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1.
J Biol Chem ; 300(2): 105629, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38199563

RESUMO

In contrast to stage-specific transcription factors, the role of ubiquitous transcription factors in neuronal development remains a matter of scrutiny. Here, we demonstrated that a ubiquitous factor NF-Y is essential for neural progenitor maintenance during brain morphogenesis. Deletion of the NF-YA subunit in neural progenitors by using nestin-cre transgene in mice resulted in significant abnormalities in brain morphology, including a thinner cerebral cortex and loss of striatum during embryogenesis. Detailed analyses revealed a progressive decline in multiple neural progenitors in the cerebral cortex and ganglionic eminences, accompanied by induced apoptotic cell death and reduced cell proliferation. In neural progenitors, the NF-YA short isoform lacking exon 3 is dominant and co-expressed with cell cycle genes. ChIP-seq analysis from the cortex during early corticogenesis revealed preferential binding of NF-Y to the cell cycle genes, some of which were confirmed to be downregulated following NF-YA deletion. Notably, the NF-YA short isoform disappears and is replaced by its long isoform during neuronal differentiation. Forced expression of the NF-YA long isoform in neural progenitors resulted in a significant decline in neuronal count, possibly due to the suppression of cell proliferation. Collectively, we elucidated a critical role of the NF-YA short isoform in maintaining neural progenitors, possibly by regulating cell proliferation and apoptosis. Moreover, we identified an isoform switch in NF-YA within the neuronal lineage in vivo, which may explain the stage-specific role of NF-Y during neuronal development.


Assuntos
Fator de Ligação a CCAAT , Córtex Cerebral , Animais , Camundongos , Fator de Ligação a CCAAT/genética , Fator de Ligação a CCAAT/metabolismo , Córtex Cerebral/citologia , Córtex Cerebral/crescimento & desenvolvimento , Córtex Cerebral/metabolismo , Regulação da Expressão Gênica , Neurogênese , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Fatores de Transcrição/metabolismo
2.
Environ Pollut ; 343: 123158, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38123117

RESUMO

Estuaries, which serve as vital links between land and coastal ecosystems, play a significant part in facilitating the transfer of plastic waste from the land to the ocean. In this research, we examined the prevalence, characteristics, and ecological risks of microplastics (MPs) in the extensively urbanized Cochin Estuarine System (CES), India. Additionally, it represents one of the initial evidence-based examinations of MPs ingestion by jellyfish in Indian waters, focusing on Acromitus flagellatus, Blackfordia virginica, and Pleurobrachia pileus species. The abundance of MPs found in the surface water of the Cochin Estuarine System (CES) varied between 14.44 ± 9 to 30 ± 15.94 MP/m3, with an average of 21.6 ± 11 MP/m3. In both surface waters and jellyfish from the Cochin Estuarine System (CES), fibers were the most prevalent type of MPs, with polyethylene (PE), polypropylene (PP), and polyamide (PA) being the most common polymer varieties. To evaluate the current levels of MPs and their effect on the CES, the Pollution Load Index (PLI), Potential Ecological Risk Index (PERI), and Polymeric Risk Index (H) were utilized. The high PLIestuary values (20.33), high Hestuary values (234.02), and extreme PERIestuary value (1646.06) indicate that the CES is facing an extreme ecological risk. Among the 280 jellyfish individuals examined, 118 (42.14%) were recognized to contain MPs with an average of 1.54 ± 2.68 MPs/individual. Pearson bivariate analysis revealed a significant correlation between the jellyfish bell size and number of plastics per individual. Comparison between jellyfish species revealed, the majority (66%) of the MPs identified in jellyfish were from A. flagellatus and 44 among the 50 jellyfish examined (88%) had MPs. These findings suggest that A. flagellatus may be a potential sink for MPs and may be utilized to be a bioindicator for monitoring MPs contamination in estuarine systems, aiding in future plastic pollution mitigation efforts.


Assuntos
Microplásticos , Poluentes Químicos da Água , Humanos , Microplásticos/análise , Plásticos/análise , Estuários , Ecossistema , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Polímeros , Medição de Risco
3.
J Pharm Bioallied Sci ; 15(Suppl 1): S175-S179, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37654328

RESUMO

Introduction: The orthodontic appliances have been known to accelerate enamel loss due to various reasons. Since there are few studies supporting the role of the nano-HAP in the mineralization of the demineralized tooth surfaces, the current study compared nano-HAP's capacity to remineralize the demineralized enamel layer surrounding braces at various concentration levels. Materials and Procedures: This investigation involved 60 healthy permanent premolars that had just been excised. All specimens had 3M-Unitek brackets glued to their buccal surfaces. The samples were artificially demineralized and divided into three groups. The control group, Toothpaste ApaCare, and ApaCareTM varnish. Before and after remineralization, selected samples from each group were analyzed using a "Scanning Electron Microscope (SEM)" and evaluated using "Energy Dispersive X-Ray Analysis (EDAX)." Spectrometer and profilometer were used for the study of surface and the color. Statistics were used to analyze the outcomes. The threshold for significance was fixed at 0.05. Results: After remineralization by nano-HAP, there was a significant rise (P < 0.001) in both calcium and phosphorus levels. This was picked up by EDAX, and SEM verified it. When compared to the control group, the nano-HAP application greatly improved the color measurements in the study groups (P < 0.001), and it also resulted in a significant decrease in surface roughness (P < 0.001). Conclusion: Our study's results showed that nano-HAP could be successful in restoring demineralized enamel around brackets, reducing the surface roughness and color of the enamel surface.

4.
Aust J Gen Pract ; 51(11): 827-830, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36309994

RESUMO

BACKGROUND: Acute open wounds constitute a significant part of general practice. With an expanding global market of dressing products, selection of wound dressings remains an area of concern among doctors entering general practice. OBJECTIVE: The aim of this article is to describe a practical guide for choosing appropriate dressings when treating acute open wounds in general practice. DISCUSSION: Although dressing is an essential element of standard wound care, it is important to remember that dressing alone does not heal the wound. Judicious selection of dressings based on wound characteristics, physical properties of dressings and their costs, shelf life and availability are important for delivering appropriate care towards timely healing of acute wounds.


Assuntos
Bandagens , Medicina Geral , Humanos , Cicatrização
5.
MAbs ; 14(1): 2095949, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35867844

RESUMO

Cluster of differentiation 38 (CD38) is an ecto-enzyme expressed primarily on immune cells that metabolize nicotinamide adenine dinucleotide (NAD+) to adenosine diphosphate ribose or cyclic ADP-ribose and nicotinamide. Other substrates of CD38 include nicotinamide adenine dinucleotide phosphate and nicotinamide mononucleotide, a critical NAD+ precursor in the salvage pathway. NAD+ is an important coenzyme involved in several metabolic pathways and is a required cofactor for the function of sirtuins (SIRTs) and poly (adenosine diphosphate-ribose) polymerases. Declines in NAD+ levels are associated with metabolic and inflammatory diseases, aging, and neurodegenerative disorders. To inhibit CD38 enzyme activity and boost NAD+ levels, we developed TNB-738, an anti-CD38 biparatopic antibody that pairs two non-competing heavy chain-only antibodies in a bispecific format. By simultaneously binding two distinct epitopes on CD38, TNB-738 potently inhibited its enzymatic activity, which in turn boosted intracellular NAD+ levels and SIRT activities. Due to its silenced IgG4 Fc, TNB-738 did not deplete CD38-expressing cells, in contrast to the clinically available anti-CD38 antibodies, daratumumab, and isatuximab. TNB-738 offers numerous advantages compared to other NAD-boosting therapeutics, including small molecules, and supplements, due to its long half-life, specificity, safety profile, and activity. Overall, TNB-738 represents a novel treatment with broad therapeutic potential for metabolic and inflammatory diseases associated with NAD+ deficiencies.Abbreviations: 7-AAD: 7-aminoactinomycin D; ADCC: antibody dependent cell-mediated cytotoxicity; ADCP: antibody dependent cell-mediated phagocytosis; ADPR: adenosine diphosphate ribose; APC: allophycocyanin; cADPR: cyclic ADP-ribose; cDNA: complementary DNA; BSA: bovine serum albumin; CD38: cluster of differentiation 38; CDC: complement dependent cytotoxicity; CFA: Freund's complete adjuvant; CHO: Chinese hamster ovary; CCP4: collaborative computational project, number 4; COOT: crystallographic object-oriented toolkit; DAPI: 4',6-diamidino-2-phenylindole; DNA: deoxyribonucleic acid; DSC: differential scanning calorimetry; 3D: three dimensional; εNAD+: nicotinamide 1,N6-ethenoadenine dinucleotide; ECD: extracellular domain; EGF: epidermal growth factor; FACS: fluorescence activated cell sorting; FcγR: Fc gamma receptors; FITC: fluorescein isothiocyanate; HEK: human embryonic kidney; HEPES: 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid; IgG: immunoglobulin; IFA: incomplete Freund's adjuvant; IFNγ: Interferon gamma; KB: kinetic buffer; kDa: kilodalton; KEGG: kyoto encyclopedia of genes and genomes; LDH: lactate dehydrogenase; M: molar; mM: millimolar; MFI: mean fluorescent intensity; NA: nicotinic acid; NAD: nicotinamide adenine dinucleotide; NADP: nicotinamide adenine dinucleotide phosphate; NAM: nicotinamide; NGS: next-generation sequencing; NHS/EDC: N-Hydroxysuccinimide/ ethyl (dimethylamino propyl) carbodiimide; Ni-NTA: nickel-nitrilotriacetic acid; nL: nanoliter; NK: natural killer; NMN: nicotinamide mononucleotide; OD: optical density; PARP: poly (adenosine diphosphate-ribose) polymerase; PBS: phosphate-buffered saline; PBMC: peripheral blood mononuclear cell; PDB: protein data bank; PE: phycoerythrin; PISA: protein interfaces, surfaces, and assemblies: PK: pharmacokinetics; mol: picomolar; RNA: ribonucleic acid; RLU: relative luminescence units; rpm: rotations per minute; RU: resonance unit; SEC: size exclusion chromatography; SEM: standard error of the mean; SIRT: sirtuins; SPR: surface plasmon resonance; µg: microgram; µM: micromolar; µL: microliter.


Assuntos
NAD , Sirtuínas , Adenosina Difosfato Ribose/química , Adenosina Difosfato Ribose/metabolismo , Animais , Células CHO , Cricetinae , Cricetulus , ADP-Ribose Cíclica , Humanos , Imunoglobulina G , Leucócitos Mononucleares/metabolismo , NAD/química , NAD/metabolismo , NADP , Niacinamida , Mononucleotídeo de Nicotinamida , Ribose
7.
Cell Rep ; 39(1): 110595, 2022 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-35385726

RESUMO

Bioinformatic analysis of 94 patient-derived xenografts (PDXs), cell lines, and organoids (PCOs) identifies three intrinsic transcriptional subtypes of metastatic castration-resistant prostate cancer: androgen receptor (AR) pathway + prostate cancer (PC) (ARPC), mesenchymal and stem-like PC (MSPC), and neuroendocrine PC (NEPC). A sizable proportion of castration-resistant and metastatic stage PC (M-CRPC) cases are admixtures of ARPC and MSPC. Analysis of clinical datasets and mechanistic studies indicates that MSPC arises from ARPC as a consequence of therapy-induced lineage plasticity. AR blockade with enzalutamide induces (1) transcriptional silencing of TP53 and hence dedifferentiation to a hybrid epithelial and mesenchymal and stem-like state and (2) inhibition of BMP signaling, which promotes resistance to AR inhibition. Enzalutamide-tolerant LNCaP cells re-enter the cell cycle in response to neuregulin and generate metastasis in mice. Combined inhibition of HER2/3 and AR or mTORC1 exhibits efficacy in models of ARPC and MSPC or MSPC, respectively. These results define MSPC, trace its origin to therapy-induced lineage plasticity, and reveal its sensitivity to HER2/3 inhibition.


Assuntos
Antineoplásicos , Neoplasias de Próstata Resistentes à Castração , Transdução de Sinais , Animais , Antineoplásicos/farmacologia , Benzamidas , Carcinoma Neuroendócrino , Linhagem Celular Tumoral , Plasticidade Celular/efeitos dos fármacos , Plasticidade Celular/fisiologia , Resistencia a Medicamentos Antineoplásicos , Humanos , Masculino , Camundongos , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Nitrilas , Feniltioidantoína , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/genética , Neoplasias de Próstata Resistentes à Castração/metabolismo , Receptores Androgênicos/efeitos dos fármacos , Receptores Androgênicos/metabolismo , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/fisiologia
8.
Sci Rep ; 10(1): 21714, 2020 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-33303918

RESUMO

A heterotrimeric transcription factor NF-Y is crucial for cell-cycle progression in various types of cells. In contrast, studies using NF-YA knockout mice have unveiled its essential role in endoplasmic reticulum (ER) homeostasis in neuronal cells. However, whether NF-Y modulates a different transcriptome to mediate distinct cellular functions remains obscure. Here, we knocked down NF-Y in two types of neuronal cells, neuro2a neuroblastoma cells and mouse brain striatal cells, and performed gene expression profiling. We found that down-regulated genes preferentially contained NF-Y-binding motifs in their proximal promoters, and notably enriched genes related to ER functions rather than those for cell cycle. This contrasts with the profiling data of HeLa and embryonic stem cells in which distinct down-regulation of cell cycle-related genes was observed. Clustering analysis further identified several functional clusters where populations of the down-regulated genes were highly distinct. Further analyses using chromatin immunoprecipitation and RNA-seq data revealed that the transcriptomic difference was not correlated with DNA binding of NF-Y but with splicing of NF-YA. These data suggest that neuronal cells have a different type of transcriptome in which ER-related genes are dominantly modulated by NF-Y, and imply that NF-YA splicing alteration could be involved in this cell type-specific gene modulation.


Assuntos
Fator de Ligação a CCAAT/genética , Fator de Ligação a CCAAT/fisiologia , Ciclo Celular/genética , Neurônios/fisiologia , Transcriptoma/genética , Processamento Alternativo , Animais , Retículo Endoplasmático/genética , Perfilação da Expressão Gênica , Células HeLa , Homeostase/genética , Humanos , Camundongos , Neurônios/metabolismo , Splicing de RNA
9.
Open Forum Infect Dis ; 7(5): ofaa142, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32494579

RESUMO

Treatment for Candida infective endocarditis (IE) has not been extensively studied in the setting of rising injection drug use. There were 12 cases of Candida IE at the Maine Medical Center between 2013 and 2018. The patient characteristics, treatment regimens, and outcomes were retrospectively analyzed.

11.
Nat Commun ; 10(1): 2571, 2019 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-31189930

RESUMO

While the antiandrogen enzalutamide (Enz) extends the castration resistant prostate cancer (CRPC) patients' survival an extra 4.8 months, it might also result in some adverse effects via inducing the neuroendocrine differentiation (NED). Here we found that lncRNA-p21 is highly expressed in the NEPC patients derived xenograft tissues (NEPC-PDX). Results from cell lines and human clinical sample surveys also revealed that lncRNA-p21 expression is up-regulated in NEPC and Enz treatment could increase the lncRNA-p21 to induce the NED. Mechanism dissection revealed that Enz could promote the lncRNA-p21 transcription via altering the androgen receptor (AR) binding to different androgen-response-elements, which switch the EZH2 function from histone-methyltransferase to non-histone methyltransferase, consequently methylating the STAT3 to promote the NED. Preclinical studies using the PDX mouse model proved that EZH2 inhibitor could block the Enz-induced NED. Together, these results suggest targeting the Enz/AR/lncRNA-p21/EZH2/STAT3 signaling may help urologists to develop a treatment for better suppression of the human CRPC progression.


Assuntos
Antagonistas de Androgênios/efeitos adversos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Tumores Neuroendócrinos/patologia , Feniltioidantoína/análogos & derivados , Neoplasias de Próstata Resistentes à Castração/patologia , RNA Longo não Codificante/metabolismo , Animais , Benzamidas , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Linhagem Celular Tumoral , Progressão da Doença , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Humanos , Masculino , Camundongos , Camundongos SCID , Células Neuroendócrinas/efeitos dos fármacos , Células Neuroendócrinas/patologia , Tumores Neuroendócrinos/tratamento farmacológico , Tumores Neuroendócrinos/genética , Nitrilas , Feniltioidantoína/efeitos adversos , Próstata/citologia , Próstata/efeitos dos fármacos , Próstata/patologia , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/genética , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Regulação para Cima/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Mol Imaging Biol ; 21(1): 86-94, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-29748904

RESUMO

PURPOSE: Androgen receptor (AR) signaling affects prostate cancer (PCa) growth, metabolism, and progression. Often, PCa progresses from androgen-sensitive to castration-resistant prostate cancer (CRPC) following androgen-deprivation therapy. Clinicopathologic and genomic characterizations of CRPC tumors lead to subdividing CRPC into two subtypes: (1) AR-dependent CRPC containing dysregulation of AR signaling alterations in AR such as amplification, point mutations, and/or generation of splice variants in the AR gene; and (2) an aggressive variant PCa (AVPC) subtype that is phenotypically similar to small cell prostate cancer and is defined by chemotherapy sensitivity, gain of neuroendocrine or pro-neural marker expression, loss of AR expression, and combined alterations of PTEN, TP53, and RB1 tumor suppressors. Previously, we reported patient-derived xenograft (PDX) animal models that contain characteristics of these CRPC subtypes. In this study, we have employed the PDX models to test metabolic alterations in the CRPC subtypes. PROCEDURES: Mass spectrometry and nuclear magnetic resonance analysis along with in vivo hyperpolarized 1-[13C]pyruvate spectroscopy experiments were performed on prostate PDX animal models. RESULTS: Using hyperpolarized 1-[13C]pyruvate conversion to 1-[13C]lactate in vivo as well as lactate measurements ex vivo, we have found increased lactate production in AR-dependent CRPC PDX models even under low-hormone levels (castrated mouse) compared to AR-negative AVPC PDX models. CONCLUSIONS: Our analysis underscores the potential of hyperpolarized metabolic imaging in determining the underlying biology and in vivo phenotyping of CRPC.


Assuntos
Ácido Láctico/metabolismo , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética/métodos , Neoplasias de Próstata Resistentes à Castração/diagnóstico , Ácido Pirúvico/metabolismo , Receptores Androgênicos/metabolismo , Animais , Modelos Animais de Doenças , Progressão da Doença , Xenoenxertos , Humanos , Aumento da Imagem/métodos , Ácido Láctico/análise , Masculino , Camundongos , Camundongos SCID , Invasividade Neoplásica , Próstata/química , Próstata/diagnóstico por imagem , Próstata/metabolismo , Próstata/patologia , Neoplasias de Próstata Resistentes à Castração/metabolismo , Neoplasias de Próstata Resistentes à Castração/patologia , Ácido Pirúvico/análise , Transdução de Sinais/fisiologia , Células Tumorais Cultivadas
14.
Cancer ; 124(18): 3693-3705, 2018 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-30289966

RESUMO

BACKGROUND: Patients with advanced primary and recurrent salivary duct carcinoma (SDC), a rare and lethal malignancy, have limited therapeutic options. Novel small-molecule agents aimed at targeting critical signaling associated with SDC tumorigenesis may lead to new therapeutic options for patients with these tumors. The human epidermal growth factor receptor 2 (HER2)/phosphoinositide 3-kinase (PI3K) axis, an important oncogenic pathway, has been targeted for therapy in several solid tumors. Currently, little is known about the role and clinical implications of alterations of the HER2/PI3K pathway in patients with SDC. METHODS: The authors investigated the clinicopathologic features, genetic alterations, and expression of key members of the HER2/PI3K pathway in 43 primary tumors and conducted in vitro functional and targeted drug-response analyses on cell lines derived from salivary epithelial carcinomas. RESULTS: In primary tumors, loss of phosphatase and tensin homolog (PTEN) expression was identified in 22 of 43 tumors (51%), overexpression of HER2 was observed in 12 of 43 tumors (28%), and phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA) mutations were identified in 12 of 43 tumors (28%). Phosphorylated protein kinase B (p-AKT) was highly expressed in most tumors. Most tumors (70%) displayed mutually exclusive alterations of PI3K members, whereas 8 tumors (19%) had 2 or more concurrent abnormalities. In vitro studies demonstrated a direct association between PTEN loss and PI3K pathway activation and evidence of response to combined PI3Kα and PI3Kß and/or pan-PI3K inhibitors. CONCLUSIONS: The current analyses reveal frequent PTEN loss and mutually exclusive alterations of key PI3K pathway members in SDC and demonstrate in vitro evidence of a response to pan-PI3K inhibitors. These results provide a framework for a biomarker-based substratification of patients with SDC in future targeted therapy. Cancer 2018;124:3523-32. © 2018 American Cancer Society.


Assuntos
Carcinoma Ductal/terapia , Terapia de Alvo Molecular/métodos , PTEN Fosfo-Hidrolase/genética , Fosfatidilinositol 3-Quinases/genética , Receptor ErbB-2/genética , Neoplasias das Glândulas Salivares/terapia , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Carcinoma Ductal/genética , Classe I de Fosfatidilinositol 3-Quinases/genética , Classe I de Fosfatidilinositol 3-Quinases/metabolismo , Deleção de Genes , Frequência do Gene , Células HEK293 , Humanos , Mutação , Fosfatidilinositol 3-Quinases/metabolismo , Receptor ErbB-2/metabolismo , Medição de Risco , Neoplasias das Glândulas Salivares/genética , Transdução de Sinais/genética , Transcriptoma , Células Tumorais Cultivadas
15.
Front Oncol ; 8: 69, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29600194

RESUMO

Combined loss of tumor suppressors (TSPs), PTEN, TP53, and RB1, is highly associated with small cell carcinoma of prostate phenotype. Recent genomic studies of human tumors as well as analyses in mouse genetic models have revealed a unique role for these TSPs in dictating epithelial lineage plasticity-a phenomenon that plays a critical role in the development of aggressive variant prostate cancer (PCa) and associated androgen therapy resistance. Here, we summarize recently published key observations on this topic and hypothesize a possible mechanism by which concurrent loss of TSPs could potentially regulate the PCa disease phenotype.

16.
Dev Cell ; 41(5): 467-480.e3, 2017 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-28586644

RESUMO

Prostate cancer (PCa) bone metastasis is frequently associated with bone-forming lesions, but the source of the osteoblastic lesions remains unclear. We show that the tumor-induced bone derives partly from tumor-associated endothelial cells that have undergone endothelial-to-osteoblast (EC-to-OSB) conversion. The tumor-associated osteoblasts in PCa bone metastasis specimens and patient-derived xenografts (PDXs) were found to co-express endothelial marker Tie-2. BMP4, identified in PDX-conditioned medium, promoted EC-to-OSB conversion of 2H11 endothelial cells. BMP4 overexpression in non-osteogenic C4-2b PCa cells led to ectopic bone formation under subcutaneous implantation. Tumor-induced bone was reduced in trigenic mice (Tie2cre/Osxf/f/SCID) with endothelial-specific deletion of osteoblast cell-fate determinant OSX compared with bigenic mice (Osxf/f/SCID). Thus, tumor-induced EC-to-OSB conversion is one mechanism that leads to osteoblastic bone metastasis of PCa.


Assuntos
Neoplasias Ósseas/secundário , Diferenciação Celular , Endotélio Vascular/patologia , Osteoblastos/patologia , Neoplasias da Próstata/patologia , Animais , Biomarcadores Tumorais , Proteína Morfogenética Óssea 4/genética , Proteína Morfogenética Óssea 4/metabolismo , Neoplasias Ósseas/genética , Neoplasias Ósseas/metabolismo , Meios de Cultivo Condicionados/farmacologia , Endotélio Vascular/metabolismo , Humanos , Masculino , Camundongos , Camundongos SCID , Camundongos Transgênicos , Estadiamento de Neoplasias , Osteoblastos/metabolismo , Prognóstico , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
17.
Cell Rep ; 18(8): 1970-1981, 2017 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-28228262

RESUMO

Cell division cycle 6 (CDC6), an androgen receptor (AR) target gene, is implicated in regulating DNA replication and checkpoint mechanisms. CDC6 expression is increased during prostate cancer (PCa) progression and positively correlates with AR in PCa tissues. AR or CDC6 knockdown, together with AZD7762, a Chk1/2 inhibitor, results in decreased TopBP1-ATR-Chk1 signaling and markedly increased ataxia-telangiectasia-mutated (ATM) phosphorylation, a biomarker of DNA damage, and synergistically increases treatment efficacy. Combination treatment with the AR signaling inhibitor enzalutamide (ENZ) and the Chk1/2 inhibitor AZD7762 demonstrates synergy with regard to inhibition of AR-CDC6-ATR-Chk1 signaling, ATM phosphorylation induction, and apoptosis in VCaP (mutant p53) and LNCaP-C4-2b (wild-type p53) cells. CDC6 overexpression significantly reduced ENZ- and AZD7762-induced apoptosis. Additive or synergistic therapeutic activities are demonstrated in AR-positive animal xenograft models. These findings have important clinical implications, since they introduce a therapeutic strategy for AR-positive, metastatic, castration-resistant PCa, regardless of p53 status, through targeting AR-CDC6-ATR-Chk1 signaling.


Assuntos
Antagonistas de Receptores de Andrógenos/farmacologia , Proteínas de Ciclo Celular/metabolismo , Quinase 1 do Ponto de Checagem/metabolismo , Dano ao DNA/fisiologia , Proteínas Nucleares/metabolismo , Neoplasias da Próstata/metabolismo , Receptores Androgênicos/metabolismo , Animais , Apoptose/efeitos dos fármacos , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Biomarcadores/metabolismo , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Dano ao DNA/efeitos dos fármacos , Replicação do DNA/efeitos dos fármacos , Proteínas de Ligação a DNA/metabolismo , Humanos , Masculino , Camundongos , Camundongos Nus , Fosforilação/efeitos dos fármacos , Neoplasias da Próstata/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos , Tiofenos/farmacologia , Ureia/análogos & derivados , Ureia/farmacologia
18.
Biochim Biophys Acta Gene Regul Mech ; 1860(5): 598-603, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27815195

RESUMO

The CCAAT-binding factor CBF/NF-Y is needed for cell proliferation and early embryonic development. NF-Y can regulate the expression of different cell type-specific genes that are activated by various physiological signaling pathways. Dysregulation of NF-Y was observed in pathogenic conditions in humans such as scleroderma, neurodegenerative disease, and cancer. Conditional inactivation of the NF-YA gene in mice demonstrated that NF-Y activity is essential for normal tissue homeostasis, survival, and metabolic function. Altogether, NF-Y is an essential transcription factor that plays a critical role in mammalian development, from the early stages to adulthood, and in human pathogenesis. This article is part of a Special Issue entitled: Nuclear Factor Y in Development and Disease, edited by Prof. Roberto Mantovani.


Assuntos
Fator de Ligação a CCAAT/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias Experimentais/metabolismo , Doenças Neurodegenerativas/metabolismo , Esclerodermia Difusa/metabolismo , Animais , Fator de Ligação a CCAAT/genética , Humanos , Camundongos , Proteínas de Neoplasias/genética , Neoplasias Experimentais/genética , Doenças Neurodegenerativas/genética , Esclerodermia Difusa/genética
19.
Sci Rep ; 6: 35354, 2016 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-27748439

RESUMO

Cytochrome P450 17α-hydroxylase/17,20-lyase (CYP17A1) is a validated treatment target for the treatment of metastatic castration-resistant prostate cancer (CRPC). Abiraterone acetate (AA) inhibits both 17α-hydroxylase (hydroxylase) and 17,20-lyase (lyase) reactions catalyzed by CYP17A1 and thus depletes androgen biosynthesis. However, coadministration of prednisone is required to suppress the mineralocorticoid excess and cortisol depletion that result from hydroxylase inhibition. VT-464, a nonsteroidal small molecule, selectively inhibits CYP17A1 lyase and therefore does not require prednisone supplementation. Administration of VT-464 in a metastatic CRPC patient presenting with high tumoral expression of both androgen receptor (AR) and CYP17A1, showed significant reduction in the level of both dehydroepiandrosterone (DHEA) and serum PSA. Treatment of a CRPC patient-derived xenograft, MDA-PCa-133 expressing H874Y AR mutant with VT-464, reduced the increase in tumor volume in castrate male mice more than twice as much as the vehicle (P < 0.05). Mass spectrometry analysis of post-treatment xenograft tumor tissues showed that VT-464 significantly decreased intratumoral androgens but not cortisol. VT-464 also reduced AR signaling more effectively than abiraterone in cultured PCa cells expressing T877A AR mutant. Collectively, this study suggests that VT-464 therapy can effectively treat CRPC and be used in precision medicine based on androgen receptor mutation status.


Assuntos
Naftalenos/administração & dosagem , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Receptores Androgênicos/metabolismo , Esteroide 17-alfa-Hidroxilase/antagonistas & inibidores , Triazóis/administração & dosagem , Acetato de Abiraterona/administração & dosagem , Androgênios/biossíntese , Animais , Biópsia , Linhagem Celular Tumoral , Desidroepiandrosterona/química , Humanos , Hidrocortisona/sangue , Masculino , Espectrometria de Massas , Camundongos , Camundongos SCID , Transplante de Neoplasias , Medicina de Precisão , Prednisona/administração & dosagem , Receptores Androgênicos/genética , Transdução de Sinais , Esteroide 17-alfa-Hidroxilase/metabolismo
20.
Sci Rep ; 6: 34575, 2016 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-27687130

RESUMO

The mammalian central nervous system (CNS) contains various types of neurons with different neuronal functions. In contrast to established roles of cell type-specific transcription factors on neuronal specification and maintenance, whether ubiquitous transcription factors have conserved or differential neuronal function remains uncertain. Here, we revealed that inactivation of a ubiquitous factor NF-Y in different sets of neurons resulted in cell type-specific neuropathologies and gene downregulation in mouse CNS. In striatal and cerebellar neurons, NF-Y inactivation led to ubiquitin/p62 pathologies with downregulation of an endoplasmic reticulum (ER) chaperone Grp94, as we previously observed by NF-Y deletion in cortical neurons. In contrast, NF-Y inactivation in motor neurons induced neuronal loss without obvious protein deposition. Detailed analysis clarified downregulation of another ER chaperone Grp78 in addition to Grp94 in motor neurons, and knockdown of both ER chaperones in motor neurons recapitulated the pathology observed after NF-Y inactivation. Finally, additional downregulation of Grp78 in striatal neurons suppressed ubiquitin accumulation induced by NF-Y inactivation, implying that selective ER chaperone downregulation mediates different neuropathologies. Our data suggest distinct roles of NF-Y in protein homeostasis and neuronal maintenance in the CNS by differential regulation of ER chaperone expression.

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