RESUMEN
Neuraminidases (NEUs) also called sialidases are glycosidases which catalyze the removal of terminal sialic acid residues from glycoproteins, glycolipids, and oligosaccharides. Mammalian NEU-1 participates in regulation of cell surface receptors such as insulin receptor (IR), epithelial growth factor receptor, low-density lipoprotein receptor, and toll-like receptor 4. At the plasma membrane, NEU-1 can be associated with the elastin-binding protein and the carboxypeptidase protective protein/cathepsin A to constitute the elastin receptor complex. In this complex, NEU-1 is essential for elastogenesis, signal transduction through this receptor and for biological effects of the elastin-derived peptides on atherosclerosis, thrombosis, insulin resistance, nonalcoholic steatohepatitis, and cancers. This is why research teams are developing inhibitors targeting this sialidase. Previously, we developed interfering peptides to inhibit the dimerization and the activation of NEU-1. In this study, we investigated the effects of these peptides on IR activation in vitro and in vivo. Using cellular overexpression and endogenous expression models of NEU-1 and IR (COS-7 and HepG2 cells, respectively), we have shown that interfering peptides inhibit NEU-1 dimerization and sialidase activity which results in a reduction of IR phosphorylation. These results demonstrated that NEU-1 positively regulates IR phosphorylation and activation in our conditions. In vivo, biodistribution study showed that interfering peptides are well distributed in mice. Treatment of C57Bl/6 mice during 8 weeks with interfering peptides induces a hyperglycemic effect in our experimental conditions. Altogether, we report here that inhibition of NEU-1 sialidase activity by interfering peptides decreases IR activity in vitro and glucose homeostasis in vivo.
Asunto(s)
Neuraminidasa , Receptor de Insulina , Neuraminidasa/metabolismo , Neuraminidasa/antagonistas & inhibidores , Animales , Receptor de Insulina/metabolismo , Humanos , Ratones , Células Hep G2 , Chlorocebus aethiops , Homeostasis/efectos de los fármacos , Péptidos/farmacología , Péptidos/química , Masculino , Glucosa/metabolismo , Ratones Endogámicos C57BL , Receptores de Superficie CelularRESUMEN
Merkel cell carcinoma (MCC) is an aggressive skin cancer frequently caused by genomic integration of the Merkel cell polyomavirus (MCPyV). MCPyV-negative cases often present as combined MCCs, which represent a distinctive subset of tumors characterized by association of an MCC with a second tumor component, mostly squamous cell carcinoma. Up to now, only exceptional cases of combined MCC with neuroblastic differentiation have been reported. Herein we describe two additional combined MCCs with neuroblastic differentiation and provide comprehensive morphologic, immunohistochemical, transcriptomic, genetic and epigenetic characterization of these tumors, which both arose in elderly men and appeared as an isolated inguinal adenopathy. Microscopic examination revealed biphasic tumors combining a poorly differentiated high-grade carcinoma with a poorly differentiated neuroblastic component lacking signs of proliferation. Immunohistochemical investigation revealed keratin 20 and MCPyV T antigen (TA) in the MCC parts, while neuroblastic differentiation was confirmed in the other component in both cases. A clonal relation of the two components can be deduced from 20 and 14 shared acquired point mutations detected by whole exome analysis in both combined tumors, respectively. Spatial transcriptomics demonstrated a lower expression of stem cell marker genes such as SOX2 and MCM2 in the neuroblastic component. Interestingly, although the neuroblastic part lacked TA expression, the same genomic MCPyV integration and the same large T-truncating mutations were observed in both tumor parts. Given that neuronal transdifferentiation upon TA repression has been reported for MCC cell lines, the most likely scenario for the two combined MCC/neuroblastic tumors is that neuroblastic transdifferentiation resulted from loss of TA expression in a subset of MCC cells. Indeed, DNA methylation profiling suggests an MCC-typical cellular origin for the combined MCC/neuroblastomas. © 2024 The Author(s). The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.
Asunto(s)
Antígenos Virales de Tumores , Carcinoma de Células de Merkel , Transdiferenciación Celular , Poliomavirus de Células de Merkel , Neoplasias Cutáneas , Humanos , Carcinoma de Células de Merkel/patología , Carcinoma de Células de Merkel/virología , Carcinoma de Células de Merkel/genética , Carcinoma de Células de Merkel/metabolismo , Masculino , Neoplasias Cutáneas/patología , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/virología , Neoplasias Cutáneas/metabolismo , Antígenos Virales de Tumores/genética , Antígenos Virales de Tumores/metabolismo , Poliomavirus de Células de Merkel/genética , Puntos de Control del Ciclo Celular/genética , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Anciano de 80 o más Años , Anciano , Neoplasias Complejas y Mixtas/patología , Neoplasias Complejas y Mixtas/genética , Neoplasias Complejas y Mixtas/metabolismo , Neuroblastoma/patología , Neuroblastoma/genética , Neuroblastoma/metabolismoRESUMEN
Type 2 diabetes (T2D) constitutes a major public health problem, and despite prevention efforts, this pandemic disease is 'one of the deadliest diseases in the world. In 2022, 6.7 million T2D patients died prematurely from vascular complications. Indeed, diabetes increases the risk of myocardial infarction or stroke eightfold. The identification of the molecular actors involved in the occurrence of cardiovascular complications and their prevention are therefore major axes. Our hypothesis is that factors brought into play during physiological aging appear prematurely with diabetes progression. Our study focused on the aging of the extracellular matrix (ECM), a major element in the maintenance of vascular homeostasis. We characterized the morphological and functional aspects of aorta, with a focus on the collagen and elastic fibers of diabetic mice aged from 6 months to non-diabetic mice aged 6 months and 20 months. The comparison with the two non-diabetic models (young and old) highlighted an exacerbated activity of proteases, which could explain a disturbance in the collagen accumulation and an excessive degradation of elastic fibers. Moreover, the generation of circulating elastin-derived peptides reflects premature aging of the ECM. These extracellular elements contribute to the appearance of vascular rigidity, often the origin of pathologies such as hypertension and atherosclerosis. In conclusion, we show that diabetic mice aged 6 months present the same characteristics of ECM wear as those observed in mice aged 20 months. This accelerated aortic wall remodeling could then explain the early onset of cardiovascular diseases and, therefore, the premature death of DT2 patients.
RESUMEN
Encephalocraniocutaneous lipomatosis (ECCL) or Haberland syndrome (MIM #613001) is a rare congenital neurocutaneous disorder. It is characterized by unilateral ocular, cutaneous and central nervous system anomalies. Key clinical features include hairless fatty tissue nevus of the scalp, choristoma of the eye and intraspinal and intracerebral lipomas. We report one of the first cases diagnosed after termination of pregnancy at 35 WG, including antenatal and post-mortem imaging, complete autopsy and genetic analysis. Prenatal ultrasound and MRI of the third trimester showed multifocal spinal lesions and left lateral cerebral ventriculomegaly with cerebral atrophy. Diagnosis of ECCL was suggested at complete autopsy which revealed nevus psiloliparus of the scalp, facial hamartomas and intracranial and spinal lipomas. In addition, our case also exhibited a cardiac rhabdomyoma and a multicystic dysplastic kidney, both never reported to date in this syndrome. ECCL was confirmed by the identification of a postzygotic FGFR1 mutation. We reviewed the literature and discuss the pathogenesis of this syndrome.
Asunto(s)
Lipoma , Síndromes Neurocutáneos , Nevo , Autopsia , Oftalmopatías , Femenino , Humanos , Lipoma/diagnóstico , Lipoma/genética , Lipomatosis , Síndromes Neurocutáneos/diagnóstico , Síndromes Neurocutáneos/genética , Síndromes Neurocutáneos/patología , Embarazo , SíndromeRESUMEN
ABSTRACT: Desialylation, governed by sialidases or neuraminidases, is strongly implicated in a wide range of human disorders, and accumulative data show that inhibition of neuraminidases, such as neuraminidases 1 sialidase, may be useful for managing atherosclerosis. Several studies have reported promising effects of oseltamivir phosphate, a widely used anti-influenza sialidase inhibitor, on human cancer cells, inflammation, and insulin resistance. In this study, we evaluated the effects of oseltamivir phosphate on atherosclerosis and thrombosis and potential liver toxicity in LDLR-/- mice fed with high-fat diet. Our results showed that oseltamivir phosphate significantly decreased plasma levels of LDL cholesterol and elastin fragmentation in aorta. However, no effect was observed on both atherosclerotic plaque size in aortic roots and chemically induced thrombosis in carotid arteries. Importantly, oseltamivir phosphate administration had adverse effects on the liver of mice and significantly increased messenger RNA expression levels of F4/80, interleukin-1ß, transforming growth factor-ß1, matrix metalloproteinase-12, and collagen. Taken together, our findings suggest that oseltamivir phosphate has limited benefits on atherosclerosis and carotid thrombosis and may lead to adverse side effects on the liver with increased inflammation and fibrosis.
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Antivirales/toxicidad , Enfermedades de la Aorta/tratamiento farmacológico , Aterosclerosis/tratamiento farmacológico , Trombosis de las Arterias Carótidas/tratamiento farmacológico , Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Hígado/efectos de los fármacos , Oseltamivir/toxicidad , Receptores de LDL/deficiencia , Animales , Aorta/efectos de los fármacos , Aorta/metabolismo , Aorta/patología , Enfermedades de la Aorta/metabolismo , Enfermedades de la Aorta/patología , Aterosclerosis/metabolismo , Aterosclerosis/patología , Trombosis de las Arterias Carótidas/metabolismo , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Dieta Alta en Grasa , Modelos Animales de Enfermedad , Femenino , Hígado/metabolismo , Hígado/patología , Cirrosis Hepática/inducido químicamente , Cirrosis Hepática/metabolismo , Cirrosis Hepática/patología , Ratones Noqueados , Placa Aterosclerótica , Receptores de LDL/genética , Medición de RiesgoRESUMEN
Pulmonary embolism is a major cause of maternal morbidity during pregnancy. Beside the frequently encountered thromboembolism, trophoblastic cell embolism has also been reported in a few case reports. This phenomenon may be symptomless in physiological gestational process but is more pronounced in contexts of preeclampsia or gestational trophoblastic disease. It was exceptionally reported to be associated with death. Here, we report the case of a 15-year-old girl, who experienced dyspnea followed by cardiac arrests and disseminated intravascular coagulation. Echocardiography showed a massive proximal pulmonary embolism. Abdominal sonography revealed that she was 11 weeks pregnant. Autopsy confirmed the presence of multiple clot emboli in the proximal pulmonary arteries. Additionally, the histopathological examination showed a massive syncytiotrophoblastic embolism in the lung microcirculation. Microscopic examination of the uterus revealed an exaggerated placental site reaction. In conclusion, this exhaustive post-mortem study describes a previously unreported association between exaggerated placental site reaction and pulmonary trophoblastic embolism, with fatal issue. Forensic pathologists should be aware that a large sampling of the lungs and uterus and examination of both placenta and fetus are needed to achieve this diagnosis. This case study emphasizes the need for further work elucidating pathways of trophoblast deportation.
Asunto(s)
Placenta/fisiopatología , Complicaciones Cardiovasculares del Embarazo , Arteria Pulmonar/patología , Embolia Pulmonar/complicaciones , Tromboembolia/complicaciones , Trofoblastos/patología , Adolescente , Autopsia , Resultado Fatal , Femenino , Humanos , EmbarazoRESUMEN
The transfer of methyl-Hg (MeHg) from food is central for its effects in aquatic animals, but we still lack knowledge concerning its impact on invertebrate primary consumers. In aquatic environments, cell walls of plants are particularly recalcitrant to degradation and as such remain available as a food source for long periods. Here, the impact at the proteomic level of dietary MeHg in Gammarus fossarum was established and linked to subcellular distribution of Hg. Individuals of G. fossarum were fed with MeHg in cell wall or intracellular compartments of Elodea nuttallii. Hg concentrations in subcellular fractions were 2 to 6 times higher in animals fed with cell wall than intracellular compartments. At the higher concentrations tested, the proportion of Hg in metal-sensitive fraction increased from 30.0 ± 6.1 to 41.0 ± 5.7% for individuals fed with intracellular compartment, while biologically detoxified metal fraction increased from 30.0 ± 6.1 to 50.0 ± 2.8% when fed with cell wall compartment. Data suggested that several thresholds of proteomic response are triggered by increased bioaccumulation in each subcellular fraction in correlation with Hg exclusively bound to the metal-sensitive fraction, while the increase of biologically detoxified metal likely had a cost for fitness. Proteomics analysis supported that the different binding sites and speciation in shoots subsequently resulted in different fate and cellular toxicity pathways to consumers. Our data confirmed that Hg bound in cell walls of plants can be assimilated by G. fossarum, which is consistent with its feeding strategy, hence pointing cell walls as a significant source for Hg transfers and toxicity in primary consumers. The high accumulation of Hg in macrophytes makes them a risk for food web transfer in shallow ecosystems. The present results allowed gaining new insights into the effects and uptake mechanisms of MeHg in aquatic primary consumers.
Asunto(s)
Anfípodos , Mercurio , Compuestos de Metilmercurio , Contaminantes Químicos del Agua , Animales , Ecosistema , Cadena Alimentaria , Humanos , Proteoma , Proteómica , Contaminantes Químicos del Agua/análisisRESUMEN
Multicystic renal dysplasia is a congenital cystic anomaly of the kidney caused by abnormal metanephric differentiation with immature tubules. It is surrounded by mesenchymal collars and islands of immature mesenchyma present between the cysts. The PI3K-AKT-mTOR signaling pathway is a key regulator involved in cell growth, proliferation, motility, survival, and apoptosis. Activation of the PI3K-AKT-mTOR pathway results in the survival and proliferation of tumor cells in many cancers. The aim of this study is to analyze the topographic expression of phospho-AKT, phospho-mTOR, and phospho-70S6K in renal development and in the multicystic dysplastic kidney (MCDK). A total of 17 fetal kidneys of development age from the first to the third trimester and 13 cases of pathological kidneys with MCDK were analyzed by immunohistochemistry in order to evaluate the expression of phospho-AKT (S473), phospho-mTOR, and phospho-70S6K. Phospho-AKT and phospho-mTOR were expressed early in renal development and in an identical manner for every structure derived from the ureteric bud, such as collecting ducts and urothelium. Phospho-p70S6K was expressed early in the urothelium and in glomerular mesangial cells. Later, their expressions differed according to the needs of cell proliferation and differentiation over time by becoming more selective. In MCDK, phospho-AKT, phospho-mTOR, and phospho-70S6K have the same profile: a high cytoplasmic expression in cystic epithelium, loose mesenchyma, and primitive tubes. This study demonstrates the essential and specific role of the PI3K-AKT-mTOR pathway in the formation of cysts in multicystic renal dysplasia.
Asunto(s)
Riñón/patología , Riñón Displástico Multiquístico/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal , Diferenciación Celular , Proliferación Celular , Quistes/fisiopatología , Femenino , Humanos , Inmunohistoquímica , Riñón/citología , Riñón/metabolismo , Masculino , Riñón Displástico Multiquístico/patología , Proteínas Proto-Oncogénicas c-akt/genética , Investigación Cualitativa , Estudios Retrospectivos , Serina-Treonina Quinasas TOR/genética , Serina-Treonina Quinasas TOR/metabolismoRESUMEN
BACKGROUND: Neuroblastoma (NB) is a frequent pediatric tumor associated with poor prognosis. The disregulation of Bcl-2, an anti-apoptotic protein, is crucial for the tumoral development and chemoresistance. Autophagy is also implicated in tumor cell survival and chemoresistance. The aim of our study was to demonstrate therapeutic efficiency of GX 15-070, a pan-Bcl-2 family inhibitor, used alone and in combination with conventional drugs or with hydroxychloroquine (HCQ), an autophagy inhibitor. METHODS: Five neuroblastoma cell lines were tested for the cytotoxic activity of GX 15-070 alone or in combination with cisplatin, doxorubicin, HCQ or Z-VAD-FMK a broad-spectrum caspase inhibitor. Apoptosis and autophagy levels were studied by western-blot and FACS. Orthotopic injections were performed on NOD/LtSz-scid/IL-2Rgamma null mice that were treated with either GX 15-070 alone or in combination with HCQ. RESULTS: Synergistic cytotoxicity was observed for the drug combination in all of the 5 neuroblastoma cell lines tested, including MYCN amplified lines and in cancer stem cells. GX 15-070 significantly increased apoptosis and autophagy in neuroblastoma cells as evidenced by increased levels of the autophagy marker, LC3-II. Inhibition of autophagy by HCQ, further increased the cytotoxicity of this combinatorial treatment, suggesting that autophagy induced by these agent plays a cytoprotective role. In vivo, GX 15-070 combined with HCQ significantly decreased the growth of the tumor and the number of distant metastases. CONCLUSIONS: Based on the synergistic effect of HCQ and GX 15-070 observed in this study, the combination of these two drugs may be utilized as a new therapeutic approach for neuroblastoma.
Asunto(s)
Neoplasias de las Glándulas Suprarrenales/metabolismo , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Autofagia/efectos de los fármacos , Resistencia a Antineoplásicos/efectos de los fármacos , Neuroblastoma/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/antagonistas & inhibidores , Pirroles/farmacología , Neoplasias de las Glándulas Suprarrenales/tratamiento farmacológico , Neoplasias de las Glándulas Suprarrenales/patología , Animales , Antineoplásicos/uso terapéutico , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Sinergismo Farmacológico , Femenino , Humanos , Hidroxicloroquina/farmacología , Hidroxicloroquina/uso terapéutico , Indoles , Masculino , Ratones , Ratones Endogámicos NOD , Ratones SCID , Neuroblastoma/tratamiento farmacológico , Neuroblastoma/patología , Pirroles/uso terapéutico , Carga Tumoral/efectos de los fármacos , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
We report findings from a male fetus of 26 weeks' gestational age with severe isolated intrauterine growth restriction (IUGR). Chromosomal microarray analysis (CMA) on amniotic fluid cells revealed a 1.06-Mb duplication in 19q13.42 inherited from the healthy father. This duplication contains 34 genes including ZNF331, a gene encoding a zinc-finger protein specifically imprinted (paternally expressed) in the placenta. Study of the ZNF331 promoter by methylation-specific-multiplex ligation-dependent probe amplification showed that the duplicated allele was not methylated in the fetus unlike in the father's genome, suggesting both copies of the ZNF331 gene are expressed in the fetus. The anti-ZNF331 immunohistochemical analysis confirmed that ZNF331 was expressed at higher levels in renal and placental tissues from this fetus compared to controls. Interestingly, ZNF331 expression levels in the placenta have previously been reported to inversely correlate with fetal growth parameters. The original observation presented in this report showed that duplication of ZNF331 could be a novel genetic cause of isolated IUGR and underlines the usefulness of CMA to investigate the genetic causes of isolated severe IUGR.
Asunto(s)
Cromosomas Humanos Par 19 , Retardo del Crecimiento Fetal/diagnóstico , Retardo del Crecimiento Fetal/genética , Duplicación de Gen , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Impresión Genómica , Adulto , Biopsia , Proteínas de Unión al ADN/genética , Epigénesis Genética , Femenino , Estudios de Asociación Genética/métodos , Pruebas Genéticas , Humanos , Inmunohistoquímica , Proteínas de Neoplasias/genética , Embarazo , Ultrasonografía PrenatalRESUMEN
BACKGROUND: Congenital anomalies of the kidney and urinary tract (CAKUT) represent a significant healthcare burden since it is the primary cause of chronic kidney in children. CNVs represent a recurrent molecular cause of CAKUT but the culprit gene remains often elusive. Our study aimed to define the gene responsible for CAKUT in patients with an 1q23.3q24.1 microdeletion. METHODS: We describe eight patients presenting with CAKUT carrying an 1q23.3q24.1 microdeletion as identified by chromosomal microarray analysis (CMA). Clinical features were collected, especially the renal and urinary tract phenotype, and extrarenal features. We characterised PBX1 expression and localisation in fetal and adult kidneys using quantitative RT-PCR and immunohistochemistry. RESULTS: We defined a 276-kb minimal common region (MCR) that only overlaps with the PBX1 gene. All eight patients presented with syndromic CAKUT. CAKUT were mostly bilateral renal hypoplasia (75%). The most frequent extrarenal symptoms were developmental delay and ear malformations. We demonstrate that PBX1 is strongly expressed in fetal kidneys and brain and expression levels decreased in adult samples. In control fetal kidneys, PBX1 was localised in nuclei of medullary, interstitial and mesenchymal cells, whereas it was present in endothelial cells in adult kidneys. CONCLUSIONS: Our results indicate that PBX1 haploinsufficiency leads to syndromic CAKUT as supported by the Pbx1-null mice model. Correct PBX1 dosage appears to be critical for normal nephrogenesis and seems important for brain development in humans. CMA should be recommended in cases of fetal renal anomalies to improve genetic counselling and pregnancy management.
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Haploinsuficiencia/genética , Factor de Transcripción 1 de la Leucemia de Células Pre-B/genética , Anomalías Urogenitales/genética , Reflujo Vesicoureteral/genética , Niño , Preescolar , Femenino , Feto/metabolismo , Genoma Humano , Humanos , Lactante , Riñón/anomalías , Riñón/embriología , Riñón/metabolismo , Riñón/patología , Masculino , SíndromeRESUMEN
Activating mutations of anaplastic lymphoma kinase (ALK) have been identified as important players in neuroblastoma development. Our goal was to evaluate the significance of overall ALK activation in neuroblastoma. Expression of phosphorylated ALK, ALK, and its putative ligands, pleiotrophin and midkine, was screened in 289 neuroblastomas and 56 paired normal tissues. ALK was expressed in 99% of tumors and phosphorylated in 48% of cases. Pleiotrophin and midkine were expressed in 58% and 79% of tumors, respectively. ALK activation was significantly higher in tumors than in paired normal tissues, together with ALK and midkine expression. ALK activation was largely independent of mutations and correlated with midkine expression in tumors. ALK activation in tumors was associated with favorable features, including a younger age at diagnosis, hyperdiploidy, and detection by mass screening. Antitumor activity of the ALK inhibitor TAE684 was evaluated in wild-type or mutated ALK neuroblastoma cell lines and xenografts. TAE684 was cytotoxic in vitro in all cell lines, especially those harboring an ALK mutation. TAE684 efficiently inhibited ALK phosphorylation in vivo in both F1174I and R1275Q xenografts but demonstrated antitumor activity only against the R1275Q xenograft. In conclusion, ALK activation occurs frequently during neuroblastoma oncogenesis, mainly through mutation-independent mechanisms. However, ALK activation is not associated with a poor outcome and is not always a driver of cell proliferation and/or survival in neuroblastoma.
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Proliferación Celular/genética , Transformación Celular Neoplásica/efectos de los fármacos , Neuroblastoma/metabolismo , Proteínas Tirosina Quinasas Receptoras/metabolismo , Adolescente , Quinasa de Linfoma Anaplásico , Línea Celular Tumoral , Transformación Celular Neoplásica/metabolismo , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Mutación/genética , Fosforilación/genética , Inhibidores de Proteínas Quinasas/farmacología , Piridinas/farmacología , Proteínas Tirosina Quinasas Receptoras/genética , Transducción de Señal/efectos de los fármacosRESUMEN
BACKGROUND: Neuroblastoma (NB) is a frequent pediatric tumor characterized by a poor prognosis where a majority of tumors progress despite intensive multimodality treatments. Autophagy, a self-degradative process in cells, could be induced by chemotherapy and be associated with chemoresistance. The aim of this study was to determine whether: 1) autophagy is present in NB, 2) chemotherapy modified its levels, and 3) its inhibition decreased chemoresistance. METHODS: Immunohistochemical stainings were performed on samples from 184 NB patients in order to verify the expression of LC3B, a specific marker for autophagy, and Beclin 1, a positive regulator of autophagy. In addition, we performed an in vitro study with six NB cell lines and six drugs (vincristine, doxorubicin, cisplatin temozolomide, LY294002 and syrolimus). Inhibition of autophagy was performed using ATG5 knockdown cells or hydroxychloroquine (HCQ). Cell survival was measured using the MTT cell proliferation assay. Autophagy was detected by monodansylcadaverine, confocal microscopy and Western blot. In vivo study with tumor xenografts in NSG mice was performed. RESULTS: Our results have indicated that autophagy was present at low levels in NB and was not a prognostic factor, while Beclin 1 was highly expressed in children with poor NB prognosis. However, autophagy levels increased after chemotherapy in vitro and in vivo. Tumor progression was significantly decreased in mice treated with a combination of HCQ and vincristine. CONCLUSIONS: Taken together, autophagy is present in NB, induced by chemotherapy and associated with chemoresistance, which is significantly reduced by its inhibition. Therefore, targeting autophagy represents a very attractive approach to develop new therapeutic strategies in NB.
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Antineoplásicos/farmacología , Autofagia/efectos de los fármacos , Autofagia/genética , Resistencia a Antineoplásicos/genética , Neuroblastoma/genética , Neuroblastoma/metabolismo , Animales , Antineoplásicos/uso terapéutico , Proteína 5 Relacionada con la Autofagia/genética , Proteína 5 Relacionada con la Autofagia/metabolismo , Biomarcadores , Línea Celular Tumoral , Proliferación Celular , Niño , Preescolar , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Estudios de Seguimiento , Técnicas de Inactivación de Genes , Humanos , Inmunohistoquímica , Lactante , Recién Nacido , Ratones , Ratones Noqueados , Estadificación de Neoplasias , Neuroblastoma/diagnóstico , Neuroblastoma/tratamiento farmacológico , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismoAsunto(s)
Antineoplásicos/uso terapéutico , Crizotinib/uso terapéutico , Neoplasias Pulmonares/tratamiento farmacológico , Mesotelioma/tratamiento farmacológico , Adolescente , Cisplatino/uso terapéutico , Femenino , Humanos , Pulmón/patología , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/patología , Mesotelioma/diagnóstico , Mesotelioma/patología , Pemetrexed/uso terapéutico , Medicina de PrecisiónRESUMEN
Alagille syndrome (ALGS) is a complex, multisystem disease associated with mutations in the JAG1 gene. In the liver, ALGS is characterized by paucity of intrahepatic bile ducts. Gene dosage analysis performed on a large, central regenerative nodule with preserved interlobular bile ducts of 2 unrelated ALGS patients, and on surrounding cirrhotic and ductopenic liver parenchyma, showed in both cases complete JAG1 heterozygous deletion in the regenerative nodule and the ductopenic liver, with no differences in gene dosage. Thus, JAG1 mosaicism and differential haploinsufficiency do not explain the presence of bile ducts in centrally located regenerative nodules.
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Síndrome de Alagille/patología , Conductos Biliares Intrahepáticos/patología , Proteínas de Unión al Calcio/genética , Heterocigoto , Péptidos y Proteínas de Señalización Intercelular/genética , Hígado/patología , Proteínas de la Membrana/genética , Mosaicismo , Mutación , Síndrome de Alagille/genética , Humanos , Proteína Jagged-1 , Neoplasias Hepáticas/genética , Masculino , Fenotipo , Proteínas Serrate-JaggedRESUMEN
The insulin receptor (IR) plays an important role in insulin signal transduction, the defect of which is believed to be the root cause of type 2 diabetes. In 3T3-L1 adipocytes as in other cell types, the mature IR is a heterotetrameric cell surface glycoprotein composed of two α subunits and two ß subunits. Our objective in our study, is to understand how the desialylation of N-glycan chains, induced by elastin-derived peptides, plays a major role in the function of the IR. Using the 3T3-L1 adipocyte line, we show that removal of the sialic acid from N-glycan chains (N893 and N908), induced by the elastin receptor complex (ERC) and elastin derived-peptides (EDPs), leads to a decrease in the autophosphorylation activity of the insulin receptor. We demonstrate by molecular dynamics approaches that the absence of sialic acids on one of these two sites is sufficient to generate local and general modifications of the structure of the IR. Biochemical approaches highlight a decrease in the interaction between insulin and its receptor when ERC sialidase activity is induced by EDPs. Therefore, desialylation by EDPs is synonymous with a decrease of IR sensitivity in adipocytes and could thus be a potential source of insulin resistance associated with diabetic conditions.
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Células 3T3-L1 , Adipocitos , Elastina , Insulina , Receptor de Insulina , Receptores de Superficie Celular , Ácidos Siálicos , Animales , Receptor de Insulina/metabolismo , Ratones , Adipocitos/metabolismo , Insulina/metabolismo , Elastina/metabolismo , Ácidos Siálicos/metabolismo , Fosforilación , Resistencia a la Insulina , Simulación de Dinámica Molecular , Péptidos/metabolismo , Péptidos/farmacología , Péptidos/química , Ácido N-Acetilneuramínico/metabolismo , Transducción de SeñalRESUMEN
BACKGROUND: Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is the only curative treatment for myeloid malignancies such as some acute myeloid leukemias (AML) and high-risk myelodysplastic syndromes (MDS). It aims to eradicate the malignant clone using immunocompetent donor cells (graft-versus-leukemia effect, GVL). Unfortunately, relapse is the primary cause of transplant failure mainly related on HLA loss or downregulation and upregulation of inhibitory ligands on blasts which result in donor immune effector dysfunctions. METHODS: Between 2018 and 2021, we conducted a monocentric prospective study including 61 consecutive patients transplanted for AML or high-risk MDS. We longitudinally investigated immune cells at days + 30, + 90 and + 180 post-transplant from bone marrow and peripheral blood. We assessed the dynamics between myeloid derived suppressor cells (MDSCs) and T-cells. RESULTS: Among the 61 patients, 45 did not relapse over the first 12 months while 16 relapsed during the first year post-transplant. Through months 1 to 6, comparison with healthy donors revealed an heterogenous increase in MDSC frequency. In all recipients, the predominant MDSC subset was granulocytic with no specific phenotypic relapse signature. However, in relapsed patients, in vitro and in vivo functional analyses revealed that MDSCs from peripheral blood were highly immunosuppressive from day + 30 onwards, with an activated NLRP3 inflammasome signature. Only circulating immunosuppressive MDSCs were statistically correlated to circulating double-positive Tim3+LAG3+ exhausted T cells. CONCLUSION: Our simple in vitro functional assay defining MDSC immunosuppressive properties might serve as an early biomarker of relapse and raise the question of new preventive treatments targeting MDSCs in the future. Trial registration NCT03357172.
Asunto(s)
Adenocarcinoma Mucinoso/congénito , Adenocarcinoma Mucinoso/genética , Malformación Adenomatoide Quística Congénita del Pulmón/genética , Neoplasias Pulmonares/congénito , Neoplasias Pulmonares/genética , Proteínas Proto-Oncogénicas p21(ras)/genética , Adenocarcinoma Mucinoso/patología , Malformación Adenomatoide Quística Congénita del Pulmón/patología , Femenino , Humanos , Recién Nacido , Neoplasias Pulmonares/patología , Embarazo , Diagnóstico PrenatalRESUMEN
Neuroblastoma (NB) is the most common and lethal extracranial solid tumor of childhood. Despite aggressive therapy, more than half of the children with advanced NB will die of uncontrolled metastatic disease. After chemotherapy, tumor-initiating cells (TICs) could persist, cause relapses and metastasis. The aim of this study is to demonstrate the tumor-initiating properties of CD133high NB cells and to identify new specific genetic abnormalities. Isolation of the CD133high cell population from NB cell lines was followed by neurosphere formation, soft agar assays, and orthotopic injections in NOD/SCID/IL2Rγc-null mice. A differential genotyping analysis was performed with Affymetrix SNP 6.0 arrays on CD133low and CD133high populations and the frequency of the abnormalities of 36 NB tumors was determined. Our results show that CD133high NB cells possess tumor-initiating properties, as CD133high cells formed significantly more neurospheres and produced significantly more colonies in soft agar than CD133low. Injection of 500 CD133high cells was sufficient to generate primary tumors and frequent metastases in mice. Differential genotyping analysis demonstrated two common regions with gains (16p13.3 and 19p13.3) including the gene EFNA2 in the CD133high population, and two with loss of heterozygosity (16q12.1 and 21q21.3) in the CD133low population. The gain of EFNA2 correlated with increased expression of the corresponding protein. These abnormalities were found in NB samples and some were significantly correlated with CD133 expression. Our results show that CD133high NB cells have TICs properties and present different genotyping characteristics compared to CD133low cells. Our findings reveal insights into new therapeutic targets in NB TICs.