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1.
Semin Cell Dev Biol ; 155(Pt C): 30-49, 2024 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-37380595

RESUMO

High-resolution omics, particularly single-cell and spatial transcriptomic profiling, are rapidly enhancing our comprehension of the normal molecular diversity of gliovascular cells, as well as their age-related changes that contribute to neurodegeneration. With more omic profiling studies being conducted, it is becoming increasingly essential to synthesise valuable information from the rapidly accumulating findings. In this review, we present an overview of the molecular features of neurovascular and glial cells that have been recently discovered through omic profiling, with a focus on those that have potentially significant functional implications and/or show cross-species differences between human and mouse, and that are linked to vascular deficits and inflammatory pathways in ageing and neurodegenerative disorders. Additionally, we highlight the translational applications of omic profiling, and discuss omic-based strategies to accelerate biomarker discovery and facilitate disease course-modifying therapeutics development for neurodegenerative conditions.


Assuntos
Envelhecimento , Doenças Neurodegenerativas , Humanos , Camundongos , Animais , Envelhecimento/genética , Doenças Neurodegenerativas/metabolismo , Perfilação da Expressão Gênica , Neuroglia/metabolismo , Proteômica
3.
Heart ; 110(11): 792-799, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38388470

RESUMO

OBJECTIVE: The objective is to evaluate the 5-year follow-up results of percutaneous intramyocardial septal radiofrequency ablation (PIMSRA) for hypertrophic obstructive cardiomyopathy (HOCM), including clinical status, electrocardiographic and echocardiographic characteristics. METHODS: 27 patients (age: 44.3±15.5 years; 67% men, 33% women) with severely symptomatic HOCM who underwent PIMSRA from October 2016 to September 2017 were included. Their clinical status, resting and exercise stress echocardiography, electrocardiography and cardiac MRI (CMRI) after long-term follow-up were assessed. RESULTS: One patient died of intracerebral haemorrhage 1 year post procedurally. The New York Heart Association class, Canadian Cardiovascular Society class and exercise-induced syncopal attacks improved significantly in 26 patients (all p<0.01). Left ventricular (LV) outflow tract gradients revealed sustained reduction (resting: from 95.0 to 9.0 mm Hg, p<0.001; post exercise: from 130.5 to 21.0 mm Hg, p<0.001). The echocardiographic evaluation revealed decreased septal thickness, LV posterior wall thickness and left atrial (LA) diameter (all p<0.001). CMRI data revealed decrease in LV mass index and LA volume index and increase in LV end-diastolic volume index and stroke volume index between baseline and long-term follow-up (all p<0.05). The global longitudinal strain of LV improved from (-11.9%±3.7%) before the procedure to (-13.1%±3.9%) at the last check (p<0.001). Malignant ventricular arrhythmia and heart failure events were not observed. CONCLUSIONS: PIMSRA can effectively alleviate symptoms in patients with HOCM and improve their hemodynamics in the long term. TRIAL REGISTRATION NUMBER: NCT02888132.


Assuntos
Cardiomiopatia Hipertrófica , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cardiomiopatia Hipertrófica/fisiopatologia , Cardiomiopatia Hipertrófica/cirurgia , Cardiomiopatia Hipertrófica/diagnóstico por imagem , Ablação por Cateter/métodos , Eletrocardiografia , Seguimentos , Septos Cardíacos/cirurgia , Septos Cardíacos/diagnóstico por imagem , Imagem Cinética por Ressonância Magnética/métodos , Ablação por Radiofrequência/métodos , Fatores de Tempo , Resultado do Tratamento , Função Ventricular Esquerda/fisiologia
4.
JACC CardioOncol ; 6(4): 560-571, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39239332

RESUMO

Background: Patients with cardiac tumors may present challenges for surgical resection due to poor clinical condition. Echocardiography-guided transapical radiofrequency ablation for cardiac tumors (TARFACT) potentially offers a less invasive palliative therapy option. Objectives: This study aimed to evaluate the safety and efficacy of TARFACT. Methods: Five patients with cardiac tumors (mucinous liposarcoma, myocardial hypertrophy with inflammatory cell infiltration mass, fibrous tissue tumor hyperplasia, myocardial clear cell sarcoma, and cardiac rhabdomyoma) were included. All patients underwent TARFACT and were assessed with electrocardiogram, echocardiographic imaging, biochemical analysis, and pathological confirmation. Results: The median follow-up for all patients was 9 (range 4-12) months. Three surviving patients were alive at their last follow-up (9, 12, and 12 months, respectively), whereas 2 patients with late-stage tumors survived 6 months and 13 months after TARFACT, respectively. After TARFACT, all patients showed significant reductions in tumor size: the mean length decreased from 6.7 ± 2.0 cm to 4.7 ± 1.8 cm (P = 0.007); and the mean width decreased from 5.0 ± 2.1 cm to 2.5 ± 0.7 cm (P = 0.041). NYHA functional class also improved: median (IQR) decreased from 3.0 (1.5) to 2.0 (1.0) (P = 0.038), Peak E-wave on echocardiography showed a mean increase from 64.4 ± 15.7 cm/s to 76.6 ± 18.6 cm/s (P = 0.008), and NT-pro BNP levels had a median (IQR) reduction from 115.7 (252.1) pg/mL to 55.0 (121.6) pg/mL (P = 0.043). Conclusions: TARFACT is a novel palliative treatment option for cardiac tumors, reducing accessible tumors and improving clinical symptoms in a preliminary group of patients. (Cardiac Tumors Interventional [Radio Frequency/Laser Ablation] Therapy [CTIH]; NCT02815553).

5.
JACS Au ; 4(9): 3537-3546, 2024 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-39328759

RESUMO

Precise transformations of natural products (NPs) can fine-tune their physicochemical properties while preserving inherently complex and evolutionarily optimized parent scaffolds. Here, we report an unprecedented lactone-to-lactam transformation on bilobalide, thus improving its stability and paving the way for biological exploration of previously inaccessible chemical space that is highly representative of the parent structure. This late-stage molecular editing of bilobalide enables facile access to a unique library of lactam analogues with altered pharmacology. Through phenotypic screening, we identify BB10 as a hit compound with unexpected inhibition of ferroptotic cell death. We further reveal that BB10 suppresses ferroptosis by restoring the expression of glutathione peroxidase 4 (GPX4) in brain cells. This study highlights that even subtle changes on NP scaffolds can confer new pharmacological properties, inspiring the exploration of simple yet critical transformations on complex NPs.

6.
Cell Rep Methods ; 3(5): 100458, 2023 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-37323568

RESUMO

Deep immunohistochemistry (IHC) is a nascent field in three-dimensional (3D) histology that seeks to achieve thorough, homogeneous, and specific staining of intact tissues for visualization of microscopic architectures and molecular compositions at large spatial scales. Despite the tremendous potential of deep IHC in revealing molecule-structure-function relationships in biology and establishing diagnostic and prognostic features for pathological samples in clinical practice, the complexities and variations in methodologies may hinder its use by interested users. We provide a unified framework of deep immunostaining techniques by discussing the theoretical considerations of the physicochemical processes involved, summarizing the principles applied in contemporary methods, advocating a standardized benchmarking scheme, and highlighting unaddressed issues and future directions. By providing the essential information to guide investigators in customizing immunolabeling pipelines, we also seek to facilitate the adoption of deep IHC for researchers to address a wide range of research questions.


Assuntos
Imuno-Histoquímica , Coloração e Rotulagem
7.
Front Cardiovasc Med ; 10: 1261172, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38162137

RESUMO

Background: Pompe disease (PD) is a rare, progressive, and autosomal recessive lysosomal storage disorder caused by mutations in the acid α-glucosidase gene. The clinical course and molecular mechanism of this disease in China have not been well defined. Methods: In this single-center cohort study, we investigated a total of 15 Chinese patients with Pompe disease to better understand the clinical manifestations, echocardiographic imaging and genetic characteristics in this population. Results: The median age of 15 patients at symptom onset was 5.07 months (1-24 months). The median age at diagnosis was 19.53 months (range: 3 to 109 months, n = 15). Average diagnostic delay was 13.46 months. None of the patients had received enzyme replacement therapy (ERT). Fifteen patients died at a median age of 24.80 months due to cardiorespiratory failure (range 3-120 months). Myasthenia symptoms and severe hypertrophic cardiomyopathy were universally present (15/15 = 100%). Global longitudinal strain (GLS) by echocardiography was significantly lower in these patients. After adjusting for gender, body surface area (BSA), left ventricular ejection fraction (LVEF), E/e'ratio, maximum left ventricular wall thickness (MLVWT), left ventricular posterior wall (LVPW), left ventricular outflow tract (LVOT)gradient, GLS was independently correlated with survival time (hazard ratio (HR) = 0.702, 95% confidence Interval (CI): 0.532-0.925, P = 0.012). In our cohort, we identified 4 novel GAA mutation: c.2102T > C (p.L701P), c.2006C > T (p.P669l), c.766T > A (p.Y256N), c.2405G > T (p.G802V). 12 patients were compound heterozygotes, and 4 homozygotes. Conclusions: Our study provides a comprehensive examination of PD clinical course and mutations of the GAA gene for patients in China. We showed clinical utility of echocardiography in quantifying heart involvement in patients with suspected PD. GLS can provide prognostic information for mortality prediction. We reported four novel mutations in the GAA gene for the first time. Our findings may improve early recognition of PD characteristics in Chinese patients.

8.
Heart ; 109(4): 289-296, 2023 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-36270787

RESUMO

OBJECTIVE: Echocardiography-guided Percutaneous IntraMyocardial Septal Radiofrequency Ablation (PIMSRA, Liwen procedure) is a novel treatment option for hypertrophic obstructive cardiomyopathy (HOCM). The impact of PIMSRA on myocardial mechanics is unknown. METHODS: Between October 2016 and June 2019, PIMSRA and 3-dimentional speckle tracking echocardiography were performed in 82 patients. Echocardiographic imaging, qualitative and quantitative clinical assessment were completed at baseline, immediately postprocedure and 1-year follow-up. RESULTS: There was a significant reduction in the peak left ventricular outflow tract (LVOT) gradients immediately following PIMSRA and at 1-year follow-up (resting gradients: from 83.50 (61.25) to 23.00 (41.75) mm Hg, p<0.001 and 13.50 (21.75) mm Hg, p<0.001, respectively; stress-induced gradients: from 118.25 (96.02) to 47.00 (74.50) mm Hg (1 year), p<0.001). There was an improvement in exercise time on stress echocardiography (p<0.001) and distance by 6 min walk test (p=0.034). Immediately after PIMSRA, there was a significant reduction in radial and circumferential strain in the ablated segments (p<0.001), with no change of longitudinal strain. At 1-year follow-up, the radial and circumferential strain recovered in the ablated segments. Meanwhile, left ventricular regional and global longitudinal strain had improved significantly (p<0.05). CONCLUSIONS: PIMSRA is an effective treatment for symptomatic HOCM that resulted in a sustained improvement in exercise capacity, a persistent decrease in LVOT gradient, and a measurable increase in myocardial contractile function. TRIAL REGISTRATION NUMBER: NCT04777188.


Assuntos
Cardiomiopatia Hipertrófica , Ablação por Cateter , Ablação por Radiofrequência , Humanos , Cardiomiopatia Hipertrófica/diagnóstico por imagem , Cardiomiopatia Hipertrófica/cirurgia , Ablação por Cateter/métodos , Ecocardiografia/métodos , Septos Cardíacos/diagnóstico por imagem , Septos Cardíacos/cirurgia , Resultado do Tratamento
9.
Commun Biol ; 4(1): 656, 2021 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-34079050

RESUMO

Pharmacological reversal of brain aging is a long-sought yet challenging strategy for the prevention and treatment of age-related neurodegeneration, due to the diverse cell types and complex cellular pathways impacted by the aging process. Here, we report the genome-wide reversal of transcriptomic aging signatures in multiple major brain cell types, including glial and mural cells, by systemic glucagon-like peptide-1 receptor (GLP-1R) agonist (GLP-1RA) treatment. The age-related expression changes reversed by GLP-1RA encompass both shared and cell type-specific functional pathways that are implicated in aging and neurodegeneration. Concomitantly, Alzheimer's disease (AD)-associated transcriptomic signature in microglia that arises from aging is reduced. These results show the feasibility of reversing brain aging by pharmacological means, provide mechanistic insights into the neurological benefits of GLP-1RAs, and imply that GLP-1R agonism may be a generally applicable pharmacological intervention for patients at risk of age-related neurodegeneration.


Assuntos
Encéfalo/efeitos dos fármacos , Senescência Celular/efeitos dos fármacos , Senescência Celular/genética , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Neuroglia/efeitos dos fármacos , Envelhecimento/efeitos dos fármacos , Envelhecimento/genética , Doença de Alzheimer/genética , Animais , Encéfalo/citologia , Encéfalo/metabolismo , Exenatida/farmacologia , Estudos de Viabilidade , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Doenças Neurodegenerativas/tratamento farmacológico , Doenças Neurodegenerativas/genética , Neuroglia/metabolismo , Transcriptoma/efeitos dos fármacos , Transcriptoma/genética
10.
Oncogene ; 40(48): 6590-6600, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34615997

RESUMO

Ribosome biogenesis plays a pivotal role in tumorigenesis by supporting robust protein translation. We investigate the functional and molecular mechanism of Zinc finger protein 545 (ZNF545), a transcriptional repressor for ribosomal RNA (rRNA), in colorectal cancer (CRC). ZNF545 was silenced in CRC compared to adjacent normal tissues (P < 0.0001), implying a tumor-suppressive role. Colon-specific Znf545 knockout in mice accelerated CRC in ApcMin/+ and azoxymethane/dextran sulfate sodium-induced CRC. Mechanistically, we demonstrated that ZNF545 uses its two zinc finger clusters to bind to minimal rDNA promoter, where it assembled transcriptional repressor complex by interacting with KAP1. Znf545 deletion in mouse embryonic fibroblasts not only increased rRNA transcription rate and the nucleolar size and number but also altered the nucleolar composition and architecture with an increased number of fibrillar centers surrounded by net-like dense fibrillar components. Consequently, Znf545 deletion promoted the gene expression of translation machinery, protein translation, and cell growth. Consistent with its tumor-suppressive role, ZNF545 overexpression in CRC cells induced growth arrest and apoptosis. Finally, administration of rRNA synthesis inhibitor, CX-5461, inhibited CRC development in Znf545Δ/ΔApcMin/+ mice. In conclusion, ZNF545 suppresses CRC through repressing rRNA transcription and protein translation. Targeting rRNA biosynthesis in ZNF545-silenced tumors is a potential therapeutic strategy for CRC.


Assuntos
Carcinogênese/patologia , Neoplasias Colorretais/patologia , Proteínas Nucleares/fisiologia , Biossíntese de Proteínas , RNA Ribossômico/metabolismo , Ribossomos/metabolismo , Animais , Azoximetano/toxicidade , Carcinogênese/genética , Carcinogênese/metabolismo , Comunicação Celular , Nucléolo Celular/genética , Nucléolo Celular/metabolismo , Proliferação de Células , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Fibroblastos/metabolismo , Fibroblastos/patologia , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , RNA Ribossômico/genética
11.
ACS Cent Sci ; 7(5): 792-802, 2021 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-34075346

RESUMO

The outbreak of coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is a global threat to human health. Using a multidisciplinary approach, we identified and validated the hepatitis C virus (HCV) protease inhibitor simeprevir as an especially promising repurposable drug for treating COVID-19. Simeprevir potently reduces SARS-CoV-2 viral load by multiple orders of magnitude and synergizes with remdesivir in vitro. Mechanistically, we showed that simeprevir not only inhibits the main protease (Mpro) and unexpectedly the RNA-dependent RNA polymerase (RdRp) but also modulates host immune responses. Our results thus reveal the possible anti-SARS-CoV-2 mechanism of simeprevir and highlight the translational potential of optimizing simeprevir as a therapeutic agent for managing COVID-19 and future outbreaks of CoV.

12.
EBioMedicine ; 53: 102701, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32151798

RESUMO

BACKGROUND: Chromosomal instability plays an important part in cancer, but its genetic basis in liver tumorigenesis remains largely unclear. We aimed to characterize the mechanistic significance and clinical implication of mitotic regulator microtubule-associated protein 9 (MAP9) in hepatocellular carcinoma (HCC). METHODS: The biological functions of MAP9 were determined by in vitro tumorigenicity assays. Systematic MAP9 knockout mouse (MAP9∆/∆) and hepatocyte-specific MAP9 knockout mouse (MAP9∆/∆hep) were generated to confirm the role of MAP9 in HCC. The clinical impact of MAP9 was assessed in primary HCC tissue samples. FINDINGS: We found that MAP9 was frequently silenced in HCC tissue samples. The transcriptional silence of MAP9 in liver cancer cell lines and tissue samples was mediated by its promoter hypermethylation. MAP9 promoter hypermethylation or downregulation was associated with poor survival and recurrence in patients with HCC. Mechanistically, ectopic expression of MAP9 in LO2 and HepG2 cell lines impaired cell proliferation, colony formation, migration and invasion, and induced cell apoptosis and cycle arrest, whereas knockdown of MAP9 in Miha cell line showed the opposite effects. We found that MAP9∆/∆ mice spontaneously developed a liver hyperplastic nodule and MAP9∆/∆hep accelerated diethylnitrosamine-induced HCC formation. The tumour suppressive effect of MAP9 in HCC was mediated by downregulating excision repair cross-complementation group 3 (ERCC3), a nucleotide excision repair gene. Restoration of ERCC3 expression possessed an oncogenic potency and abrogated the tumour suppressive effects of MAP9. INTERPRETATION: MAP9 is a novel tumour suppressor in HCC by inhibiting ERCC3 expression, and serves as a prognostic factor in HCC patients.


Assuntos
Biomarcadores Tumorais/genética , Carcinogênese/genética , Carcinoma Hepatocelular/metabolismo , DNA Helicases/genética , Proteínas de Ligação a DNA/genética , Neoplasias Hepáticas/metabolismo , Proteínas Associadas aos Microtúbulos/genética , Animais , Biomarcadores Tumorais/metabolismo , Carcinogênese/metabolismo , Carcinogênese/patologia , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Movimento Celular , Proliferação de Células , DNA Helicases/metabolismo , Proteínas de Ligação a DNA/metabolismo , Regulação para Baixo , Inativação Gênica , Células Hep G2 , Hepatócitos/metabolismo , Hepatócitos/fisiologia , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Associadas aos Microtúbulos/metabolismo , Células Tumorais Cultivadas
13.
Clin Cancer Res ; 26(3): 746-757, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31662330

RESUMO

PURPOSE: Chromosomal instability (CIN) is a common phenomenon in colorectal cancer, but its role and underlying cause remain unknown. We have identified that mitotic regulator microtubule-associated protein 9 (MAP9) is a critical regulator of CIN in colorectal cancer. We thus studied the effect of MAP9 loss on colorectal cancer in Map9-knockout mice and in cell lines. EXPERIMENTAL DESIGN: We generated colon epithelial-specific Map9-knockout mice and evaluated colorectal cancer development. Effect of Map9 knockout on colorectal cancer progression was determined in chemical or ApcMin /+ -induced colorectal cancer. Molecular mechanism of MAP9 was determined using spectral karyotyping, microtubule assays, and whole-genome sequencing (WGS). Clinical significance of MAP9 was examined in 141 patients with CRC. RESULTS: Spontaneous colonic tumors (9.1%) were developed in colon epithelium-specific Map9-knockout mice at 17 months, but none was observed in wild-type littermates. Map9 deletion accelerated colorectal cancer formation both in ApcMin /+ mice and azoxymethane-treated mice, and reduced survival in ApcMin /+ mice. Mechanistically, MAP9 stabilized microtubules and mediated mitotic spindle assembly. MAP9 also maintained the spindle pole integrity and protected K-fiber from depolymerization at spindle poles. MAP9 loss induced severe mitosis failure, chromosome segregation errors, and aneuploidy, leading to transformation of normal colon epithelial cells. WGS confirmed enhanced CIN in intestinal tumors from Map9 knockout ApcMin /+ mice. In patients with colorectal cancer, MAP9 was frequently silenced and its downregulation was associated with poor survival. CONCLUSIONS: MAP9 is a microtubule stabilizer that contributes to spindle stability and inhibits colorectal tumorigenesis, supporting the role of MAP9 as a tumor suppressor for preventing CIN in colorectal cancer.


Assuntos
Carcinogênese/patologia , Instabilidade Cromossômica , Neoplasias Colorretais/mortalidade , Proteínas Associadas aos Microtúbulos/metabolismo , Mitose , Aneuploidia , Animais , Apoptose , Azoximetano/toxicidade , Carcinogênese/induzido quimicamente , Carcinogênese/genética , Carcinógenos/toxicidade , Proliferação de Células , Neoplasias Colorretais/induzido quimicamente , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Humanos , Camundongos , Camundongos Knockout , Proteínas Associadas aos Microtúbulos/genética , Prognóstico , Taxa de Sobrevida , Células Tumorais Cultivadas
14.
Nat Commun ; 11(1): 4413, 2020 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-32887883

RESUMO

The molecular signatures of cells in the brain have been revealed in unprecedented detail, yet the ageing-associated genome-wide expression changes that may contribute to neurovascular dysfunction in neurodegenerative diseases remain elusive. Here, we report zonation-dependent transcriptomic changes in aged mouse brain endothelial cells (ECs), which prominently implicate altered immune/cytokine signaling in ECs of all vascular segments, and functional changes impacting the blood-brain barrier (BBB) and glucose/energy metabolism especially in capillary ECs (capECs). An overrepresentation of Alzheimer disease (AD) GWAS genes is evident among the human orthologs of the differentially expressed genes of aged capECs, while comparative analysis revealed a subset of concordantly downregulated, functionally important genes in human AD brains. Treatment with exenatide, a glucagon-like peptide-1 receptor agonist, strongly reverses aged mouse brain EC transcriptomic changes and BBB leakage, with associated attenuation of microglial priming. We thus revealed transcriptomic alterations underlying brain EC ageing that are complex yet pharmacologically reversible.


Assuntos
Envelhecimento/patologia , Barreira Hematoencefálica , Encéfalo/fisiopatologia , Células Endoteliais/metabolismo , Exenatida/farmacologia , Doença de Alzheimer/fisiopatologia , Animais , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/fisiopatologia , Capilares/metabolismo , Células Cultivadas , Humanos , Camundongos , Microglia/efeitos dos fármacos , Doenças Neurodegenerativas/fisiopatologia , Transcriptoma/efeitos dos fármacos
15.
Cancer Res ; 79(16): 4086-4098, 2019 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-31239268

RESUMO

Tripartite motif (TRIM) family proteins participate in a variety of important cellular processes, including apoptosis, cell-cycle arrest, DNA repair, and senescence. In this study, we demonstrated that a novel TRIM family member, TRIM67, was commonly silenced in colorectal cancer and its downregulation was associated with poor survival. Trim67 knockout in ApcMin/+ mice increased the incidence, multiplicity, and burden of colorectal tumors. Similarly, colon-specific knockout of Trim67 significantly accelerated azoxymethane-induced colorectal cancer in mice. RNA sequencing revealed that the antitumor effect of TRIM67 was mediated by activation of the p53 signaling pathway. TRIM67 interacted directly with the C-terminus of p53, inhibiting p53 degradation by its ubiquitin ligase MDM2. TRIM67 was also a transcriptional target of p53; upon cellular stress, p53 bound to the TRIM67 promoter and induced significant upregulation of TRIM67, thereby forming a TRIM67/p53 self-amplifying loop that boosts p53-induced cell growth inhibition and apoptosis. Consequently, loss of this p53-positive regulatory program profoundly compromised p53-mediated responses to chemotherapy-induced DNA damage. Dampened p53 response was also observed in tumors of Trim67 knockout mice and Trim67 knockout embryonic fibroblasts. TRIM67 reactivation restored p53 activation and sensitized colorectal cancer cells to chemotherapy in vitro and in vivo. TRIM67 thus functions as a pivotal tumor suppressor in colorectal cancer and is a potential target for improving chemotherapy responsiveness. SIGNIFICANCE: The TRIM67/p53 axis represents a novel therapeutic target that could be harnessed to improve chemotherapy efficacy in colorectal cancer expressing wild-type p53 but with repressed p53 signaling.


Assuntos
Neoplasias Colorretais/patologia , Proteínas do Citoesqueleto/genética , Proteínas com Motivo Tripartido/genética , Proteína Supressora de Tumor p53/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Estudos de Casos e Controles , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/mortalidade , Proteínas do Citoesqueleto/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Camundongos Endogâmicos BALB C , Camundongos Knockout , Camundongos Transgênicos , Pessoa de Meia-Idade , Neoplasias Experimentais/induzido quimicamente , Neoplasias Experimentais/genética , Regiões Promotoras Genéticas , Proteínas com Motivo Tripartido/metabolismo , Proteína Supressora de Tumor p53/genética , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Sci Rep ; 4: 4784, 2014 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-24759264

RESUMO

Recreation of neural network in vitro with designed topology is a valuable tool to decipher how neurons behave when interacting in hierarchical networks. In this study, we developed a simple and effective platform to pattern primary neurons in array formats for interrogation of neural circuitry with single cell resolution. Unlike many surface-chemistry-based patterning methods, our NeuroArray technique is specially designed to accommodate neuron's polarized morphologies to make regular arrays of cells without restricting their neurite outgrowth, and thus allows formation of freely designed, well-connected, and spontaneously active neural network. The NeuroArray device was based on a stencil design fabricated using a novel sacrificial-layer-protected PDMS molding method that enables production of through-structures in a thin layer of PDMS with feature sizes as small as 3 µm. Using the NeuroArray along with calcium imaging, we have successfully demonstrated large-scale tracking and recording of neuronal activities, and used such data to characterize the spiking dynamics and transmission within a diode-like neural network. Essentially, the NeuroArray is a universal patterning platform designed for, but not limited to neuron cells. With little adaption, it can be readily interfaced with other interrogation modalities for high-throughput drug testing, and for building neuron culture based live computational devices.


Assuntos
Análise em Microsséries/métodos , Rede Nervosa , Neurônios/fisiologia , Animais , Técnicas de Cultura de Células , Análise em Microsséries/instrumentação , Células Piramidais/fisiologia , Ratos , Análise de Célula Única
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