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1.
Nucleic Acids Res ; 52(13): 7740-7760, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-38932701

RESUMO

Androgen receptor- (AR-) indifference is a mechanism of resistance to hormonal therapy in prostate cancer (PC). Here we demonstrate that ONECUT2 (OC2) activates resistance through multiple drivers associated with adenocarcinoma, stem-like and neuroendocrine (NE) variants. Direct OC2 gene targets include the glucocorticoid receptor (GR; NR3C1) and the NE splicing factor SRRM4, which are key drivers of lineage plasticity. Thus, OC2, despite its previously described NEPC driver function, can indirectly activate a portion of the AR cistrome through epigenetic activation of GR. Mechanisms by which OC2 regulates gene expression include promoter binding, enhancement of genome-wide chromatin accessibility, and super-enhancer reprogramming. Pharmacologic inhibition of OC2 suppresses lineage plasticity reprogramming induced by the AR signaling inhibitor enzalutamide. These results demonstrate that OC2 activation promotes a range of drug resistance mechanisms associated with treatment-emergent lineage variation in PC and support enhanced efforts to therapeutically target OC2 as a means of suppressing treatment-resistant disease.


Assuntos
Adenocarcinoma , Benzamidas , Resistencia a Medicamentos Antineoplásicos , Regulação Neoplásica da Expressão Gênica , Nitrilas , Neoplasias da Próstata , Receptores Androgênicos , Receptores de Glucocorticoides , Masculino , Humanos , Receptores Androgênicos/metabolismo , Receptores Androgênicos/genética , Adenocarcinoma/genética , Adenocarcinoma/patologia , Adenocarcinoma/metabolismo , Adenocarcinoma/tratamento farmacológico , Receptores de Glucocorticoides/metabolismo , Receptores de Glucocorticoides/genética , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/genética , Benzamidas/farmacologia , Linhagem Celular Tumoral , Nitrilas/farmacologia , Feniltioidantoína/farmacologia , Feniltioidantoína/análogos & derivados , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Epigênese Genética , Proteínas de Ligação a RNA/metabolismo , Proteínas de Ligação a RNA/genética , Tumores Neuroendócrinos/genética , Tumores Neuroendócrinos/patologia , Tumores Neuroendócrinos/metabolismo , Tumores Neuroendócrinos/tratamento farmacológico , Animais , Linhagem da Célula/genética , Camundongos
2.
Ann Neurol ; 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39096015

RESUMO

OBJECTIVE: To understand the etiological landscape and phenotypic differences between 2 developmental and epileptic encephalopathy (DEE) syndromes: DEE with spike-wave activation in sleep (DEE-SWAS) and epileptic encephalopathy with spike-wave activation in sleep (EE-SWAS). METHODS: All patients fulfilled International League Against Epilepsy (ILAE) DEE-SWAS or EE-SWAS criteria with a Core cohort (n = 91) drawn from our Epilepsy Genetics research program, together with 10 etiologically solved patients referred by collaborators in the Expanded cohort (n = 101). Detailed phenotyping and analysis of molecular genetic results were performed. We compared the phenotypic features of individuals with DEE-SWAS and EE-SWAS. Brain-specific gene co-expression analysis was performed for D/EE-SWAS genes. RESULTS: We identified the etiology in 42/91 (46%) patients in our Core cohort, including 29/44 (66%) with DEE-SWAS and 13/47 (28%) with EE-SWAS. A genetic etiology was identified in 31/91 (34%). D/EE-SWAS genes were highly co-expressed in brain, highlighting the importance of channelopathies and transcriptional regulators. Structural etiologies were found in 12/91 (13%) individuals. We identified 10 novel D/EE-SWAS genes with a range of functions: ATP1A2, CACNA1A, FOXP1, GRIN1, KCNMA1, KCNQ3, PPFIA3, PUF60, SETD1B, and ZBTB18, and 2 novel copy number variants, 17p11.2 duplication and 5q22 deletion. Although developmental regression patterns were similar in both syndromes, DEE-SWAS was associated with a longer duration of epilepsy and poorer intellectual outcome than EE-SWAS. INTERPRETATION: DEE-SWAS and EE-SWAS have highly heterogeneous genetic and structural etiologies. Phenotypic analysis highlights valuable clinical differences between DEE-SWAS and EE-SWAS which inform clinical care and prognostic counseling. Our etiological findings pave the way for the development of precision therapies. ANN NEUROL 2024.

3.
Lab Invest ; 104(6): 102070, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38677590

RESUMO

Immunohistochemistry (IHC) is used to guide treatment decisions in multiple cancer types. For treatment with checkpoint inhibitors, programmed death ligand 1 (PD-L1) IHC is used as a companion diagnostic. However, the scoring of PD-L1 is complicated by its expression in cancer and immune cells. Separation of cancer and noncancer regions is needed to calculate tumor proportion scores (TPS) of PD-L1, which is based on the percentage of PD-L1-positive cancer cells. Evaluation of PD-L1 expression requires highly experienced pathologists and is often challenging and time-consuming. Here, we used a multi-institutional cohort of 77 lung cancer cases stained centrally with the PD-L1 22C3 clone. We developed a 4-step pipeline for measuring TPS that includes the coregistration of hematoxylin and eosin, PD-L1, and negative control (NC) digital slides for exclusion of necrosis, segmentation of cancer regions, and quantification of PD-L1+ cells. As cancer segmentation is a challenging step for TPS generation, we trained DeepLab V3 in the Visiopharm software package to outline cancer regions in PD-L1 and NC images and evaluated the model performance by mean intersection over union (mIoU) against manual outlines. Only 14 cases were required to accomplish a mIoU of 0.82 for cancer segmentation in hematoxylin-stained NC cases. For PD-L1-stained slides, a model trained on PD-L1 tiles augmented by registered NC tiles achieved a mIoU of 0.79. In segmented cancer regions from whole slide images, the digital TPS achieved an accuracy of 75% against the manual TPS scores from the pathology report. Major reasons for algorithmic inaccuracies include the inclusion of immune cells in cancer outlines and poor nuclear segmentation of cancer cells. Our transparent and stepwise approach and performance metrics can be applied to any IHC assay to provide pathologists with important insights on when to apply and how to evaluate commercial automated IHC scoring systems.


Assuntos
Antígeno B7-H1 , Imuno-Histoquímica , Neoplasias Pulmonares , Aprendizado de Máquina , Humanos , Antígeno B7-H1/metabolismo , Antígeno B7-H1/análise , Imuno-Histoquímica/métodos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Inteligência Artificial , Biomarcadores Tumorais/metabolismo , Biomarcadores Tumorais/análise
4.
Mod Pathol ; 37(4): 100447, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38369187

RESUMO

Pathologists have, over several decades, developed criteria for diagnosing and grading prostate cancer. However, this knowledge has not, so far, been included in the design of convolutional neural networks (CNN) for prostate cancer detection and grading. Further, it is not known whether the features learned by machine-learning algorithms coincide with diagnostic features used by pathologists. We propose a framework that enforces algorithms to learn the cellular and subcellular differences between benign and cancerous prostate glands in digital slides from hematoxylin and eosin-stained tissue sections. After accurate gland segmentation and exclusion of the stroma, the central component of the pipeline, named HistoEM, utilizes a histogram embedding of features from the latent space of the CNN encoder. Each gland is represented by 128 feature-wise histograms that provide the input into a second network for benign vs cancer classification of the whole gland. Cancer glands are further processed by a U-Net structured network to separate low-grade from high-grade cancer. Our model demonstrates similar performance compared with other state-of-the-art prostate cancer grading models with gland-level resolution. To understand the features learned by HistoEM, we first rank features based on the distance between benign and cancer histograms and visualize the tissue origins of the 2 most important features. A heatmap of pixel activation by each feature is generated using Grad-CAM and overlaid on nuclear segmentation outlines. We conclude that HistoEM, similar to pathologists, uses nuclear features for the detection of prostate cancer. Altogether, this novel approach can be broadly deployed to visualize computer-learned features in histopathology images.


Assuntos
Patologistas , Neoplasias da Próstata , Masculino , Humanos , Fluxo de Trabalho , Redes Neurais de Computação , Algoritmos , Neoplasias da Próstata/patologia
5.
Scand J Public Health ; 52(2): 193-204, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36718021

RESUMO

AIMS: In many countries, people with chronic health conditions have a weaker attachment to the labour market and fewer chances of re-employment. Much of the existing literature estimates the importance of institutional factors at the level of the municipality of residence or employer accommodation at the company level individually. This study examined the two levels simultaneously to disentangle the separate effects of municipal-level and of company-level factors. METHODS: Using full population data from Denmark, we estimated cross-classified multilevel models for people newly diagnosed with chronic conditions in 2010-2013 (more than 60,000 individuals in 20,000 companies). We tracked their employment outcomes for up to 5 years after diagnosis. RESULTS: The findings suggest that, in the short term, factors at the company level explain differences in the employment levels of individuals with chronic conditions more than institutional factors at the municipal level. A combination of average wage, company-level seniority, company size, and industry seem to explain much of company-level influence. In the longer term, the importance of company-level factors seemed to decline. Company-level factors explained blue collar workers' employment rates better than those of white collar workers, which is in line with the notion that blue collar workers expend more physical effort in their work so that they may be more reliant on company accommodation than white collar workers in the case of chronic conditions. CONCLUSIONS: Company-level factors affected the employment of persons newly diagnosed with chronic health conditions in the short term (in particular among workers in blue collar jobs), while municipal-level factors did not.


Assuntos
Emprego , Ocupações , Humanos , Habitação , Doença Crônica
6.
Gut ; 72(5): 896-905, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36881441

RESUMO

OBJECTIVE: Faecal microbiota transplantation (FMT) in germ-free (GF) mice is a common approach to study the causal role of the gut microbiota in metabolic diseases. Lack of consideration of housing conditions post-FMT may contribute to study heterogeneity. We compared the impact of two housing strategies on the metabolic outcomes of GF mice colonised by gut microbiota from mice treated with a known gut modulator (cranberry proanthocyanidins (PAC)) or vehicle. DESIGN: High-fat high-sucrose diet-fed GF mice underwent FMT-PAC colonisation in sterile individual positive flow ventilated cages under rigorous housing conditions and then maintained for 8 weeks either in the gnotobiotic-axenic sector or in the specific pathogen free (SPF) sector of the same animal facility. RESULTS: Unexpectedly, 8 weeks after colonisation, we observed opposing liver phenotypes dependent on the housing environment of mice. Mice housed in the GF sector receiving the PAC gut microbiota showed a significant decrease in liver weight and hepatic triglyceride accumulation compared with control group. Conversely, exacerbated liver steatosis was observed in the FMT-PAC mice housed in the SPF sector. These phenotypic differences were associated with housing-specific profiles of colonising bacterial in the gut and of faecal metabolites. CONCLUSION: These results suggest that the housing environment in which gnotobiotic mice are maintained post-FMT strongly influences gut microbiota composition and function and can lead to distinctive phenotypes in recipient mice. Better standardisation of FMT experiments is needed to ensure reproducible and translatable results.


Assuntos
Habitação , Microbiota , Animais , Camundongos , Qualidade Habitacional , Obesidade/metabolismo , Transplante de Microbiota Fecal , Fenótipo , Dieta Hiperlipídica/efeitos adversos , Vida Livre de Germes , Camundongos Endogâmicos C57BL
7.
Biophys J ; 122(21): 4194-4206, 2023 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-37766428

RESUMO

Bladder, colon, gastric, prostate, and uterine cancers originate in organs surrounded by laminin-coated smooth muscle. In human prostate cancer, tumors that are organ confined, without extracapsular extension through muscle, have an overall cancer survival rate of up to 97% compared with 32% for metastatic disease. Our previous work modeling extracapsular extension reported the blocking of tumor invasion by mutation of a laminin-binding integrin called α6ß1. Expression of the α6AA mutant resulted in a biophysical switch from cell-ECM (extracellular matrix) to cell-cell adhesion with drug sensitivity properties and an inability to invade muscle. Here we used different admixtures of α6AA and α6WT cells to test the cell heterogeneity requirements for muscle invasion. Time-lapse video microscopy revealed that tumor mixtures self-assembled into invasive networks in vitro, whereas α6AA cells assembled only as cohesive clusters. Invasion of α6AA cells into and through live muscle occurred using a 1:1 mixture of α6AA and α6WT cells. Electric cell-substrate impedance sensing measurements revealed that compared with α6AA cells, invasion-competent α6WT cells were 2.5-fold faster at closing a cell-ECM or cell-cell wound, respectively. Cell-ECM rebuilding kinetics show that an increased response occurred in mixtures since the response was eightfold greater compared with populations containing only one cell type. A synthetic cell adhesion cyclic peptide called MTI-101 completely blocked electric cell-substrate impedance sensing cell-ECM wound recovery that persisted in vitro up to 20 h after the wound. Treatment of tumor-bearing animals with 10 mg/kg MTI-101 weekly resulted in a fourfold decrease of muscle invasion by tumor and a decrease of the depth of invasion into muscle comparable to the α6AA cells. Taken together, these data suggest that mixed biophysical phenotypes of tumor cells within a population can provide functional advantages for tumor invasion into and through muscle that can be potentially inhibited by a synthetic cell adhesion molecule.


Assuntos
Extensão Extranodal , Laminina , Masculino , Animais , Humanos , Laminina/química , Laminina/genética , Laminina/metabolismo , Integrina alfa6/genética , Integrina alfa6/metabolismo , Adesão Celular , Músculos/metabolismo , Fenótipo
8.
Mod Pathol ; 36(12): 100331, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37716506

RESUMO

Microscopic evaluation of glands in the colon is of utmost importance in the diagnosis of inflammatory bowel disease and cancer. When properly trained, deep learning pipelines can provide a systematic, reproducible, and quantitative assessment of disease-related changes in glandular tissue architecture. The training and testing of deep learning models require large amounts of manual annotations, which are difficult, time-consuming, and expensive to obtain. Here, we propose a method for automated generation of ground truth in digital hematoxylin and eosin (H&E)-stained slides using immunohistochemistry (IHC) labels. The image processing pipeline generates annotations of glands in H&E histopathology images from colon biopsy specimens by transfer of gland masks from KRT8/18, CDX2, or EPCAM IHC. The IHC gland outlines are transferred to coregistered H&E images for training of deep learning models. We compared the performance of the deep learning models to that of manual annotations using an internal held-out set of biopsy specimens as well as 2 public data sets. Our results show that EPCAM IHC provides gland outlines that closely match manual gland annotations (Dice = 0.89) and are resilient to damage by inflammation. In addition, we propose a simple data sampling technique that allows models trained on data from several sources to be adapted to a new data source using just a few newly annotated samples. The best performing models achieved average Dice scores of 0.902 and 0.89 on Gland Segmentation and Colorectal Adenocarcinoma Gland colon cancer public data sets, respectively, when trained with only 10% of annotated cases from either public cohort. Altogether, the performances of our models indicate that automated annotations using cell type-specific IHC markers can safely replace manual annotations. Automated IHC labels from single-institution cohorts can be combined with small numbers of hand-annotated cases from multi-institutional cohorts to train models that generalize well to diverse data sources.


Assuntos
Neoplasias do Colo , Aprendizado Profundo , Humanos , Molécula de Adesão da Célula Epitelial , Imuno-Histoquímica , Processamento de Imagem Assistida por Computador
9.
Acc Chem Res ; 55(23): 3362-3375, 2022 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-36343339

RESUMO

Atropisomeric compounds are found extensively as natural products, as ligands for asymmetric transition-metal catalysis, and increasingly as bioactive and pharmaceutically relevant targets. Their enantioselective synthesis is therefore an important ongoing research target. While a vast majority of known atropisomeric structures are (hetero)biaryls, which display hindered rotation around a C-C single bond, our group's long-standing interest in the control of molecular conformation has led to the identification and stereoselective preparation of a variety of other classes of "nonbiaryl" atropisomeric compounds displaying restricted rotation around C-C, C-N, C-O, and C-S single bonds.Biocatalytic transformations are finding increasing application in both academic and industrial contexts as a result of a significant broadening of the range of biocatalytic reactions and sources of enzymes available to the synthetic chemist. In this Account, we summarize the main biocatalytic strategies currently available for the asymmetric synthesis of biaryl, heterobiaryl, and nonbiaryl atropisomers. As is the case with more traditional synthetic approaches to these compounds, most biocatalytic methodologies for the construction of enantioenriched atropisomers follow one of two distinct strategies. The first of these is the direct asymmetric construction of atropisomeric bonds. Synthetically applicable biocatalytic methodologies for this type of transformation are limited, despite the extensive research into the biosynthesis of (hetero)biaryls by oxidative homocoupling or cross-coupling of electron-rich arenes. The second of these is the asymmetric transformation of a molecule in which the bond that will form the axis already exists, and this approach represents the majority of biocatalytic strategies available to the synthetic organic chemist. This strategy encompasses a variety of stereoselective techniques including kinetic resolution (KR), desymmetrization, dynamic kinetic resolution (DKR), and dynamic kinetic asymmetric transformation (DYKAT).Nondynamic kinetic resolution (KR) of conformationally stable biaryl derivatives has provided the earliest and most numerous examples of synthetically useful methodologies for the enantioselective preparation of atropisomeric compounds. Lipases (i.e., enzymes that mediate the formation or hydrolysis of esters) are particularly effective and have attracted broad attention. This success has led researchers to broaden the scope of lipase-mediated transformations to desymmetrization reactions, in addition to a limited number of DKR and DYKAT examples. By contrast, our group has used redox enzymes, including an engineered galactose oxidase (GOase) and commercially available ketoreductases (KREDs), to desymmetrize prochiral atropisomeric diaryl ether and biaryl derivatives. Building on this experience and our long-standing interest in dynamic conformational processes, we later harnessed intramolecular noncovalent interactions to facilitate bond rotation at ambient temperatures, which allowed the development of the efficient DKR of heterobiaryl aldehydes using KREDs. With this Account we provide an overview of the current and prospective biocatalytic strategies available to the synthetic organic chemist for the enantioselective preparation of atropisomeric molecules.


Assuntos
Estereoisomerismo , Estudos Prospectivos , Biocatálise , Conformação Molecular , Catálise
10.
Nutr Neurosci ; 26(7): 667-679, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35714163

RESUMO

Background: Gut microbiota has emerged as a modifiable factor influencing obesity and metabolic diseases. Interventions targeting this microbial community could attenuate biological and psychological comorbidities of excess weight. Objective: Our aim was to determine if Lacticaseibacillus rhamnosus HA-114 supplementation accentuated beneficial impact of weight loss on metabolic and cognitive health. Methods: This 12-week randomized, double-blind, placebo-controlled trial assessed biological markers of energy metabolism, eating behaviors and mood-related factors in 152 adults with overweight receiving L. rhamnosus HA-114 supplementation or placebo, that were also on a dietary intervention inducing a controlled weight loss. Results: Although probiotic supplementation did not potentiate the reduction in body weight or fat mass, a significant decrease in plasma insulin, HOMA-IR, LDL-cholesterol and triglycerides was observed in the probiotic-supplemented group only. With respect to eating behaviors and mood-related factors, beneficial effects were either observed only in the group receiving probiotic supplementation or were significantly greater in this group, including decrease in binge eating tendencies, disinhibition and food-cravings. Conclusion: This study demonstrates the clinical relevance of probiotic supplementation to induce beneficial metabolic and psychological outcomes in individuals with overweight undergoing weight loss.Trial registration: ClinicalTrials.gov identifier: NCT02962583.


Assuntos
Lacticaseibacillus rhamnosus , Probióticos , Adulto , Humanos , Sobrepeso , Lacticaseibacillus , Comportamento Alimentar , Probióticos/uso terapêutico , Método Duplo-Cego , Redução de Peso
11.
Int J Obes (Lond) ; 44(9): 1818-1831, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32523034

RESUMO

The prevalence of obesity is rising every year and associated comorbidities such as cardiovascular diseases are among the leading causes of death worldwide. The gut microbiota has recently emerged as a potential target for therapeutic applications to prevent and treat those comorbidities. In this review, we focus on three conditions related to obesity in which the use of gut microbiota modulators could have benefits; mood disorders, eating behaviors, and body detoxification of persistent organic pollutants (POPs). On one hand, modulation of gut-derived signals to the brain in a context of obesity is involved in the development of neuroinflammation and can subsequently alter behaviors. An altered gut microbiome could change these signals and alleviate their consequences. On the other hand, obesity is associated with an increased accumulation of lipophilic contaminants, such as POPs. Targeting the microbiota could help body detoxication by reducing bioavailability, enhancing degradation by bioremediation or their excretion through the enterohepatic circulation. Thus, a supplementation of prebiotics, probiotics, or synbiotics could represent a complementary strategy to current ones, such as medication and lifestyle modifications, to decrease depression, alter eating behaviors, and lower body burden of pollutants considering the actual obesity epidemic our society is facing.


Assuntos
Encéfalo/fisiologia , Microbioma Gastrointestinal/fisiologia , Obesidade , Suplementos Nutricionais , Humanos , Obesidade/microbiologia , Obesidade/fisiopatologia , Obesidade/terapia , Prebióticos , Probióticos/uso terapêutico , Simbióticos
12.
BMC Med Genet ; 21(1): 167, 2020 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-32838755

RESUMO

BACKGROUND: Mutations in the exonuclease domain of POLE, a DNA polymerase associated with DNA replication and repair, lead to cancers with ultra-high mutation rates. Most studies focus on intestinal and uterine cancers with POLE mutations. These cancers exhibit a significant immune cell infiltrate and favorable prognosis. We questioned whether loss of function of other DNA polymerases can cooperate to POLE to generate the ultramutator phenotype. METHODS: We used cases and data from 15 cancer types in The Cancer Genome Atlas to investigate mutation frequencies of 14 different DNA polymerases. We tested whether tumor mutation burden, patient outcome (disease-free survival) and immune cell infiltration measured by ESTIMATE can be attributed to mutations in POLQ and POLZ/REV3L. RESULTS: Thirty six percent of colorectal, stomach and endometrial cancers with POLE mutations carried additional mutations in POLQ (E/Q), POLZ/REV3L (E/Z) or both DNA polymerases (E/Z/Q). The mutation burden in these tumors was significantly greater compared to POLE-only (E) mutant tumors (p < 0.001). In addition, E/Q, E/Z, and E/Q/Z mutant tumors possessed an increased frequency of mutations in the POLE exonuclease domain (p = 0.013). Colorectal, stomach and endometrial E/Q, E/Z, and E/Q/Z mutant tumors within TCGA demonstrated 100% disease-free survival, even if the POLE mutations occurred outside the exonuclease domain (p = 0.003). However, immune scores in these tumors were related to microsatellite instability (MSI) and not POLE mutation status. This suggests that the host immune response may not be the sole mechanism for prolonged disease-free survival of ultramutated tumors in this cohort. CONCLUSION: Results in this study demonstrate that mutations in POLQ and REV3L in POLE mutant tumors should undergo further investigation to determine whether POLQ and REV3L mutations contribute to the ultramutator phenotype and favorable outcome of patients with POLE mutant tumors.


Assuntos
Proteínas de Ligação a DNA/genética , DNA Polimerase Dirigida por DNA/genética , Exonucleases/genética , Mutação , Neoplasias/genética , Estudos de Coortes , Exonucleases/química , Exonucleases/metabolismo , Feminino , Humanos , Sistema Imunitário/citologia , Sistema Imunitário/metabolismo , Estimativa de Kaplan-Meier , Masculino , Instabilidade de Microssatélites , Neoplasias/classificação , Neoplasias/enzimologia , Domínios Proteicos , Sequenciamento do Exoma/estatística & dados numéricos , DNA Polimerase teta
13.
BMC Cancer ; 20(1): 398, 2020 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-32380981

RESUMO

BACKGROUND: Metastatic prostate cancer (PC) is highly lethal. The ability to identify primary tumors capable of dissemination is an unmet need in the quest to understand lethal biology and improve patient outcomes. Previous studies have linked chromosomal instability (CIN), which generates aneuploidy following chromosomal missegregation during mitosis, to PC progression. Evidence of CIN includes broad copy number alterations (CNAs) spanning > 300 base pairs of DNA, which may also be measured via RNA expression signatures associated with CNA frequency. Signatures of CIN in metastatic PC, however, have not been interrogated or well defined. We examined a published 70-gene CIN signature (CIN70) in untreated and castration-resistant prostate cancer (CRPC) cohorts from The Cancer Genome Atlas (TCGA) and previously published reports. We also performed transcriptome and CNA analysis in a unique cohort of untreated primary tumors collected from diagnostic prostate needle biopsies (PNBX) of localized (M0) and metastatic (M1) cases to determine if CIN was linked to clinical stage and outcome. METHODS: PNBX were collected from 99 patients treated in the VA Greater Los Angeles (GLA-VA) Healthcare System between 2000 and 2016. Total RNA was extracted from high-grade cancer areas in PNBX cores, followed by RNA sequencing and/or copy number analysis using OncoScan. Multivariate logistic regression analyses permitted calculation of odds ratios for CIN status (high versus low) in an expanded GLA-VA PNBX cohort (n = 121). RESULTS: The CIN70 signature was significantly enriched in primary tumors and CRPC metastases from M1 PC cases. An intersection of gene signatures comprised of differentially expressed genes (DEGs) generated through comparison of M1 versus M0 PNBX and primary CRPC tumors versus metastases revealed a 157-gene "metastasis" signature that was further distilled to 7-genes (PC-CIN) regulating centrosomes, chromosomal segregation, and mitotic spindle assembly. High PC-CIN scores correlated with CRPC, PC-death and all-cause mortality in the expanded GLA-VA PNBX cohort. Interestingly, approximately 1/3 of M1 PNBX cases exhibited low CIN, illuminating differential pathways of lethal PC progression. CONCLUSIONS: Measuring CIN in PNBX by transcriptome profiling is feasible, and the PC-CIN signature may identify patients with a high risk of lethal progression at the time of diagnosis.


Assuntos
Aneuploidia , Biomarcadores Tumorais/genética , Instabilidade Cromossômica/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Idoso , Idoso de 80 Anos ou mais , Biópsia por Agulha/métodos , Bases de Dados Genéticas/estatística & dados numéricos , Progressão da Doença , Perfilação da Expressão Gênica/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Estadiamento de Neoplasias , Prognóstico , Neoplasias da Próstata/metabolismo , Análise de Sequência de RNA , Taxa de Sobrevida
14.
Nature ; 510(7503): 129-33, 2014 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-24870240

RESUMO

The development of new chemical transformations based on catalytic functionalization of unactivated C-H bonds has the potential to simplify the synthesis of complex molecules dramatically. Transition metal catalysis has emerged as a powerful tool with which to convert these unreactive bonds into carbon-carbon and carbon-heteroatom bonds, but the selective transformation of aliphatic C-H bonds is still a challenge. The most successful approaches involve a 'directing group', which positions the metal catalyst near a particular C-H bond, so that the C-H functionalization step occurs via cyclometallation. Most directed aliphatic C-H activation processes proceed through a five-membered-ring cyclometallated intermediate. Considering the number of new reactions that have arisen from such intermediates, it seems likely that identification of distinct cyclometallation pathways would lead to the development of other useful chemical transformations. Here we report a palladium-catalysed C-H bond activation mode that proceeds through a four-membered-ring cyclopalladation pathway. The chemistry described here leads to the selective transformation of a methyl group that is adjacent to an unprotected secondary amine into a synthetically versatile nitrogen heterocycle. The scope of this previously unknown bond disconnection is highlighted through the development of C-H amination and carbonylation processes, leading to the synthesis of aziridines and ß-lactams (respectively), and is suggestive of a generic C-H functionalization platform that could simplify the synthesis of aliphatic secondary amines, a class of small molecules that are particularly important features of many pharmaceutical agents.

15.
Angew Chem Int Ed Engl ; 59(50): 22403-22407, 2020 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-32866342

RESUMO

The synthetically versatile pinacol boronic ester group (Bpin) is generally thought of as a bulky moiety because of the two adjacent quaternary sp3 -hydribized carbon atoms in its diol backbone. However, recent diastereoselective reactions reported in the literature have cast doubt on this perception. Reported herein is a detailed experimental and computational analysis of Bpin and structurally related boronic esters which allows determination of three different steric parameters for the Bpin group: the A-value, ligand cone angle, and percent buried volume. All three parameters suggest that the Bpin moiety is remarkably small, with the planarity of the oxygen-boron-oxygen motif playing an important role in minimising steric interactions. Of the three steric parameters, percent buried volume provides the best correlation between steric size and diastereoselectivity in a Diels-Alder reaction.

16.
Cancer ; 125(20): 3595-3602, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31287163

RESUMO

BACKGROUND: In recent years, there has been growing awareness of the distinct characteristics of adolescents and young adults (AYA) diagnosed with cancer. Soft-tissue sarcoma (STS) accounts for approximately 1% of all cancers diagnosed in adults and 8% of cancers diagnosed in AYA. To the best of our knowledge, only a few sarcoma registers include data regarding histological subtype, age at diagnosis, and detailed clinical information. Therefore, little is known regarding clinical presentation and outcomes in AYA diagnosed with STS. METHODS: Using the Scandinavian Sarcoma Group Central Register, data were obtained regarding 4977 patients who were diagnosed with STS for the period between 1986 and 2011. AYA (those aged 18-39 years) were compared with older adults (OA; those aged 40-80 years) with respect to clinical presentation, treatment, and outcome. RESULTS: There were 868 AYA and 4109 OA. Overall and by STS subtype, there were significant differences noted between AYA and OA with regard to presentation, treatment, and survival. The distribution of STS subtypes was different between OA and AYA (eg, OA were more likely to be diagnosed with malignant fibrous histiocytoma compared with AYA [34% vs 16%; P < .001]). OA also were more likely to have tumors measuring ≥5 cm (68% vs 56%; P < .001) and a higher malignancy grade (75% vs 67%; P < .001). In the majority of STS subtypes AYA had significantly better overall survival and less disease recurrence compared with OA, but this finding was not true for those with malignant peripheral nerve sheath tumors. CONCLUSIONS: There are several differences between AYA and OA with STS with regard to presentation, treatment, and survival, and such differences must be taken into consideration when designing clinical trials. Additional work also is needed to characterize the potential biological mechanisms underlying these differences.


Assuntos
Recidiva Local de Neoplasia/epidemiologia , Sarcoma/epidemiologia , Caracteres Sexuais , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/terapia , Fatores de Risco , Sarcoma/patologia , Sarcoma/terapia , Resultado do Tratamento , Adulto Jovem
17.
J Cell Sci ; 130(1): 104-110, 2017 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-27609833

RESUMO

Basal cells in a simple secretory epithelium adhere to the extracellular matrix (ECM), providing contextual cues for ordered repopulation of the luminal cell layer. Early high-grade prostatic intraepithelial neoplasia (HG-PIN) tissue has enlarged nuclei and nucleoli, luminal layer expansion and genomic instability. Additional HG-PIN markers include loss of α6ß4 integrin or its ligand laminin-332, and budding of tumor clusters into laminin-511-rich stroma. We modeled the invasive budding phenotype by reducing expression of α6ß4 integrin in spheroids formed from two normal human stable isogenic prostate epithelial cell lines (RWPE-1 and PrEC 11220). These normal cells continuously spun in culture, forming multicellular spheroids containing an outer laminin-332 layer, basal cells (expressing α6ß4 integrin, high-molecular-weight cytokeratin and p63, also known as TP63) and luminal cells that secrete PSA (also known as KLK3). Basal cells were optimally positioned relative to the laminin-332 layer as determined by spindle orientation. ß4-integrin-defective spheroids contained a discontinuous laminin-332 layer corresponding to regions of abnormal budding. This 3D model can be readily used to study mechanisms that disrupt laminin-332 continuity, for example, defects in the essential adhesion receptor (ß4 integrin), laminin-332 or abnormal luminal expansion during HG-PIN progression.


Assuntos
Neoplasia Prostática Intraepitelial/patologia , Neoplasias da Próstata/patologia , Moléculas de Adesão Celular/metabolismo , Linhagem Celular Tumoral , Humanos , Integrina alfa6beta4/metabolismo , Masculino , Modelos Biológicos , Morfogênese , Gradação de Tumores , Invasividade Neoplásica , Fenótipo , Próstata/metabolismo , Próstata/patologia , Neoplasia Prostática Intraepitelial/metabolismo , Neoplasias da Próstata/metabolismo , Esferoides Celulares/metabolismo , Esferoides Celulares/patologia , Calinina
18.
Cancer Causes Control ; 30(2): 177-185, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30560391

RESUMO

PURPOSE: Previous studies have suggested an association between relative leukocyte telomere length (rLTL) and glioma risk. This association may be influenced by several factors, including allergies, BMI, and smoking. Previous studies have shown that individuals with asthma and allergy have shortened relative telomere length, and decreased risk of glioma. Though, the details and the interplay between rLTL, asthma and allergies, and glioma molecular phenotype is largely unknown. METHODS: rLTL was measured by qPCR in a Swedish population-based glioma case-control cohort (421 cases and 671 controls). rLTL was related to glioma risk and health parameters associated with asthma and allergy, as well as molecular events in glioma including IDH1 mutation, 1p/19q co-deletion, and EGFR amplification. RESULTS: Longer rLTL was associated with increased risk of glioma (OR = 1.16; 95% CI 1.02-1.31). Similar to previous reports, there was an inverse association between allergy and glioma risk. Specific, allergy symptoms including watery eyes was most strongly associated with glioma risk. High body mass index (BMI) a year prior diagnosis was significantly protective against glioma in our population. Adjusting for allergy, asthma, BMI, and smoking did not markedly change the association between longer rLTL and glioma risk. rLTL among cases was not associated with IDH1 mutation, 1p/19q co-deletion, or EGFR amplification, after adjusting for age at diagnosis and sex. CONCLUSIONS: In this Swedish glioma case-control cohort, we identified that long rLTL increases the risk of glioma, an association not confounded by allergy, BMI, or smoking. This highlights the complex interplay of the immune system, rLTL and cancer risk.


Assuntos
Neoplasias Encefálicas/epidemiologia , Glioma/epidemiologia , Leucócitos , Telômero , Adulto , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Neoplasias Encefálicas/genética , Estudos de Casos e Controles , Fatores de Confusão Epidemiológicos , Feminino , Glioma/genética , Humanos , Hipersensibilidade/epidemiologia , Masculino , Pessoa de Meia-Idade , Fenótipo , Fatores de Risco , Fumar/epidemiologia , Suécia/epidemiologia
19.
Eur J Clin Invest ; 49(8): e13149, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31172515

RESUMO

BACKGROUND: Circulating platelet micro-RNAs (miRNAs) may be used to monitor platelet function during dual antiplatelet therapy (DAPT). Aim of the study was to measure plasma levels of specific miRNAs (miRNA-223, -150, -21 and -126) after physician-driven cessation of chronic P2Y12 inhibition and to study differences in the expression levels of these miRNAs between the different oral P2Y12 inhibitors clopidogrel, prasugrel and ticagrelor, respectively. DESIGN: Patients with coronary artery disease (CAD) on DAPT maintenance dose (including aspirin 100 mg OD, plus clopidogrel 75 mg OD, or prasugrel 10 mg OD, or ticagrelor 90 mg BID) were prospectively enrolled before cessation of the P2Y12-inhibitor therapy. MiRNA-223, -150, -21 and -126 were determined at baseline (=last day of P2Y12-inhibitor intake) and 10, 30 and 180 days thereafter. RESULTS: Cessation of P2Y12-inhibitor therapy did not significantly change miRNA levels. However, in ticagrelor-treated patients, miRNA levels were significantly increased at baseline (miRNA-223 and -21), day 10 (miRNA-223, -150, -21, -126) and day 30 (miRNA-223, -150, -21, -126) as compared to prasugrel, and at day 10 (miRNA-150 and -21) and day 30 (miRNA-150) as compared to clopidogrel (all P < 0.05). At day 180, only miRNA-126 levels differed significantly with respect to the P2Y12 inhibitor used (P < 0.05). After adjustment for confounders, choice of P2Y12-inhibitor was the strongest predictor of miRNA levels (P < 0.001), while cessation of P2Y12-inhibitor therapy did not significantly impact miRNA levels. CONCLUSION: In patients with CAD, ticagrelor intake is associated with increased levels of platelet miRNAs as compared to clopidogrel and prasugrel. Platelet miRNAs are not useful to monitor platelet function after cessation of P2Y12 inhibitors.


Assuntos
Doença da Artéria Coronariana/tratamento farmacológico , MicroRNAs/sangue , Antagonistas do Receptor Purinérgico P2Y/uso terapêutico , Idoso , Aspirina/uso terapêutico , Plaquetas/metabolismo , Clopidogrel/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cloridrato de Prasugrel/uso terapêutico , Ticagrelor/uso terapêutico
20.
Angew Chem Int Ed Engl ; 58(5): 1366-1370, 2019 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-30520228

RESUMO

The one-pot sequential coupling of benzylamines, boronic esters, and aryl iodides has been investigated. In the presence of an N-activator, the boronate complex formed from an ortho-lithiated benzylamine and a boronic ester undergoes stereospecific 1,2-metalate rearrangement/anti-SN 2' elimination to form a dearomatized tertiary boronic ester. Treatment with an aryl iodide under palladium catalysis leads to rearomatizing γ-selective allylic Suzuki-Miyaura cross-coupling to generate 1,1-diarylalkanes. When enantioenriched α-substituted benzylamines are employed, the corresponding 1,1-diarylalkanes are formed with high stereospecificity.

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