RESUMEN
PATZ1-rearranged sarcomas are well-recognized tumors as part of the family of round cell sarcoma with EWSR1-non-ETS fusions. Whether PATZ1-rearranged central nervous system (CNS) tumors are a distinct tumor type is debatable. We thoroughly characterized a pediatric series of PATZ1-rearranged CNS tumors by chromosome microarray analysis (CMA), DNA methylation analysis, gene expression profiling and, when frozen tissue is available, optical genome mapping (OGM). The series consisted of 7 cases (M:F=1.3:1, 1-17 years, median 12). On MRI, the tumors were supratentorial in close relation to the lateral ventricles (intraventricular or iuxtaventricular), preferentially located in the occipital lobe. Two major histologic groups were identified: one (4 cases) with an overall glial appearance, indicated as "neuroepithelial" (NET) by analogy with the corresponding methylation class (MC); the other (3 cases) with a predominant spindle cell sarcoma morphology, indicated as "sarcomatous" (SM). A single distinct methylation cluster encompassing both groups was identified by multidimensional scaling analysis. Despite the epigenetic homogeneity, unsupervised clustering analysis of gene expression profiles revealed 2 distinct transcriptional subgroups correlating with the histologic phenotypes. Interestingly, genes implicated in epithelial-mesenchymal transition and extracellular matrix composition were enriched in the subgroup associated to the SM phenotype. The combined use of CMA and OGM enabled the identification of chromosome 22 chromothripsis in all cases suitable for the analyses, explaining the physical association of PATZ1 to EWSR1 or MN1. Six patients are currently disease-free (median follow-up 30 months, range 12-92). One patient of the SM group developed spinal metastases at 26 months from diagnosis and is currently receiving multimodal therapy (42 months). Our data suggest that PATZ1-CNS tumors are defined by chromosome 22 chromothripsis as causative of PATZ1 fusion, show peculiar MRI features (eg, relation to lateral ventricles, supratentorial frequently posterior site), and, although epigenetically homogenous, encompass 2 distinct histologic and transcriptional subgroups.
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Cromotripsis , Sarcoma , Neoplasias de los Tejidos Blandos , Humanos , Niño , Factores de Transcripción/genética , Sarcoma/genética , Proteína EWS de Unión a ARN/genética , Sistema Nervioso Central/patología , Transcriptoma , Neoplasias de los Tejidos Blandos/genética , Proteínas Represoras/genética , Factores de Transcripción de Tipo Kruppel/genéticaRESUMEN
BACKGROUND: IgA nephropathy (IgAN) is the most common glomerulonephritis worldwide. While studies have primarily focused on identifying risk factors for disease progression, very few data exist on the likelihood of achieving complete recovery from the disease. METHODS: We conducted a single-center retrospective study on all consecutive patients with biopsy-proven IgAN diagnosed between 1986 and 2018 in our pediatric center. Biopsies were classified according to the MEST-C Oxford classification score. "Complete clinical remission" was defined as the absence of proteinuria, hematuria, and hypertension in patients with normal kidney function who had been off therapy for more than 2 years. RESULTS: Overall, 153 patients with age at onset of 10.6 ± 4 years were enrolled in the study. Of these, 41 achieved "complete clinical remission." The estimated probability of complete clinical remission at 10 years was 43% (95%CI 33-54). However, seven patients relapsed within 10 years. Multivariable analysis showed that higher age at onset (HR 0.89, 95%CI 0.80-0.98, p = 0.017) and segmental glomerulosclerosis lesions (HR 0.28, 95%CI 0.10-0.79, p = 0.017) decreased significantly the chances of achieving complete clinical remission. Immunosuppressive therapy was not significantly associated with clinical outcomes. CONCLUSIONS: Approximately one-third of patients with pediatric-onset IgAN achieve prolonged remission, in particular, very young children at disease onset without sclerotic glomerular lesions. Longer term follow-up is needed to assess if these patients have achieved permanent remission.
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Glomerulonefritis por IGA , Glomeruloesclerosis Focal y Segmentaria , Humanos , Niño , Preescolar , Adolescente , Glomerulonefritis por IGA/tratamiento farmacológico , Estudios Retrospectivos , Tasa de Filtración Glomerular , Glomérulos Renales/patología , Glomeruloesclerosis Focal y Segmentaria/patología , Proteinuria/patología , Riñón/patologíaRESUMEN
In the pediatric population, BCL6-correpresor gene (BCOR)-upregulated tumors include primitive myxoid mesenchymal tumors/undifferentiated sarcomas (PMMTI/UND), clear cell sarcomas of the kidney (CCSK), and high-grade neuroepithelial tumors (HG-NET). We investigated DNA methylation (DNAm) and copy number variation (CNV) profiling in these tumors (N = 34) using an Illumina EPIC BeadChip to better define the potential use of these tools to confirm diagnosis and predict outcomes. Twenty-seven tumors from 25 patients (age range, 0-10 years), showed molecular confirmation of genetic abnormalities as follows: BCOR internal tandem duplication in 14 PMMTI/UND, 8 CCSK, and 3 HG-NET and YWHAE fusions in 2 PMMTI/UND. The remaining 7 cases lacking informative molecular data were analyzed by immunophenotyping and were included in the study as a training cohort, clearly separated from the main study group. These were 4 PMMTI, 1 HG-NET, and 1 CCSK in which poor RNA preservation precluded the confirmation of BCOR rearrangements and 1 CCSK in which no rearrangements were found. DNAm data were compared with those of brain tumor and/or sarcoma classifier. Differentially methylated regions (DMRs) were analyzed in the 3 groups. Twenty-two cases of the 24 molecularly confirmed PMMTI/UND and CCSK and 3 of 6 of those with only immunophenotyping were classified within the methylation class "BCOR-altered sarcoma family" with optimal calibrated scores. PMMTI/UND and CCSK showed similar methylation profiles, whereas thousands of DMRs and significantly enriched pathways were evident between soft tissue/kidney tumors and HG-NET. The CNV analysis showed an overall flat profile in 19 of the 31 evaluable tumors (8/10 CCSK; 9/18 PMMTI/UND; 2/4 HG-NET). The most frequent CNVs were 1q gain and 9p and 10q loss. Follow-up time data were available for 20 patients: ≥2 CNV significantly correlated with a worse overall survival rate. In conclusion, soft tissue and kidney BCOR sarcomas matched with BCOR-altered sarcoma methylation class, whereas those from the brain matched with the central nervous system tumor classifier HG-NET BCOR, supporting the notion that DNAm profiling is an informative diagnostic tool. CNV alterations were associated with a more aggressive clinical behavior.
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Neoplasias Renales , Sarcoma , Neoplasias de los Tejidos Blandos , Niño , Humanos , Recién Nacido , Lactante , Preescolar , Metilación de ADN , Variaciones en el Número de Copia de ADN , Riñón , Neoplasias Renales/genética , Sarcoma/genética , Neoplasias de los Tejidos Blandos/genética , Proteínas Proto-Oncogénicas/genética , Proteínas Represoras/genéticaRESUMEN
BACKGROUND: C3 glomerulonephritis (C3GN) is a subtype of C3 glomerulopathy (C3G), characterized by dysregulation of the alternative pathway of complement and by dominant C3 by immunofluorescence on the kidney biopsy. There is no approved treatment for patients with C3G. Immunosuppressive drugs as well as biologics have been used with limited success. In recent decades, substantial advances in the understanding of the complement system have led to the development of new complement inhibitors. Avacopan (CCX168) is an orally administered small-molecule C5aR antagonist that blocks the effects of C5a, one of the most potent pro-inflammatory mediators of the complement system. CASE REPORT: We describe a child with biopsy-proven C3GN treated with avacopan. She was enrolled in the ACCOLADE double-blind placebo-controlled Phase 2 study (NCT03301467), where during the first 26 weeks she was randomized to receive an avacopan-matching placebo orally twice daily, while in the following 26 weeks, the study was open-label and she received avacopan. After a wash-out period, she was restarted on avacopan through an expanded access program. CONCLUSIONS: In this case, use of avacopan in a pediatric patient with C3GN was safe and well tolerated. On avacopan, the patient was able to discontinue mycophenolate mofetil (MMF) while maintaining remission.
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Glomerulonefritis Membranoproliferativa , Glomerulonefritis , Niño , Femenino , Humanos , Complemento C3 , Glomerulonefritis/tratamiento farmacológico , Glomerulonefritis Membranoproliferativa/patología , Resultado del Tratamiento , Ensayos Clínicos Controlados Aleatorios como AsuntoAsunto(s)
Enfermedades Autoinmunes , Inmunoterapia Adoptiva , Receptores Quiméricos de Antígenos , Linfocitos T , Animales , Humanos , Enfermedades Autoinmunes/terapia , Enfermedades Autoinmunes/inmunología , Receptores de Antígenos de Linfocitos T/uso terapéutico , Receptores Quiméricos de Antígenos/inmunología , Linfocitos T/inmunología , Antígenos CD19 , Lupus Eritematoso Sistémico/inmunología , Lupus Eritematoso Sistémico/terapiaRESUMEN
Astroblastomas are neuroepithelial tumours defined by the presence of MN1 rearrangement and are typically located in the cerebral hemispheres. Rare cases of astroblastoma-like tumours carrying an EWSR1-BEND2 fusion have been recently described in the brain stem and spinal cord. We report a paediatric case of neuroepithelial astroblastoma-like tumour occurring in the spine and carrying a novel MAMLD1-BEND2 fusion. We believe that our case aligns with the rare astroblastoma-like tumours with EWSR1-BEND2 fusion, in terms of non-hemispheric location, pathology, methylation profile and activation of BEND2 transcription. Whether they may represent a distinct entity or a variant of MN1-altered astroblastoma is not clear.
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Neoplasias Encefálicas , Neoplasias Neuroepiteliales , Neoplasias de la Médula Espinal , Neoplasias Encefálicas/patología , Niño , Aberraciones Cromosómicas , Proteínas de Unión al ADN , Humanos , Neoplasias Neuroepiteliales/genética , Neoplasias Neuroepiteliales/patología , Proteínas Nucleares , Neoplasias de la Médula Espinal/genética , Transactivadores , Factores de Transcripción , Proteínas Supresoras de Tumor/genéticaRESUMEN
BACKGROUND: Brain death secondary to traumatic brain injury is one of the main sources of organs for transplantation but it can be associated with disseminated intravascular coagulation, which has been considered a relative contraindication for kidney donation. METHODS: We describe two successful pediatric cases of kidney transplantation from a single donor with disseminated intravascular coagulation. RESULTS: A 17-year-old male donor died from head injury and both kidneys were offered to our center. Within 24 h, donor's Hb and platelets dropped to 8.3 g/dl and 32 000/mcl, respectively, serum creatinine reached 2.01 mg/dl, and urinalysis showed proteinuria (300 mg/dl). Pre-implant biopsy showed massive occlusion of glomerular capillaries by fibrin thrombi containing fragmented red blood cells and inflammatory cells, and acute tubular damage. Arterioles and small arteries were spared. A diagnosis of DIC was made. The kidneys were transplanted in a 16-year-old girl and a 13-year-old boy. Slow recovery of graft function was observed in both recipients. On post-operative day 3, platelets dropped to a minimum value of 66 000 and 86 000/mcl, respectively. Diuresis was always present. On day 4, platelets started to rise. Six months later, both recipients attained normal renal function. A six-month protocol biopsy showed no microthrombi or other signs of disseminated intravascular coagulation. CONCLUSIONS: Despite the limited data available in literature, the outcome of these two cases is positive. Thus, pre-implant kidney biopsy, even if it reveals massive thrombotic occlusion of glomerular capillaries compatible with diagnosis of disseminated intravascular coagulation, should not be considered an absolute contraindication to transplantation.
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Lesiones Traumáticas del Encéfalo/fisiopatología , Coagulación Intravascular Diseminada/patología , Selección de Donante/métodos , Glomérulos Renales/patología , Trasplante de Riñón , Adolescente , Coagulación Intravascular Diseminada/etiología , Femenino , Supervivencia de Injerto , Humanos , Glomérulos Renales/trasplante , MasculinoRESUMEN
C3 glomerulopathy is a relatively new clinical entity that represents a challenge both to diagnose and to treat. As new therapeutic agents that act as complement inhibitors become available, many with an oral formulation, a better understanding of this disease and of the underlying complement dysregulation driving it has become increasingly useful to optimize patient care. Moreover, recent advances in research have clarified the role of complement in other glomerular diseases in which its role was less established, namely in immune-complex membranoproliferative glomerulonephritis (IC-MPGN), ANCA-vasculitis, IgA nephropathy, and idiopathic membranous nephropathy. Complement inhibitors are being studied in adult and adolescent clinical trials for these indications. This review summarizes current knowledge and future perspectives on every aspect of the diagnosis and management of C3 glomerulopathy and elucidates current understanding of the role of complement in this condition and in other glomerular diseases in children. An overview of ongoing trials involving therapeutic agents targeting complement in glomerular diseases is also provided.
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Glomerulonefritis Membranoproliferativa , Glomerulonefritis , Enfermedades Renales , Adolescente , Adulto , Niño , Inactivadores del Complemento/uso terapéutico , Femenino , Glomerulonefritis/diagnóstico , Glomerulonefritis/tratamiento farmacológico , Glomerulonefritis Membranoproliferativa/tratamiento farmacológico , Humanos , Enfermedades Renales/diagnóstico , Enfermedades Renales/tratamiento farmacológico , MasculinoRESUMEN
As a relevant element of novelty, the fifth CNS WHO Classification highlights the distinctive pathobiology underlying gliomas arising primarily in children by recognizing for the first time the families of paediatric-type diffuse gliomas, both high-grade and low-grade. This review will focus on the family of paediatric-type diffuse high-grade gliomas, which includes four tumour types: 1) Diffuse midline glioma H3 K27-altered; 2) Diffuse hemispheric glioma H3 G34-mutant; 3) Diffuse paediatric-type high-grade glioma H3-wildtype and IDH-wildtype; and 4) Infant-type hemispheric glioma. The essential and desirable diagnostic criteria as well as the entities entering in the differential will be discussed for each tumour type. A special focus will be given on the issues encountered in the daily practice, especially regarding the diagnosis of the diffuse paediatric-type high-grade glioma H3-wildtype and IDH-wildtype. The advantages and the limits of the multiple molecular tests which may be utilised to define the entities of this tumour family will be evaluated in each diagnostic context.
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Neoplasias Encefálicas , Glioma , Humanos , Niño , Mutación , Glioma/diagnóstico , Organización Mundial de la SaludRESUMEN
Pediatric low-grade gliomas (pLGGs) are the most frequent brain tumor in children. Adjuvant treatment, consisting in chemotherapy and radiotherapy, is often necessary if a complete surgical resection cannot be obtained. Traditional treatment approaches result in a significant long-term morbidity, with a detrimental impact on quality of life. Dysregulation of the mitogen-activated protein kinase (MAPK) pathway is the molecular hallmark of pLGGs and hyperactivation of the downstream mammalian target of rapamycin (mTOR) pathway is frequently observed. We report clinical and radiological results of front-line treatment with everolimus in 10 consecutive patients diagnosed with m-TOR positive pLGGs at the Bambino Gesù Children's Hospital in Rome, Italy. Median duration of treatment was 19 months (range from 13-60). Brain magnetic resonance imaging showed stable disease in 7 patients, partial response in 1 and disease progression in 2. Therapy-related adverse events were always reversible after dose reduction or temporary treatment interruption. To the best of our knowledge, this is the first report of everolimus treatment for chemo- and radiotherapy-naïve children with pLGG. Our results provide preliminary support, despite low sample size, for the use of everolimus as target therapy in pLGG showing lack of progression with a manageable toxicity profile.
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AIMS: Histiocytoses are a heterogeneous group of localized or disseminated diseases. Clinical presentation and patients' outcome vary greatly, ranging from mild to life-threatening disorders. Rare cases of systemic or localized histiocytosis harboring ALK rearrangement have been reported. METHODS: Two cases of CNS histiocytosis were thoroughly investigated by implementing multiple molecular tests, i.e. FISH, RT-qPCR, NGS analysis. RESULTS: In a 10-month old girl (patient #1), MRI showed two left hemispheric lesions and a right fronto-mesial lesion histologically consisting of a moderately cellular infiltrative proliferation, composed by CD68(PGM1)+/CD163+ spindle cells. ALK 5'/3'-imbalance and a KIF5B(exon 24)-ALK(exon 20) fusion were documented by RT-qPCR and NGS analysis, respectively. A subsequent CT scan showed multiple hepatic and pulmonary lesions. The patient was started on chemotherapy (vinblastine) associated to an ALK-inhibitor (Alectinib) with remarkable response. In a 11-year-old girl (patient #2), MRI showed a right frontal 1.5 cm lesion. Neuropathological examination revealed a histiocytic proliferation composed by medium sized CD68(PGM1)+/HLA-DR+ cells, showing moderate ALK1 positivity. ALK rearrangement and a KIF5B(exon 24)-ALK(exon 20) fusion were demonstrated also in this case. Subsequent CT, 18F-FDG-PET and MRI scans showed the presence of a single right femoral lesion, proved to be a fibrous cortical defect. CONCLUSIONS: In ALK-histiocytoses, CNS involvement may occur as part of a systemic disease or, rarely, as its only primary disease localization, which could remain otherwise asymptomatic. The diagnosis often relies on neuropathological examination of brain biopsy, which may pose a diagnostic challenge due to the variable histopathological features. An integrated histological and molecular approach in such cases is recommended.
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Quinasa de Linfoma Anaplásico/metabolismo , Sistema Nervioso Central/patología , Histiocitosis/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/uso terapéutico , Biopsia/métodos , Sistema Nervioso Central/efectos de los fármacos , Niño , Femenino , Histiocitosis/diagnóstico , Histiocitosis/patología , Humanos , Lactante , Proteínas Tirosina Quinasas Receptoras/efectos de los fármacos , Proteínas Tirosina Quinasas Receptoras/metabolismoRESUMEN
Medulloblastoma (MB) is a childhood malignant brain tumour comprising four main subgroups characterized by different genetic alterations and rate of mortality. Among MB subgroups, patients with enhanced levels of the c-MYC oncogene (MBGroup3) have the poorest prognosis. Here we identify a previously unrecognized role of the pro-autophagy factor AMBRA1 in regulating MB. We demonstrate that AMBRA1 expression depends on c-MYC levels and correlates with Group 3 patient poor prognosis; also, knockdown of AMBRA1 reduces MB stem potential, growth and migration of MBGroup3 stem cells. At a molecular level, AMBRA1 mediates these effects by suppressing SOCS3, an inhibitor of STAT3 activation. Importantly, pharmacological inhibition of autophagy profoundly affects both stem and invasion potential of MBGroup3 stem cells, and a combined anti-autophagy and anti-STAT3 approach impacts the MBGroup3 outcome. Taken together, our data support the c-MYC/AMBRA1/STAT3 axis as a strong oncogenic signalling pathway with significance for both patient stratification strategies and targeted treatments of MBGroup3.
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Proteínas Adaptadoras Transductoras de Señales/genética , Autofagia/efectos de los fármacos , Neoplasias Cerebelosas/tratamiento farmacológico , Meduloblastoma/tratamiento farmacológico , Factor de Transcripción STAT3/genética , Transducción de Señal/efectos de los fármacos , Animales , Línea Celular Tumoral , Movimiento Celular/genética , Niño , Técnicas de Silenciamiento del Gen , Humanos , Ratones , Ratones Endogámicos C57BL , Células Madre Neoplásicas , Pronóstico , Proteínas Proto-Oncogénicas c-myc/biosíntesis , Proteínas Proto-Oncogénicas c-myc/genética , Proteína 3 Supresora de la Señalización de Citocinas/antagonistas & inhibidoresRESUMEN
Proteinuria is one of the most typical manifestations of kidney involvement in Systemic Lupus Erythematosus (SLE). We report the case of a 23-year-old woman with a 6-year-long history of SLE presenting with proteinuria after a three-year remission on hydroxychloroquine. Kidney histological examination showed alterations inconsistent with lupus nephritis and suggestive of hydroxychloroquine toxicity or Fabry disease. The latter was confirmed by genetic assay.
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Enfermedad de Fabry/genética , Hidroxicloroquina/toxicidad , Lupus Eritematoso Sistémico/diagnóstico , Nefritis Lúpica/inducido químicamente , Proteinuria/etiología , Antirreumáticos/administración & dosificación , Antirreumáticos/uso terapéutico , Antirreumáticos/toxicidad , Biopsia , Diagnóstico Diferencial , Terapia de Reemplazo Enzimático/métodos , Enfermedad de Fabry/diagnóstico , Enfermedad de Fabry/terapia , Enfermedad de Fabry/orina , Femenino , Humanos , Hidroxicloroquina/administración & dosificación , Hidroxicloroquina/uso terapéutico , Riñón/efectos de los fármacos , Riñón/patología , Lupus Eritematoso Sistémico/tratamiento farmacológico , Lupus Eritematoso Sistémico/orina , Nefritis Lúpica/patología , Nefritis Lúpica/orina , Inducción de Remisión , Resultado del Tratamiento , Adulto JovenRESUMEN
Membranous nephropathy results from subepithelial antigen-antibody complex deposition along the glomerular basement membrane. Although PLA2R, THSD7A, and NELL-1 account for a majority (about 80%) of the target antigens, the target antigen in the remaining cases is not known. Using laser microdissection of PLA2R-negative glomeruli of patients with membranous nephropathy followed by mass spectrometry we identified a unique protein, Semaphorin 3B, in three cases. Mass spectrometry failed to detect Semaphorin-3B in 23 PLA2R-associated cases of membranous nephropathy and 88 controls. Semaphorin 3B in all three cases was localized to granular deposits along the glomerular basement membrane by immunohistochemistry. Next, an additional eight cases of Semaphorin 3B-associated membranous nephropathy were identified in three validation cohorts by immunofluorescence microscopy. In four of 11 cases, kidney biopsy also showed tubular basement membrane deposits of IgG on frozen sections. Confocal microscopy showed that both IgG and Semaphorin 3B co-localized to the glomerular basement membrane. Western blot analysis of five available sera showed reactivity to reduced Semaphorin 3B in four of four patients with active disease and no reactivity in one patient in clinical remission; there was also no reactivity in control sera. Eight of the 11 cases of Semaphorin 3B-associated membranous nephropathy were pediatric cases. Furthermore, in five cases, the disease started at or below the age of two. Thus, Semaphorin 3B-associated membranous nephropathy appears to be a distinct type of disease; more likely to be present in pediatric patients.
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Glomerulonefritis Membranosa , Semaforinas , Niño , Membrana Basal Glomerular , Glomerulonefritis Membranosa/diagnóstico , Humanos , Inmunohistoquímica , Glicoproteínas de Membrana , Microscopía ConfocalRESUMEN
Cystinosis is an autosomal recessive lysosomal storage disorder characterized by the defective transport of the amino acid cystine out of the lysosome due to a deficiency of cystinosin, the lysosomal cystine transporter. Patients have lysosomal cystine accumulation in various tissues, leading to cellular stress and damage, particularly in the kidney, cornea, and other extrarenal tissues. Cysteamine, a cystine-depleting agent, improves survival and delays the progression of disease, but it does not prevent the development of either renal failure or extrarenal complications. Furthermore, the drug has severe adverse effects that significantly reduce patient compliance. Allogeneic hematopoietic stem cell transplantation (HSCT) is currently established as a therapeutic option for many inborn errors of metabolism, where the main pathologic driving factor is an enzyme deficiency. Recent studies in the cystinosis mouse-model suggested that HSCT could be a curative treatment alternative to cysteamine therapy. We treated a 16-year-old boy who had infantile cystinosis and side effects of cysteamine therapy with HSCT. We were able to demonstrate successful transfer of the wild-type cystinosin protein and CTNS mRNA to nonhematological epithelial cells in the recipient, as well as a decrease in the tissue cystine-crystal burden. This is the first report of allogeneic HSCT in a patient with cystinosis, the prototype of lysosomal membrane-transporter disorders.
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Sistemas de Transporte de Aminoácidos Neutros/administración & dosificación , Cistinosis/terapia , Células Epiteliales/metabolismo , Trasplante de Células Madre Hematopoyéticas , Adolescente , Sistemas de Transporte de Aminoácidos Neutros/genética , Sistemas de Transporte de Aminoácidos Neutros/metabolismo , Cistinosis/genética , Humanos , Masculino , Mutación , Pronóstico , Trasplante HomólogoRESUMEN
Extraventricular neurocytoma (EVN) is a rare primary brain tumor occurring in brain parenchyma outside the ventricular system. Histopathological characteristics resemble those of central neurocytoma but exhibit a wider morphologic spectrum. Accurate diagnosis of these histologically heterogeneous tumors is often challenging because of the overlapping morphological features and the lack of defining molecular markers. Here, we explored the molecular landscape of 40 tumors diagnosed histologically as EVN by investigating copy number profiles and DNA methylation array data. DNA methylation profiles were compared with those of relevant differential diagnoses of EVN and with a broader spectrum of diverse brain tumor entities. Based on this, our tumor cohort segregated into different groups. While a large fraction (n = 22) formed a separate epigenetic group clearly distinct from established DNA methylation profiles of other entities, a subset (n = 14) of histologically diagnosed EVN grouped with clusters of other defined entities. Three cases formed a small group close to but separated from the epigenetically distinct EVN cases, and one sample clustered with non-neoplastic brain tissue. Four additional samples originally diagnosed otherwise were found to molecularly resemble EVN. Thus, our results highlight a distinct DNA methylation pattern for the majority of tumors diagnosed as EVN, but also indicate that approximately one third of morphological diagnoses of EVN epigenetically correspond to other brain tumor entities. Copy number analysis and confirmation through RNA sequencing revealed FGFR1-TACC1 fusion as a distinctive, recurrent feature within the EVN methylation group (60%), in addition to a small number of other FGFR rearrangements (13%). In conclusion, our data demonstrate a specific epigenetic signature of EVN suitable for characterization of these tumors as a molecularly distinct entity, and reveal a high frequency of potentially druggable FGFR pathway activation in this tumor group.
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Neoplasias Encefálicas/genética , Proteínas Fetales/genética , Proteínas Asociadas a Microtúbulos/genética , Neurocitoma/genética , Proteínas Nucleares/genética , Receptor Tipo 1 de Factor de Crecimiento de Fibroblastos/genética , Metilación de ADN/genética , Femenino , Proteínas Fetales/metabolismo , Histonas/genética , Humanos , Isocitrato Deshidrogenasa/genética , Isocitrato Deshidrogenasa/metabolismo , Estimación de Kaplan-Meier , Antígeno Ki-67/metabolismo , Masculino , Proteínas Asociadas a Microtúbulos/metabolismo , Proteínas Nucleares/metabolismo , Proteínas de Fusión Oncogénica/genética , Proteínas de Fusión Oncogénica/metabolismo , Receptor Tipo 1 de Factor de Crecimiento de Fibroblastos/metabolismo , Estudios Retrospectivos , TranscriptomaRESUMEN
BACKGROUND: Kidney transplantation is the best treatment for children with end-stage kidney disease. Early results have improved, but late graft loss is still a major problem. Non-invasive, fully reliable early biomarkers of acute rejection are currently missing. METHODS: Our aim was to evaluate the efficacy of protocol biopsies (PBXs) in a pediatric population. During 11 years, 209 renal transplantations were performed in 204 pediatric patients. Biopsies were performed 3-6 months, 1 year, and 5 years after transplantation. Procedure-related complications were systematically looked for by means of ultrasound scans. RESULTS: Unexpected findings (mainly subclinical rejections) requiring therapeutic intervention were found in 19.3% biopsies performed at 3-6 months, in 18.4% in 12-month biopsies and in none of those performed after 5 years. The 13.6% patients at 12-month biopsies and 23.6% at 5-year biopsies showed calcineurin inhibitor (CNI) toxicity. Interstitial fibrosis and tubular atrophy (IF/TA) was found in 17.6 and 83.6% of patients at 12-month and 5-year biopsies, respectively. Complications of the PBX were infrequent. Five-year estimated glomerular filtration rate (GFR) was not significantly different in patients who received treatment for any cause and patients with normal histology. CONCLUSIONS: Although we do not have a control group, we may speculate that patients who received treatment returned to a "standard" condition possibly improving final outcome. Protocol biopsies are a powerful diagnostic tool for the management of pediatric renal transplant recipients. In view of the lack of evidence that biopsies taken 5 years after transplantation lead to any therapeutic change, their use should be reconsidered.
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Aloinjertos/patología , Protocolos Clínicos/normas , Rechazo de Injerto/diagnóstico , Fallo Renal Crónico/cirugía , Trasplante de Riñón/efectos adversos , Riñón/patología , Adolescente , Aloinjertos/diagnóstico por imagen , Aloinjertos/inmunología , Biopsia/efectos adversos , Biopsia/normas , Biopsia/estadística & datos numéricos , Inhibidores de la Calcineurina/administración & dosificación , Inhibidores de la Calcineurina/efectos adversos , Niño , Femenino , Tasa de Filtración Glomerular , Rechazo de Injerto/inmunología , Rechazo de Injerto/patología , Rechazo de Injerto/prevención & control , Supervivencia de Injerto/efectos de los fármacos , Humanos , Inmunosupresores/administración & dosificación , Inmunosupresores/efectos adversos , Riñón/diagnóstico por imagen , Riñón/inmunología , Masculino , Complicaciones Posoperatorias/diagnóstico por imagen , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Guías de Práctica Clínica como Asunto , Estudios Retrospectivos , Factores de Tiempo , Resultado del Tratamiento , Ultrasonografía DopplerRESUMEN
Transient infantile hypertriglyceridemia (HTGT1; OMIM #614480) is a rare autosomal recessive disorder, which manifests in early infancy with transient hypertriglyceridemia, hepatomegaly, elevated liver enzymes, persistent fatty liver and hepatic fibrosis. This rare clinical entity is caused by inactivating mutations in the GPD1 gene, which encodes the cytosolic isoform of glycerol-3-phosphate dehydrogenase. Here we report on four patients from three unrelated families of diverse ethnic origins, who presented with hepatomegaly, liver steatosis, hypertriglyceridemia, with or without fasting ketotic hypoglycemia. Whole exome sequencing revealed the affected individuals to harbor deleterious biallelic mutations in the GPD1 gene, including the previously undescribed c.806G > A (p.Arg269Gln) and c.640T > C (p.Cys214Arg) mutations. The clinical features in three of our patients showed several differences compared to the original reports. One subject presented with recurrent episodes of fasting hypoglycemia along with hepatomegaly, hypetriglyceridemia, and elevated liver enzymes; the second showed a severe liver disease, with intrahepatic cholestasis associated with kidney involvement; finally, the third presented persistent hypertriglyceridemia at the age of 30 years. These findings expand the current knowledge of this rare disorder, both with regard to the phenotype and molecular basis. The enlarged phenotypic spectrum of glycerol-3-phosphate dehydrogenase 1 deficiency can mimic other inborn errors of metabolism with liver involvement and should alert clinicians to recognize this entity by considering GPD1 mutations in appropriate clinical settings.
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Glicerolfosfato Deshidrogenasa/deficiencia , Glicerolfosfato Deshidrogenasa/genética , Mutación/genética , Adolescente , Adulto , Niño , Preescolar , Hepatomegalia/genética , Humanos , Hipertrigliceridemia/genética , Hígado/patología , Cirrosis Hepática/genética , FenotipoRESUMEN
Medulloblastoma is the most common pediatric brain tumor. We describe a child with tuberous sclerosis complex that developed a Group 3, myc overexpressed, metastatic medulloblastoma (MB). Considering the high risk of treatment-induced malignancies, a tailored therapy, omitting radiation, was given. Based on the evidence of mammalian target of rapamycin mTORC, mTOR Complex; RAS, Rat sarcoma; RAF, rapidly accelerated fibrosarcoma (mTOR) pathway activation in the tumor, targeted therapy was applied resulting in complete remission of disease. Although the PI3K/AKT/mTOR signaling pathway plays a role in MB, we did not find TSC1/TSC2 (TSC, tuberous sclerosis complex) mutation in our patient. We speculate that a different pathway resulting in mTOR activation is the basis of both TSC and MB in this child; H&E, haematoxilin and eosin; Gd, gadolinium.