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AIMS/HYPOTHESIS: The islet vasculature, including its constituent islet endothelial cells, is a key contributor to the microenvironment necessary for normal beta cell health and function. In type 2 diabetes, islet amyloid polypeptide (IAPP) aggregates, forming amyloid deposits that accumulate between beta cells and islet capillaries. This process is known to be toxic to beta cells but its impact on the islet vasculature has not previously been studied. Here, we report the first characterisation of the effects of IAPP aggregation on islet endothelial cells/capillaries using cell-based and animal models. METHODS: Primary and immortalised islet endothelial cells were treated with amyloidogenic human IAPP (hIAPP) alone or in the presence of the amyloid blocker Congo Red or the Toll-like receptor (TLR) 2/4 antagonist OxPAPc. Cell viability was determined0 along with mRNA and protein levels of inflammatory markers. Islet capillary abundance, morphology and pericyte coverage were determined in pancreases from transgenic mice with beta cell expression of hIAPP using conventional and confocal microscopy. RESULTS: Aggregated hIAPP decreased endothelial cell viability in immortalised and primary islet endothelial cells (by 78% and 60%, respectively) and significantly increased expression of inflammatory markers Il6, Vcam1 and Edn1 mRNA relative to vehicle treatment in both cell types (p<0.05; n=4). Both cytotoxicity and the proinflammatory response were ameliorated by Congo Red (p<0.05; n=4); whereas TLR2/4-inhibition blocked inflammatory gene expression (p<0.05; n=6) without improving viability. Islets from high-fat-diet-fed amyloid-laden hIAPP transgenic mice also exhibited significantly increased expression of most markers of endothelial inflammation (p<0.05; n=5) along with decreased capillary density compared with non-transgenic littermates fed the same diet (p<0.01). Moreover, a 16% increase in capillary diameter was observed in amyloid-adjacent capillaries (p<0.01), accompanied by a doubling in pericyte structures positive for neuron-glial antigen 2 (p<0.001). CONCLUSIONS/INTERPRETATION: Islet endothelial cells are susceptible to hIAPP-induced cytotoxicity and exhibit a TLR2/4-dependent proinflammatory response to aggregated hIAPP. Additionally, we observed amyloid-selective effects that decreased islet capillary density, accompanied by increased capillary diameter and increased pericyte number. Together, these data demonstrate that the islet vasculature is a target of the cytotoxic and proinflammatory effects of aggregated hIAPP that likely contribute to the detrimental effects of hIAPP aggregation on beta cell function and survival in type 2 diabetes.
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Amiloidosis , Diabetes Mellitus Tipo 2 , Células Secretoras de Insulina , Islotes Pancreáticos , Amiloide/metabolismo , Amiloidosis/metabolismo , Animales , Rojo Congo/metabolismo , Rojo Congo/farmacología , Diabetes Mellitus Tipo 2/metabolismo , Células Endoteliales/metabolismo , Humanos , Células Secretoras de Insulina/metabolismo , Interleucina-6/metabolismo , Polipéptido Amiloide de los Islotes Pancreáticos/metabolismo , Islotes Pancreáticos/metabolismo , Ratones , Ratones Transgénicos , ARN Mensajero/metabolismo , Receptor Toll-Like 2/genética , Receptor Toll-Like 2/metabolismoRESUMEN
Type 2 diabetes is associated with the upregulation of neprilysin, a peptidase capable of cleaving glucoregulatory peptides such as glucagon-like peptide-1 (GLP-1). In humans, use of the neprilysin inhibitor sacubitril in combination with an angiotensin II receptor blocker was associated with increased plasma GLP-1 levels and improved glycemic control. Whether neprilysin inhibition per se is mediating these effects remains unknown. We sought to determine whether pharmacological neprilysin inhibition on its own confers beneficial effects on glycemic status and ß-cell function in a mouse model of reduced insulin secretion, and whether any such effects are dependent on GLP-1 receptor (GLP-1R) signaling. High-fat-fed male wild-type (Glp1r+/+) and GLP-1R knockout (Glp1r-/-) mice were treated with low-dose streptozotocin (STZ) to recapitulate type 2 diabetes-associated ß-cell dysfunction, or vehicle as control. Mice were continued on high-fat diet alone or supplemented with the neprilysin inhibitor sacubitril for 8 wk. At the end of the study period, ß-cell function was assessed by oral or intravenous glucose-tolerance test. Fasting and fed glucose were significantly lower in wild-type mice treated with sacubitril, although active GLP-1 levels and insulin secretion during oral glucose challenge were unchanged. In contrast, insulin secretion in response to intravenous glucose was significantly enhanced in sacubitril-treated wild-type mice, and this effect was blunted in Glp1r-/- mice. Similarly, sacubitril enhanced insulin secretion in vitro in islets from STZ-treated Glp1r+/+ but not Glp1r-/- mice. Together, our data suggest the insulinotropic effects of pharmacological neprilysin inhibition in a mouse model of ß-cell dysfunction are mediated via intra-islet GLP-1R signaling.NEW & NOTEWORTHY The neprilysin inhibitor, sacubitril, improves glycemic status in a mouse model of reduced insulin secretion. Sacubitril enhances intravenous but not oral glucose-mediated insulin secretion. The increased glucose-mediated insulin secretion is GLP-1 receptor-dependent. Neprilysin inhibition does not raise postprandial circulating active GLP-1 levels.
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Diabetes Mellitus Tipo 2 , Receptor del Péptido 1 Similar al Glucagón , Secreción de Insulina , Neprilisina , Aminobutiratos , Animales , Compuestos de Bifenilo , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Péptido 1 Similar al Glucagón , Receptor del Péptido 1 Similar al Glucagón/metabolismo , Glucosa , Insulina/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Neprilisina/antagonistas & inhibidores , Neprilisina/metabolismoRESUMEN
AIMS/HYPOTHESIS: Aggregation of the beta cell secretory product human islet amyloid polypeptide (hIAPP) results in islet amyloid deposition, a pathological feature of type 2 diabetes. Amyloid formation is associated with increased levels of islet IL-1ß as well as beta cell dysfunction and death, but the mechanisms that promote amyloid deposition in situ remain unclear. We hypothesised that physiologically relevant concentrations of IL-1ß stimulate beta cell islet amyloid polypeptide (IAPP) release and promote amyloid formation. METHODS: We used a humanised mouse model of endogenous beta cell hIAPP expression to examine whether low (pg/ml) concentrations of IL-1ß promote islet amyloid formation in vitro. Amyloid-forming islets were cultured for 48 h in the presence or absence of IL-1ß with or without an IL-1ß neutralising antibody. Islet morphology was assessed by immunohistochemistry and islet mRNA expression, hormone content and release were also quantified. Cell-free thioflavin T assays were used to monitor hIAPP aggregation kinetics in the presence and absence of IL-1ß. RESULTS: Treatment with a low concentration of IL-1ß (4 pg/ml) for 48 h increased islet amyloid prevalence (93.52 ± 3.89% vs 43.83 ± 9.67% amyloid-containing islets) and amyloid severity (4.45 ± 0.82% vs 2.16 ± 0.50% amyloid area/islet area) in hIAPP-expressing mouse islets in vitro. This effect of IL-1ß was reduced when hIAPP-expressing islets were co-treated with an IL-1ß neutralising antibody. Cell-free hIAPP aggregation assays showed no effect of IL-1ß on hIAPP aggregation in vitro. Low concentration IL-1ß did not increase markers of the unfolded protein response (Atf4, Ddit3) or alter proIAPP processing enzyme gene expression (Pcsk1, Pcsk2, Cpe) in hIAPP-expressing islets. However, release of IAPP and insulin were increased over 48 h in IL-1ß-treated vs control islets (IAPP 0.409 ± 0.082 vs 0.165 ± 0.051 pmol/5 islets; insulin 87.5 ± 8.81 vs 48.3 ± 17.3 pmol/5 islets), and this effect was blocked by co-treatment with IL-1ß neutralising antibody. CONCLUSIONS/INTERPRETATION: Under amyloidogenic conditions, physiologically relevant levels of IL-1ß promote islet amyloid formation by increasing beta cell release of IAPP. Neutralisation of this effect of IL-1ß may decrease the deleterious effects of islet amyloid formation on beta cell function and survival.
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Interleucina-1beta/farmacología , Amiloidosis/tratamiento farmacológico , Animales , Humanos , Insulina/metabolismo , Células Secretoras de Insulina/efectos de los fármacos , Células Secretoras de Insulina/metabolismo , Polipéptido Amiloide de los Islotes Pancreáticos/metabolismo , RatonesRESUMEN
A genome-wide association study (GWAS) reported that common variation in the human Niemann-Pick C1 gene (NPC1) is associated with morbid adult obesity. This study was confirmed using our BALB/cJ Npc1 mouse model, whereby heterozygous mice (Npc1+/- ) with decreased gene dosage were susceptible to weight gain when fed a high-fat diet (HFD) compared with homozygous normal mice (Npc1+/+ ) fed the same diet. The objective for our current study was to validate this Npc1 gene-diet interaction using statistical modeling with fitted growth trajectories, conduct body weight analyses for different measures, and define the physiological basis responsible for weight gain. Metabolic phenotype analysis indicated no significant difference between Npc1+/+ and Npc1+/- mice fed a HFD for food and water intake, oxygen consumption, carbon dioxide production, locomotor activity, adaptive thermogenesis, and intestinal lipid absorption. However, the livers from Npc1+/- mice had significantly increased amounts of mature sterol regulatory element-binding protein-1 (SREBP-1) and increased expression of SREBP-1 target genes that regulate glycolysis and lipogenesis with an accumulation of triacylglycerol and cholesterol. Moreover, white adipose tissue from Npc1+/- mice had significantly decreased amounts of phosphorylated hormone-sensitive lipase with decreased triacylglycerol lipolysis. Consistent with these results, cellular energy metabolism studies indicated that Npc1+/- fibroblasts had significantly increased glycolysis and lipogenesis, in addition to significantly decreased substrate (glucose and endogenous fatty acid) oxidative metabolism with an accumulation of triacylglycerol and cholesterol. In conclusion, these studies demonstrate that the Npc1 gene interacts with a HFD to promote weight gain through differential regulation of central energy metabolism pathways.
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Dieta Alta en Grasa/efectos adversos , Metabolismo Energético/genética , Interacción Gen-Ambiente , Redes y Vías Metabólicas/genética , Proteínas/fisiología , Aumento de Peso/genética , Animales , Células Cultivadas , Regulación de la Expresión Génica/genética , Péptidos y Proteínas de Señalización Intracelular , Hígado/metabolismo , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Transgénicos , Proteína Niemann-Pick C1 , Proteínas/genéticaRESUMEN
INTRODUCTION: Lymphocytic colitis and microscopic enteritis are relatively common causes of chronic diarrhea and it is characterized by an intraepithelial lymphocytic infiltrate. There have been no previous reports of coexistence between these 2 pathologies. OBJECTIVE: To describe histological and clinical characteristic in patients with coexistence of lymphocytic colitis and microscopic enteritis. MATERIAL AND METHODS: All cases with simultaneous diagnosis of lymphocytic duodenosis and lymphocytic colitis were reevaluated during lapse time 2010-2016 in hospital Daniel Carrion. The slides were reviewed by 3 pathologists and clinical information was obtained from clinical records. Expression of CD3 and CD8 was detected in 6 cases by immunohistochemical assays. RESULTS: A total of 35 patients with coexistence of lymphocytic duodenitis and lymphocytic colitis were selected of the pathology archives, 80% were females, Anemia was identified in 28.5% of patients. Blastocysitis hominis infestation was identified in 31.8%. The mean intraepithelial lymphocyte CD8 and CD3 positive was 40% in microscopic enteritis, while the mean intraepithelial lymphocyte CD3 positive was 37.2% and CD8 positive was 29.2% Additionally, lymphocytic ileitis was diagnosed in 11 of our cases. Eosinophilic colitis was diagnosed in 9 cases of lymphocytic colitis Conclusion: We found that lymphocytic colitis, microscopic enteritis and even lymphocytic ileitis can coexist in a group of patients with chronic diarrhea. These findings bring the question if this concurrence of both pathologies constituted a more generalized gastrointestinal disorder, involving both the large and the small intestines.
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Colitis Linfocítica/complicaciones , Colitis Microscópica/complicaciones , Diarrea/etiología , Adulto , Anciano , Biopsia , Infecciones por Blastocystis/complicaciones , Infecciones por Blastocystis/patología , Enfermedad Crónica , Colitis Linfocítica/patología , Colitis Microscópica/patología , Colon/patología , Estudios Transversales , Duodeno/patología , Femenino , Humanos , Ileítis/complicaciones , Ileítis/patología , Íleon/patología , Masculino , Persona de Mediana Edad , Estudios RetrospectivosRESUMEN
Multiple myeloma (MM) is the second most common hematologic malignancy. Despite recent treatment advances, it remains incurable. Here, we report that Pim2 kinase expression is highly elevated in MM cells and demonstrate that it is required for MM cell proliferation. Functional interference of Pim2 activity either by short hairpin RNAs or by a potent and selective small-molecule inhibitor leads to significant inhibition of MM cell proliferation. Pim inhibition results in a significant decrease of mammalian target of rapamycin C1 (mTOR-C1) activity, which is critical for cell proliferation. We identify TSC2, a negative regulator of mTOR-C1, as a novel Pim2 substrate and show that Pim2 directly phosphorylates TSC2 on Ser-1798 and relieves the suppression of TSC2 on mTOR-C1. These findings support Pim2 as a promising therapeutic target for MM and define a novel Pim2-TSC2-mTOR-C1 pathway that drives MM proliferation.
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Proliferación Celular , Mieloma Múltiple/patología , Proteínas Serina-Treonina Quinasas/fisiología , Proteínas Proto-Oncogénicas/fisiología , Proteínas Supresoras de Tumor/metabolismo , Animales , Antineoplásicos/farmacología , Línea Celular Tumoral , Humanos , Diana Mecanicista del Complejo 1 de la Rapamicina , Ratones , Modelos Biológicos , Mieloma Múltiple/genética , Mieloma Múltiple/metabolismo , Complejos Multiproteicos/metabolismo , Fosforilación/efectos de los fármacos , Fosforilación/genética , Piperidinas/farmacología , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Serina-Treonina Quinasas/genética , Proteínas Proto-Oncogénicas/antagonistas & inhibidores , Proteínas Proto-Oncogénicas/genética , Piridinas/farmacología , Serina-Treonina Quinasas TOR/metabolismo , Proteína 2 del Complejo de la Esclerosis Tuberosa , Carga Tumoral/efectos de los fármacos , Carga Tumoral/genética , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Some view religious fundamentalism as inclusive of fear of the world as a dangerous place. Fundamentalists are known to have extensive taboo lists, but research concerning their reactions to taboo stimuli is sparse. If fear is a basic component of fundamentalism, then reactions to taboo stimuli should be somewhat similar to common fear reactions, including subjective appraisal of discomfort, psychophysiological arousal, cognitive interference, and behavioral avoidance. The current research addressed some of these questions with three studies to examine subjective discomfort to religiously-taboo and religiously-neutral words and photographs (N = 160), physiological arousal to these same photographs (N = 129), and attentional bias on a modified Stroop test of these same words (N = 182). Although subjective appraisals of discomfort to taboo words and photographs among fundamentalists were confirmed, this research did not find that physiological responses or cognitive interference to taboo stimuli were elevated in those scoring high in religious fundamentalism.
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Cristianismo/psicología , Religión y Psicología , Tabú/psicología , Adolescente , Adulto , Análisis de Varianza , Nivel de Alerta/fisiología , Atención/fisiología , Miedo/psicología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estimulación Luminosa/métodos , Tiempo de Reacción/fisiología , Distribución por Sexo , Sudeste de Estados Unidos , Test de Stroop/estadística & datos numéricos , Estudiantes/psicología , Adulto JovenRESUMEN
The Niemann-Pick C1 (NPC1) gene is associated with human obesity. Mouse models with decreased Npc1 gene dosage are susceptible to weight gain when fed a high-fat diet, but not a low-fat diet, consistent with an Npc1 gene-diet interaction. The objectives of this study were to define regulation of the Npc1 gene and to investigate the Npc1 gene-diet interaction responsible for weight gain. The experimental design involved feeding C57BL/6J male mice a low-fat diet (with 0.00, 0.10, or 1.00% cholesterol) or a high-fat diet (with 0.02% cholesterol) until 30 wk to determine regulation of the Npc1 gene in liver. The key results showed that the Npc1 gene was downregulated by dietary fatty acids (54%, P = 0.022), but not by dietary cholesterol, through feedback inhibition of the sterol regulatory element-binding protein (SREBP) pathway. However, the dietary fatty acids secondarily increased liver cholesterol, which also inhibits the SREBP pathway. Similarly, the Npc1 gene was downregulated in peritoneal fibroblasts isolated from C57BL/6J weanling male mice not exposed to the experimental diets and incubated in media supplemented with purified oleic acid (37%, P = 0.038) but not in media supplemented with purified cholesterol. These results are important because they suggest a novel mechanism for the interaction of fatty acids with the Npc1 gene to influence energy balance and to promote weight gain. Moreover, the responsiveness of the Npc1 gene to fatty acids is consistent with studies that suggest that the encoded NPC1 protein has a physiologic role in regulating both cholesterol and fatty acid metabolism.
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Colesterol en la Dieta/farmacología , Grasas de la Dieta/farmacología , Regulación hacia Abajo/efectos de los fármacos , Hígado/efectos de los fármacos , Proteínas/metabolismo , Proteínas de Unión a los Elementos Reguladores de Esteroles/metabolismo , Alimentación Animal/análisis , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Peso Corporal , Colesterol/farmacología , Dieta , Fibroblastos/citología , Fibroblastos/efectos de los fármacos , Péptidos y Proteínas de Señalización Intracelular , Metabolismo de los Lípidos , Hígado/anatomía & histología , Hígado/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Proteína Niemann-Pick C1 , Enfermedad de Niemann-Pick Tipo C/genética , Enfermedad de Niemann-Pick Tipo C/metabolismo , Ácido Oléico/farmacología , Tamaño de los Órganos , Peritoneo/citología , Proteínas/genética , ARN Mensajero/aislamiento & purificaciónRESUMEN
Neurotrophic tyrosine receptor kinase (NTRK1/2/3) fusions are oncogenic drivers in approximately 0.3% of solid tumors. High-quality testing to identify patients with NTRK fusion-positive tumors who could benefit from tropomyosin receptor kinase inhibitors is recommended, but the current NTRK testing landscape, including next-generation sequencing (NGS), is fragmented and availability of assays varies widely. The analytical and clinical performance of four commonly available RNA-based NGS assays, Archer's FusionPlex Lung panel (AFL), Illumina's TruSight Oncology 500 (TSO500), Thermo Fisher's Oncomine Precision Assay and Oncomine Focus Assay (OFA), were evaluated. Experiments were conducted using contrived samples [formalin-fixed, paraffin-embedded cell lines and SeraSeq formalin-fixed, paraffin-embedded reference material], NTRK fusion-negative clinical samples, and NTRK fusion-positive clinical samples, according to local assays. Estimated limit of detection varied across the four assays: 30 to 620 fusion copies for AFL (cell lines), versus approximately 30 to 290 copies for TSO500 and approximately 1 to 28 copies for OFA and Oncomine Precision Assay. All assays showed 100% specificity for NTRK fusions detection, but quality control pass rate was variable (AFL, 43%; TSO500, 77%; and OFA, 83%). The NTRK fusion detection rate in quality control-validated clinical samples was 100% for all assays. This comparison of the strengths and limitations of four RNA-based NGS assays will inform physicians and pathologists regarding optimal assay selection to identify patients with NTRK fusion-positive tumors.
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Neoplasias , Proteínas de Fusión Oncogénica , Biomarcadores de Tumor , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Neoplasias/genética , Proteínas de Fusión Oncogénica/genética , OncogenesRESUMEN
Treatment of heart failure with the angiotensin receptor-neprilysin inhibitor sacubitril/valsartan improved glycemic control in individuals with type 2 diabetes. The relative contribution of neprilysin inhibition versus angiotensin II receptor antagonism to this glycemic benefit remains unknown. Thus, we sought to determine the relative effects of the neprilysin inhibitor sacubitril versus the angiotensin II receptor blocker valsartan on beta-cell function and glucose homeostasis in a mouse model of reduced first-phase insulin secretion, and whether any beneficial effects are additive/synergistic when combined in sacubitril/valsartan. High fat-fed C57BL/6J mice treated with low-dose streptozotocin (or vehicle) were followed for eight weeks on high fat diet alone or supplemented with sacubitril, valsartan or sacubitril/valsartan. Body weight and fed glucose levels were assessed weekly. At the end of the treatment period, insulin release in response to intravenous glucose, insulin sensitivity, and beta-cell mass were determined. Sacubitril and valsartan, but not sacubitril/valsartan, lowered fasting and fed glucose levels and increased insulin release in diabetic mice. None of the drugs altered insulin sensitivity or beta-cell mass, but all reduced body weight gain. Effects of the drugs on insulin release were reproduced in angiotensin II-treated islets from lean C57BL/6J mice, suggesting the insulin response to each of the drugs is due to a direct effect on islets and mechanisms therein. In summary, sacubitril and valsartan each exert beneficial insulinotropic, glycemic and weight-reducing effects in obese and/or diabetic mice when administered alone; however, when combined, mechanisms within the islet contribute to their inability to enhance insulin release.
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Antagonistas de Receptores de Angiotensina , Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Resistencia a la Insulina , Insulinas , Neprilisina , Aminobutiratos/farmacología , Antagonistas de Receptores de Angiotensina/farmacología , Animales , Compuestos de Bifenilo , Peso Corporal , Diabetes Mellitus Experimental/tratamiento farmacológico , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Glucosa , Ratones , Ratones Endogámicos C57BL , Neprilisina/farmacología , Receptores de Angiotensina , Tetrazoles/farmacología , Valsartán/farmacologíaRESUMEN
Islet endothelial cells produce paracrine factors important for islet beta-cell function and survival. Under conditions of type 2 diabetes, islet endothelial cells exhibit a dysfunctional phenotype including increased expression of genes involved in cellular adhesion and inflammation. We sought to determine whether treatment of hyperglycemia with the sodium glucose co-transporter 2 inhibitor empagliflozin, either alone or in combination with metformin, would improve markers of endothelial cell function in islets, assessed ex vivo, and if such an improvement is associated with improved insulin secretion in a mouse model of diabetes in vivo. For these studies, db/db diabetic mice and non-diabetic littermate controls were treated for 6 weeks with empagliflozin or metformin, either alone or in combination. For each treatment group, expression of genes indicative of islet endothelial dysfunction was quantified. Islet endothelial and beta-cell area was assessed by morphometry of immunochemically stained pancreas sections. Measurements of plasma glucose and insulin secretion during an intravenous glucose tolerance test were performed on vehicle and drug treated diabetic animals. We found that expression of endothelial dysfunction marker genes is markedly increased in diabetic mice. Treatment with either empagliflozin or metformin lowered expression of the dysfunction marker genes ex vivo, which correlated with improved glycemic control, and increased insulin release in vivo. Empagliflozin treatment was more effective than metformin alone, with a combination of the two drugs demonstrating the greatest effects. Improving islet endothelial function through strategies such as empagliflozin/metformin treatment may provide an effective approach for improving insulin release in human type 2 diabetes.
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Compuestos de Bencidrilo/uso terapéutico , Diabetes Mellitus Experimental/tratamiento farmacológico , Células Endoteliales/efectos de los fármacos , Glucósidos/uso terapéutico , Secreción de Insulina/efectos de los fármacos , Inhibidores del Cotransportador de Sodio-Glucosa 2/uso terapéutico , Animales , Compuestos de Bencidrilo/farmacología , Glucemia/efectos de los fármacos , Evaluación Preclínica de Medicamentos , Quimioterapia Combinada , Glucósidos/farmacología , Hipoglucemiantes/uso terapéutico , Islotes Pancreáticos/efectos de los fármacos , Masculino , Metformina/uso terapéutico , Ratones , Inhibidores del Cotransportador de Sodio-Glucosa 2/farmacologíaRESUMEN
Prostate cancer is the second leading cause of cancer-related death in men. Despite having a relatively lower tumor mutational burden than most tumor types, multiple gene fusions such as TMPRSS2:ERG have been characterized and linked to more aggressive disease. Individual tumor samples have been found to contain multiple fusions, and it remains unknown whether these fusions increase tumor immunogenicity. Here, we investigated the role of fusion burden on the prevalence and expression of key molecular and immune effectors in prostate cancer tissue specimens that represented the different stages of disease progression and androgen sensitivity, including hormone-sensitive and castration-resistant prostate cancer. We found that tumor fusion burden was inversely correlated with tumor mutational burden and not associated with disease stage. High fusion burden correlated with high immune infiltration, PD-L1 expression on immune cells, and immune signatures, representing activation of T cells and M1 macrophages. High fusion burden inversely correlated with immune-suppressive signatures. Our findings suggest that high tumor fusion burden may be a more appropriate biomarker than tumor mutational burden in prostate cancer, as it more closely associates with immunogenicity, and suggests that tumors with high fusion burden could be potential candidates for immunotherapeutic agents.
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Antígeno B7-H1/genética , Biomarcadores de Tumor/inmunología , Linfocitos Infiltrantes de Tumor/inmunología , Mutación , Fusión de Oncogenes , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/inmunología , Antígeno B7-H1/inmunología , Biomarcadores de Tumor/genética , Regulación Neoplásica de la Expresión Génica , Humanos , Macrófagos/inmunología , Masculino , Clasificación del Tumor , Estadificación de Neoplasias , Neoplasias de la Próstata/patología , RNA-Seq/métodosRESUMEN
Regulatory T cells (Treg) are immunosuppressive and negatively impact response to cancer immunotherapies. CREB-binding protein (CBP) and p300 are closely related acetyltransferases and transcriptional coactivators. Here, we evaluate the mechanisms by which CBP/p300 regulate Treg differentiation and the consequences of CBP/p300 loss-of-function mutations in follicular lymphoma. Transcriptional and epigenetic profiling identified a cascade of transcription factors essential for Treg differentiation. Mass spectrometry analysis showed that CBP/p300 acetylates prostacyclin synthase, which regulates Treg differentiation by altering proinflammatory cytokine secretion by T and B cells. Reduced Treg presence in tissues harboring CBP/p300 loss-of-function mutations was observed in follicular lymphoma. Our findings provide novel insights into the regulation of Treg differentiation by CBP/p300, with potential clinical implications on alteration of the immune landscape. SIGNIFICANCE: This study provides insights into the dynamic role of CBP/p300 in the differentiation of Tregs, with potential clinical implications in the alteration of the immune landscape in follicular lymphoma.
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Proteína de Unión a CREB/inmunología , Proteína p300 Asociada a E1A/inmunología , Linfoma Folicular/inmunología , Linfocitos T Reguladores/citología , Linfocitos T Reguladores/inmunología , Acetilación , Linfocitos T CD4-Positivos/efectos de los fármacos , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/metabolismo , Proteína de Unión a CREB/antagonistas & inhibidores , Proteína de Unión a CREB/genética , Diferenciación Celular/fisiología , Regulación hacia Abajo , Proteína p300 Asociada a E1A/antagonistas & inhibidores , Proteína p300 Asociada a E1A/genética , Histonas/metabolismo , Humanos , Linfoma Folicular/genética , Linfoma Folicular/metabolismo , Linfoma Folicular/patología , Mutación , Pirazoles/farmacología , Piridinas/farmacología , Linfocitos T Reguladores/efectos de los fármacos , Linfocitos T Reguladores/metabolismo , Transcripción Genética , TranscriptomaRESUMEN
A large number of genome-wide association studies, transferability studies, and candidate gene studies performed in diverse populations around the world have identified gene variants that are associated with common human obesity. The mounting evidence suggests that these obesity gene variants interact with multiple environmental factors and increase susceptibility to this complex metabolic disease. The objective of this review article is to provide concise and updated information on energy balance, heritability of body weight, origins of gene variants, and gene-nutrient interactions in relation to human obesity. It is proposed that knowledge of these related topics will provide valuable insight for future preventative lifestyle intervention using targeted nutritional and medicinal therapies.
RESUMEN
It is generally accepted that the selection of gene variants during human evolution optimized energy metabolism that now interacts with our obesogenic environment to increase the prevalence of obesity. The purpose of this study was to perform a global evolutionary and metabolic analysis of human obesity gene risk variants (110 human obesity genes with 127 nearest gene risk variants) identified using genome-wide association studies (GWAS) to enhance our knowledge of early and late genotypes. As a result of determining the mean frequency of these obesity gene risk variants in 13 available populations from around the world our results provide evidence for the early selection of ancestral risk variants (defined as selection before migration from Africa) and late selection of derived risk variants (defined as selection after migration from Africa). Our results also provide novel information for association of these obesity genes or encoded proteins with diverse metabolic pathways and other human diseases. The overall results indicate a significant differential evolutionary pattern for the selection of obesity gene ancestral and derived risk variants proposed to optimize energy metabolism in varying global environments and complex association with metabolic pathways and other human diseases. These results are consistent with obesity genes that encode proteins possessing a fundamental role in maintaining energy metabolism and survival during the course of human evolution.
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Evolución Molecular , Predisposición Genética a la Enfermedad , Genoma Humano , Redes y Vías Metabólicas , Obesidad/genética , Polimorfismo Genético , HumanosRESUMEN
OBJECTIVE: Genome-wide association studies have identified single-nucleotide polymorphisms (SNPs) that increase the risk of developing non-alcoholic fatty liver disease (NAFLD). One purpose of this study was to determine the frequencies of NAFLD susceptibility SNPs in a non-Hispanic white and Hispanic population who attended a clinic in northeast Albuquerque, NM. Another goal was to determine associations with selected indicators in this New Mexican population. METHODS: This cohort study involving 168 volunteer subjects in the NM population (88 non-Hispanic whites, 63 Hispanics, 4 Native Americans, 11 Asian Americans, 2 unreported ethnicity). Eight SNPs within 6 NAFLD susceptibility genes including PNPLA3 (rs738409), LYPLAL1 (rs12137855), APOC3 (rs2854116, rs2854117), GCKR (rs780094, rs741038), FABP2 (rs1799883), PEMT (rs7946) were analyzed by genotyping using the TaqMan genotyping assay (Applied Biosystems, Foster City, CA). Statistical analyses were carried out using statistical package SAS 9.3. RESULTS: The NAFLD allele frequencies were similar in non-Hispanic whites and Hispanics except for PNPLA3 (rs738409), FABP2 (rs1799883), and PEMT (rs7946). Eight SNPs in 5 NAFLD susceptibility genes were significantly associated OR marginally associated with selected indicators for NAFLD, metabolic syndrome, overweight, obesity, insulin resistance, type 2 diabetes, hypertension, dyslipidemia. No SNPs were significantly associated with the same indicator in both the non-Hispanic white and Hispanic groups. CONCLUSIONS: In this population of non-Hispanic whites and Hispanics, there were only heterozygotes for the APOC3 derived alle le whereas for all other genes tested, both heterozygotes and homozygotes were found. Associations of alleles with indicators of chronic disease were different in non-Hispanic whites compared to Hispanics.
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A genome-wide association study (GWAS) and subsequent replication studies in diverse ethnic groups indicate that common Niemann-Pick C1 gene (NPC1) polymorphisms are associated with morbid-adult obesity or diabetes independent of body weight. The objectives for this prospective cross-sectional study were to determine allele frequencies for NPC1 polymorphisms (644A>G, 1926C>G, 2572A>G, and 3797G>A) and association with metabolic disease phenotypes in an ethnically diverse New Mexican obstetric population. Allele frequencies for 1926C>G, 2572A>G, and 3797G>A were significantly different between race/ethnic groups (non-Hispanic white, Hispanic, and Native American). The results also indicated a significant pairwise linkage-disequilibrium between each of the four NPC1 polymorphisms in race/ethnic groups. Moreover, the derived and major allele for 1926C>G was associated (OR 2.11, 95% CI 1.10-3.96, P = 0.022) with increased risk for maternal prepregnancy overweight (BMI 25.0-29.9kg/m2) while the ancestral and major allele for 2572A>G was associated (OR 4.68, 95% CI 1.23-17.8, P = 0.024) with increased risk for gestational diabetes in non-Hispanic whites, but not Hispanics or Native Americans. In summary, this is the first transferability study to investigate common NPC1 polymorphisms in a multiethnic population and demonstrate a differential association with increased risk for maternal prepregnancy overweight and gestational diabetes.
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Activating mutations in the KRAS oncogene occur in approximately 90% of pancreatic cancers, resulting in aberrant activation of the MAPK and the PI3K pathways, driving malignant progression. Significant efforts to develop targeted inhibitors of nodes within these pathways are underway and several are currently in clinical trials for patients with KRAS-mutant tumors, including patients with pancreatic cancer. To model MEK and PI3K inhibition in late-stage pancreatic cancer, we conducted preclinical trials with a mutant Kras-driven genetically engineered mouse model that faithfully recapitulates human pancreatic ductal adenocarcinoma development. Treatment of advanced disease with either a MEK (GDC-0973) or PI3K inhibitor (GDC-0941) alone showed modest tumor growth inhibition and did not significantly enhance overall survival. However, combination of the two agents resulted in a significant survival advantage as compared with control tumor-bearing mice. To model the clinical scenario, we also evaluated the combination of these targeted agents with gemcitabine, the current standard-of-care chemotherapy for pancreatic cancer. The addition of MEK or PI3K inhibition to gemcitabine, or the triple combination regimen, incrementally enhanced overall survival as compared with gemcitabine alone. These results are reminiscent of the survival advantage conferred in this model and in patients by the combination of gemcitabine and erlotinib, an approved therapeutic regimen for advanced nonresectable pancreatic cancer. Taken together, these data indicate that inhibition of MEK and PI3K alone or in combination with chemotherapy do not confer a dramatic improvement as compared with currently available therapies for patients with pancreatic cancer.
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Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Carcinoma Ductal Pancreático/tratamiento farmacológico , Desoxicitidina/análogos & derivados , MAP Quinasa Quinasa 1/antagonistas & inhibidores , Neoplasias Pancreáticas/tratamiento farmacológico , Inhibidores de las Quinasa Fosfoinosítidos-3 , Inhibidores de Proteínas Quinasas/administración & dosificación , Animales , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Azetidinas/administración & dosificación , Azetidinas/farmacología , Carcinoma Ductal Pancreático/genética , Línea Celular Tumoral , Desoxicitidina/administración & dosificación , Desoxicitidina/farmacología , Relación Dosis-Respuesta a Droga , Humanos , Indazoles/administración & dosificación , Indazoles/farmacología , Ratones , Modelos Biológicos , Mutación , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patología , Piperidinas/administración & dosificación , Piperidinas/farmacología , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Proto-Oncogénicas p21(ras)/genética , Nivel de Atención , Sulfonamidas/administración & dosificación , Sulfonamidas/farmacología , Ensayos Antitumor por Modelo de Xenoinjerto , GemcitabinaRESUMEN
Pan proviral insertion site of Moloney murine leukemia (PIM) 1, 2, and 3 kinase inhibitors have recently begun to be tested in humans to assess whether pan PIM kinase inhibition may provide benefit to cancer patients. Herein, the synthesis, in vitro activity, in vivo activity in an acute myeloid leukemia xenograft model, and preclinical profile of the potent and selective pan PIM kinase inhibitor compound 8 (PIM447) are described. Starting from the reported aminopiperidyl pan PIM kinase inhibitor compound 3, a strategy to improve the microsomal stability was pursued resulting in the identification of potent aminocyclohexyl pan PIM inhibitors with high metabolic stability. From this aminocyclohexyl series, compound 8 entered the clinic in 2012 in multiple myeloma patients and is currently in several phase 1 trials of cancer patients with hematological malignancies.
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Leucemia Mieloide Aguda/tratamiento farmacológico , Ácidos Picolínicos/uso terapéutico , Inhibidores de Proteínas Quinasas/uso terapéutico , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-pim-1/antagonistas & inhibidores , Proteínas Proto-Oncogénicas/antagonistas & inhibidores , Amidas/síntesis química , Amidas/química , Amidas/uso terapéutico , Animales , Línea Celular Tumoral , Halogenación , Humanos , Leucemia Mieloide Aguda/metabolismo , Ratones , Modelos Moleculares , Ácidos Picolínicos/síntesis química , Ácidos Picolínicos/química , Inhibidores de Proteínas Quinasas/síntesis química , Inhibidores de Proteínas Quinasas/química , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Proto-Oncogénicas c-pim-1/metabolismoRESUMEN
PURPOSE: The Council for the Professions Complementary to Medicine in Malta recently published a draft document regarding the introduction of mandatory continuing professional development (CPD) for radiographers. This study explored the attitudes and motivators of Maltese radiographers prior to the implementation of mandatory CPD in order to provide the necessary information required by management to develop CPD successfully. Concept maps are used as part of a methodology to analyse qualitative data. METHODS: All radiographers working in the National Health Service were invited to complete an anonymous web-based questionnaire. RESULTS: The study showed that participants generally had a positive attitude towards CPD but were concerned about the mandatory aspect. The participants were mostly motivated by increasing professional knowledge, updating existing qualifications, and enhancing the status of the profession as a whole. Radiographers identified several difficulties with respect to CPD participation, such as lack of funding, lack of management support, and not enough local CPD opportunities. CPD participation was also negatively influenced by family commitments. CONCLUSION: The study showed that the majority of radiographers were self-motivated to engage in CPD activities, but there were some concerns. Based on these results, the authors suggest recommendations for allaying apprehension and producing the necessary conditions for a successful mandatory CPD scheme.