Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 56
Filtrar
Más filtros

Tipo del documento
Intervalo de año de publicación
1.
Oncologist ; 29(2): 106-116, 2024 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-37878787

RESUMEN

Rare cancers and other rare nonmalignant tumors comprise 25% of all cancer diagnoses and account for 25% of all cancer deaths. They are difficult to study due to many factors, including infrequent occurrence, lack of a universal infrastructure for data and/or tissue collection, and a paucity of disease models to test potential treatments. For each individual rare cancer, the limited number of diagnosed cases makes it difficult to recruit sufficient patients for clinical studies, and rare cancer research studies are often siloed. As a result, progress has been slow for many of these cancers. While rare cancer research efforts have increased over time, the breadth of the research landscape is not known. A recent literature search revealed a sharp increase in rare tumor, and rare cancer publications began in the early 2000s. To identify rare cancer research efforts being conducted in the US and globally, we conducted an online search of rare tumor/rare cancer research programs and identified 76 programs. To gain a deeper understanding of these programs, we composed and conducted a survey to ask programs for details about their research efforts. Of the 42 programs contacted to complete the survey, 23 programs responded. Survey results show most programs are collecting clinical data, molecular data, and biospecimens, and many are conducting molecular analyses. This landscape analysis demonstrates that multiple rare cancer research efforts are ongoing, and the rare cancer community may benefit from collaboration among stakeholders to accelerate research and improve patient outcomes.


Asunto(s)
Neoplasias , Humanos , Bancos de Tejidos
2.
Future Oncol ; 20(14): 877-890, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38869947

RESUMEN

WHAT IS THIS SUMMARY ABOUT?: This summary describes a publication about a study called SPRINT. The SPRINT study included 50 children with neurofibromatosis type 1 (NF1) and plexiform neurofibroma (PN) that could not be removed with surgery. PNs are tumors that grow along nerves and can cause various problems for children, such as pain, changes to appearance, and muscle weakness. In SPRINT, the study team wanted to learn whether a medication called selumetinib was able to shrink the PN caused by NF1 (also known as NF1-related PN), and if shrinking PNs helped relieve children of the problems caused by it. To assess how selumetinib might help, children had scans to measure the size of their PN, completed questionnaires, and had a variety of other tests done by their doctor. Their caregivers also completed questionnaires about their child. The children took selumetinib capsules twice a day on an empty stomach. WHAT WERE THE RESULTS?: The results showed that selumetinib was able to shrink the PN for most children (68%). The results also showed that the problems caused by the children's PNs mostly improved while on selumetinib treatment. SPRINT also showed that the side effects of selumetinib were mainly mild and could be managed by doctors. WHAT DO THE RESULTS MEAN?: Before SPRINT, there were not many treatment options for children with NF1 and PN as there were no medications that had been shown to shrink PN, and surgery was not always possible. SPRINT showed that this medication shrinks most PNs and could help children with NF1 and PN. In April 2020, selumetinib was approved by the US Food and Drug Administration (FDA) because of the results of SPRINT. Selumetinib was the first and, as of February 2024, is the only medicine that can be prescribed by doctors to help children with NF1-related PN. Clinical Trial Registration: NCT01362803 (SPRINT) (ClinicalTrials.gov).


Asunto(s)
Bencimidazoles , Neurofibroma Plexiforme , Neurofibromatosis 1 , Adolescente , Niño , Preescolar , Femenino , Humanos , Masculino , Bencimidazoles/uso terapéutico , Bencimidazoles/efectos adversos , Neurofibroma Plexiforme/tratamiento farmacológico , Neurofibroma Plexiforme/patología , Neurofibromatosis 1/tratamiento farmacológico , Neurofibromatosis 1/complicaciones , Inhibidores de Proteínas Quinasas/uso terapéutico , Inhibidores de Proteínas Quinasas/efectos adversos , Resultado del Tratamiento
3.
Clin Trials ; 21(2): 189-198, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-37877369

RESUMEN

BACKGROUND/AIMS: We developed an observer disfigurement severity scale for neurofibroma-related plexiform neurofibromas to assess change in plexiform neurofibroma-related disfigurement and evaluated its feasibility, reliability, and validity. METHODS: Twenty-eight raters, divided into four cohorts based on neurofibromatosis type 1 familiarity and clinical experience, were shown photographs of children in a clinical trial (NCT01362803) at baseline and 1 year on selumetinib treatment for plexiform neurofibromas (n = 20) and of untreated participants with plexiform neurofibromas (n = 4). Raters, blinded to treatment and timepoint, completed the 0-10 disfigurement severity score for plexiform neurofibroma on each image (0 = not at all disfigured, 10 = very disfigured). Raters evaluated the ease of completing the scale, and a subset repeated the procedure to assess intra-rater reliability. RESULTS: Mean baseline disfigurement severity score for plexiform neurofibroma ratings were similar for the selumetinib group (6.23) and controls (6.38). Mean paired differences between pre- and on-treatment ratings was -1.01 (less disfigurement) in the selumetinib group and 0.09 in the control (p = 0.005). For the disfigurement severity score for plexiform neurofibroma ratings, there was moderate-to-substantial agreement within rater cohorts (weighted kappa range = 0.46-0.66) and agreement between scores of the same raters at repeat sessions (p > 0.05). In the selumetinib group, change in disfigurement severity score for plexiform neurofibroma ratings was moderately correlated with change in plexiform neurofibroma volume with treatment (r = 0.60). CONCLUSION: This study demonstrates that our observer-rated disfigurement severity score for plexiform neurofibroma was feasible, reliable, and documented improvement in disfigurement in participants with plexiform neurofibroma shrinkage. Prospective studies in larger samples are needed to validate this scale further.


Asunto(s)
Neurofibroma Plexiforme , Neurofibromatosis 1 , Niño , Humanos , Neurofibroma Plexiforme/tratamiento farmacológico , Neurofibromatosis 1/tratamiento farmacológico , Estudios Prospectivos , Reproducibilidad de los Resultados
4.
Clin Trials ; 21(1): 29-39, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-37772407

RESUMEN

Neurofibromatosis type 1 is a genetic syndrome characterized by a wide variety of tumor and non-tumor manifestations. Bone-related issues, such as scoliosis, tibial dysplasia, and low bone mineral density, are a significant source of morbidity for this population with limited treatment options. Some of the challenges to developing such treatments include the lack of consensus regarding the optimal methods to assess bone health in neurofibromatosis type 1 and limited data regarding the natural history of these manifestations. In this review, the Functional Committee of the Response Evaluation in Neurofibromatosis and Schwannomatosis International Collaboration: (1) presents the available techniques for measuring overall bone health and metabolism in persons with neurofibromatosis type 1, (2) reviews data for use of each of these measures in the neurofibromatosis type 1 population, and (3) describes the strengths and limitations for each method as they might be used in clinical trials targeting neurofibromatosis type 1 bone manifestations. The Response Evaluation in Neurofibromatosis and Schwannomatosis International Collaboration supports the development of a prospective, longitudinal natural history study focusing on the bone-related manifestations and relevant biomarkers of neurofibromatosis type 1. In addition, we suggest that the neurofibromatosis type 1 research community consider adding the less burdensome measurements of bone health as exploratory endpoints in ongoing or planned clinical trials for other neurofibromatosis type 1 manifestations to expand knowledge in the field.


Asunto(s)
Neurilemoma , Neurofibromatosis , Neurofibromatosis 1 , Neoplasias Cutáneas , Humanos , Neurofibromatosis 1/complicaciones , Neurofibromatosis 1/terapia , Densidad Ósea/fisiología , Estudios Prospectivos , Neurofibromatosis/complicaciones , Neurofibromatosis/terapia
5.
N Engl J Med ; 382(15): 1430-1442, 2020 04 09.
Artículo en Inglés | MEDLINE | ID: mdl-32187457

RESUMEN

BACKGROUND: No approved therapies exist for inoperable plexiform neurofibromas in patients with neurofibromatosis type 1. METHODS: We conducted an open-label, phase 2 trial of selumetinib to determine the objective response rate among patients with plexiform neurofibromas and to assess clinical benefit. Children with neurofibromatosis type 1 and symptomatic inoperable plexiform neurofibromas received oral selumetinib twice daily at a dose of 25 mg per square meter of body-surface area on a continuous dosing schedule (28-day cycles). Volumetric magnetic resonance imaging and clinical outcome assessments (pain, quality of life, disfigurement, and function) were performed at least every four cycles. Children rated tumor pain intensity on a scale from 0 (no pain) to 10 (worst pain imaginable). RESULTS: A total of 50 children (median age, 10.2 years; range, 3.5 to 17.4) were enrolled from August 2015 through August 2016. The most frequent neurofibroma-related symptoms were disfigurement (44 patients), motor dysfunction (33), and pain (26). A total of 35 patients (70%) had a confirmed partial response as of March 29, 2019, and 28 of these patients had a durable response (lasting ≥1 year). After 1 year of treatment, the mean decrease in child-reported tumor pain-intensity scores was 2 points, considered a clinically meaningful improvement. In addition, clinically meaningful improvements were seen in child-reported and parent-reported interference of pain in daily functioning (38% and 50%, respectively) and overall health-related quality of life (48% and 58%, respectively) as well as in functional outcomes of strength (56% of patients) and range of motion (38% of patients). Five patients discontinued treatment because of toxic effects possibly related to selumetinib, and 6 patients had disease progression. The most frequent toxic effects were nausea, vomiting, or diarrhea; an asymptomatic increase in the creatine phosphokinase level; acneiform rash; and paronychia. CONCLUSIONS: In this phase 2 trial, most children with neurofibromatosis type 1 and inoperable plexiform neurofibromas had durable tumor shrinkage and clinical benefit from selumetinib. (Funded by the Intramural Research Program of the National Institutes of Health and others; ClinicalTrials.gov number, NCT01362803.).


Asunto(s)
Bencimidazoles/uso terapéutico , Quinasas de Proteína Quinasa Activadas por Mitógenos/antagonistas & inhibidores , Neurofibroma Plexiforme/tratamiento farmacológico , Neurofibromatosis 1/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/uso terapéutico , Adolescente , Bencimidazoles/efectos adversos , Niño , Preescolar , Femenino , Humanos , Masculino , Náusea/inducido químicamente , Neurofibroma Plexiforme/complicaciones , Neurofibroma Plexiforme/patología , Neurofibromatosis 1/complicaciones , Neurofibromatosis 1/patología , Dolor/etiología , Medición de Resultados Informados por el Paciente , Supervivencia sin Progresión , Inhibidores de Proteínas Quinasas/efectos adversos , Carga Tumoral/efectos de los fármacos
6.
J Antimicrob Chemother ; 78(3): 719-723, 2023 03 02.
Artículo en Inglés | MEDLINE | ID: mdl-36640136

RESUMEN

OBJECTIVES: NDM-producing Enterobacterales (NDME) account for 34.9% of new carbapenemase-producing Enterobacterales cases in Israeli hospitals. The goals of this study were to characterize the genomic composition of NDME isolates and mobile genetic elements (MGEs) and to identify NDME transmission events (TEs). METHODS: The study was conducted at the Tel-Aviv Sourasky, Rambam and Sha'are-Zedek Medical Centers (TASMC, RMC and SZMC, respectively). All NDME isolates detected between January 2018 and July 2019 were included.Phylogenetic analysis was based on core-genome SNP distances. Core-genome distance of ≤5 SNPs between isolates from patients with overlapping hospitalization periods was suggestive of a potential TE. MGEs were classified by comparison of the blaNDM gene flanking regions. RESULTS: The study included 212 NDME isolates from 203 patients, including 104 isolates from TASMC, 30 isolates from RMC and 78 isolates from SZMC. The majority of isolates (n = 157; 74%) harboured the blaNDM-1 gene, followed by the blaNDM-5 (n = 48) and blaNDM-15 genes (n = 7). The most common NDME species were Klebsiella pneumoniae (n = 67), Escherichia coli (n = 65) and Enterobacter cloacae (n = 45), all showing a highly diverse clonal structure. Most blaNDM-1-harbouring isolates (134/157; 85%) were divided into nine different MGE modules, variably distributed across species and hospitals.The numbers of post-admission acquisition cases (n = 118) that could be linked to other cases by both molecular and epidemiological criteria were 13/58 (24.2%), 3/48 (6.3%) and 4/12 (33.3%) in TASMC, SZMC and RMC, respectively. CONCLUSIONS: The study depicted a complex and diverse population structure, suggesting that NDME had not spread via clonal expansion.


Asunto(s)
Antibacterianos , beta-Lactamasas , Humanos , Filogenia , Israel/epidemiología , beta-Lactamasas/genética , Proteínas Bacterianas/genética , Hospitales , Klebsiella pneumoniae/genética , Escherichia coli/genética , Pruebas de Sensibilidad Microbiana , Plásmidos
7.
Ann Clin Microbiol Antimicrob ; 22(1): 52, 2023 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-37391819

RESUMEN

BACKGROUND: NDM-producing Acinetobacter baumannii (NDMAb) were reported sporadically worldwide but little is known about the transmission, epidemiology and clinical features of NDMAb-infected patients. The goals of this study were to characterize (1) the epidemiology and clinical features of NDMAb-infected patients; (2) the microbiological and molecular features of NDMAb isolates and (3) the transmission networks of NDMAb within healthcare facilities. METHODS: The study was conducted at the Tel-Aviv Sourasky, Rambam and Sha'are-Zedek Medical centers (TASMC, RMC and SZMC, respectively) in Israel. All cases detected between January 2018 and July 2019 were included. Phylogenetic analysis was based on core genome SNP distances. Clonal transmission was defined according to molecular (≤ 5 SNP) and epidemiological criteria (overlapping hospital stay). NDMAb cases were compared at a ratio of 1:2 with non-NDM carbapenem-resistant A. baumannii (CRAb) cases. RESULTS: The study included 54 NDMAb-positive out of 857 CRAb patients, including 6/179 (3.3%) in TASMC, 18/441 (4.0%) in SZMC and 30/237 (12.6%) in RMC. Patients infected by NDMAb had similar clinical features and risk factors as patients with non-NDM CRAb. The length-of-stay was higher in NDMAb cases (48.5 days vs. 36 days, respectively, p = 0.097) and the in-hospital mortality was similarly high in both groups. Most isolates (41/54, 76%) were first detected from surveillance culture. The majority of isolates harbored the blaNDM-2 gene allele (n = 33), followed by the blaNDM-1 (n = 20) allele and the blaNDM-4 allele (n = 1). The majority of isolates were related within the ST level to other isolates in SZMC and RMC: 17/18 and 27/30 isolates, respectfully. The common ST's were the blaNDM-1 harboring ST-2 (n = 3) and ST-107 (n = 8) in SZMC and the blaNDM-2 harboring ST-103 in SZMC (n = 6) and in RMC (n = 27). All blaNDM alleles were located within a conserved mobile genetic environment flanked by the ISAb125 and IS91 family transposon. Clonal transmission was identified in most hospital-acquired cases in RMC and SZMC. CONCLUSION: NDMAb constitutes a minor part of CRAb cases and are clinically similar to non-NDM CRAb. Transmission of NDMAb occurs mostly by clonal spread.


Asunto(s)
Acinetobacter baumannii , Humanos , Israel/epidemiología , Acinetobacter baumannii/genética , Filogenia , Alelos , Carbapenémicos/farmacología
8.
J Pediatr Orthop ; 43(7): e531-e537, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37253707

RESUMEN

BACKGROUND: Spinal conditions, such as scoliosis and spinal tumors, are prevalent in neurofibromatosis type 1 (NF1). Despite the recognized importance of their early detection and treatment, there remain knowledge gaps in how to approach these manifestations. The purpose of this study was to utilize the experience of a multidisciplinary committee of experts to establish consensus-based best practice guidelines (BPGs) for spinal screening and surveillance, surgical intervention, and medical therapy in pediatric patients with NF1. METHODS: Using the results of a prior systematic review, 10 key questions that required further assessment were first identified. A committee of 20 experts across medical specialties was then chosen based on their clinical experience with spinal deformity and tumors in NF1. These were 9 orthopaedic surgeons, 4 neuro-oncologists/oncologists, 3 neurosurgeons, 2 neurologists, 1 pulmonologist, and 1 clinical geneticist. An initial online survey on current practices and opinions was conducted, followed by 2 additional surveys via a formal consensus-based modified Delphi method. The final survey involved voting on agreement or disagreement with 35 recommendations. Items reaching consensus (≥70% agreement or disagreement) were included in the final BPGs. RESULTS: Consensus was reached for 30 total recommendations on the management of spinal deformity and tumors in NF1. These were 11 recommendations on screening and surveillance, 16 on surgical intervention, and 3 on medical therapy. Five recommendations did not achieve consensus and were excluded from the BPGs. CONCLUSION: We present a set of consensus-based BPGs comprised of 30 recommendations for spinal screening and surveillance, surgical intervention, and medical therapy in pediatric NF1.


Asunto(s)
Neurofibromatosis 1 , Escoliosis , Niño , Humanos , Neurofibromatosis 1/complicaciones , Neurofibromatosis 1/diagnóstico , Neurofibromatosis 1/terapia , Consenso , Escoliosis/terapia , Escoliosis/cirugía , Columna Vertebral , Técnica Delphi
9.
Am J Med Genet C Semin Med Genet ; 190(4): 530-540, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36533693

RESUMEN

RASopathies are a set of clinical syndromes that have molecular and clinical overlap. Genetically, these syndromes are defined by germline pathogenic variants in RAS/MAPK pathway genes resulting in activation of this pathway. Clinically, their common molecular signature leads to comparable phenotypes, including cardiac anomalies, neurologic disorders and notably, elevated cancer risk. Cancer risk in individuals with RASopathies has been estimated from retrospective reviews and cohort studies. For example, in Costello syndrome, cancer incidence is significantly elevated over the general population, largely due to solid tumors. In some forms of Noonan syndrome, cancer risk is also elevated over the general population and is enriched for hematologic malignancies. Thus, cancer surveillance guidelines have been developed to monitor for the occurrence of such cancers in individuals with some RASopathies. These include abdominal ultrasound and urinalyses for individuals with Costello syndrome, while complete blood counts and splenic examination are recommended in Noonan syndrome. Improved cancer risk estimates and refinement of surveillance recommendations will improve the care of individuals with RASopathies.


Asunto(s)
Síndrome de Costello , Neoplasias , Síndrome de Noonan , Humanos , Síndrome de Noonan/epidemiología , Síndrome de Noonan/genética , Síndrome de Noonan/patología , Síndrome de Costello/epidemiología , Síndrome de Costello/genética , Incidencia , Estudios Retrospectivos , Proteínas ras/genética , Neoplasias/epidemiología , Neoplasias/genética
10.
Support Care Cancer ; 30(4): 3513-3520, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35018520

RESUMEN

PURPOSE: Chemotherapy-induced nausea and vomiting (CINV) is a frequently seen burdensome adverse event of cancer therapy. The 5-HT3 receptor antagonist ondansetron has improved the rates of CINV but, unfortunately, up to 30% of patients do not obtain satisfactory control. This study examined whether genetic variations in a relevant drug-metabolizing enzyme (CYP2D6), transporter (ABCB1), or receptor (5-HT3) were associated with ondansetron failure. METHODS: DNA was extracted from blood and used to genotype: ABCB1 (3435C > T (rs1045642) and G2677A/T (rs2032582)), 5-HT3RB (rs3758987 T > C and rs45460698 (delAAG/dupAAG)), and CYP2D6 variants. Ondansetron failure was determined by review of the medical records and by patient-reported outcomes (PROs). RESULTS: One hundred twenty-nine patients were approached; 103 consented. Participants were less than 1 to 33 years (mean 6.85). A total of 39.8% was female, 58.3% was White (22.3% Black, 19.4% other), and 24.3% was Hispanic. A majority had leukemia or lymphoma, and 41 (39.8%) met the definition of ondansetron failure. Of variants tested, rs45460698 independently showed a significant difference in risk of ondansetron failure between a mutant (any deletion) and normal allele (p = 0.0281, OR 2.67). Age and BMI were both predictive of ondansetron failure (age > 12 (OR 1.12, p = 0.0012) and higher BMI (OR 1.13, p = 0.0119)). In multivariate analysis, age > 12 was highly predictive of ondansetron failure (OR 7.108, p = 0.0008). rs45460698 was predictive when combined with an increased nausea phenotype variant of rs1045642 (OR 3.45, p = 0.0426). CONCLUSION: Select phenotypes of 5-HT3RB and ABCB1, age, and potentially BMI can help predict increased risk for CINV in a diverse pediatric oncology population.


Asunto(s)
Antieméticos , Neoplasias , Antieméticos/efectos adversos , Femenino , Humanos , Náusea/tratamiento farmacológico , Neoplasias/complicaciones , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Ondansetrón/efectos adversos , Farmacogenética , Vómitos/tratamiento farmacológico
11.
J Pediatr Orthop ; 41(1): e90-e93, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32852366

RESUMEN

Congenital tibial pseudarthrosis is a rare condition seen in neurofibromatosis type 1 (NF1), and treatment is complex. A randomized, placebo-controlled trial of bone morphogenetic protein (rhBMP-2; INFUSE bone graft) at time of tibial surgery was developed by the Neurofibromatosis Clinical Trials Consortium. Patients were randomized to receive rhBMP-2 that would, or would not, be added to the standard surgical procedure consisting of resection of pseudarthrosis tissue, insertion of a rigid intramedullary rod, and placement of autogenous iliac crest bone graft. Despite involvement of 16 centers with wide experience with NF1 orthopaedic management, only 5 patients (of 54 required) were able to be enrolled in the study during a 3-year time period. Because of the inability to recruit sufficient patients, this study was closed in June 2019, with plans to terminate. The obstacles that were encountered during the study are summarized. The authors question whether a randomized, placebo-controlled trial of a rare pediatric orthopaedic condition is possible to accomplish. Recommendations are provided to guide future studies of orthopaedic manifestations of NF1.Level of Evidence: Level V.


Asunto(s)
Proteína Morfogenética Ósea 2/farmacología , Neurofibromatosis 1/cirugía , Procedimientos Ortopédicos/métodos , Selección de Paciente , Seudoartrosis , Ensayos Clínicos Controlados Aleatorios como Asunto/métodos , Factor de Crecimiento Transformador beta/farmacología , Proteínas Morfogenéticas Óseas/farmacología , Humanos , Neurofibromatosis 1/complicaciones , Seudoartrosis/congénito , Seudoartrosis/cirugía , Enfermedades Raras , Proteínas Recombinantes/farmacología , Tamaño de la Muestra , Tibia/anomalías , Tibia/cirugía
12.
J Synchrotron Radiat ; 27(Pt 5): 1415-1429, 2020 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-32876619

RESUMEN

BioMAX is the first macromolecular crystallography beamline at the MAX IV Laboratory 3 GeV storage ring, which is the first operational multi-bend achromat storage ring. Due to the low-emittance storage ring, BioMAX has a parallel, high-intensity X-ray beam, even when focused down to 20 µm × 5 µm using the bendable focusing mirrors. The beam is tunable in the energy range 5-25 keV using the in-vacuum undulator and the horizontally deflecting double-crystal monochromator. BioMAX is equipped with an MD3 diffractometer, an ISARA high-capacity sample changer and an EIGER 16M hybrid pixel detector. Data collection at BioMAX is controlled using the newly developed MXCuBE3 graphical user interface, and sample tracking is handled by ISPyB. The computing infrastructure includes data storage and processing both at MAX IV and the Lund University supercomputing center LUNARC. With state-of-the-art instrumentation, a high degree of automation, a user-friendly control system interface and remote operation, BioMAX provides an excellent facility for most macromolecular crystallography experiments. Serial crystallography using either a high-viscosity extruder injector or the MD3 as a fixed-target scanner is already implemented. The serial crystallography activities at MAX IV Laboratory will be further developed at the microfocus beamline MicroMAX, when it comes into operation in 2022. MicroMAX will have a 1 µm × 1 µm beam focus and a flux up to 1015 photons s-1 with main applications in serial crystallography, room-temperature structure determinations and time-resolved experiments.

13.
Genet Med ; 22(11): 1786-1793, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32601387

RESUMEN

PURPOSE: Plexiform neurofibromas (pNF) develop in children with neurofibromatosis type 1 (NF1) and can be associated with several skeletal comorbidities. Preclinical mouse studies revealed Nf1 deficiency in osteoprogenitor cells disrupts, in a MEK-dependent manner, pyrophosphate (PPi) homeostasis and skeletal mineralization. The etiology of NF-associated skeletal manifestations remains unknown. METHODS: We used mouse models of NF1 neurofibromas to assess bone mineralization of skeletal structures adjacent to tumors. Expression of genes involved in pyrophosphate homeostasis was assessed in mouse and human NF tumors and Schwann cell cultures. We used dual-energy X-ray absorptiometry (DXA) to assess tumor-associated changes in bone mineral density (BMD) in an individual with NF1 following treatment with the MEK inhibitor selumetinib. RESULTS: We detected increased nonmineralized bone surfaces adjacent to tumors in mouse models of NF1 neurofibromas. Expression of Enpp1, a PPi-generating ectophosphatase, and ANKH, a PPi transporter, was increased in mouse and human neurofibroma-derived tissues and Schwann cells, respectively. In one patient, tumor-associated reductions in BMD were partially rescued following therapy with selumetinib. CONCLUSION: Results indicate that NF-associated skeletal pathologies in NF1 are associated with dysregulated pyrophosphate homeostasis in adjacent NF tumors and suggest that treatment of NFs with MEK inhibitors may improve skeletal manifestations of the disease.


Asunto(s)
Neurofibroma Plexiforme , Neurofibroma , Neurofibromatosis 1 , Animales , Humanos , Ratones , Neurofibroma Plexiforme/genética , Neurofibromatosis 1/genética , Inhibidores de Proteínas Quinasas , Células de Schwann
14.
Am J Med Genet A ; 182(4): 866-876, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31913576

RESUMEN

RASopathies caused by germline pathogenic variants in genes that encode RAS pathway proteins. These disorders include neurofibromatosis type 1 (NF1), Noonan syndrome (NS), cardiofaciocutaneous syndrome (CFC), and Costello syndrome (CS), and others. RASopathies are characterized by heterogenous manifestations, including congenital heart disease, failure to thrive, and increased risk of cancers. Previous work led by the NCI Pediatric Oncology Branch has altered the natural course of one of the key manifestations of the RASopathy NF1. Through the conduct of a longitudinal cohort study and early phase clinical trials, the MEK inhibitor selumetinib was identified as the first active therapy for the NF1-related peripheral nerve sheath tumors called plexiform neurofibromas (PNs). As a result, selumetinib was granted breakthrough therapy designation by the FDA for the treatment of PN. Other RASopathy manifestations may also benefit from RAS targeted therapies. The overall goal of Advancing RAS/RASopathy Therapies (ART), a new NCI initiative, is to develop effective therapies and prevention strategies for the clinical manifestations of the non-NF1 RASopathies and for tumors characterized by somatic RAS mutations. This report reflects discussions from a February 2019 initiation meeting for this project, which had broad international collaboration from basic and clinical researchers and patient advocates.


Asunto(s)
Síndrome de Costello/terapia , Displasia Ectodérmica/terapia , Insuficiencia de Crecimiento/terapia , Cardiopatías Congénitas/terapia , Terapia Molecular Dirigida , Mutación , Neurofibromatosis 1/terapia , Síndrome de Noonan/terapia , Proteínas ras/antagonistas & inhibidores , Biomarcadores de Tumor/antagonistas & inhibidores , Biomarcadores de Tumor/genética , Síndrome de Costello/genética , Síndrome de Costello/patología , Displasia Ectodérmica/genética , Displasia Ectodérmica/patología , Facies , Insuficiencia de Crecimiento/genética , Insuficiencia de Crecimiento/patología , Cardiopatías Congénitas/genética , Cardiopatías Congénitas/patología , Humanos , Colaboración Intersectorial , National Cancer Institute (U.S.) , Neurofibromatosis 1/genética , Neurofibromatosis 1/patología , Síndrome de Noonan/genética , Síndrome de Noonan/patología , Informe de Investigación , Transducción de Señal , Estados Unidos , Proteínas ras/genética
15.
Am J Med Genet A ; 182(3): 597-606, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31825160

RESUMEN

The RASopathies are a group of genetic disorders that result from germline pathogenic variants affecting RAS-mitogen activated protein kinase (MAPK) pathway genes. RASopathies share RAS/MAPK pathway dysregulation and share phenotypic manifestations affecting numerous organ systems, causing lifelong and at times life-limiting medical complications. RASopathies may benefit from precision medicine approaches. For this reason, the Sixth International RASopathies Symposium focused on exploring precision medicine. This meeting brought together basic science researchers, clinicians, clinician scientists, patient advocates, and representatives from pharmaceutical companies and the National Institutes of Health. Novel RASopathy genes, variants, and animal models were discussed in the context of medication trials and drug development. Attempts to define and measure meaningful endpoints for treatment trials were discussed, as was drug availability to patients after trial completion.


Asunto(s)
Enfermedades Genéticas Congénitas/genética , Quinasas de Proteína Quinasa Activadas por Mitógenos/genética , Proteínas ras/genética , Enfermedades Genéticas Congénitas/patología , Mutación de Línea Germinal/genética , Humanos , Transducción de Señal/genética
16.
J Pathol ; 248(4): 421-437, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-30982971

RESUMEN

Tspan8 exhibits a functional role in many cancer types including pancreatic, colorectal, oesophagus carcinoma, and melanoma. We present a first study on the expression and function of Tspan8 in breast cancer. Tspan8 protein was present in the majority of human primary breast cancer lesions and metastases in the brain, bone, lung, and liver. In a syngeneic rat breast cancer model, Tspan8+ tumours formed multiple liver and spleen metastases, while Tspan8- tumours exhibited a significantly diminished ability to metastasise, indicating a role of Tspan8 in metastases. Addressing the underlying molecular mechanisms, we discovered that Tspan8 can mediate up-regulation of E-cadherin and down-regulation of Twist, p120-catenin, and ß-catenin target genes accompanied by the change of cell phenotype, resembling the mesenchymal-epithelial transition. Furthermore, Tspan8+ cells exhibited enhanced cell-cell adhesion, diminished motility, and decreased sensitivity to irradiation. As a regulator of the content and function of extracellular vesicles (EVs), Tspan8 mediated a several-fold increase in EV number in cell culture and the circulation of tumour-bearing animals. We observed increased protein levels of E-cadherin and p120-catenin in these EVs; furthermore, Tspan8 and p120-catenin were co-immunoprecipitated, indicating that they may interact with each other. Altogether, our findings show the presence of Tspan8 in breast cancer primary lesion and metastases and indicate its role as a regulator of cell behaviour and EV release in breast cancer. © 2019 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.


Asunto(s)
Neoplasias de la Mama/metabolismo , Cadherinas/metabolismo , Carcinoma Ductal de Mama/metabolismo , Carcinoma Intraductal no Infiltrante/metabolismo , Carcinoma Lobular/metabolismo , Tetraspaninas/metabolismo , Animales , Biomarcadores de Tumor/metabolismo , Neoplasias de la Mama/patología , Carcinoma Ductal de Mama/patología , Carcinoma Intraductal no Infiltrante/patología , Carcinoma Lobular/patología , Línea Celular Tumoral , Vesículas Extracelulares , Femenino , Humanos , Metástasis de la Neoplasia , Ratas , Transducción de Señal
17.
J Pediatr Hematol Oncol ; 42(5): e361-e364, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-30969264

RESUMEN

Cutaneous T-cell lymphomas are very rare in children. Although mycosis fungoides is the most common of these rare cutaneous T-cell lymphomas in children, transformation to an aggressive malignancy remains extremely uncommon, and there are no clear guidelines for clinical management in the pediatric population. In addition, the increased usage of next-generation sequencing for pediatric patients with unusual malignancies may result in the discovery of pathogenic germline mutations, though the association between these mutations and the patient's cancer is not always clear. We present here a unique pediatric case of transformed mycosis fungoides in a patient with BRCA2 mutation.


Asunto(s)
Proteína BRCA2/genética , Linfoma Cutáneo de Células T/patología , Mutación , Micosis Fungoide/patología , Neoplasias Cutáneas/patología , Preescolar , Femenino , Humanos , Linfoma Cutáneo de Células T/complicaciones , Linfoma Cutáneo de Células T/genética , Micosis Fungoide/complicaciones , Micosis Fungoide/genética , Pronóstico , Neoplasias Cutáneas/complicaciones , Neoplasias Cutáneas/genética
18.
Childs Nerv Syst ; 36(10): 2443-2452, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32607696

RESUMEN

BACKGROUND: Neurofibromatosis type 1 (NF1)-related plexiform neurofibromas (pNF) can be debilitating and until recently, surgery was the only potentially effective therapy for these tumors. METHODS: We review critical steps in the path towards the FDA approval of the first medical therapy for NF1 pNF and the current status of MEK inhbitor therapy. RESULTS: Sustained efforts by the NF community have resulted in a detailed understanding of the natural history and biology of NF1-related peripheral nerve sheath tumors. This work provided the basis for the development of meaningful clinical trials targeting pNF. Inhibition of the RAS/MAPK signaling pathway with MEK inhibitors identified the first medical therapy which resulted in shrinkage in the majority of children with NF1 and large inoperable pNF. Based on this finding and subsequent demonstration of clinical benefit, the MEK inhibitor selumetinib recently received approval by the United States Food and Drug Administration (FDA) for children with symptomatic pNF. CONCLUSIONS: Sustained efforts and collaborations have resulted in identification of MEK inhibitors as effective therapy for NF1 pNF. Future work work will be directed at prevention of pNF morbidity and deepening the reponse in symptomatic pNF.


Asunto(s)
Neoplasias de la Vaina del Nervio , Neurofibroma Plexiforme , Neurofibromatosis 1 , Niño , Humanos , Quinasas de Proteína Quinasa Activadas por Mitógenos , Neurofibroma Plexiforme/tratamiento farmacológico , Neurofibromatosis 1/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/uso terapéutico
19.
J Antimicrob Chemother ; 74(12): 3473-3480, 2019 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-31504593

RESUMEN

BACKGROUND: Infection and colonization with multi-resistant Acinetobacter baumannii causes therapeutic and economic problems in the nosocomial setting. Due to the sensitivity issue of screening schemes for A. baumannii, it is difficult to implement adequate transmission prevention measures. The high discriminatory power of WGS for transmission-chain analysis provides us with the necessary tool to study and identify transmission events. We retrospectively sequenced and analysed 39 A. baumannii isolates from 2012-15 to search for possible missed transmission events. METHODS: Molecular typing by WGS was performed for non-repetitive (n=39) carbapenem-resistant A. baumannii. Retrospective assessment of patient records was performed to investigate and confirm possible transmission events. RESULTS: Between July 2012 and September 2015, A. baumannii was isolated from 268 patients, of which 16% (42/268) were carbapenem resistant. Thirty-nine of these isolates were recoverable and sequenced. Fifteen percent (6/39) of these were resistant to all antibiotics tested. Most isolates belong to the circulating IC2 clonal type. SNP analysis revealed four potential outbreak clusters. Two of these clusters showed high concordance with the local spatio-temporal epidemiology, suggesting that transmission events were very likely. CONCLUSIONS: Our data suggest that there were two independent transmission events, which would have been missed by conventional MLST owing to high clonality. The routine implementation of WGS can optimize surveillance and initiation of suitable containment measures. In addition, emerging resistance to salvage therapy is a major therapeutic problem and should be monitored closely.


Asunto(s)
Infecciones por Acinetobacter/transmisión , Acinetobacter baumannii/clasificación , Antibacterianos/farmacología , Carbapenémicos/farmacología , Farmacorresistencia Bacteriana Múltiple , Acinetobacter baumannii/efectos de los fármacos , Técnicas de Tipificación Bacteriana , Infección Hospitalaria/microbiología , ADN Bacteriano/genética , Brotes de Enfermedades , Electroforesis en Gel de Campo Pulsado , Femenino , Alemania , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Tipificación de Secuencias Multilocus , Estudios Retrospectivos , Secuenciación Completa del Genoma
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA