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2.
Cancer Res ; 84(10): 1570-1582, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38417134

RESUMEN

Clear cell renal cell carcinoma (ccRCC) incidence has risen steadily over the last decade. Elevated lipid uptake and storage is required for ccRCC cell viability. As stored cholesterol is the most abundant component in ccRCC intracellular lipid droplets, it may also play an important role in ccRCC cellular homeostasis. In support of this hypothesis, ccRCC cells acquire exogenous cholesterol through the high-density lipoprotein receptor SCARB1, inhibition or suppression of which induces apoptosis. Here, we showed that elevated expression of 3 beta-hydroxy steroid dehydrogenase type 7 (HSD3B7), which metabolizes cholesterol-derived oxysterols in the bile acid biosynthetic pathway, is also essential for ccRCC cell survival. Development of an HSD3B7 enzymatic assay and screening for small-molecule inhibitors uncovered the compound celastrol as a potent HSD3B7 inhibitor with low micromolar activity. Repressing HSD3B7 expression genetically or treating ccRCC cells with celastrol resulted in toxic oxysterol accumulation, impaired proliferation, and increased apoptosis in vitro and in vivo. These data demonstrate that bile acid synthesis regulates cholesterol homeostasis in ccRCC and identifies HSD3B7 as a plausible therapeutic target. SIGNIFICANCE: The bile acid biosynthetic enzyme HSD3B7 is essential for ccRCC cell survival and can be targeted to induce accumulation of cholesterol-derived oxysterols and apoptotic cell death.


Asunto(s)
Ácidos y Sales Biliares , Carcinoma de Células Renales , Colesterol , Homeostasis , Neoplasias Renales , Humanos , Carcinoma de Células Renales/metabolismo , Carcinoma de Células Renales/patología , Carcinoma de Células Renales/genética , Ácidos y Sales Biliares/metabolismo , Colesterol/metabolismo , Neoplasias Renales/metabolismo , Neoplasias Renales/patología , Neoplasias Renales/genética , Animales , Ratones , Triterpenos Pentacíclicos , Línea Celular Tumoral , Apoptosis , Proliferación Celular , Triterpenos/farmacología , Carcinogénesis/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto
3.
Nat Cancer ; 5(1): 131-146, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38168934

RESUMEN

Availability of the essential amino acid methionine affects cellular metabolism and growth, and dietary methionine restriction has been implicated as a cancer therapeutic strategy. Nevertheless, how liver cancer cells respond to methionine deprivation and underlying mechanisms remain unclear. Here we find that human liver cancer cells undergo irreversible cell cycle arrest upon methionine deprivation in vitro. Blocking methionine adenosyl transferase 2A (MAT2A)-dependent methionine catabolism induces cell cycle arrest and DNA damage in liver cancer cells, resulting in cellular senescence. A pharmacological screen further identified GSK3 inhibitors as senolytics that selectively kill MAT2A-inhibited senescent liver cancer cells. Importantly, combined treatment with MAT2A and GSK3 inhibitors therapeutically blunts liver tumor growth in vitro and in vivo across multiple models. Together, methionine catabolism is essential for liver tumor growth, and its inhibition can be exploited as an improved pro-senescence strategy for combination with senolytic agents to treat liver cancer.


Asunto(s)
Glucógeno Sintasa Quinasa 3 , Neoplasias Hepáticas , Humanos , S-Adenosilmetionina/metabolismo , S-Adenosilmetionina/farmacología , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/genética , Metionina/farmacología , Metionina Adenosiltransferasa/metabolismo
4.
bioRxiv ; 2023 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-37745397

RESUMEN

Nuclear speckles are membrane-less bodies within the cell nucleus enriched in RNA biogenesis, processing, and export factors. In this study we investigated speckle phenotype variation in human cancer, finding a reproducible speckle signature, based on RNA expression of speckle-resident proteins, across >20 cancer types. Of these, clear cell renal cell carcinoma (ccRCC) exhibited a clear correlation between the presence of this speckle expression signature, imaging-based speckle phenotype, and clinical outcomes. ccRCC is typified by hyperactivation of the HIF-2α transcription factor, and we demonstrate here that HIF-2α drives physical association of a select subset of its target genes with nuclear speckles. Disruption of HIF-2α-driven speckle association via deletion of its speckle targeting motifs (STMs)-defined in this study-led to defective induction of speckle-associating HIF-2α target genes without impacting non-speckle-associating HIF-2α target genes. We further identify the RNA export complex, TREX, as being specifically altered in speckle signature, and knockdown of key TREX component, ALYREF, also compromises speckle-associated gene expression. By integrating tissue culture functional studies with tumor genomic and imaging analysis, we show that HIF-2α gene regulatory programs are impacted by specific manipulation of speckle phenotype and by abrogation of speckle targeting abilities of HIF-2α. These findings suggest that, in ccRCC, a key biological function of nuclear speckles is to modulate expression of a specific subset of HIF-2α-regulated target genes that, in turn, influence patient outcomes. We also identify STMs in other transcription factors, suggesting that DNA-speckle targeting may be a general mechanism of gene regulation.

5.
Front Nutr ; 10: 1111624, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37215219

RESUMEN

Introduction: Polyunsaturated fatty acids (PUFA) and highly unsaturated fatty acid (HUFA) synthetic products and their signaling metabolites play vital roles in immunity, inflammation, and brain development/function. Frequency differences of variants within the fatty acid desaturase (FADS) gene cluster affect levels of HUFAs, their biologically active products, and numerous physiological phenotypes. Fundamental questions remain regarding the impact of this genetic variation on the health of Hispanic/Latino populations. Methods: Data and biospecimens (plasma, red blood cells, buffy coat-derived DNA) from 135 participants (83.7% female) were used to assess the relationship(s) between dietary PUFA levels, a FADS haplotype tagging SNP, rs174537, and the capacity of Hispanic/Latino populations to generate HUFAs in plasma and RBC as well as its potential impact on anthropomorphic phenotypes. Results: The dietary habits of the cohort showed that participant diets contained a high ratio (9.3 ± 0.2, mean ± SEM) of linoleic acid (n-6) to alpha-linolenic acid (n-3) and also contained extremely low levels of n-3 HUFAs (eicosapentaenoic acid, EPA and docosahexaenoic acid, DHA), both features of the Modern Western Diet. Compared to African and European American cohorts, the frequency of the TT rs174537 genotype was highly enriched (53% of subjects) in this Hispanic/Latino cohort and was strongly associated with lower circulating HUFA levels. For example, plasma levels of arachidonic acid (ARA: 20:4, n-6) and EPA (20:5, n-3) were 37% and 23%, respectively, lower in the TT versus the GG genotype. HUFA biosynthetic efficiency, as determined by metabolic product to precursor ratios, was highly dependent (p < 0.0001) on the rs174537 genotype (GG > GT > TT) for both circulating n-6 and n-3 HUFAs. In contrast, the RBC Omega-3 Index (EPA + DHA) was extremely low (2.89 ± 1.65, mean ± sd) in this population and independent of rs174537 genotype. Importantly, the rs174537 genotype was also related to female height with TT genotype participants being 4.5 cm shorter (p = 0.0001) than the GG + GT participants. Discussion: Taken together, this study illustrates that dietary PUFA + HUFA × FADS gene- interactions place a large proportion (>50%) of Hispanic/Latino populations at high risk of a deficiency in both circulating and cellular levels of n-3 HUFAs.

6.
Environ Geochem Health ; 45(12): 9477-9494, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36707498

RESUMEN

This article proposes a mathematical model to characterize phytoremediation processes in soils contaminated with heavy metals. In particular, the proposed model constructs characteristic curves for the concentrations of several metals (As, Cd, Cu, Fe, Pb, Sb, and Zn) in soils and plants based on the experimental data retrieved from several bibliographical sources comprising 305 vegetal species. The proposed model is an extension of previous models of characteristic curves in phytoremediation processes developed by Lam et al. for root measurements using the bioconcentration factor. However, the proposed model extends this approach to consider roots, as well as aerial parts and shoots of the plant, while at the same time providing a less complex mathematical formula compared to the original. The final model shows an adjusted R2 of 0.712, and all its parameters are considered statistically significant. The model may be used to assess samples from a given plant species to identify its potential as an accumulator in the context of soil phytoremediation processes. Furthermore, a simplified version of the model was constructed using an approximation to provide an easy-to-compute alternative that is valid for concentrations below 37,000 mg/kg. This simplified model shows results similar to the original model for concentrations below this threshold and it uses an adjusted factor defined as [Formula: see text] that must be compared with a threshold depending on the metal, type of measurement, and target (e.g., accumulator or hyperaccumulator). The full model construction shows that 90 out of the 305 species assessed have a potential behavior as accumulators and 10 of them as hyperaccumulators. Finally, out of the 1405 experimental measurements, 1177 were shown to be accumulators or hyperaccumulators. In particular, 85% of the results coincide with the reported values, thus validating the proposed model.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Suelo , Contaminantes del Suelo/análisis , Raíces de Plantas/química , Metales Pesados/análisis , Plantas , Biodegradación Ambiental
7.
Environ Geochem Health ; 45(12): 8867-8880, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35965294

RESUMEN

Many vegetal species can accumulate great amounts of metallic elements in their tissues. For this reason, they are called metal hyperaccumulators. An indicator of great interest in environmental sciences is the bioconcentration factor because it is recognized for establishing the potential accumulation of chemicals in organisms. Particularly in soil phytoremediation processes, it measures the capacity of a certain plant to capture metals, in terms of soil concentration. According to their behavior, four types of plants can be distinguished regarding soil concentration increase: indicator, excluder, accumulator, and hyperaccumulator. This study proposes a new model to categorize plants according to their behavior related to soil concentration increase, using several characteristic curves obtained from 1288 experimental measurements collected from different bibliographic sources. The metals analyzed were Cu, Fe, Pb, and Zn. The proposed model is obtained through linear regression and nonlinear transformations to model the expected behavior of plants in high concentration conditions. In particular, the basic equation of the model has three key components to represent the expected concentration in the plant root given the final soil concentration level, the type of species, and specific metal: a linear factor that determines the growth for low concentration values, an exponential factor that determines its decrease for high concentration values, and a logarithmic factor that limits the maximum value that can be reached in practice and influences the decay for high concentration values. After fitting the experimental data using linear regression, the proposed model has a 0.084 R2 determination coefficient and all of its parameters are considered significant. Furthermore, it shows that 60 of the 257 species assessed behave as accumulators and 10 of them as hyperaccumulators. The main contribution of this model is its ability to handle soils with high concentrations, where it would be hard for plants to achieve concentrations similar to or higher than the substrate containing them. Thus, the conventional criterion of the bioconcentration factor would incorrectly categorize a plant as an excluder. In contrast, this new model allows assessing plant effectiveness in a phytoremediation process of highly concentrated affected sites, such as mine tailings.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Suelo , Contaminantes del Suelo/análisis , Metales Pesados/análisis , Plantas , Biodegradación Ambiental
8.
BMJ Open ; 12(11): e066851, 2022 11 22.
Artículo en Inglés | MEDLINE | ID: mdl-36414301

RESUMEN

OBJECTIVES: We aim to establish daily risk estimates of the relationships between grass, tree and weed pollen and asthma health outcomes. DESIGN: Time series regression analysis of exposure and health outcomes using interaction by month to determine risk estimates all year round. SETTING: Metropolitan Adelaide, South Australia. PARTICIPANTS: Health outcomes for asthma are based on 15 years of hospital admissions, 13 years emergency presentations and ambulance callouts. In adults (≥18 years), there were 10 381 hospitalisations, 26 098 emergency department (ED) presentations and 11 799 ambulance callouts and in children (0-17 years), 22 114, 39 813 and 3774, respectively. OUTCOME MEASURES: The cumulative effect of 7 day lags was calculated as the sum of the coefficients and reported as incidence rate ratio (IRR) related to an increase in 10 grains of pollen/m3. RESULTS: In relation to grass pollen, children and adults were disparate in their timing of health effects. Asthma outcomes in children were positively related to grass pollen in May, and for adults in October. Positive associations with weed pollen in children was seen from February to May across all health outcomes. For adults, weed pollen-related health outcomes were restricted to February. Adults were not affected by tree pollen, while children's asthma morbidity was associated with tree pollen in August and September. In children, IRRs ranged from 1.14 (95% CI 1.06 to 1.21) for ED presentations for tree pollen in August to 1.98 (95% CI 1.06 to 3.72) for weed pollen in February. In adults, IRRs ranged from 1.28 (95% CI 1.01 to 1.62) for weed pollen in February to 1.31 (95% CI 1.08 to 1.57) for grass pollen in October. CONCLUSION: Monthly risk assessment indicated that most pollen-related asthma health outcomes in children occur in the colder part of the year, while adults are affected in the warm season. The findings indicate a need for year-round pollen monitoring and related health campaigns to provide effective public health prevention.


Asunto(s)
Asma , Rinitis Alérgica Estacional , Niño , Adulto , Humanos , Poaceae , Árboles , Australia del Sur/epidemiología , Factores de Tiempo , Polen/efectos adversos , Asma/epidemiología , Asma/etiología , Análisis de Regresión , Evaluación de Resultado en la Atención de Salud
9.
Cancer Metab ; 9(1): 40, 2021 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-34861885

RESUMEN

BACKGROUND: Kidney cancer is a common adult malignancy in the USA. Clear cell renal cell carcinoma (ccRCC), the predominant subtype of kidney cancer, is characterized by widespread metabolic changes. Urea metabolism is one such altered pathway in ccRCC. The aim of this study was to elucidate the contributions of urea cycle enzymes, argininosuccinate synthase 1 (ASS1), and argininosuccinate lyase (ASL) towards ccRCC progression. METHODS: We employed a combination of computational, genetic, and metabolomic tools along with in vivo animal models to establish a tumor-suppressive role for ASS1 and ASL in ccRCC. RESULTS: We show that the mRNA and protein expression of urea cycle enzymes ASS1 and ASL are reduced in ccRCC tumors when compared to the normal kidney. Furthermore, the loss of ASL in HK-2 cells (immortalized renal epithelial cells) promotes growth in 2D and 3D growth assays, while combined re-expression of ASS1 and ASL in ccRCC cell lines suppresses growth in 2D, 3D, and in vivo xenograft models. We establish that this suppression is dependent on their enzymatic activity. Finally, we demonstrate that conservation of cellular aspartate, regulation of nitric oxide synthesis, and pyrimidine production play pivotal roles in ASS1+ASL-mediated growth suppression in ccRCC. CONCLUSIONS: ccRCC tumors downregulate the components of the urea cycle including the enzymes argininosuccinate synthase 1 (ASS1) and argininosuccinate lyase (ASL). These cytosolic enzymes lie at a critical metabolic hub in the cell and are involved in aspartate catabolism and arginine and nitric oxide biosynthesis. Loss of ASS1 and ASL helps cells redirect aspartate towards pyrimidine synthesis and support enhanced proliferation. Additionally, reduced levels of ASS1 and ASL might help regulate nitric oxide (NO) generation and mitigate its cytotoxic effects. Overall, our work adds to the understanding of urea cycle enzymes in a context-independent of ureagenesis, their role in ccRCC progression, and uncovers novel potential metabolic vulnerabilities in ccRCC.

10.
Cancer Discov ; 11(12): 3106-3125, 2021 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-34244212

RESUMEN

Clear cell renal cell carcinoma (ccRCC) is characterized by large intracellular lipid droplets containing free and esterified cholesterol; however, the functional significance of cholesterol accumulation in ccRCC cells is unknown. We demonstrate that, surprisingly, genes encoding cholesterol biosynthetic enzymes are repressed in ccRCC, suggesting a dependency on exogenous cholesterol. Mendelian randomization analyses based on 31,000 individuals indicate a causal link between elevated circulating high-density lipoprotein (HDL) cholesterol and ccRCC risk. Depriving ccRCC cells of either cholesterol or HDL compromises proliferation and survival in vitro and tumor growth in vivo; in contrast, elevated dietary cholesterol promotes tumor growth. Scavenger Receptor B1 (SCARB1) is uniquely required for cholesterol import, and inhibiting SCARB1 is sufficient to cause ccRCC cell-cycle arrest, apoptosis, elevated intracellular reactive oxygen species levels, and decreased PI3K/AKT signaling. Collectively, we reveal a cholesterol dependency in ccRCC and implicate SCARB1 as a novel therapeutic target for treating kidney cancer. SIGNIFICANCE: We demonstrate that ccRCC cells are auxotrophic for exogenous cholesterol to maintain PI3K/AKT signaling pathway and ROS homeostasis. Blocking cholesterol import through the HDL transporter SCARB1 compromises ccRCC cell survival and tumor growth, suggesting a novel pharmacologic target for this disease. This article is highlighted in the In This Issue feature, p. 2945.


Asunto(s)
Carcinoma de Células Renales , Neoplasias Renales , Carcinoma de Células Renales/patología , Línea Celular Tumoral , Proliferación Celular/genética , Colesterol/uso terapéutico , Humanos , Neoplasias Renales/patología , Fosfatidilinositol 3-Quinasas/metabolismo
11.
Nat Cell Biol ; 22(6): 728-739, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32367049

RESUMEN

The crosstalk between deregulated hepatocyte metabolism and cells within the tumour microenvironment, as well as the consequent effects on liver tumorigenesis, are not completely understood. We show here that hepatocyte-specific loss of the gluconeogenic enzyme fructose 1,6-bisphosphatase 1 (FBP1) disrupts liver metabolic homeostasis and promotes tumour progression. FBP1 is universally silenced in both human and murine liver tumours. Hepatocyte-specific Fbp1 deletion results in steatosis, concomitant with activation and senescence of hepatic stellate cells (HSCs), exhibiting a senescence-associated secretory phenotype. Depleting senescent HSCs by 'senolytic' treatment with dasatinib/quercetin or ABT-263 inhibits tumour progression. We further demonstrate that FBP1-deficient hepatocytes promote HSC activation by releasing HMGB1; blocking its release with the small molecule inflachromene limits FBP1-dependent HSC activation, the subsequent development of the senescence-associated secretory phenotype and tumour progression. Collectively, these findings provide genetic evidence for FBP1 as a metabolic tumour suppressor in liver cancer and establish a critical crosstalk between hepatocyte metabolism and HSC senescence that promotes tumour growth.


Asunto(s)
Carcinogénesis/patología , Proliferación Celular , Senescencia Celular , Fructosa-Bifosfatasa/fisiología , Regulación Neoplásica de la Expresión Génica , Células Estrelladas Hepáticas/patología , Neoplasias Hepáticas/patología , Animales , Carcinogénesis/metabolismo , Femenino , Células Estrelladas Hepáticas/metabolismo , Humanos , Neoplasias Hepáticas/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Microambiente Tumoral , Ensayos Antitumor por Modelo de Xenoinjerto
13.
Cell Metab ; 31(1): 174-188.e7, 2020 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-31761563

RESUMEN

The remarkable cellular and genetic heterogeneity of soft tissue sarcomas (STSs) limits the clinical benefit of targeted therapies. Here, we show that expression of the gluconeogenic isozyme fructose-1,6-bisphosphatase 2 (FBP2) is silenced in a broad spectrum of sarcoma subtypes, revealing an apparent common metabolic feature shared by diverse STSs. Enforced FBP2 expression inhibits sarcoma cell and tumor growth through two distinct mechanisms. First, cytosolic FBP2 antagonizes elevated glycolysis associated with the "Warburg effect," thereby inhibiting sarcoma cell proliferation. Second, nuclear-localized FBP2 restrains mitochondrial biogenesis and respiration in a catalytic-activity-independent manner by inhibiting the expression of nuclear respiratory factor and mitochondrial transcription factor A (TFAM). Specifically, nuclear FBP2 colocalizes with the c-Myc transcription factor at the TFAM locus and represses c-Myc-dependent TFAM expression. This unique dual function of FBP2 provides a rationale for its selective suppression in STSs, identifying a potential metabolic vulnerability of this malignancy and possible therapeutic target.


Asunto(s)
Núcleo Celular/metabolismo , Proliferación Celular/genética , Fructosa-Bifosfatasa/metabolismo , Glucólisis/genética , Mitocondrias/metabolismo , Proteínas Proto-Oncogénicas c-myc/metabolismo , Sarcoma/metabolismo , Animales , Línea Celular Tumoral , Núcleo Celular/genética , Proliferación Celular/efectos de los fármacos , Ciclo del Ácido Cítrico/efectos de los fármacos , Ciclo del Ácido Cítrico/genética , Citosol/metabolismo , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Progresión de la Enfermedad , Regulación hacia Abajo , Doxiciclina/farmacología , Femenino , Fructosa-Bifosfatasa/genética , Expresión Génica , Gluconeogénesis/genética , Gluconeogénesis/fisiología , Glucólisis/efectos de los fármacos , Proteínas del Grupo de Alta Movilidad/genética , Proteínas del Grupo de Alta Movilidad/metabolismo , Humanos , Inmunohistoquímica , Ratones , Microscopía Electrónica de Transmisión , Mitocondrias/enzimología , Mitocondrias/genética , Mitocondrias/ultraestructura , Biogénesis de Organelos , Proteínas Proto-Oncogénicas c-myc/antagonistas & inhibidores , Sarcoma/enzimología , Sarcoma/genética , Ensayos Antitumor por Modelo de Xenoinjerto
14.
Cell Metab ; 27(6): 1263-1280.e6, 2018 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-29754953

RESUMEN

Kidney cancer, one of the ten most prevalent malignancies in the world, has exhibited increased incidence over the last decade. The most common subtype is "clear cell" renal cell carcinoma (ccRCC), which features consistent metabolic abnormalities, such as highly elevated glycogen and lipid deposition. By integrating metabolomics, genomic, and transcriptomic data, we determined that enzymes in multiple metabolic pathways are universally depleted in human ccRCC tumors, which are otherwise genetically heterogeneous. Notably, the expression of key urea cycle enzymes, including arginase 2 (ARG2) and argininosuccinate synthase 1 (ASS1), is strongly repressed in ccRCC. Reduced ARG2 activity promotes ccRCC tumor growth through at least two distinct mechanisms: conserving the critical biosynthetic cofactor pyridoxal phosphate and avoiding toxic polyamine accumulation. Pharmacological approaches to restore urea cycle enzyme expression would greatly expand treatment strategies for ccRCC patients, where current therapies only benefit a subset of those afflicted with renal cancer.


Asunto(s)
Arginasa/metabolismo , Carcinoma de Células Renales/patología , Neoplasias Renales/patología , Poliaminas/metabolismo , Animales , Arginasa/genética , Argininosuccinato Sintasa/metabolismo , Carcinoma de Células Renales/tratamiento farmacológico , Carcinoma de Células Renales/enzimología , Línea Celular Tumoral , Perfilación de la Expresión Génica , Xenoinjertos , Humanos , Neoplasias Renales/tratamiento farmacológico , Neoplasias Renales/enzimología , Ratones , Ratones Desnudos , Fosfato de Piridoxal/metabolismo , Urea/metabolismo
15.
JCI Insight ; 3(7)2018 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-29618658

RESUMEN

Pancreatic ductal adenocarcinoma (PDA) is characterized by its highly immunosuppressive tumor microenvironment (TME) that limits T cell infiltration and induces T cell hypofunction. Mesothelin-redirected chimeric antigen receptor T cell (meso-CAR T cell) therapy has shown some efficacy in clinical trials but antitumor efficacy remains modest. We hypothesized that combined meso-CAR T cells with an oncolytic adenovirus expressing TNF-α and IL-2 (Ad5/3-E2F-D24-TNFa-IRES-IL2, or OAd-TNFa-IL2) would improve efficacy. OAd-TNFa-IL2 enhanced the antitumor efficacy of meso-CAR T cells in human-PDA-xenograft immunodeficient mice and efficacy was associated with robustly increased tumor-infiltrating lymphocytes (TILs), enhanced and prolonged T cell function. Mice treated with parental OAd combined with meso-CAR T developed tumor metastasis to the lungs even if primary tumors were controlled. However, no mice treated with combined OAd-TNFa-IL2 and meso-CAR T died of tumor metastasis. We also evaluated this approach in a syngeneic mouse tumor model by combining adenovirus expressing murine TNF-α and IL-2 (Ad-mTNFa-mIL2) and mouse CAR T cells. This approach induced significant tumor regression in mice engrafted with highly aggressive and immunosuppressive PDA tumors. Ad-mTNFa-mIL2 increased both CAR T cell and host T cell infiltration to the tumor and altered host tumor immune status with M1 polarization of macrophages and increased dendritic cell maturation. These findings indicate that combining cytokine-armed oncolytic adenovirus to enhance the efficacy of CAR T cell therapy is a promising approach to overcome the immunosuppressive TME for the treatment of PDA.


Asunto(s)
Carcinoma Ductal Pancreático/terapia , Proteínas Ligadas a GPI/inmunología , Inmunoterapia Adoptiva/métodos , Viroterapia Oncolítica/métodos , Neoplasias Pancreáticas/terapia , Adenoviridae/inmunología , Animales , Carcinoma Ductal Pancreático/inmunología , Línea Celular Tumoral , Terapia Combinada/métodos , Humanos , Linfocitos Infiltrantes de Tumor/inmunología , Mesotelina , Ratones , Virus Oncolíticos/inmunología , Neoplasias Pancreáticas/inmunología , Receptores Quiméricos de Antígenos/inmunología , Linfocitos T/inmunología , Linfocitos T/trasplante , Microambiente Tumoral/inmunología , Ensayos Antitumor por Modelo de Xenoinjerto
16.
JCI Insight ; 3(1)2018 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-29321369

RESUMEN

Successful tumor eradication by chimeric antigen receptor-expressing (CAR-expressing) T lymphocytes depends on CAR T cell persistence and effector function. We hypothesized that CD4+ and CD8+ T cells may exhibit distinct persistence and effector phenotypes, depending on the identity of specific intracellular signaling domains (ICDs) used to generate the CAR. First, we demonstrate that the ICOS ICD dramatically enhanced the in vivo persistence of CAR-expressing CD4+ T cells that, in turn, increased the persistence of CD8+ T cells expressing either CD28- or 4-1BB-based CARs. These data indicate that persistence of CD8+ T cells was highly dependent on a helper effect provided by the ICD used to redirect CD4+ T cells. Second, we discovered that combining ICOS and 4-1BB ICDs in a third-generation CAR displayed superior antitumor effects and increased persistence in vivo. Interestingly, we found that the membrane-proximal ICD displayed a dominant effect over the distal domain in third-generation CARs. The optimal antitumor and persistence benefits observed in third-generation ICOSBBz CAR T cells required the ICOS ICD to be positioned proximal to the cell membrane and linked to the ICOS transmembrane domain. Thus, CARs with ICOS and 4-1BB ICD demonstrate increased efficacy in solid tumor models over our current 4-1BB-based CAR and are promising therapeutics for clinical testing.


Asunto(s)
Ligando 4-1BB/metabolismo , Proteína Coestimuladora de Linfocitos T Inducibles/metabolismo , Receptores Quiméricos de Antígenos/metabolismo , Linfocitos T/inmunología , Adenocarcinoma , Animales , Antineoplásicos/farmacología , Antígenos CD28/metabolismo , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos , Línea Celular Tumoral , Membrana Celular , Humanos , Neoplasias Pulmonares , Ratones , Metástasis de la Neoplasia , Neoplasias Pancreáticas , Transducción de Señal , Ensayos Antitumor por Modelo de Xenoinjerto , Neoplasias Pancreáticas
17.
Langmuir ; 34(7): 2448-2454, 2018 02 20.
Artículo en Inglés | MEDLINE | ID: mdl-29356537

RESUMEN

We report investigations on the salt sensitivity of the thermoresponsive behavior of PNIPAAm brushes applying the quartz crystal microbalance coupled with spectroscopic ellipsometry technique. This approach enables a detailed study of the optical and mechanical behavior of the polymer coatings. Additional conclusions can be drawn from the difference between both techniques due to a difference in the contrast mechanism of both methods. A linear shift of the phase-transition temperature to lower temperatures with the addition of sodium chloride was found, similar to the behavior of free polymer chains in solution. The thermal hysteresis was found to be decreased by the addition of sodium chloride to the solution, hinting to the interaction of the ions with the amide groups of the polymer, whereby the formation of hydrogen bonds is hindered. The results of this study are of relevance to the application of PNIPAAm brushes in biological fluids and demonstrate the additional potential of the ion sensitivity besides the better known thermosensitivity.

18.
J Clin Invest ; 128(4): 1300-1316, 2018 04 02.
Artículo en Inglés | MEDLINE | ID: mdl-29381485

RESUMEN

Myc activation is a primary oncogenic event in many human cancers; however, these transcription factors are difficult to inhibit pharmacologically, suggesting that Myc-dependent downstream effectors may be more tractable therapeutic targets. Here, we show that Myc overexpression induces endoplasmic reticulum (ER) stress and engages the inositol-requiring enzyme 1α (IRE1α)/X-box binding protein 1 (XBP1) pathway through multiple molecular mechanisms in a variety of c-Myc- and N-Myc-dependent cancers. In particular, Myc-overexpressing cells require IRE1α/XBP1 signaling for sustained growth and survival in vitro and in vivo, dependent on elevated stearoyl-CoA-desaturase 1 (SCD1) activity. Pharmacological and genetic XBP1 inhibition induces Myc-dependent apoptosis, which is alleviated by exogenous unsaturated fatty acids. Of note, SCD1 inhibition phenocopies IRE1α RNase activity suppression in vivo. Furthermore, IRE1α inhibition enhances the cytotoxic effects of standard chemotherapy drugs used to treat c-Myc-overexpressing Burkitt's lymphoma, suggesting that inhibiting the IRE1α/XBP1 pathway is a useful general strategy for treatment of Myc-driven cancers.


Asunto(s)
Apoptosis , Linfoma de Burkitt/metabolismo , Endorribonucleasas/metabolismo , Homeostasis , Metabolismo de los Lípidos , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-myc/metabolismo , Transducción de Señal , Animales , Linfoma de Burkitt/genética , Linfoma de Burkitt/patología , Supervivencia Celular/genética , Estrés del Retículo Endoplásmico , Endorribonucleasas/genética , Femenino , Humanos , Ratones , Ratones Desnudos , Proteínas Serina-Treonina Quinasas/genética , Proteínas Proto-Oncogénicas c-myc/genética
19.
Cell Rep ; 20(13): 3025-3033, 2017 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-28954221

RESUMEN

The effects of transgenically encoded human and mouse IL-18 on T cell proliferation and its application in boosting chimeric antigen receptor (CAR) T cells are presented. Robust enhancement of proliferation of IL-18-secreting human T cells occurred in a xenograft model, and this was dependent on TCR and IL-18R signaling. IL-18 augmented IFN-γ secretion and proliferation of T cells activated by the endogenous TCR. TCR-deficient, human IL-18-expressing CD19 CAR T cells exhibited enhanced proliferation and antitumor activity in the xenograft model. Antigen-propelled activation of cytokine helper ensemble (APACHE) CAR T cells displayed inducible expression of IL-18 and enhanced antitumor immunity. In an intact mouse tumor model, CD19-IL-18 CAR T cells induced deeper B cell aplasia, significantly enhanced CAR T cell proliferation, and effectively augmented antitumor effects in mice with B16F10 melanoma. These findings point to a strategy to develop universal CAR T cells for patients with solid tumors.


Asunto(s)
Interleucina-18/metabolismo , Receptores de Antígenos de Linfocitos T/metabolismo , Animales , Proliferación Celular , Humanos , Ratones
20.
Nat Rev Cancer ; 16(10): 663-73, 2016 09 23.
Artículo en Inglés | MEDLINE | ID: mdl-27658636

RESUMEN

Oxygen availability, along with the abundance of nutrients (such as glucose, glutamine, lipids and albumin), fluctuates significantly during tumour evolution and the recruitment of blood vessels, leukocytes and reactive fibroblasts to complex tumour microenvironments. As such, hypoxia and concomitant nutrient scarcity affect large gene expression programmes, signalling pathways, diverse metabolic reactions and various stress responses. This Review summarizes our current understanding of how these adaptations are integrated in hypoxic tumour cells and their role in disease progression.


Asunto(s)
Adaptación Fisiológica , Neoplasias/metabolismo , Oxígeno/metabolismo , Humanos , Neoplasias/fisiopatología , Microambiente Tumoral
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