Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 163
Filtrar
1.
Genome Biol ; 24(1): 191, 2023 08 28.
Artículo en Inglés | MEDLINE | ID: mdl-37635261

RESUMEN

BACKGROUND: In humans, muscle-invasive bladder cancer (MIBC) is highly aggressive and associated with a poor prognosis. With a high mutation load and large number of altered genes, strategies to delineate key driver events are necessary. Dogs and cats develop urothelial carcinoma (UC) with histological and clinical similarities to human MIBC. Cattle that graze on bracken fern also develop UC, associated with exposure to the carcinogen ptaquiloside. These species may represent relevant animal models of spontaneous and carcinogen-induced UC that can provide insight into human MIBC. RESULTS: Whole-exome sequencing of domestic canine (n = 87) and feline (n = 23) UC, and comparative analysis with human MIBC reveals a lower mutation rate in animal cases and the absence of APOBEC mutational signatures. A convergence of driver genes (ARID1A, KDM6A, TP53, FAT1, and NRAS) is discovered, along with common focally amplified and deleted genes involved in regulation of the cell cycle and chromatin remodelling. We identify mismatch repair deficiency in a subset of canine and feline UCs with biallelic inactivation of MSH2. Bovine UC (n = 8) is distinctly different; we identify novel mutational signatures which are recapitulated in vitro in human urinary bladder UC cells treated with bracken fern extracts or purified ptaquiloside. CONCLUSION: Canine and feline urinary bladder UC represent relevant models of MIBC in humans, and cross-species analysis can identify evolutionarily conserved driver genes. We characterize mutational signatures in bovine UC associated with bracken fern and ptaquiloside exposure, a human-linked cancer exposure. Our work demonstrates the relevance of cross-species comparative analysis in understanding both human and animal UC.


Asunto(s)
Carcinoma de Células Transicionales , Enfermedades de los Gatos , Enfermedades de los Perros , Neoplasias de la Vejiga Urinaria , Humanos , Animales , Gatos , Bovinos , Perros , Neoplasias de la Vejiga Urinaria/genética , Carcinógenos , Músculos
2.
Prosthet Orthot Int ; 46(6): 576-581, 2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-36515903

RESUMEN

BACKGROUND: Patient's acceptance and compliance to spinal orthosis could influence the outcome of orthotic treatment in adolescent idiopathic scoliosis. Two innovative undergarments (thin and thick designs) were designed to improve the patient's orthosis wearing experience and acceptance. OBJECTIVE: This study aimed to evaluate the effects of patients' self-provided undergarment and 2 newly designed undergarments with respect to the orthosis wearing compliance and quality of life (QoL) measures. METHODS: A prospective randomized-controlled study was conducted to compare the effect of three types of undergarments. Thirty-eight subjects with adolescent idiopathic scoliosis were randomly assigned to one of the three groups: self-provided, thin-design, or thick-design undergarment. Wearing compliance logbook, Scoliosis Research Society questionnaire, and Brace Questionnaire were used to document the orthosis wearing period and quantify the health-related and orthosis-related QoL measures. Kruskal-Wallis one-way analysis of variance (ANOVA) and Friedman two-way ANOVA by ranks tests were conducted for intergroup and intragroup comparisons, respectively. RESULTS: The compliance and QoL domains of the subjects in the thin-design undergarment group were significantly higher than those of the other two undergarment groups (P < .05). The intragroup compliance and QoL scores varied significantly in the 4 visits throughout the study period (P < .05). CONCLUSIONS: It was observed that an adaptation period toward the prescribed spinal orthosis is required to help patients gradually achieve a more stable acceptance. The thin-design undergarment was ranked higher than the other two tested undergarments in compliance and QoL measures.


Asunto(s)
Cifosis , Escoliosis , Humanos , Adolescente , Escoliosis/terapia , Calidad de Vida , Estudios Prospectivos , Tirantes , Cooperación del Paciente , Aparatos Ortopédicos
3.
Sci Adv ; 8(42): eabq8297, 2022 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-36269833

RESUMEN

Fumarate hydratase (FH) is a mitochondrial enzyme that catalyzes the reversible hydration of fumarate to malate in the tricarboxylic acid (TCA) cycle. Germline mutations of FH lead to hereditary leiomyomatosis and renal cell carcinoma (HLRCC), a cancer syndrome characterized by a highly aggressive form of renal cancer. Although HLRCC tumors metastasize rapidly, FH-deficient mice develop premalignant cysts in the kidneys, rather than carcinomas. How Fh1-deficient cells overcome these tumor-suppressive events during transformation is unknown. Here, we perform a genome-wide CRISPR-Cas9 screen to identify genes that, when ablated, enhance the proliferation of Fh1-deficient cells. We found that the depletion of the histone cell cycle regulator (HIRA) enhances proliferation and invasion of Fh1-deficient cells in vitro and in vivo. Mechanistically, Hira loss activates MYC and its target genes, increasing nucleotide metabolism specifically in Fh1-deficient cells, independent of its histone chaperone activity. These results are instrumental for understanding mechanisms of tumorigenesis in HLRCC and the development of targeted treatments for patients.

4.
JAMA Netw Open ; 5(3): e223862, 2022 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-35333363

RESUMEN

Importance: Diabetic kidney disease (DKD) and its comorbidities can be prevented by treating multiple targets. Technology-assisted team-based care with regular feedback and patient empowerment can improve the attainment of multiple targets and clinical outcomes in patients with type 2 diabetes, but the effects of this intervention on patients with DKD are unclear. Objective: To evaluate the effect of the Joint Asia Diabetes Evaluation (JADE) web portal, nurse reminders, and team-based care on multiple risk factors in patients with DKD. Design, Setting, and Participants: This 12-month multinational, open-label randomized clinical trial was conducted between June 27, 2014, and February 19, 2019, at 13 hospital-based diabetes centers in 8 countries or regions in Asia. All patients who participated had DKD. The intention-to-treat data analysis was performed from April 7 to June 30, 2020. Interventions: Patients were randomized in a 1:1:1 ratio at each site to usual care, empowered care, or team-based empowered care. All patients underwent a JADE web portal-guided structured assessment at baseline and month 12. Patients in the usual care and empowered care groups received a medical follow-up. Patients in the empowered care group also received a personalized JADE report and nurse telephone calls every 3 months. Patients in the team-based empowered care group received additional face-to-face reviews every 3 months from a physician-nurse team. Main Outcomes and Measures: The primary outcome was the proportion of patients who attained multiple treatment targets (defined as ≥3 of 5 targets: HbA1c level <7.0% [53 mmol/mol], blood pressure <130/80 mm Hg, low-density lipoprotein cholesterol level <1.8 mmol/L, triglyceride level <1.7 mmol/L, and/or persistent use of renin-angiotensin-aldosterone system inhibitors). Results: A total of 2393 patients (mean [SD] age, 67.7 [9.8] years; 1267 men [52.9%]) were randomized to the usual care group (n = 795), empowered care group (n = 802), and team-based empowered care group (n = 796). At baseline, 34.7% patients (n = 830) were on 3 treatment targets. On intention-to-treat analysis, the team-based empowered care group had the highest proportion of patients who had further increase in attainment of multiple treatment targets (within-group differences: usual care group, 3.9% [95% CI, 0.0%-7.8%]; empowered care group, 1.3% [95% CI, -2.8% to 5.4%]; team-based empowered care group, 9.1% [95% CI, 4.7%-13.5%]). The team-based empowered care group was more likely to attain multiple treatment targets than the usual care group (risk ratio [RR], 1.17; 95% CI, 1.00-1.37) and the empowered care group (RR, 1.25; 95% CI, 1.06-1.48) after adjustment for site. Compared with the group that did not attain multiple treatment targets, the group that attained multiple treatment targets reported a lower incidence of cardiovascular, kidney, and cancer events (8.4% [n = 51] vs 14.5% [n = 134]; P = .004). Analysis of the per-protocol population yielded similar results. Conclusions and Relevance: This trial found that technology-assisted team-based care for 12 months improved the attainment of multiple treatment targets as well as empowerment in patients with DKD. Trial Registration: ClinicalTrials.gov Identifier: NCT02176278.


Asunto(s)
Diabetes Mellitus Tipo 2 , Nefropatías Diabéticas , Anciano , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/epidemiología , Diabetes Mellitus Tipo 2/terapia , Nefropatías Diabéticas/terapia , Humanos , Internet , Masculino , Factores de Riesgo
5.
Polymers (Basel) ; 14(3)2022 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-35160414

RESUMEN

Conformal cooling channels (CCCs) are widely used in the plastic injection molding process to improve the product quality and operational performance. Tooling that incorporates CCCs can be fabricated through metal additive manufacturing (MAM). The present work focuses on the MAM of a plastic injection mold insert with different CCC types that are circular, serpentine, and tapered channels with/without body-centered cubic (BCC) lattices. The entire manufacturing process of the mold insert is explained from the design step to the final printing step including the computational thermal & mechanical simulations, performance assessments, and multiobjective optimization. Compared to the traditional channels, conformal cooling channels achieved up to 62.9% better cooling performance with a better thermal uniformity on the mold surface. The optimum mold geometry is decided using the multiobjective optimization procedure according to the multiple objectives of cooling time, temperature non-uniformity, and pressure drop in the channel. Direct Metal Laser Sintering (DMLS) method is used for manufacturing the molds and the quality of the printed molds are analyzed with the X-ray Computed Tomography (X-ray CT) technique. The errors between the design and the printed parameters are less than 5% for the circular and tapered channels while the maximum deviation of the strut diameters of the BCC is 0.06 mm.

6.
J Chem Theory Comput ; 18(2): 638-649, 2022 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-35043623

RESUMEN

The weighted ensemble (WE) family of methods is one of several statistical mechanics-based path sampling strategies that can provide estimates of key observables (rate constants and pathways) using a fraction of the time required by direct simulation methods such as molecular dynamics or discrete-state stochastic algorithms. WE methods oversee numerous parallel trajectories using intermittent overhead operations at fixed time intervals, enabling facile interoperability with any dynamics engine. Here, we report on the major upgrades to the WESTPA software package, an open-source, high-performance framework that implements both basic and recently developed WE methods. These upgrades offer substantial improvements over traditional WE methods. The key features of the new WESTPA 2.0 software enhance the efficiency and ease of use: an adaptive binning scheme for more efficient surmounting of large free energy barriers, streamlined handling of large simulation data sets, exponentially improved analysis of kinetics, and developer-friendly tools for creating new WE methods, including a Python API and resampler module for implementing both binned and "binless" WE strategies.

7.
J Med Virol ; 94(2): 771-775, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34708881

RESUMEN

Pteropine orthoreovirus (PRV) is an emerging zoonotic respiratory virus that can be transmitted from bats to humans. In Malaysia, aside from PRV2P (Pulau virus) being isolated from Pteropus hypomelanus sampled in Tioman Island, PRV3M (Melaka virus), PRV4K (Kampar virus), and PRV7S (Sikamat virus) were all isolated from samples of patients who reported having a disease spectrum from acute respiratory distress to influenza-like illness and sometimes even with enteric symptoms such as diarrhea and abdominal pain. Screening of sera collected from human volunteers on Tioman Island in 2001-2002 demonstrated that 12.8% (14/109) were positive for PRV2P and PRV3M. Taking all these together, we aim to investigate the serological prevalence of PRV (including PRV4K and PRV7S) among Tioman Island inhabitants again with the assumption that the seroprevalence rate will remain nearly similar to the above reported if human exposure to bats is still happening in the island. Using sera collected from human volunteers on the same island in 2017, we demonstrated seroprevalence of 17.8% (28/157) against PRV2P and PRV3M, respectively. Seropositivity of 11.4% among Tioman Island inhabitants against PRV4K and PRV7S, respectively, was described in this study. In addition, the seroprevalence of 89.5% (17/19), 73.6% (14/19), 63.0% (12/19), and 73.6% (14/19) against PRV2P, PRV3M, PRV4K, and PRV7S, respectively, were observed among pteropid bats in the island. We revealed that the seroprevalence of PRV among island inhabitants remains nearly similar after nearly two decades, suggesting that potential spill-over events in bat-human interface areas in the Tioman Island. We are unclear whether such spillover was directly from bats to humans, as suspected for the PRV3M human cases, or from an intermediate host(s) yet to be identified. There is a high possibility of the viruses circulating among the bats as demonstrated by high seroprevalence against PRV in the bats.


Asunto(s)
Quirópteros/virología , Orthoreovirus/genética , Orthoreovirus/fisiología , Infecciones por Reoviridae/veterinaria , Zoonosis/transmisión , Adolescente , Adulto , Animales , Anticuerpos Antivirales/sangre , Anticuerpos Antivirales/inmunología , Quirópteros/sangre , Femenino , Voluntarios Sanos , Humanos , Malasia , Masculino , Persona de Mediana Edad , Infecciones por Reoviridae/virología , Estudios Seroepidemiológicos , Adulto Joven , Zoonosis/sangre , Zoonosis/virología
8.
Virus Evol ; 7(2): veab057, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34532060

RESUMEN

The scale of the HIV-1 epidemic underscores the need for a vaccine. The multitude of circulating HIV-1 strains together with HIV-1's high evolvability hints that HIV-1 could adapt to a future vaccine. Here, we wanted to investigate the effect of vaccination on the evolution of the virus post-breakthrough infection. We analyzed 2,635 HIV-1 env sequences sampled up to a year post-diagnosis from 110 vaccine and placebo participants who became infected in the RV144 vaccine efficacy trial. We showed that the Env signature sites that were previously identified to distinguish vaccine and placebo participants were maintained over time. In addition, fewer sites were under diversifying selection in the vaccine group than in the placebo group. These results indicate that HIV-1 would possibly adapt to a vaccine upon its roll-out.

9.
JAMA Netw Open ; 4(8): e2119212, 2021 08 02.
Artículo en Inglés | MEDLINE | ID: mdl-34347060

RESUMEN

Importance: Multidrug-resistant organisms (MDROs) can spread across health care facilities in a region. Because of limited resources, certain interventions can be implemented in only some facilities; thus, decision-makers need to evaluate which interventions may be best to implement. Objective: To identify a group of target facilities and assess which MDRO intervention would be best to implement in the Shared Healthcare Intervention to Eliminate Life-threatening Dissemination of MDROs in Orange County, a large regional public health collaborative in Orange County, California. Design, Setting, and Participants: An agent-based model of health care facilities was developed in 2016 to simulate the spread of methicillin-resistant Staphylococcus aureus (MRSA) and carbapenem-resistant Enterobacteriaceae (CRE) for 10 years starting in 2010 and to simulate the use of various MDRO interventions for 3 years starting in 2017. All health care facilities (23 hospitals, 5 long-term acute care hospitals, and 74 nursing homes) serving adult inpatients in Orange County, California, were included, and 42 target facilities were identified via network analyses. Exposures: Increasing contact precaution effectiveness, increasing interfacility communication about patients' MDRO status, and performing decolonization using antiseptic bathing soap and a nasal product in a specific group of target facilities. Main Outcomes and Measures: MRSA and CRE prevalence and number of new carriers (ie, transmission events). Results: Compared with continuing infection control measures used in Orange County as of 2017, increasing contact precaution effectiveness from 40% to 64% in 42 target facilities yielded relative reductions of 0.8% (range, 0.5%-1.1%) in MRSA prevalence and 2.4% (range, 0.8%-4.6%) in CRE prevalence in health care facilities countywide after 3 years, averting 761 new MRSA transmission events (95% CI, 756-765 events) and 166 new CRE transmission events (95% CI, 158-174 events). Increasing interfacility communication of patients' MDRO status to 80% in these target facilities produced no changes in the prevalence or transmission of MRDOs. Implementing decolonization procedures (clearance probability: 39% in hospitals, 27% in long-term acute care facilities, and 3% in nursing homes) yielded a relative reduction of 23.7% (range, 23.5%-23.9%) in MRSA prevalence, averting 3515 new transmission events (95% CI, 3509-3521 events). Increasing the effectiveness of antiseptic bathing soap to 48% yielded a relative reduction of 39.9% (range, 38.5%-41.5%) in CRE prevalence, averting 1435 new transmission events (95% CI, 1427-1442 events). Conclusions and Relevance: The findings of this study highlight the ways in which modeling can inform design of regional interventions and suggested that decolonization would be the best strategy for the Shared Healthcare Intervention to Eliminate Life-threatening Dissemination of MDROs in Orange County.


Asunto(s)
Infecciones Bacterianas/prevención & control , Infecciones Bacterianas/transmisión , Transmisión de Enfermedad Infecciosa/prevención & control , Farmacorresistencia Bacteriana Múltiple , Guías de Práctica Clínica como Asunto , Instituciones de Cuidados Especializados de Enfermería/normas , California , Humanos
10.
Int J Qual Health Care ; 33(3)2021 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-34282840

RESUMEN

BACKGROUND: Despite evidence that clinical outcomes for patients treated with peritoneal dialysis (PD) or home haemodialysis are better than for patients treated with conventional satellite or hospital-based haemodialysis, rates of home-based dialysis therapies world-wide remain low. Home-based dialysis care is also cost-effective and indeed the favoured dialysis option for many patients. METHODS & OBJECTIVES: Using a lean-thinking framework and established change management methodology, a project embracing a system-wide approach at making a change where a 'Home before Hospital' philosophy underpinned all approaches to dialysis care was undertaken. Three multidisciplinary working groups (pathway, outreach and hybrid) were established for re-design and implementation. The primary aim was to improve home-based dialysis therapy prevalence rates from a baseline of 14.8% by ≥2.5%/year to meet a target of 35%, whilst not only maintaining but improving the quality of care provided to patients requiring maintenance dialysis. A 'future' state pathway was developed after review of the 'current' state (Pathway Working Group) and formed the basis on which a nurse-led outreach service (Outreach Working Group) was established. With the support of the multidisciplinary team, the outreach service model focussed on early, consistent, and frequent education, patient support in decision-making, and clinician engagement. RESULTS: A target prevalence of >30% for home-based therapies (mainly achieved with PD) was achieved within 2 years. This prevalence rate reached 35% within 3 years and was maintained at 8 years. In addition, selected patients already on maintenance satellite-based haemodialysis (Hybrid Working Group) were educated to achieve high levels of proficiencies in self-care. CONCLUSION: Having the system-wide approach to a Quality Improvement Process and using established principles and change management processes, the successful implementation of a new sustainable model of care focussed on home-based dialysis therapy was achieved. A key feature of the model (through outreach) was early nurse-led education and support of patients in decision-making and ongoing support through multidisciplinary care.


Asunto(s)
Hemodiálisis en el Domicilio , Diálisis Peritoneal , Hospitales , Humanos , Mejoramiento de la Calidad , Diálisis Renal
11.
Dis Model Mech ; 14(7)2021 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-34296746

RESUMEN

Angiosarcoma (AS) is a highly aggressive tumor of blood and lymphatic vessels in humans that shares many similarities with spontaneously occurring hemangiosarcoma (HSA) in dogs and cats. To investigate the genetic suitability of HSA as a model for AS, we sequenced ∼1000 cancer genes in 41 cases of HSA and matched germline tissue: 15 canine visceral HSAs, 13 canine skin HSAs and 13 feline skin HSAs. Analysis of visceral HSAs from dogs presenting with concurrent splenic and cardiac neoplasms showed that the tumors were not independent primaries, consistent with the highly metastatic nature of HSA. Comparison of HSA to AS revealed that several driver genes were recurrently mutated in both species, such as TP53, PIK3CA, ATRX, GRIN2A and LRP1B. Similar to AS, a UV mutational signature was found in a subset of canine cutaneous HSAs and both species show differing mutational profiles between tissue sites. Our characterization of canine and feline HSA demonstrates many important parallels to AS and provides hope that future studies on these cancers will benefit of all three species.


Asunto(s)
Enfermedades de los Gatos , Enfermedades de los Perros , Hemangiosarcoma , Animales , Enfermedades de los Gatos/genética , Gatos , Enfermedades de los Perros/genética , Enfermedades de los Perros/patología , Perros , Hemangiosarcoma/genética , Hemangiosarcoma/patología , Hemangiosarcoma/veterinaria , Humanos , Mutación/genética , Oncogenes
12.
Mod Pathol ; 34(11): 2009-2019, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34155350

RESUMEN

Dedifferentiation and transdifferentiation are rare and only poorly understood phenomena in cutaneous melanoma. To study this disease more comprehensively we have retrieved 11 primary cutaneous melanomas from our pathology archives showing biphasic features characterized by a conventional melanoma and additional areas of de-/trans-differentiation as defined by a lack of immunohistochemical expression of all conventional melanocytic markers (S-100 protein, SOX10, Melan-A, and HMB-45). The clinical, histologic, and immunohistochemical findings were recorded and follow-up was obtained. The patients were mostly elderly (median: 81 years; range: 42-86 years) without significant gender predilection, and the sun-exposed skin of the head and neck area was most commonly affected. The tumors were deeply invasive with a mean depth of 7 mm (range: 4-80 mm). The dedifferentiated component showed atypical fibroxanthoma-like features in the majority of cases (7), while additional rhabdomyosarcomatous and epithelial transdifferentiation was noted histologically and/or immunohistochemically in two tumors each. The background conventional melanoma component was of desmoplastic (4), superficial spreading (3), nodular (2), lentigo maligna (1), or spindle cell (1) types. For the seven patients with available follow-up data (median follow-up period of 25 months; range: 8-36 months), two died from their disease, and three developed metastases. Next-generation sequencing of the cohort revealed somatic mutations of established melanoma drivers including mainly NF1 mutations (5) in the conventional component, which was also detected in the corresponding de-/trans-differentiated component. In summary, the diagnosis of primary cutaneous de-/trans-differentiated melanoma is challenging and depends on the morphologic identification of conventional melanoma. Molecular analysis is diagnostically helpful as the mutated gene profile is shared between the conventional and de-/trans-differentiated components. Importantly, de-/trans-differentiation does not appear to confer a more aggressive behavior.


Asunto(s)
Genómica , Melanoma/patología , Neurofibromina 1/genética , Neoplasias Cutáneas/patología , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/metabolismo , Diferenciación Celular , ADN de Neoplasias/genética , Diagnóstico Diferencial , Femenino , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Masculino , Melanoma/genética , Melanoma/metabolismo , Persona de Mediana Edad , Proteínas de Neoplasias/metabolismo , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/metabolismo
13.
Nat Commun ; 12(1): 2482, 2021 04 30.
Artículo en Inglés | MEDLINE | ID: mdl-33931647

RESUMEN

While oncogenes promote tumorigenesis, they also induce deleterious cellular stresses, such as apoptosis, that cancer cells must combat by coopting adaptive responses. Whether tumor suppressor gene haploinsufficiency leads to such phenomena and their mechanistic basis is unclear. Here, we demonstrate that elevated levels of the anti-apoptotic factor, CASP8 and FADD-like apoptosis regulator (CFLAR), promotes apoptosis evasion in acute myeloid leukemia (AML) cells haploinsufficient for the cut-like homeobox 1 (CUX1) transcription factor, whose loss is associated with dismal clinical prognosis. Genome-wide CRISPR/Cas9 screening identifies CFLAR as a selective, acquired vulnerability in CUX1-deficient AML, which can be mimicked therapeutically using inhibitor of apoptosis (IAP) antagonists in murine and human AML cells. Mechanistically, CUX1 deficiency directly alleviates CUX1 repression of the CFLAR promoter to drive CFLAR expression and leukemia survival. These data establish how haploinsufficiency of a tumor suppressor is sufficient to induce advantageous anti-apoptosis cell survival pathways and concurrently nominate CFLAR as potential therapeutic target in these poor-prognosis leukemias.


Asunto(s)
Apoptosis/genética , Proteína Reguladora de Apoptosis Similar a CASP8 y FADD/metabolismo , Regulación Neoplásica de la Expresión Génica/genética , Haploinsuficiencia , Proteínas de Homeodominio/metabolismo , Leucemia Mieloide Aguda/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Represoras/metabolismo , Animales , Apoptosis/efectos de los fármacos , Proteína Reguladora de Apoptosis Similar a CASP8 y FADD/genética , Ciclo Celular/efectos de los fármacos , Ciclo Celular/genética , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Proliferación Celular/genética , Supervivencia Celular/genética , Inmunoprecipitación de Cromatina , Dipéptidos/farmacología , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Ontología de Genes , Genes Supresores de Tumor , Células Madre Hematopoyéticas/metabolismo , Proteínas de Homeodominio/genética , Humanos , Indoles/farmacología , Estimación de Kaplan-Meier , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/mortalidad , Leucemia Mieloide Aguda/patología , Leucemia Mielomonocítica Crónica/genética , Leucemia Mielomonocítica Crónica/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Mutación , Proteínas Nucleares/deficiencia , Proteínas Nucleares/genética , Regiones Promotoras Genéticas , Análisis por Matrices de Proteínas , Proteínas Represoras/deficiencia , Proteínas Represoras/genética , Tirosina Quinasa 3 Similar a fms/genética , Tirosina Quinasa 3 Similar a fms/metabolismo
14.
Br J Cancer ; 124(1): 156-160, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33024263

RESUMEN

Brain metastases are a major cause of melanoma-related mortality and morbidity. We undertook whole-exome sequencing of 50 tumours from patients undergoing surgical resection of brain metastases presenting as the first site of visceral disease spread and validated our findings in an independent dataset of 18 patients. Brain metastases had a similar driver mutational landscape to cutaneous melanomas in TCGA. However, KRAS was the most significantly enriched driver gene, with 4/50 (8%) of brain metastases harbouring non-synonymous mutations. Hotspot KRAS mutations were mutually exclusive from BRAFV600, NRAS and HRAS mutations and were associated with a reduced overall survival from the resection of brain metastases (HR 10.01, p = 0.001). Mutations in KRAS were clonal and concordant with extracranial disease, suggesting that these mutations are likely present within the primary. Our analyses suggest that KRAS mutations could help identify patients with primary melanoma at higher risk of brain metastases who may benefit from more intensive, protracted surveillance.


Asunto(s)
Neoplasias Encefálicas/genética , Neoplasias Encefálicas/secundario , Melanoma/genética , Proteínas Proto-Oncogénicas p21(ras)/genética , Neoplasias Cutáneas/genética , Análisis Mutacional de ADN , Humanos , Mutación , Recurrencia , Melanoma Cutáneo Maligno
15.
Nat Commun ; 11(1): 4306, 2020 08 27.
Artículo en Inglés | MEDLINE | ID: mdl-32855398

RESUMEN

Metastatic melanoma carries a poor prognosis despite modern systemic therapies. Understanding the evolution of the disease could help inform patient management. Through whole-genome sequencing of 13 melanoma metastases sampled at autopsy from a treatment naïve patient and by leveraging the analytical power of multi-sample analyses, we reveal evidence of diversification among metastatic lineages. UV-induced mutations dominate the trunk, whereas APOBEC-associated mutations are found in the branches of the evolutionary tree. Multi-sample analyses from a further seven patients confirmed that lineage diversification was pervasive, representing an important mode of melanoma dissemination. Our analyses demonstrate that joint analysis of cancer cell fraction estimates across multiple metastases can uncover previously unrecognised levels of tumour heterogeneity and highlight the limitations of inferring heterogeneity from a single biopsy.


Asunto(s)
Evolución Clonal , Heterogeneidad Genética , Melanoma/genética , Neoplasias Cutáneas/genética , Anciano , Biopsia , Análisis Mutacional de ADN , Humanos , Masculino , Melanoma/secundario , Estudios Prospectivos , Piel/patología , Neoplasias Cutáneas/patología , Secuenciación Completa del Genoma
16.
Nat Commun ; 11(1): 1407, 2020 03 16.
Artículo en Inglés | MEDLINE | ID: mdl-32179751

RESUMEN

Leukaemogenic mutations commonly disrupt cellular differentiation and/or enhance proliferation, thus perturbing the regulatory programs that control self-renewal and differentiation of stem and progenitor cells. Translocations involving the Mll1 (Kmt2a) gene generate powerful oncogenic fusion proteins, predominantly affecting infant and paediatric AML and ALL patients. The early stages of leukaemogenic transformation are typically inaccessible from human patients and conventional mouse models. Here, we take advantage of cells conditionally blocked at the multipotent haematopoietic progenitor stage to develop a MLL-r model capturing early cellular and molecular consequences of MLL-ENL expression based on a clear clonal relationship between parental and leukaemic cells. Through a combination of scRNA-seq, ATAC-seq and genome-scale CRISPR-Cas9 screening, we identify pathways and genes likely to drive the early phases of leukaemogenesis. Finally, we demonstrate the broad utility of using matched parental and transformed cells for small molecule inhibitor studies by validating both previously known and other potential therapeutic targets.


Asunto(s)
Transformación Celular Neoplásica , N-Metiltransferasa de Histona-Lisina/metabolismo , Leucemia Mieloide Aguda/metabolismo , Proteína de la Leucemia Mieloide-Linfoide/metabolismo , Animales , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Modelos Animales de Enfermedad , Femenino , Células Madre Hematopoyéticas/metabolismo , N-Metiltransferasa de Histona-Lisina/genética , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/fisiopatología , Ratones , Ratones Endogámicos C57BL , Proteína de la Leucemia Mieloide-Linfoide/genética , Proteínas de Fusión Oncogénica/genética , Proteínas de Fusión Oncogénica/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
17.
EMBO J ; 39(5): e102169, 2020 03 02.
Artículo en Inglés | MEDLINE | ID: mdl-31930530

RESUMEN

Genetically engineered mouse models (GEMMs) of cancer have proven to be of great value for basic and translational research. Although CRISPR-based gene disruption offers a fast-track approach for perturbing gene function and circumvents certain limitations of standard GEMM development, it does not provide a flexible platform for recapitulating clinically relevant missense mutations in vivo. To this end, we generated knock-in mice with Cre-conditional expression of a cytidine base editor and tested their utility for precise somatic engineering of missense mutations in key cancer drivers. Upon intraductal delivery of sgRNA-encoding vectors, we could install point mutations with high efficiency in one or multiple endogenous genes in situ and assess the effect of defined allelic variants on mammary tumorigenesis. While the system also produces bystander insertions and deletions that can stochastically be selected for when targeting a tumor suppressor gene, we could effectively recapitulate oncogenic nonsense mutations. We successfully applied this system in a model of triple-negative breast cancer, providing the proof of concept for extending this flexible somatic base editing platform to other tissues and tumor types.


Asunto(s)
Neoplasias de la Mama/genética , Sistemas CRISPR-Cas , Edición Génica , Animales , Modelos Animales de Enfermedad , Femenino , Masculino , Ratones , Ratones Transgénicos , Mutación
18.
J Infect Dis ; 221(11): 1782-1794, 2020 05 11.
Artículo en Inglés | MEDLINE | ID: mdl-31150539

RESUMEN

BACKGROUND: Clinical testing detects a fraction of carbapenem-resistant Enterobacteriaceae (CRE) carriers. Detecting a greater proportion could lead to increased use of infection prevention and control measures but requires resources. Therefore, it is important to understand the impact of detecting increasing proportions of CRE carriers. METHODS: We used our Regional Healthcare Ecosystem Analyst-generated agent-based model of adult inpatient healthcare facilities in Orange County, California, to explore the impact that detecting greater proportions of carriers has on the spread of CRE. RESULTS: Detecting and placing 1 in 9 carriers on contact precautions increased the prevalence of CRE from 0% to 8.0% countywide over 10 years. Increasing the proportion of detected carriers from 1 in 9 up to 1 in 5 yielded linear reductions in transmission; at proportions >1 in 5, reductions were greater than linear. Transmission reductions did not occur for 1, 4, or 5 years, varying by facility type. With a contact precautions effectiveness of ≤70%, the detection level yielding nonlinear reductions remained unchanged; with an effectiveness of >80%, detecting only 1 in 5 carriers garnered large reductions in the number of new CRE carriers. Trends held when CRE was already present in the region. CONCLUSION: Although detection of all carriers provided the most benefits for preventing new CRE carriers, if this is not feasible, it may be worthwhile to aim for detecting >1 in 5 carriers.


Asunto(s)
Enterobacteriaceae Resistentes a los Carbapenémicos/aislamiento & purificación , Portador Sano/diagnóstico , Infecciones por Enterobacteriaceae/transmisión , Control de Infecciones/métodos , Portador Sano/epidemiología , Portador Sano/transmisión , Trazado de Contacto , Infecciones por Enterobacteriaceae/diagnóstico , Infecciones por Enterobacteriaceae/epidemiología , Infecciones por Enterobacteriaceae/prevención & control , Hospitales/estadística & datos numéricos , Humanos , Casas de Salud/estadística & datos numéricos , Prevalencia
19.
Nat Commun ; 10(1): 3163, 2019 07 18.
Artículo en Inglés | MEDLINE | ID: mdl-31320640

RESUMEN

Knowledge of key drivers and therapeutic targets in mucosal melanoma is limited due to the paucity of comprehensive mutation data on this rare tumor type. To better understand the genomic landscape of mucosal melanoma, here we describe whole genome sequencing analysis of 67 tumors and validation of driver gene mutations by exome sequencing of 45 tumors. Tumors have a low point mutation burden and high numbers of structural variants, including recurrent structural rearrangements targeting TERT, CDK4 and MDM2. Significantly mutated genes are NRAS, BRAF, NF1, KIT, SF3B1, TP53, SPRED1, ATRX, HLA-A and CHD8. SF3B1 mutations occur more commonly in female genital and anorectal melanomas and CTNNB1 mutations implicate a role for WNT signaling defects in the genesis of some mucosal melanomas. TERT aberrations and ATRX mutations are associated with alterations in telomere length. Mutation profiles of the majority of mucosal melanomas suggest potential susceptibility to CDK4/6 and/or MEK inhibitors.


Asunto(s)
Biomarcadores de Tumor/genética , Melanoma/genética , Mutación Puntual/genética , Quinasa 4 Dependiente de la Ciclina/genética , Variaciones en el Número de Copia de ADN/genética , Femenino , Humanos , Masculino , Melanocitos/patología , Melanoma/patología , Proteínas Proto-Oncogénicas c-mdm2/genética , Transducción de Señal/genética , Telomerasa/genética , Secuenciación Completa del Genoma
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...