isolated from tumors. Because others have published that STAT3 signaling is detrimental to T-cell function within the tumor microenvironment, we explored whether deletion of STAT3 in OX40-expressing cells would affect this potent combination therapy. Surprisingly, we found that deletion of STAT3 in OX40-expressing cells decreased the efficacy of this combination therapy, showing that the full therapeutic potential of this treatment depends on STAT3 signaling, most likely in the T cells of tumor-bearing mice.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias/metabolismo , Receptores OX40/antagonistas & inibidores , Receptores de Fatores de Crescimento Transformadores beta/antagonistas & inibidores , Fator de Transcrição STAT3/metabolismo , Animais , Anticorpos Monoclonais/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Compostos Azabicíclicos/administração & dosagem , Linhagem Celular Tumoral , Feminino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Receptores OX40/imunologia , Transdução de Sinais
15.
Eur J Immunol ; 42(7): 1893-905, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22585674

RESUMO

Surface expression of the IL-2 receptor α-chain (CD25) has been used to discriminate between CD4(+) CD25(HI) FOXP3(+) regulatory T (Treg) cells and CD4(+) CD25(NEG) FOXP3(-) non-Treg cells. However, this study reports that the majority of resting human memory CD4(+) FOXP3(-) T cells expresses intermediate levels of CD25 and that CD25 expression can be used to delineate a functionally distinct memory subpopulation. The CD25(NEG) memory T-cell population contains the vast majority of late differentiated cells that respond to antigens associated with chronic immune responses and are increased in patients with systemic lupus erythematosus (SLE). In contrast, the CD25(INT) memory T cells respond to antigens associated with recall responses, produce a greater array of cytokines, and are less dependent on costimulation for effector responses due to their expression of CD25. Lastly, compared to the CD25(NEG) and Treg-cell populations, the CD25(INT) memory population is lost to a greater degree from the blood of cancer patients treated with IL-2. Collectively, these results show that in humans, a large proportion of CD4(+) memory T cells express intermediate levels of CD25, and this CD25(INT) FOXP3(-) subset is a functionally distinct memory population that is uniquely affected by IL-2.


Assuntos
Fatores de Transcrição Forkhead/imunologia , Memória Imunológica/imunologia , Subunidade alfa de Receptor de Interleucina-2/imunologia , Neoplasias Renais/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Melanoma/imunologia , Linfócitos T Reguladores/imunologia , Adulto , Feminino , Citometria de Fluxo , Humanos , Imunofenotipagem/métodos , Interleucina-2/uso terapêutico , Neoplasias Renais/sangue , Neoplasias Renais/tratamento farmacológico , Lúpus Eritematoso Sistêmico/sangue , Masculino , Melanoma/sangue , Melanoma/tratamento farmacológico , Pessoa de Meia-Idade , Adulto Jovem
16.
PLoS One ; 7(4): e34467, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22496812

RESUMO

The provision of T cell co-stimulation via members of the TNFR super-family, including OX40 (CD134) and 4-1BB (CD137), provides critical signals that promote T cell survival and differentiation. Recent studies have demonstrated that ligation of OX40 can augment T cell-mediated anti-tumor immunity in pre-clinical models and more importantly, OX40 agonists are under clinical development for cancer immunotherapy. OX40 is of particular interest as a therapeutic target as it is not expressed on naïve T cells but rather, is transiently up-regulated following TCR stimulation. Although TCR engagement is necessary for inducing OX40 expression, the downstream signals that regulate OX40 itself remain unclear. In this study, we demonstrate that OX40 expression is regulated through a TCR and common gamma chain cytokine-dependent signaling cascade that requires JAK3-mediated activation of the downstream transcription factors STAT3 and STAT5. Furthermore, combined treatment with an agonist anti-OX40 mAb and IL-2 augmented tumor immunotherapy against multiple tumor types. Dual therapy was also able to restore the function of anergic tumor-reactive CD8 T cells in mice with long-term well-established (>5 wks) tumors, leading to increased survival of the tumor-bearing hosts. Together, these data reveal the ability of TCR/common gamma chain cytokine signaling to regulate OX40 expression and demonstrate a novel means of augmenting cancer immunotherapy by providing dual anti-OX40/common gamma chain cytokine-directed therapy.


Assuntos
Imunoterapia , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Interleucina-2/uso terapêutico , Receptores OX40/fisiologia , Sarcoma Experimental/imunologia , Sarcoma Experimental/terapia , Animais , Western Blotting , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Diferenciação Celular , Citocinas/metabolismo , Quimioterapia Combinada , Feminino , Citometria de Fluxo , Janus Quinase 3/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores de Antígenos de Linfócitos T/imunologia , Receptores de Antígenos de Linfócitos T/metabolismo , Fator de Transcrição STAT3/fisiologia , Fator de Transcrição STAT5/fisiologia , Sarcoma Experimental/metabolismo , Transdução de Sinais , Linfócitos T Citotóxicos , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Células Tumorais Cultivadas
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