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1.
Cell ; 161(4): 933-45, 2015 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-25957691

RESUMEN

In Rspondin-based 3D cultures, Lgr5 stem cells from multiple organs form ever-expanding epithelial organoids that retain their tissue identity. We report the establishment of tumor organoid cultures from 20 consecutive colorectal carcinoma (CRC) patients. For most, organoids were also generated from adjacent normal tissue. Organoids closely recapitulate several properties of the original tumor. The spectrum of genetic changes within the "living biobank" agrees well with previous large-scale mutational analyses of CRC. Gene expression analysis indicates that the major CRC molecular subtypes are represented. Tumor organoids are amenable to high-throughput drug screens allowing detection of gene-drug associations. As an example, a single organoid culture was exquisitely sensitive to Wnt secretion (porcupine) inhibitors and carried a mutation in the negative Wnt feedback regulator RNF43, rather than in APC. Organoid technology may fill the gap between cancer genetics and patient trials, complement cell-line- and xenograft-based drug studies, and allow personalized therapy design. PAPERCLIP.


Asunto(s)
Bancos de Muestras Biológicas , Neoplasias Colorrectales/patología , Ensayos de Selección de Medicamentos Antitumorales/métodos , Organoides , Neoplasias Colorrectales/tratamiento farmacológico , Proteínas de Unión al ADN/metabolismo , Humanos , Proteínas Oncogénicas/metabolismo , Técnicas de Cultivo de Órganos , Organoides/efectos de los fármacos , Medicina de Precisión , Ubiquitina-Proteína Ligasas
2.
Cell ; 156(6): 1298-1311, 2014 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-24630729

RESUMEN

Small cell lung carcinoma (SCLC) is a highly lethal, smoking-associated cancer with few known targetable genetic alterations. Using genome sequencing, we characterized the somatic evolution of a genetically engineered mouse model (GEMM) of SCLC initiated by loss of Trp53 and Rb1. We identified alterations in DNA copy number and complex genomic rearrangements and demonstrated a low somatic point mutation frequency in the absence of tobacco mutagens. Alterations targeting the tumor suppressor Pten occurred in the majority of murine SCLC studied, and engineered Pten deletion accelerated murine SCLC and abrogated loss of Chr19 in Trp53; Rb1; Pten compound mutant tumors. Finally, we found evidence for polyclonal and sequential metastatic spread of murine SCLC by comparative sequencing of families of related primary tumors and metastases. We propose a temporal model of SCLC tumorigenesis with implications for human SCLC therapeutics and the nature of cancer-genome evolution in GEMMs.


Asunto(s)
Carcinogénesis , Modelos Animales de Enfermedad , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Carcinoma Pulmonar de Células Pequeñas/genética , Carcinoma Pulmonar de Células Pequeñas/patología , Animales , Humanos , Neoplasias Hepáticas/secundario , Metástasis Linfática , Ratones , Fosfohidrolasa PTEN/genética , Fosfohidrolasa PTEN/metabolismo , Carcinoma Pulmonar de Células Pequeñas/secundario
3.
Nature ; 570(7762): 474-479, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31142838

RESUMEN

How the genomic features of a patient's cancer relate to individual disease kinetics remains poorly understood. Here we used the indolent growth dynamics of chronic lymphocytic leukaemia (CLL) to analyse the growth rates and corresponding genomic patterns of leukaemia cells from 107 patients with CLL, spanning decades-long disease courses. We found that CLL commonly demonstrates not only exponential expansion but also logistic growth, which is sigmoidal and reaches a certain steady-state level. Each growth pattern was associated with marked differences in genetic composition, the pace of disease progression and the extent of clonal evolution. In a subset of patients, whose serial samples underwent next-generation sequencing, we found that dynamic changes in the disease course of CLL were shaped by the genetic events that were already present in the early slow-growing stages. Finally, by analysing the growth rates of subclones compared with their parental clones, we quantified the growth advantage conferred by putative CLL drivers in vivo.


Asunto(s)
Progresión de la Enfermedad , Evolución Molecular , Leucemia Linfocítica Crónica de Células B/genética , Leucemia Linfocítica Crónica de Células B/patología , Proliferación Celular/efectos de los fármacos , Células Clonales/efectos de los fármacos , Células Clonales/patología , Estudios de Cohortes , Femenino , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Masculino , Recurrencia Local de Neoplasia/genética , Recurrencia Local de Neoplasia/patología , Recurrencia , Reproducibilidad de los Resultados
4.
Nature ; 547(7661): 55-60, 2017 07 06.
Artículo en Inglés | MEDLINE | ID: mdl-28658208

RESUMEN

Genomic analysis of tumours has led to the identification of hundreds of cancer genes on the basis of the presence of mutations in protein-coding regions. By contrast, much less is known about cancer-causing mutations in non-coding regions. Here we perform deep sequencing in 360 primary breast cancers and develop computational methods to identify significantly mutated promoters. Clear signals are found in the promoters of three genes. FOXA1, a known driver of hormone-receptor positive breast cancer, harbours a mutational hotspot in its promoter leading to overexpression through increased E2F binding. RMRP and NEAT1, two non-coding RNA genes, carry mutations that affect protein binding to their promoters and alter expression levels. Our study shows that promoter regions harbour recurrent mutations in cancer with functional consequences and that the mutations occur at similar frequencies as in coding regions. Power analyses indicate that more such regions remain to be discovered through deep sequencing of adequately sized cohorts of patients.


Asunto(s)
Neoplasias de la Mama/genética , Regulación Neoplásica de la Expresión Génica/genética , Mutación , Regiones Promotoras Genéticas/genética , Estudios de Cohortes , Factores de Transcripción E2F/metabolismo , Exoma/genética , Factor Nuclear 3-alfa del Hepatocito/genética , Factor Nuclear 3-alfa del Hepatocito/metabolismo , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Unión Proteica/genética , ARN Largo no Codificante/genética , Receptores de Estrógenos/antagonistas & inhibidores
5.
Hepatology ; 74(1): 133-147, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33570776

RESUMEN

BACKGROUND AND AIMS: Manual histological assessment is currently the accepted standard for diagnosing and monitoring disease progression in NASH, but is limited by variability in interpretation and insensitivity to change. Thus, there is a critical need for improved tools to assess liver pathology in order to risk stratify NASH patients and monitor treatment response. APPROACH AND RESULTS: Here, we describe a machine learning (ML)-based approach to liver histology assessment, which accurately characterizes disease severity and heterogeneity, and sensitively quantifies treatment response in NASH. We use samples from three randomized controlled trials to build and then validate deep convolutional neural networks to measure key histological features in NASH, including steatosis, inflammation, hepatocellular ballooning, and fibrosis. The ML-based predictions showed strong correlations with expert pathologists and were prognostic of progression to cirrhosis and liver-related clinical events. We developed a heterogeneity-sensitive metric of fibrosis response, the Deep Learning Treatment Assessment Liver Fibrosis score, which measured antifibrotic treatment effects that went undetected by manual pathological staging and was concordant with histological disease progression. CONCLUSIONS: Our ML method has shown reproducibility and sensitivity and was prognostic for disease progression, demonstrating the power of ML to advance our understanding of disease heterogeneity in NASH, risk stratify affected patients, and facilitate the development of therapies.


Asunto(s)
Aprendizaje Profundo , Procesamiento de Imagen Asistido por Computador/métodos , Cirrosis Hepática/diagnóstico , Hígado/patología , Enfermedad del Hígado Graso no Alcohólico/diagnóstico , Biopsia , Humanos , Cirrosis Hepática/patología , Enfermedad del Hígado Graso no Alcohólico/patología , Ensayos Clínicos Controlados Aleatorios como Asunto , Reproducibilidad de los Resultados , Índice de Severidad de la Enfermedad
6.
Nature ; 540(7631): 114-118, 2016 11 30.
Artículo en Inglés | MEDLINE | ID: mdl-27905446

RESUMEN

Germ-cell tumours (GCTs) are derived from germ cells and occur most frequently in the testes. GCTs are histologically heterogeneous and distinctly curable with chemotherapy. Gains of chromosome arm 12p and aneuploidy are nearly universal in GCTs, but specific somatic genomic features driving tumour initiation, chemosensitivity and progression are incompletely characterized. Here, using clinical whole-exome and transcriptome sequencing of precursor, primary (testicular and mediastinal) and chemoresistant metastatic human GCTs, we show that the primary somatic feature of GCTs is highly recurrent chromosome arm level amplifications and reciprocal deletions (reciprocal loss of heterozygosity), variations that are significantly enriched in GCTs compared to 19 other cancer types. These tumours also acquire KRAS mutations during the development from precursor to primary disease, and primary testicular GCTs (TGCTs) are uniformly wild type for TP53. In addition, by functional measurement of apoptotic signalling (BH3 profiling) of fresh tumour and adjacent tissue, we find that primary TGCTs have high mitochondrial priming that facilitates chemotherapy-induced apoptosis. Finally, by phylogenetic analysis of serial TGCTs that emerge with chemotherapy resistance, we show how TGCTs gain additional reciprocal loss of heterozygosity and that this is associated with loss of pluripotency markers (NANOG and POU5F1) in chemoresistant teratomas or transformed carcinomas. Our results demonstrate the distinct genomic features underlying the origins of this disease and associated with the chemosensitivity phenotype, as well as the rare progression to chemoresistance. These results identify the convergence of cancer genomics, mitochondrial priming and GCT evolution, and may provide insights into chemosensitivity and resistance in other cancers.


Asunto(s)
Resistencia a Antineoplásicos , Genoma Humano/genética , Neoplasias de Células Germinales y Embrionarias/tratamiento farmacológico , Neoplasias de Células Germinales y Embrionarias/genética , Apoptosis , Progresión de la Enfermedad , Evolución Molecular , Exoma/genética , Genómica , Humanos , Pérdida de Heterocigocidad , Masculino , Mitocondrias/metabolismo , Mutación , Proteína Homeótica Nanog/deficiencia , Metástasis de la Neoplasia/genética , Metástasis de la Neoplasia/patología , Neoplasias de Células Germinales y Embrionarias/metabolismo , Neoplasias de Células Germinales y Embrionarias/patología , Factor 3 de Transcripción de Unión a Octámeros/deficiencia , Filogenia , Proteínas Proto-Oncogénicas p21(ras)/genética , Teratoma/genética , Neoplasias Testiculares/tratamiento farmacológico , Neoplasias Testiculares/genética , Neoplasias Testiculares/metabolismo , Neoplasias Testiculares/patología , Transcriptoma/genética , Proteína p53 Supresora de Tumor/genética
7.
Nat Methods ; 15(7): 531-534, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29941871

RESUMEN

Comparison of sequencing data from a tumor sample with data from a matched germline control is a key step for accurate detection of somatic mutations. Detection sensitivity for somatic variants is greatly reduced when the matched normal sample is contaminated with tumor cells. To overcome this limitation, we developed deTiN, a method that estimates the tumor-in-normal (TiN) contamination level and, in cases affected by contamination, improves sensitivity by reclassifying initially discarded variants as somatic.


Asunto(s)
Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Neoplasias/diagnóstico , Neoplasias/genética , Análisis de Secuencia de ADN/métodos , Simulación por Computador , Humanos , Mutación
8.
Genet Med ; 23(5): 918-926, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33531667

RESUMEN

PURPOSE: Cohort-based germline variant characterization is the standard approach for pathogenic variant discovery in clinical and research samples. However, the impact of cohort size on the molecular diagnostic yield of joint genotyping is largely unknown. METHODS: Head-to-head comparison of the molecular diagnostic yield of joint genotyping in two cohorts of 239 cancer patients in the absence and then in the presence of 100 additional germline exomes. RESULTS: In 239 testicular cancer patients, 4 (7.4%, 95% confidence interval [CI]: 2.1-17.9) of 54 pathogenic variants in the cancer predisposition and American College of Medical Genetics and Genomics (ACMG) genes were missed by one or both computational runs of joint genotyping. Similarly, 8 (12.1%, 95% CI: 5.4-22.5) of 66 pathogenic variants in these genes were undetected by joint genotyping in another independent cohort of 239 breast cancer patients. An exome-wide analysis of putative loss-of-function (pLOF) variants in the testicular cancer cohort showed that 162 (8.2%, 95% CI: 7.1-9.6) pLOF variants were only detected in one analysis run but not the other, while 433 (22.0%, 95% CI: 20.2-23.9%) pLOF variants were filtered out by both analyses despite having sufficient sequencing coverage. CONCLUSION: Our analysis of the standard germline variant detection method highlighted a substantial impact of concurrently analyzing additional genomic data sets on the ability to detect clinically relevant germline pathogenic variants.


Asunto(s)
Neoplasias Testiculares , Predisposición Genética a la Enfermedad , Genómica , Genotipo , Células Germinativas , Humanos , Masculino , Patología Molecular
9.
Nature ; 526(7574): 525-30, 2015 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-26466571

RESUMEN

Which genetic alterations drive tumorigenesis and how they evolve over the course of disease and therapy are central questions in cancer biology. Here we identify 44 recurrently mutated genes and 11 recurrent somatic copy number variations through whole-exome sequencing of 538 chronic lymphocytic leukaemia (CLL) and matched germline DNA samples, 278 of which were collected in a prospective clinical trial. These include previously unrecognized putative cancer drivers (RPS15, IKZF3), and collectively identify RNA processing and export, MYC activity, and MAPK signalling as central pathways involved in CLL. Clonality analysis of this large data set further enabled reconstruction of temporal relationships between driver events. Direct comparison between matched pre-treatment and relapse samples from 59 patients demonstrated highly frequent clonal evolution. Thus, large sequencing data sets of clinically informative samples enable the discovery of novel genes associated with cancer, the network of relationships between the driver events, and their impact on disease relapse and clinical outcome.


Asunto(s)
Progresión de la Enfermedad , Evolución Molecular , Leucemia Linfocítica Crónica de Células B/genética , Mutación/genética , Recurrencia Local de Neoplasia/genética , Transformación Celular Neoplásica/genética , Células Clonales/metabolismo , Células Clonales/patología , Variaciones en el Número de Copia de ADN/genética , Exoma/genética , Genes myc/genética , Humanos , Factor de Transcripción Ikaros/genética , Leucemia Linfocítica Crónica de Células B/diagnóstico , Leucemia Linfocítica Crónica de Células B/patología , Leucemia Linfocítica Crónica de Células B/terapia , Sistema de Señalización de MAP Quinasas/genética , Pronóstico , Procesamiento Postranscripcional del ARN/genética , Transporte de ARN/genética , Proteínas Ribosómicas/genética , Resultado del Tratamiento
10.
JAMA ; 324(19): 1957-1969, 2020 11 17.
Artículo en Inglés | MEDLINE | ID: mdl-33201204

RESUMEN

Importance: Less than 10% of patients with cancer have detectable pathogenic germline alterations, which may be partially due to incomplete pathogenic variant detection. Objective: To evaluate if deep learning approaches identify more germline pathogenic variants in patients with cancer. Design, Setting, and Participants: A cross-sectional study of a standard germline detection method and a deep learning method in 2 convenience cohorts with prostate cancer and melanoma enrolled in the US and Europe between 2010 and 2017. The final date of clinical data collection was December 2017. Exposures: Germline variant detection using standard or deep learning methods. Main Outcomes and Measures: The primary outcomes included pathogenic variant detection performance in 118 cancer-predisposition genes estimated as sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). The secondary outcomes were pathogenic variant detection performance in 59 genes deemed actionable by the American College of Medical Genetics and Genomics (ACMG) and 5197 clinically relevant mendelian genes. True sensitivity and true specificity could not be calculated due to lack of a criterion reference standard, but were estimated as the proportion of true-positive variants and true-negative variants, respectively, identified by each method in a reference variant set that consisted of all variants judged to be valid from either approach. Results: The prostate cancer cohort included 1072 men (mean [SD] age at diagnosis, 63.7 [7.9] years; 857 [79.9%] with European ancestry) and the melanoma cohort included 1295 patients (mean [SD] age at diagnosis, 59.8 [15.6] years; 488 [37.7%] women; 1060 [81.9%] with European ancestry). The deep learning method identified more patients with pathogenic variants in cancer-predisposition genes than the standard method (prostate cancer: 198 vs 182; melanoma: 93 vs 74); sensitivity (prostate cancer: 94.7% vs 87.1% [difference, 7.6%; 95% CI, 2.2% to 13.1%]; melanoma: 74.4% vs 59.2% [difference, 15.2%; 95% CI, 3.7% to 26.7%]), specificity (prostate cancer: 64.0% vs 36.0% [difference, 28.0%; 95% CI, 1.4% to 54.6%]; melanoma: 63.4% vs 36.6% [difference, 26.8%; 95% CI, 17.6% to 35.9%]), PPV (prostate cancer: 95.7% vs 91.9% [difference, 3.8%; 95% CI, -1.0% to 8.4%]; melanoma: 54.4% vs 35.4% [difference, 19.0%; 95% CI, 9.1% to 28.9%]), and NPV (prostate cancer: 59.3% vs 25.0% [difference, 34.3%; 95% CI, 10.9% to 57.6%]; melanoma: 80.8% vs 60.5% [difference, 20.3%; 95% CI, 10.0% to 30.7%]). For the ACMG genes, the sensitivity of the 2 methods was not significantly different in the prostate cancer cohort (94.9% vs 90.6% [difference, 4.3%; 95% CI, -2.3% to 10.9%]), but the deep learning method had a higher sensitivity in the melanoma cohort (71.6% vs 53.7% [difference, 17.9%; 95% CI, 1.82% to 34.0%]). The deep learning method had higher sensitivity in the mendelian genes (prostate cancer: 99.7% vs 95.1% [difference, 4.6%; 95% CI, 3.0% to 6.3%]; melanoma: 91.7% vs 86.2% [difference, 5.5%; 95% CI, 2.2% to 8.8%]). Conclusions and Relevance: Among a convenience sample of 2 independent cohorts of patients with prostate cancer and melanoma, germline genetic testing using deep learning, compared with the current standard genetic testing method, was associated with higher sensitivity and specificity for detection of pathogenic variants. Further research is needed to understand the relevance of these findings with regard to clinical outcomes.


Asunto(s)
Análisis Mutacional de ADN/métodos , Aprendizaje Profundo , Pruebas Genéticas/métodos , Mutación de Línea Germinal , Melanoma/genética , Neoplasias de la Próstata/genética , Estudios Transversales , Femenino , Predisposición Genética a la Enfermedad , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Masculino , Persona de Mediana Edad , Redes Neurales de la Computación , Valor Predictivo de las Pruebas , Sensibilidad y Especificidad
11.
N Engl J Med ; 371(15): 1426-33, 2014 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-25295501

RESUMEN

Everolimus, an inhibitor of the mammalian target of rapamycin (mTOR), is effective in treating tumors harboring alterations in the mTOR pathway. Mechanisms of resistance to everolimus remain undefined. Resistance developed in a patient with metastatic anaplastic thyroid carcinoma after an extraordinary 18-month response. Whole-exome sequencing of pretreatment and drug-resistant tumors revealed a nonsense mutation in TSC2, a negative regulator of mTOR, suggesting a mechanism for exquisite sensitivity to everolimus. The resistant tumor also harbored a mutation in MTOR that confers resistance to allosteric mTOR inhibition. The mutation remains sensitive to mTOR kinase inhibitors.


Asunto(s)
Antineoplásicos/uso terapéutico , Resistencia a Antineoplásicos/genética , Sirolimus/análogos & derivados , Serina-Treonina Quinasas TOR/genética , Neoplasias de la Tiroides/terapia , Proteínas Supresoras de Tumor/genética , Terapia Combinada , Everolimus , Femenino , Humanos , Metástasis Linfática/patología , Persona de Mediana Edad , Mutación , Recurrencia Local de Neoplasia/diagnóstico por imagen , Recurrencia Local de Neoplasia/patología , Conformación Proteica , Radiografía , Sirolimus/uso terapéutico , Serina-Treonina Quinasas TOR/química , Carcinoma Anaplásico de Tiroides , Neoplasias de la Tiroides/diagnóstico por imagen , Neoplasias de la Tiroides/genética , Neoplasias de la Tiroides/patología , Proteína 2 del Complejo de la Esclerosis Tuberosa
12.
Blood ; 125(3): 516-24, 2015 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-25395418

RESUMEN

Juvenile myelomonocytic leukemia (JMML) is an aggressive myeloproliferative neoplasm of childhood associated with a poor prognosis. Recently, massively parallel sequencing has identified recurrent mutations in the SKI domain of SETBP1 in a variety of myeloid disorders. These lesions were detected in nearly 10% of patients with JMML and have been characterized as secondary events. We hypothesized that rare subclones with SETBP1 mutations are present at diagnosis in a large portion of patients who relapse, but are below the limits of detection for conventional deep sequencing platforms. Using droplet digital polymerase chain reaction, we identified SETBP1 mutations in 17/56 (30%) of patients who were treated in the Children's Oncology Group sponsored clinical trial, AAML0122. Five-year event-free survival in patients with SETBP1 mutations was 18% ± 9% compared with 51% ± 8% for those without mutations (P = .006).


Asunto(s)
Proteínas Portadoras/genética , Leucemia Mielomonocítica Juvenil/genética , Mutación/genética , Proteínas Nucleares/genética , Preescolar , Femenino , Estudios de Seguimiento , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Lactante , Recién Nacido , Leucemia Mielomonocítica Juvenil/patología , Masculino , Estadificación de Neoplasias , Pronóstico , Tasa de Supervivencia
13.
Proc Natl Acad Sci U S A ; 111(51): E5564-73, 2014 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-25512523

RESUMEN

Osteosarcoma is the most common primary bone tumor, yet there have been no substantial advances in treatment or survival in three decades. We examined 59 tumor/normal pairs by whole-exome, whole-genome, and RNA-sequencing. Only the TP53 gene was mutated at significant frequency across all samples. The mean nonsilent somatic mutation rate was 1.2 mutations per megabase, and there was a median of 230 somatic rearrangements per tumor. Complex chains of rearrangements and localized hypermutation were detected in almost all cases. Given the intertumor heterogeneity, the extent of genomic instability, and the difficulty in acquiring a large sample size in a rare tumor, we used several methods to identify genomic events contributing to osteosarcoma survival. Pathway analysis, a heuristic analytic algorithm, a comparative oncology approach, and an shRNA screen converged on the phosphatidylinositol 3-kinase/mammalian target of rapamycin (PI3K/mTOR) pathway as a central vulnerability for therapeutic exploitation in osteosarcoma. Osteosarcoma cell lines are responsive to pharmacologic and genetic inhibition of the PI3K/mTOR pathway both in vitro and in vivo.


Asunto(s)
Neoplasias Óseas/metabolismo , Genoma Humano , Osteosarcoma/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Serina-Treonina Quinasas TOR/metabolismo , Neoplasias Óseas/genética , Neoplasias Óseas/patología , Línea Celular Tumoral , Proliferación Celular , Heterogeneidad Genética , Mutación de Línea Germinal , Humanos , Osteosarcoma/genética , Osteosarcoma/patología , Proteína p53 Supresora de Tumor/genética
14.
Cereb Cortex ; 25(8): 2306-20, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24610117

RESUMEN

Traumatic brain injury (TBI) is a major risk factor for developing pharmaco-resistant epilepsy. Although disruptions in brain circuitry are associated with TBI, the precise mechanisms by which brain injury leads to epileptiform network activity is unknown. Using controlled cortical impact (CCI) as a model of TBI, we examined how cortical excitability and glutamatergic signaling was altered following injury. We optically mapped cortical glutamate signaling using FRET-based glutamate biosensors, while simultaneously recording cortical field potentials in acute brain slices 2-4 weeks following CCI. Cortical electrical stimulation evoked polyphasic, epileptiform field potentials and disrupted the input-output relationship in deep layers of CCI-injured cortex. High-speed glutamate biosensor imaging showed that glutamate signaling was significantly increased in the injured cortex. Elevated glutamate responses correlated with epileptiform activity, were highest directly adjacent to the injury, and spread via deep cortical layers. Immunoreactivity for markers of GABAergic interneurons were significantly decreased throughout CCI cortex. Lastly, spontaneous inhibitory postsynaptic current frequency decreased and spontaneous excitatory postsynaptic current increased after CCI injury. Our results suggest that specific cortical neuronal microcircuits may initiate and facilitate the spread of epileptiform activity following TBI. Increased glutamatergic signaling due to loss of GABAergic control may provide a mechanism by which TBI can give rise to post-traumatic epilepsy.


Asunto(s)
Lesiones Encefálicas/fisiopatología , Corteza Cerebral/fisiopatología , Neuronas GABAérgicas/fisiología , Ácido Glutámico/metabolismo , Animales , Astrocitos/patología , Astrocitos/fisiología , Lesiones Encefálicas/patología , Corteza Cerebral/patología , Modelos Animales de Enfermedad , Epilepsia/fisiopatología , Transportador 1 de Aminoácidos Excitadores/metabolismo , Transportador 2 de Aminoácidos Excitadores/metabolismo , Potenciales Postsinápticos Excitadores/fisiología , Neuronas GABAérgicas/patología , Potenciales Postsinápticos Inhibidores/fisiología , Masculino , Ratones Endogámicos C57BL , Vías Nerviosas/patología , Vías Nerviosas/fisiopatología , Parvalbúminas/metabolismo , Somatostatina/metabolismo , Técnicas de Cultivo de Tejidos
15.
Neurobiol Dis ; 71: 305-16, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25158291

RESUMEN

Developmental cortical malformations are associated with a high incidence of drug-resistant epilepsy. The underlying epileptogenic mechanisms, however, are poorly understood. In rodents, cortical malformations can be modeled using neonatal freeze-lesion (FL), which has been shown to cause in vitro cortical hyperexcitability. Here, we investigated the therapeutic potential of gabapentin, a clinically used anticonvulsant and analgesic, in preventing FL-induced in vitro and in vivo hyperexcitability. Gabapentin has been shown to disrupt the interaction of thrombospondin (TSP) with α2δ-1, an auxiliary calcium channel subunit. TSP/α2δ-1 signaling has been shown to drive the formation of excitatory synapses during cortical development and following injury. Gabapentin has been reported to have neuroprotective and anti-epileptogenic effects in other models associated with increased TSP expression and reactive astrocytosis. We found that both TSP and α2δ-1 were transiently upregulated following neonatal FL. We therefore designed a one-week GBP treatment paradigm to block TSP/α2δ-1 signaling during the period of their upregulation. GBP treatment prevented epileptiform activity following FL, as assessed by both glutamate biosensor imaging and field potential recording. GBP also attenuated FL-induced increases in mEPSC frequency at both P7 and 28. Additionally, GBP treated animals had decreased in vivo kainic acid (KA)-induced seizure activity. Taken together these results suggest gabapentin treatment immediately after FL can prevent the formation of a hyperexcitable network and may have therapeutic potential to minimize epileptogenic processes associated with developmental cortical malformations.


Asunto(s)
Aminas/uso terapéutico , Anticonvulsivantes/uso terapéutico , Ácidos Ciclohexanocarboxílicos/uso terapéutico , Epilepsia/tratamiento farmacológico , Epilepsia/etiología , Malformaciones del Desarrollo Cortical/complicaciones , Corteza Somatosensorial/lesiones , Ácido gamma-Aminobutírico/uso terapéutico , Factores de Edad , Animales , Animales Recién Nacidos , Canales de Calcio/metabolismo , Modelos Animales de Enfermedad , Estimulación Eléctrica , Potenciales Evocados/efectos de los fármacos , Agonistas de Aminoácidos Excitadores/toxicidad , Potenciales Postsinápticos Excitadores/efectos de los fármacos , Congelación/efectos adversos , Gabapentina , Proteína Ácida Fibrilar de la Glía , Ácido Glutámico/metabolismo , Técnicas In Vitro , Ácido Kaínico/toxicidad , Malformaciones del Desarrollo Cortical/etiología , Ratones , Ratones Endogámicos C57BL , Neuroimagen , Técnicas de Placa-Clamp , Corteza Somatosensorial/crecimiento & desarrollo , Trombospondinas/metabolismo
16.
NPJ Precis Oncol ; 8(1): 134, 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38898127

RESUMEN

While alterations in nucleus size, shape, and color are ubiquitous in cancer, comprehensive quantification of nuclear morphology across a whole-slide histologic image remains a challenge. Here, we describe the development of a pan-tissue, deep learning-based digital pathology pipeline for exhaustive nucleus detection, segmentation, and classification and the utility of this pipeline for nuclear morphologic biomarker discovery. Manually-collected nucleus annotations were used to train an object detection and segmentation model for identifying nuclei, which was deployed to segment nuclei in H&E-stained slides from the BRCA, LUAD, and PRAD TCGA cohorts. Interpretable features describing the shape, size, color, and texture of each nucleus were extracted from segmented nuclei and compared to measurements of genomic instability, gene expression, and prognosis. The nuclear segmentation and classification model trained herein performed comparably to previously reported models. Features extracted from the model revealed differences sufficient to distinguish between BRCA, LUAD, and PRAD. Furthermore, cancer cell nuclear area was associated with increased aneuploidy score and homologous recombination deficiency. In BRCA, increased fibroblast nuclear area was indicative of poor progression-free and overall survival and was associated with gene expression signatures related to extracellular matrix remodeling and anti-tumor immunity. Thus, we developed a powerful pan-tissue approach for nucleus segmentation and featurization, enabling the construction of predictive models and the identification of features linking nuclear morphology with clinically-relevant prognostic biomarkers across multiple cancer types.

17.
Nat Med ; 30(10): 2914-2923, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39112795

RESUMEN

Clinical trials in metabolic dysfunction-associated steatohepatitis (MASH, formerly known as nonalcoholic steatohepatitis) require histologic scoring for assessment of inclusion criteria and endpoints. However, variability in interpretation has impacted clinical trial outcomes. We developed an artificial intelligence-based measurement (AIM) tool for scoring MASH histology (AIM-MASH). AIM-MASH predictions for MASH Clinical Research Network necroinflammation grades and fibrosis stages were reproducible (κ = 1) and aligned with expert pathologist consensus scores (κ = 0.62-0.74). The AIM-MASH versus consensus agreements were comparable to average pathologists for MASH Clinical Research Network scores (82% versus 81%) and fibrosis (97% versus 96%). Continuous scores produced by AIM-MASH for key histological features of MASH correlated with mean pathologist scores and noninvasive biomarkers and strongly predicted progression-free survival in patients with stage 3 (P < 0.0001) and stage 4 (P = 0.03) fibrosis. In a retrospective analysis of the ATLAS trial (NCT03449446), responders receiving study treatment showed a greater continuous change in fibrosis compared with placebo (P = 0.02). Overall, these results suggest that AIM-MASH may assist pathologists in histologic review of MASH clinical trials, reducing inter-rater variability on trial outcomes and offering a more sensitive and reproducible measure of patient responses.


Asunto(s)
Inteligencia Artificial , Ensayos Clínicos como Asunto , Enfermedad del Hígado Graso no Alcohólico , Humanos , Enfermedad del Hígado Graso no Alcohólico/patología , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Cirrosis Hepática/patología , Selección de Paciente , Determinación de Punto Final , Femenino , Estudios Retrospectivos , Masculino , Automatización , Hepatopatías/patología , Reproducibilidad de los Resultados
18.
Cell Rep Med ; 4(4): 101016, 2023 04 18.
Artículo en Inglés | MEDLINE | ID: mdl-37075704

RESUMEN

Nonalcoholic steatohepatitis (NASH) is the most common chronic liver disease globally and a leading cause for liver transplantation in the US. Its pathogenesis remains imprecisely defined. We combined two high-resolution modalities to tissue samples from NASH clinical trials, machine learning (ML)-based quantification of histological features and transcriptomics, to identify genes that are associated with disease progression and clinical events. A histopathology-driven 5-gene expression signature predicted disease progression and clinical events in patients with NASH with F3 (pre-cirrhotic) and F4 (cirrhotic) fibrosis. Notably, the Notch signaling pathway and genes implicated in liver-related diseases were enriched in this expression signature. In a validation cohort where pharmacologic intervention improved disease histology, multiple Notch signaling components were suppressed.


Asunto(s)
Aprendizaje Profundo , Enfermedad del Hígado Graso no Alcohólico , Humanos , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Transcriptoma/genética , Progresión de la Enfermedad , Cirrosis Hepática/genética , Cirrosis Hepática/tratamiento farmacológico
19.
medRxiv ; 2023 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-37162870

RESUMEN

Clinical trials in nonalcoholic steatohepatitis (NASH) require histologic scoring for assessment of inclusion criteria and endpoints. However, guidelines for scoring key features have led to variability in interpretation, impacting clinical trial outcomes. We developed an artificial intelligence (AI)-based measurement (AIM) tool for scoring NASH histology (AIM-NASH). AIM-NASH predictions for NASH Clinical Research Network (CRN) grades of necroinflammation and stages of fibrosis aligned with expert consensus scores and were reproducible. Continuous scores produced by AIM-NASH for key histological features of NASH correlated with mean pathologist scores and with noninvasive biomarkers and strongly predicted patient outcomes. In a retrospective analysis of the ATLAS trial, previously unmet pathological endpoints were met when scored by the AIM-NASH algorithm alone. Overall, these results suggest that AIM-NASH may assist pathologists in histologic review of NASH clinical trials, reducing inter-rater variability on trial outcomes and offering a more sensitive and reproducible measure of patient therapeutic response.

20.
J Thorac Oncol ; 2023 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-38070597

RESUMEN

INTRODUCTION: Pathologic response (PathR) by histopathologic assessment of resected specimens may be an early clinical end point associated with long-term outcomes with neoadjuvant therapy. Digital pathology may improve the efficiency and precision of PathR assessment. LCMC3 (NCT02927301) evaluated neoadjuvant atezolizumab in patients with resectable NSCLC and reported a 20% major PathR rate. METHODS: We determined PathR in primary tumor resection specimens using guidelines-based visual techniques and developed a convolutional neural network model using the same criteria to digitally measure the percent viable tumor on whole-slide images. Concordance was evaluated between visual determination of percent viable tumor (n = 151) performed by one of the 47 local pathologists and three central pathologists. RESULTS: For concordance among visual determination of percent viable tumor, the interclass correlation coefficient was 0.87 (95% confidence interval [CI]: 0.84-0.90). Agreement for visually assessed 10% or less viable tumor (major PathR [MPR]) in the primary tumor was 92.1% (Fleiss kappa = 0.83). Digitally assessed percent viable tumor (n = 136) correlated with visual assessment (Pearson r = 0.73; digital/visual slope = 0.28). Digitally assessed MPR predicted visually assessed MPR with outstanding discrimination (area under receiver operating characteristic curve, 0.98) and was associated with longer disease-free survival (hazard ratio [HR] = 0.30; 95% CI: 0.09-0.97, p = 0.033) and overall survival (HR = 0.14, 95% CI: 0.02-1.06, p = 0.027) versus no MPR. Digitally assessed PathR strongly correlated with visual measurements. CONCLUSIONS: Artificial intelligence-powered digital pathology exhibits promise in assisting pathologic assessments in neoadjuvant NSCLC clinical trials. The development of artificial intelligence-powered approaches in clinical settings may aid pathologists in clinical operations, including routine PathR assessments, and subsequently support improved patient care and long-term outcomes.

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