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1.
Cell ; 187(8): 1971-1989.e16, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38521060

RESUMO

Amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD) share many clinical, pathological, and genetic features, but a detailed understanding of their associated transcriptional alterations across vulnerable cortical cell types is lacking. Here, we report a high-resolution, comparative single-cell molecular atlas of the human primary motor and dorsolateral prefrontal cortices and their transcriptional alterations in sporadic and familial ALS and FTLD. By integrating transcriptional and genetic information, we identify known and previously unidentified vulnerable populations in cortical layer 5 and show that ALS- and FTLD-implicated motor and spindle neurons possess a virtually indistinguishable molecular identity. We implicate potential disease mechanisms affecting these cell types as well as non-neuronal drivers of pathogenesis. Finally, we show that neuron loss in cortical layer 5 tracks more closely with transcriptional identity rather than cellular morphology and extends beyond previously reported vulnerable cell types.


Assuntos
Esclerose Lateral Amiotrófica , Degeneração Lobar Frontotemporal , Córtex Pré-Frontal , Animais , Humanos , Camundongos , Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/metabolismo , Esclerose Lateral Amiotrófica/patologia , Demência Frontotemporal/genética , Degeneração Lobar Frontotemporal/genética , Degeneração Lobar Frontotemporal/metabolismo , Degeneração Lobar Frontotemporal/patologia , Perfilação da Expressão Gênica , Neurônios/metabolismo , Córtex Pré-Frontal/metabolismo , Córtex Pré-Frontal/patologia , Análise da Expressão Gênica de Célula Única
2.
Nat Commun ; 14(1): 7830, 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-38081835

RESUMO

Developmental and epileptic encephalopathies (DEEs) are a group of rare childhood disorders characterized by severe epilepsy and cognitive deficits. Numerous DEE genes have been discovered thanks to advances in genomic diagnosis, yet putative molecular links between these disorders are unknown. CDKL5 deficiency disorder (CDD, DEE2), one of the most common genetic epilepsies, is caused by loss-of-function mutations in the brain-enriched kinase CDKL5. To elucidate CDKL5 function, we looked for CDKL5 substrates using a SILAC-based phosphoproteomic screen. We identified the voltage-gated Ca2+ channel Cav2.3 (encoded by CACNA1E) as a physiological target of CDKL5 in mice and humans. Recombinant channel electrophysiology and interdisciplinary characterization of Cav2.3 phosphomutant mice revealed that loss of Cav2.3 phosphorylation leads to channel gain-of-function via slower inactivation and enhanced cholinergic stimulation, resulting in increased neuronal excitability. Our results thus show that CDD is partly a channelopathy. The properties of unphosphorylated Cav2.3 closely resemble those described for CACNA1E gain-of-function mutations causing DEE69, a disorder sharing clinical features with CDD. We show that these two single-gene diseases are mechanistically related and could be ameliorated with Cav2.3 inhibitors.


Assuntos
Epilepsia , Síndromes Epilépticas , Espasmos Infantis , Animais , Criança , Humanos , Camundongos , Canais de Cálcio/genética , Epilepsia/genética , Síndromes Epilépticas/genética , Proteínas Serina-Treonina Quinases/genética , Espasmos Infantis/genética
3.
Int J Mol Sci ; 24(20)2023 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-37894922

RESUMO

Changes in epigenetic programming have been proposed as being key events in the initiation and progression of childhood cancers. HMT euchromatic histone lysine methyltransferase 2 (G9a, EHMT2), which is encoded by the G9a (Ehmt2) gene, as well as its related protein GLP, which is encoded by the GLP/Ehmt1 gene, participate in epigenetic regulation by contributing to a transcriptionally repressed chromatin state. G9a/GLP activation has been reported in several cancer types. Herein, we evaluated the role of G9a in two solid pediatric tumors: neuroblastoma (NB) and Ewing sarcoma (ES). Our results show that G9a/Ehmt2 and GLP/Ehmt1 expression is higher in tumors with poorer prognosis, including St4 International Neuroblastoma Staging System (INSS) stage, MYCN amplified NB, and metastatic ES. Importantly, higher G9a and GLP levels were associated with shorter patient overall survival (OS) in both NB and ES. Moreover, pharmacological inhibition of G9a/GLP reduced cell viability in NB and ES cells. These findings suggest that G9a and GLP are associated with more aggressive NB and ES tumors and should be further investigated as being epigenetic targets in pediatric solid cancers.


Assuntos
Neuroblastoma , Sarcoma de Ewing , Criança , Humanos , Sobrevivência Celular/genética , Epigênese Genética , Antígenos de Histocompatibilidade/genética , Antígenos de Histocompatibilidade/metabolismo , Histona Metiltransferases/metabolismo , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/metabolismo , Neuroblastoma/genética , Sarcoma de Ewing/genética
4.
Socius ; 92023.
Artigo em Inglês | MEDLINE | ID: mdl-37600324

RESUMO

Advocates for reform have highlighted violations of probation and parole conditions as a key driver of mass incarceration. As a 2019 Council of State Governments report declared, supervision violations are "filling prisons and burdening budgets." Yet few scholarly accounts estimate the precise role of technical violations in fueling prison populations during the prison boom. Using national surveys of state prison populations from 1979 to 2016, the authors document that most incarcerated persons are behind bars for new sentences. On average, just one in eight people in state prisons on any given day has been locked up for a technical violation of community supervision alone. Thus, strategies to substantially reduce prison populations must look to new criminal offenses and sentence length.

5.
Ann Oncol ; 34(11): 1025-1034, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37619846

RESUMO

BACKGROUND: The prognostic value of KRAS and BRAFV600E mutations in stage III colon cancer (CC) remains controversial and has never been clearly analyzed in patients with microsatellite instability-high (MSI-H) tumors due to sample size limitations. Data are also lacking for KRAS submutations and prognosis. PATIENTS AND METHODS: We examined clinicopathological variables and prognosis in patients with surgically resected stage III CC who participated in seven clinical trials from the ACCENT/IDEA databases. Associations between KRAS exon 2 and BRAFV600E mutations and time to recurrence (TTR), overall survival (OS), and survival after recurrence (SAR) were assessed using a Cox model. We also analyzed the prognostic value of KRAS exon 2 submutations. RESULTS: Among 8460 patients, 11.4% had MSI-H status. In the MSI-H group, BRAFV600E, KRAS exon 2 mutants, and double-wild-type statuses were detected in 40.6%, 18.1%, and 41.3%, respectively, whereas and in the microsatellite stable (MSS) group, these were detected in 7.7%, 38.6%, and 53.8%, respectively. In the MSS group, 5-year TTR rates of 61.8%, 66.3%, and 72.9% were observed among patients with BRAFV600E, KRAS exon 2 mutants, and those who were DWT, respectively [adjusted hazard ratio (HR) = 1.58 and 1.31, both P < 0.001]. In the MSI-H group, 5-year TTR rates did not differ significantly among the mutated subgroups. Similar results were found for OS. However, survival after relapse was significantly shorter in the KRAS exon 2- and BRAFV600E-mutated patients in both MSS (adjusted HR = 2.06 and 1.15; both P < 0.05) and MSI-H (adjusted HR = 1.99 and 1.81; both P < 0.05) groups. In the MSS group, KRAS exon 2 mutations were associated with TTR, but only p.G12C, p.G12D, and p.G13D were associated with poor outcomes after disease recurrence. CONCLUSIONS: Testing for both KRAS and BRAFV600E mutations in stage III patients should be considered as they can better define individual patient prognosis, and may also enable patient selection for (neo)adjuvant trials dedicated to specific molecular subtypes with poor prognosis.


Assuntos
Neoplasias do Colo , Instabilidade de Microssatélites , Proteínas Proto-Oncogênicas B-raf , Proteínas Proto-Oncogênicas p21(ras) , Prognóstico , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/genética , Ensaios Clínicos Controlados Aleatórios como Assunto , Humanos , Proteínas Proto-Oncogênicas p21(ras)/genética , Éxons , Proteínas Proto-Oncogênicas B-raf/genética , Masculino , Feminino , Pessoa de Meia-Idade , Resultado do Tratamento
6.
Expert Opin Ther Pat ; 33(6): 397-420, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37494069

RESUMO

INTRODUCTION: PROteolysis-TArgeting Chimeras (PROTACs) allow the selective degradation of a protein of interest (POI) by the ubiquitin-proteasome system (UPS). With this unique mechanism of action, the research and development of PROTACs that target the Breakpoint Cluster Region Abelson (BCR-ABL) tyrosine kinase (TK) has been increasing dramatically, as they are promising molecules in the treatment of Chronic Myeloid Leukemia (CML), one of the main hematological malignancies, which results from an uncontrolled myeloproliferation due to the constitutive activation of BCR-ABL. AREAS COVERED: This review summarizes the patents/applications published in the online databases like Espacenet or World Intellectual Property Organization regarding PROTACs that promote BCR-ABL degradation. Patents will be described mostly in terms of chemical structure, biochemical/pharmacological activities, and potential clinical applications. EXPERT OPINION: The recent discovery of the enormous potential of PROTACs led to the creation of new compounds capable of degrading BCR-ABL for the treatment of CML. Although still in reduced numbers, and in the pre-clinical phase of development, some compounds have already been shown to overcome some of the difficulties presented by conventional BCR-ABL inhibitors, such as the well-known imatinib. Therefore, it is very likely that some of the present PROTACs will enter future CML therapy in the coming years.


Assuntos
Antineoplásicos , Leucemia Mielogênica Crônica BCR-ABL Positiva , Humanos , Quimera de Direcionamento de Proteólise , Proteólise , Resistencia a Medicamentos Antineoplásicos , Patentes como Assunto , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Proteínas de Fusão bcr-abl/química , Proteínas de Fusão bcr-abl/metabolismo , Inibidores de Proteínas Quinases/química , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico
7.
Sensors (Basel) ; 23(10)2023 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-37430841

RESUMO

Microfluidic-based platforms have become a hallmark for chemical and biological assays, empowering micro- and nano-reaction vessels. The fusion of microfluidic technologies (digital microfluidics, continuous-flow microfluidics, and droplet microfluidics, just to name a few) presents great potential for overcoming the inherent limitations of each approach, while also elevating their respective strengths. This work exploits the combination of digital microfluidics (DMF) and droplet microfluidics (DrMF) on a single substrate, where DMF enables droplet mixing and further acts as a controlled liquid supplier for a high-throughput nano-liter droplet generator. Droplet generation is performed at a flow-focusing region, operating on dual pressure: negative pressure applied to the aqueous phase and positive pressure applied to the oil phase. We evaluate the droplets produced with our hybrid DMF-DrMF devices in terms of droplet volume, speed, and production frequency and further compare them with standalone DrMF devices. Both types of devices enable customizable droplet production (various volumes and circulation speeds), yet hybrid DMF-DrMF devices yield more controlled droplet production while achieving throughputs that are similar to standalone DrMF devices. These hybrid devices enable the production of up to four droplets per second, which reach a maximum circulation speed close to 1540 µm/s and volumes as low as 0.5 nL.


Assuntos
Microfluídica , Ácidos Nucleicos , Bioensaio , Dispositivos Lab-On-A-Chip , Tecnologia
8.
Ann Oncol ; 34(8): 703-713, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37269904

RESUMO

BACKGROUND: Mismatch repair-deficient (dMMR) tumors displaying microsatellite instability (MSI) represent a paradigm for the success of immune checkpoint inhibitor (ICI)-based immunotherapy, particularly in patients with metastatic colorectal cancer (mCRC). However, a proportion of patients with dMMR/MSI mCRC exhibit resistance to ICI. Identification of tools predicting MSI mCRC patient response to ICI is required for the design of future strategies further improving this therapy. PATIENTS AND METHODS: We combined high-throughput DNA and RNA sequencing of tumors from 116 patients with MSI mCRC treated with anti-programmed cell death protein 1 ± anti-cytotoxic T-lymphocyte-associated protein 4 of the NIPICOL phase II trial (C1, NCT03350126, discovery set) and the ImmunoMSI prospective cohort (C2, validation set). The DNA/RNA predictors whose status was significantly associated with ICI status of response in C1 were subsequently validated in C2. Primary endpoint was progression-free survival by immune RECIST (iRECIST) (iPFS). RESULTS: Analyses showed no impact of previously suggested DNA/RNA indicators of resistance to ICI, e.g. MSIsensor score, tumor mutational burden, or specific cellular and molecular tumoral contingents. By contrast, iPFS under ICI was shown in C1 and C2 to depend both on a multiplex MSI signature involving the mutations of 19 microsatellites hazard ratio cohort C2 (HRC2) = 3.63; 95% confidence interval (CI) 1.65-7.99; P = 1.4 × 10-3] and the expression of a set of 182 RNA markers with a non-epithelial transforming growth factor beta (TGFB)-related desmoplastic orientation (HRC2 = 1.75; 95% CI 1.03-2.98; P = 0.035). Both DNA and RNA signatures were independently predictive of iPFS. CONCLUSIONS: iPFS in patients with MSI mCRC can be predicted by simply analyzing the mutational status of DNA microsatellite-containing genes in epithelial tumor cells together with non-epithelial TGFB-related desmoplastic RNA markers.


Assuntos
Neoplasias do Colo , Neoplasias Colorretais , Neoplasias Retais , Humanos , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Instabilidade de Microssatélites , Estudos Prospectivos , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Reparo de Erro de Pareamento de DNA/genética
9.
JCO Glob Oncol ; 9: e2200416, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37348031

RESUMO

The incidence of hepatocellular carcinoma (HCC) is expected to increase in the coming years, and strategies to mitigate the burden of this disease are needed in different regions. Geographic variations in epidemiology and risk factors, such as viral hepatitis and metabolic disease, pose challenges in adopting programs for early detection programs and management of patients with HCC. Brazil, like other countries, has high economic and social inequality, with heterogeneous access to health care. Viral hepatitis is the main risk factor but there is growing awareness of fatty liver disease. Risk factor monitoring and screening programs are unmet priorities because patients are often diagnosed at later stages. Advances in the management of patients with HCC have been made in recent years, including new tools for selecting patients for liver transplantation, sophisticated surgical techniques, and new systemic agents. High-volume academic centers often achieve favorable results through the adoption and application of established treatments, but this is not a reality in most regions of Brazil, because of disparities in wealth and resources. As HCC management requires a coordinated and multidisciplinary team, the role of local referral centers in decentralizing access to treatments and promoting health education in different regions should be encouraged and supported.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/epidemiologia , Carcinoma Hepatocelular/terapia , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/terapia , Brasil/epidemiologia , Fatores de Risco , Incidência
10.
Lab Chip ; 23(14): 3238-3244, 2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37341773

RESUMO

Droplet-based microfluidic technology is a powerful tool for generating large numbers of monodispersed nanoliter-sized droplets for ultra-high throughput screening of molecules or single cells. Yet further progress in the development of methods for the real-time detection and measurement of passing droplets is needed for achieving fully automated systems and ultimately scalability. Existing droplet monitoring technologies are either difficult to implement by non-experts or require complex experimentation setups. Moreover, commercially available monitoring equipment is expensive and therefore limited to a few laboratories worldwide. In this work, we validated for the first time an easy-to-use, open-source Bonsai visual programming language to accurately measure in real-time droplets generated in a microfluidic device. With this method, droplets are found and characterized from bright-field images with high processing speed. We used off-the-shelf components to achieve an optical system that allows sensitive image-based, label-free, and cost-effective monitoring. As a test of its use we present the results, in terms of droplet radius, circulation speed and production frequency, of our method and compared its performance with that of the widely-used ImageJ software. Moreover, we show that similar results are obtained regardless of the degree of expertise. Finally, our goal is to provide a robust, simple to integrate, and user-friendly tool for monitoring droplets, capable of helping researchers to get started in the laboratory immediately, even without programming experience, enabling analysis and reporting of droplet data in real-time and closed-loop experiments.

11.
J Adolesc Health ; 73(4): 796, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37227339
12.
Dis Esophagus ; 36(10)2023 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-37039273

RESUMO

Self-expanding metallic stents (SEMS) are considered the treatment of choice for the palliation of dysphagia and fistulas in inoperable esophageal neoplasms. However, the safety of SEMSs in patients who received or who will be submitted to radiotherapy (RT) is uncertain. The study aimed to evaluate the impact of RT on adverse events (AEs) in patients with esophageal cancer with SEMSs. This is a retrospective study conducted at a tertiary cancer hospital from 2009 to 2018. We collected information regarding RT, the histological type of the tumor, the model of SEMSs and AEs after stent placement. Three hundred twenty-three patients with malignant stenosis or fistula were treated with SEMSs. The predominant histological type was squamous cell carcinoma (79.6%). A total of 282 partially covered and 41 fully covered SEMSs were inserted. Of the 323 patients, 182 did not received RT, 118 received RT before SEMS placement and 23 after. Comparing the group that received RT before stent insertion with the group that did not, the first one presented a higher frequency of severe pain (9/118 7.6% vs. 3/182 1.6%; P = 0.02). The group treated with RT after stent placement had a higher risk of global AEs (13/23 56.5% vs. 63/182 34.6%; P = 0.019), ingrowth/overgrowth (6/23 26.1% vs. 21/182 11.5%; P = 0.045) and gastroesophageal reflux (2/23 8.7% vs. 2/182 1.1%; P = 0.034). Treatment with RT before stent placement in patients with inoperable esophageal neoplasm prolongs survival and is associated with an increased risk of severe chest pain. Treatment with RT of patients with an esophageal stent increases the frequency of minor, not life-threatening AEs.


Assuntos
Transtornos de Deglutição , Neoplasias Esofágicas , Estenose Esofágica , Stents Metálicos Autoexpansíveis , Humanos , Estudos Retrospectivos , Resultado do Tratamento , Stents/efeitos adversos , Neoplasias Esofágicas/terapia , Neoplasias Esofágicas/complicações , Transtornos de Deglutição/etiologia , Transtornos de Deglutição/terapia , Cuidados Paliativos , Stents Metálicos Autoexpansíveis/efeitos adversos , Estenose Esofágica/terapia
13.
ESMO Open ; 8(2): 101199, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37018874

RESUMO

BACKGROUND: Fluoropyrimidines (FPs) are an essential part of the majority of systemic regimens in the treatment of metastatic colorectal cancer (CRC). The use of the oral FP S-1 has been approved by the European Medicines Agency as monotherapy or in combination with oxaliplatin or irinotecan, with or without bevacizumab, for the treatment of patients with metastatic CRC in whom it is not possible to continue treatment with another FP due to hand-foot syndrome (HFS) or cardiovascular toxicity (CVT). Subsequently, this indication has been included in the 2022 ESMO guidelines for metastatic CRC. Recommendations for use in daily practice are not available. PATIENTS AND METHODS: Based on peer-reviewed published data on the use of S-1 in Western patients with metastatic CRC who switched from infusional 5-fluorouracil (5-FU) or capecitabine to S-1 for reasons of HFS or CVT, recommendations for its use were formulated by an international group of medical oncologists with expertise in the treatment of metastatic CRC and a cardio-oncologist. RESULTS: In patients who experience pain and/or functional impairment due to HFS during treatment with capecitabine or infusional 5-FU, a switch to S-1 is recommended without prior dose reduction of capecitabine/5-FU. S-1 should preferably be initiated at full dose when HFS has decreased to grade ≤1. In patients with cardiac complaints, in whom an association with capecitabine or infusional 5-FU treatment cannot be excluded, capecitabine/5-FU should be discontinued and a switch to S-1 is recommended. CONCLUSIONS: These recommendations should guide clinicians in daily practice in the treatment of patients with metastatic CRC with FP-containing regimens.


Assuntos
Neoplasias do Colo , Neoplasias Colorretais , Síndrome Mão-Pé , Humanos , Capecitabina/efeitos adversos , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Síndrome Mão-Pé/etiologia , Síndrome Mão-Pé/tratamento farmacológico , Fluoruracila/efeitos adversos , Irinotecano/uso terapêutico , Neoplasias do Colo/tratamento farmacológico , Fatores Imunológicos/uso terapêutico
14.
J Adolesc Health ; 2023 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-36870899
15.
Exp Brain Res ; 241(4): 1173-1183, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36912948

RESUMO

Impairments in several domains of cognitive functions are observed in people with Type 2 Diabetes Mellitus (T2DM), often accompanied by low Brain-derived neurotrophic factor (BDNF) concentrations. Although aerobic and resistance exercise enhances cognitive functions and raises BDNF concentrations in several populations, it remained uncertain in T2DM subjects. This study compared the effects of a single bout of aerobic (AER, 40 min of treadmill walk at 90-95% of the maximum walk speed) or resistance (RES, 3 × 10 repetitions in eight exercises at 70% of 10-RM) exercise on specific cognitive domain performance and plasma BDNF concentrations of physically active T2DM subjects. Eleven T2DM subjects (9 women/2 men; 63 ± 7 years) performed two counterbalanced trials on non-consecutive days. Stroop Color and Word (SCW) task [assessing the attention (congruent condition) and inhibitory control (incongruent condition)], Visual response time (assessing the response time), and blood collection (for plasma BDNF concentrations) were performed pre and post-exercise sessions. With distinct magnitude, both AER and RES improved the incongruent-SCW (d = - 0.26 vs. - 0.43 in AER and RES, respectively; p < 0.05), RT(best) (d = - 0.31 vs. - 0.52, p < 0.05), and RT(1-5) (d = - 0.64 vs. - 0.21, p < 0.05). The congruent-SCW and RT(6-10) were not statistically different. Plasma BDNF concentrations were elevated 11% in AER (d = 0.30) but decreased by 15% in RES (d = - 0.43). A single session of aerobic or resistance exercise similarly improved the inhibitory control and response time of physically active T2DM subjects. Nevertheless, aerobic and resistance exercise sessions induced an opposite clinical effect in plasma BDNF concentrations.


Assuntos
Diabetes Mellitus Tipo 2 , Treinamento Resistido , Masculino , Pessoa de Meia-Idade , Humanos , Feminino , Idoso , Diabetes Mellitus Tipo 2/terapia , Fator Neurotrófico Derivado do Encéfalo , Tempo de Reação , Exercício Físico/fisiologia
16.
Nat Commun ; 14(1): 1502, 2023 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-36932076

RESUMO

Neutrophilic inflammation is a hallmark of many monogenic autoinflammatory diseases; pathomechanisms that regulate extravasation of damaging immune cells into surrounding tissues are poorly understood. Here we identified three unrelated boys with perinatal-onset of neutrophilic cutaneous small vessel vasculitis and systemic inflammation. Two patients developed liver fibrosis in their first year of life. Next-generation sequencing identified two de novo truncating variants in the Src-family tyrosine kinase, LYN, p.Y508*, p.Q507* and a de novo missense variant, p.Y508F, that result in constitutive activation of Lyn kinase. Functional studies revealed increased expression of ICAM-1 on induced patient-derived endothelial cells (iECs) and of ß2-integrins on patient neutrophils that increase neutrophil adhesion and vascular transendothelial migration (TEM). Treatment with TNF inhibition improved systemic inflammation; and liver fibrosis resolved on treatment with the Src kinase inhibitor dasatinib. Our findings reveal a critical role for Lyn kinase in modulating inflammatory signals, regulating microvascular permeability and neutrophil recruitment, and in promoting hepatic fibrosis.


Assuntos
Células Endoteliais , Vasculite , Quinases da Família src , Humanos , Dasatinibe , Células Endoteliais/metabolismo , Inflamação/metabolismo , Neutrófilos/metabolismo , Fosforilação , Quinases da Família src/genética , Quinases da Família src/metabolismo , Vasculite/genética
17.
Front Chem ; 11: 1066280, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36846854

RESUMO

Cancer is a leading cause of mortality responsible for an estimated 10 million deaths worldwide in 2020, and its incidence has been rapidly growing over the last decades. Population growth and aging, as well as high systemic toxicity and chemoresistance associated with conventional anticancer therapies reflect these high levels of incidence and mortality. Thus, efforts have been made to search for novel anticancer drugs with fewer side effects and greater therapeutic effectiveness. Nature continues to be the main source of biologically active lead compounds, and diterpenoids are considered one of the most important families since many have been reported to possess anticancer properties. Oridonin is an ent-kaurane tetracyclic diterpenoid isolated from Rabdosia rubescens and has been a target of extensive research over the last few years. It displays a broad range of biological effects including neuroprotective, anti-inflammatory, and anticancer activity against a variety of tumor cells. Several structural modifications on the oridonin and biological evaluation of its derivatives have been performed, creating a library of compounds with improved pharmacological activities. This mini-review aims to highlight the recent advances in oridonin derivatives as potential anticancer drugs, while succinctly exploring their proposed mechanisms of action. To wind up, future research perspectives in this field are also disclosed.

18.
Curr Stem Cell Res Ther ; 18(7): 926-936, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35761483

RESUMO

Resistance to chemotherapy poses a major challenge for cancer treatment. Reactivating a stem cell program resembling that seen in embryonic development can lead cancer cells to acquire a stem-cell phenotype characterized by expression of stemness genes, pluripotency, high self-renewal ability, and tumor-initiating capability. These cancer stem cells (CSCs) are usually resistant to anticancer drugs and are likely involved in treatment failure in many cancer types. Ewing sarcoma (ES) is a pediatric cancer type typically resulting from a typical genetic alteration affecting bone or soft tissues. Despite advances in treatment, survival prognostic remains poor for patients with refractory or recurrent disease. Here, we review the increasing evidence indicating that ES tumors contain a CSC subpopulation expressing stem cell genes, including BM1, OCT3/4, NANOG, and SOX2, that plays a role in resistance to drug treatment, and current experimental strategies that successfully counteract chemoresistance mediated by CSCs in ES.


Assuntos
Antineoplásicos , Sarcoma de Ewing , Humanos , Sarcoma de Ewing/tratamento farmacológico , Sarcoma de Ewing/genética , Sarcoma de Ewing/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética , Linhagem Celular Tumoral , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Células-Tronco Neoplásicas/metabolismo
19.
J Biol Chem ; 299(1): 102784, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36502921

RESUMO

Deinococcus radiodurans is known for its remarkable ability to withstand harsh stressful conditions. The outermost layer of its cell envelope is a proteinaceous coat, the S-layer, essential for resistance to and interactions with the environment. The S-layer Deinoxanthin-binding complex (SDBC), one of the main units of the characteristic multilayered cell envelope of this bacterium, protects against environmental stressors and allows exchanges with the environment. So far, specific regions of this complex, the collar and the stalk, remained unassigned. Here, these regions are resolved by cryo-EM and locally refined. The resulting 3D map shows that the collar region of this multiprotein complex is a trimer of the protein DR_0644, a Cu-only superoxide dismutase (SOD) identified here to be efficient in quenching reactive oxygen species. The same data also showed that the stalk region consists of a coiled coil that extends into the cell envelope for ∼280 Å, reaching the inner membrane. Finally, the orientation and localization of the complex are defined by in situ cryo-electron crystallography. The structural organization of the SDBC couples fundamental UV antenna properties with the presence of a Cu-only SOD, showing here coexisting photoprotective and chemoprotective functions. These features suggests how the SDBC and similar protein complexes, might have played a primary role as evolutive templates for the origin of photoautotrophic processes by combining primary protective needs with more independent energetic strategies.


Assuntos
Deinococcus , Proteínas de Bactérias/metabolismo , Membrana Celular/metabolismo , Deinococcus/química , Deinococcus/citologia , Deinococcus/metabolismo , Estresse Oxidativo , Superóxido Dismutase/metabolismo
20.
Neuromolecular Med ; 25(1): 64-74, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-35716340

RESUMO

Medulloblastoma (MB) is a malignant brain tumor that afflicts mostly children and adolescents and presents four distinct molecular subgroups, known as WNT, SHH, Group 3, and Group 4. ZEB1 is a transcription factor that promotes the expression of mesenchymal markers while restraining expression of epithelial and polarity genes. Because of ZEB1 involvement in cerebellum development, here we investigated the role of ZEB1 in MB. We found increased expression of ZEB1 in MB tumor samples compared to normal cerebellar tissue. Expression was higher in the SHH subgroup when compared to all other MB molecular subgroups. High ZEB1 expression was associated with poor prognosis in Group 3 and Group 4, whereas in patients with WNT tumors poorer prognosis were related to lower ZEB1 expression. There was a moderate correlation between ZEB1 and MYC expression in Group 3 and Group 4 MB. Treatment with the immunomodulator and histone deacetylase (HDAC) inhibitor fingolimod (FTY720) reduced ZEB1 expression specifically in D283 cells, which are representative of Group 3 and Group 4 MB. These findings reveal novel subgroup-specific associations of ZEB1 expression with survival in patients with MB and suggest that ZEB1 expression can be reduced by pharmacological agents that target HDAC activity.


Assuntos
Neoplasias Encefálicas , Neoplasias Cerebelares , Meduloblastoma , Criança , Adolescente , Humanos , Meduloblastoma/tratamento farmacológico , Meduloblastoma/genética , Cerebelo , Inibidores de Histona Desacetilases/uso terapêutico , Cloridrato de Fingolimode/uso terapêutico , Neoplasias Cerebelares/tratamento farmacológico , Neoplasias Cerebelares/genética , Homeobox 1 de Ligação a E-box em Dedo de Zinco/genética , Homeobox 1 de Ligação a E-box em Dedo de Zinco/metabolismo
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