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1.
Opt Express ; 32(3): 3698-3709, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38297585

RESUMO

In this paper, we use the method of high order TMn1 mode selection from the concept of narrow-band Smith-Purcell radiation (SPR) for powerful, over-mode, multi-gap extended interaction circuit designs toward millimeter wave and Terahertz (THz) region. As a core part, the multiple gaps interaction structure, equivalent to a subwavelength hole array (SHA), excites the narrow band SPR when an electron beam is injected. The SPR energy is collected by a pair of closed cavities, which satisfies (n-1) standing wave units. The SPR energy in the optimized cavity allows a high index n TMn1 mode operation to achieve the strongest Ez field and high characteristic impedance in a closed multi-gap resonant circuit. This provides an effective design to establish a stable high-order TMn1 mode that supports extended interaction circuits with large cross sections. A 0.46 THz extended interaction circuit, employing the novel high order TM51-2π mode operation output structure, has been designed to demonstrate the efficient beam-wave interaction in the proposed system. The method of TMn1 mode selection provides new insight into the understanding of the high-frequency extended interaction circuits by introducing the SPR concept, benefiting the development of millimeter wave and THz vacuum electron devices (VEDs).

2.
Cell ; 133(6): 963-77, 2008 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-18555774

RESUMO

VAP proteins (human VAPB/ALS8, Drosophila VAP33, and C. elegans VPR-1) are homologous proteins with an amino-terminal major sperm protein (MSP) domain and a transmembrane domain. The MSP domain is named for its similarity to the C. elegans MSP protein, a sperm-derived hormone that binds to the Eph receptor and induces oocyte maturation. A point mutation (P56S) in the MSP domain of human VAPB is associated with Amyotrophic lateral sclerosis (ALS), but the mechanisms underlying the pathogenesis are poorly understood. Here we show that the MSP domains of VAP proteins are cleaved and secreted ligands for Eph receptors. The P58S mutation in VAP33 leads to a failure to secrete the MSP domain as well as ubiquitination, accumulation of inclusions in the endoplasmic reticulum, and an unfolded protein response. We propose that VAP MSP domains are secreted and act as diffusible hormones for Eph receptors. This work provides insight into mechanisms that may impact the pathogenesis of ALS.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Drosophila/metabolismo , Proteínas de Membrana/metabolismo , Receptores da Família Eph/metabolismo , Proteínas de Transporte Vesicular/metabolismo , Esclerose Lateral Amiotrófica/metabolismo , Animais , Animais Geneticamente Modificados , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/química , Proteínas de Caenorhabditis elegans/genética , Linhagem Celular , Proteínas de Drosophila/química , Proteínas de Drosophila/genética , Drosophila melanogaster/metabolismo , Retículo Endoplasmático/metabolismo , Humanos , Ligantes , Proteínas de Membrana/química , Proteínas de Membrana/genética , Dobramento de Proteína , Estrutura Terciária de Proteína , Ubiquitinação , Proteínas de Transporte Vesicular/química , Proteínas de Transporte Vesicular/genética
3.
Genes Chromosomes Cancer ; 60(6): 434-446, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33527590

RESUMO

Renal cell carcinoma (RCC) is not a single disease but is made up of several different histologically defined subtypes that are associated with distinct genetic alterations which require subtype specific management and treatment. Papillary renal cell carcinoma (pRCC) is the second most common subtype after conventional/clear cell RCC (ccRCC), representing ~20% of cases, and is subcategorized into type 1 and type 2 pRCC. It is important for preclinical studies to have cell lines that accurately represent each specific RCC subtype. This study characterizes seven cell lines derived from both primary and metastatic sites of type 1 pRCC, including the first cell line derived from a hereditary papillary renal carcinoma (HPRC)-associated tumor. Complete or partial gain of chromosome 7 was observed in all cell lines and other common gains of chromosomes 16, 17, or 20 were seen in several cell lines. Activating mutations of MET were present in three cell lines that all demonstrated increased MET phosphorylation in response to HGF and abrogation of MET phosphorylation in response to MET inhibitors. CDKN2A loss due to mutation or gene deletion, associated with poor outcomes in type 1 pRCC patients, was observed in all cell line models. Six cell lines formed tumor xenografts in athymic nude mice and thus provide in vivo models of type 1 pRCC. These type 1 pRCC cell lines provide a comprehensive representation of the genetic alterations associated with pRCC that will give insight into the biology of this disease and be ideal preclinical models for therapeutic studies.


Assuntos
Carcinoma de Células Renais/genética , Autenticação de Linhagem Celular/métodos , Neoplasias Renais/genética , Ensaios Antitumorais Modelo de Xenoenxerto/métodos , Animais , Carcinoma de Células Renais/patologia , Linhagem Celular Tumoral , Instabilidade Cromossômica , Inibidor p16 de Quinase Dependente de Ciclina/genética , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Humanos , Neoplasias Renais/patologia , Camundongos , Mutação , Proteínas Proto-Oncogênicas c-met/genética , Proteínas Proto-Oncogênicas c-met/metabolismo
4.
J Biol Chem ; 295(39): 13410-13418, 2020 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-32820045

RESUMO

An important context in which metabolism influences tumorigenesis is the genetic cancer syndrome hereditary leiomyomatosis and renal cell carcinoma (HLRCC), a disease in which mutation of the tricarboxylic acid cycle enzyme fumarate hydratase (FH) causes hyperaccumulation of fumarate. This electrophilic oncometabolite can alter gene activity at the level of transcription, via reversible inhibition of epigenetic dioxygenases, as well as posttranslationally, via covalent modification of cysteine residues. To better understand the potential for metabolites to influence posttranslational modifications important to tumorigenesis and cancer cell growth, here we report a chemoproteomic analysis of a kidney-derived HLRCC cell line. Using a general reactivity probe, we generated a data set of proteomic cysteine residues sensitive to the reduction in fumarate levels caused by genetic reintroduction of active FH into HLRCC cell lines. This revealed a broad up-regulation of cysteine reactivity upon FH rescue, which evidence suggests is caused by an approximately equal proportion of transcriptional and posttranslational modification-mediated regulation. Gene ontology analysis highlighted several new targets and pathways potentially modulated by FH mutation. Comparison of the new data set with prior studies highlights considerable heterogeneity in the adaptive response of cysteine-containing proteins in different models of HLRCC. This is consistent with emerging studies indicating the existence of cell- and tissue-specific cysteine-omes, further emphasizing the need for characterization of diverse models. Our analysis provides a resource for understanding the proteomic adaptation to fumarate accumulation and a foundation for future efforts to exploit this knowledge for cancer therapy.


Assuntos
Cisteína/metabolismo , Fumarato Hidratase/metabolismo , Fumaratos/metabolismo , Neoplasias Renais/metabolismo , Leiomiomatose/metabolismo , Síndromes Neoplásicas Hereditárias/metabolismo , Neoplasias Cutâneas/metabolismo , Neoplasias Uterinas/metabolismo , Linhagem Celular Tumoral , Cisteína/genética , Fumarato Hidratase/genética , Humanos , Neoplasias Renais/genética , Neoplasias Renais/patologia , Leiomiomatose/genética , Leiomiomatose/patologia , Síndromes Neoplásicas Hereditárias/genética , Síndromes Neoplásicas Hereditárias/patologia , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia , Neoplasias Uterinas/genética , Neoplasias Uterinas/patologia
5.
Genes Chromosomes Cancer ; 59(8): 472-483, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32259323

RESUMO

Renal medullary carcinoma (RMC) is a rare, aggressive disease that predominantly afflicts individuals of African or Mediterranean descent with sickle cell trait. RMC comprises 1% of all renal cell carcinoma diagnoses with a median overall survival of 13 months. Patients are typically young (median age-22) and male (male:female ratio of 2:1) and tumors are characterized by complete loss of expression of the SMARCB1 tumor suppressor protein. Due to the low incidence of RMC and the disease's aggressiveness, treatment decisions are often based on case reports. Thus, it is critical to develop preclinical models of RMC to better understand the pathogenesis of this disease and to identify effective forms of therapy. Two novel cell line models, UOK353 and UOK360, were derived from primary RMCs that both demonstrated the characteristic SMARCB1 loss. Both cell lines overexpressed EZH2 and other members of the polycomb repressive complex and EZH2 inhibition in RMC tumor spheroids resulted in decreased viability. High throughput drug screening of both cell lines revealed several additional candidate compounds, including bortezomib that had both in vitro and in vivo antitumor activity. The activity of bortezomib was shown to be partially dependent on increased oxidative stress as addition of the N-acetyl cysteine antioxidant reduced the effect on cell proliferation. Combining bortezomib and cisplatin further decreased cell viability both in vitro and in vivo that single agent bortezomib treatment. The UOK353 and UOK360 cell lines represent novel preclinical models for the development of effective forms of therapy for RMC patients.


Assuntos
Carcinoma Medular/patologia , Neoplasias Renais/patologia , Cultura Primária de Células/métodos , Ensaios Antitumorais Modelo de Xenoenxerto/métodos , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Bortezomib/farmacologia , Bortezomib/uso terapêutico , Carcinoma Medular/tratamento farmacológico , Carcinoma Medular/genética , Autenticação de Linhagem Celular/métodos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Humanos , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/genética , Camundongos , Camundongos Nus , Proteína SMARCB1/genética , Proteína SMARCB1/metabolismo , Células Tumorais Cultivadas
6.
Cancer ; 125(7): 1060-1069, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30548481

RESUMO

BACKGROUND: An inherited susceptibility to renal cancers is associated with multiple predisposing genes, but most screening tests are limited to patients with a family history. Next-generation sequencing (NGS)-based multigene panels provide an efficient and adaptable tool for investigating pathogenic germline mutations on a larger scale. This study investigated the frequency of pathogenic germline mutations in renal cancer predisposition genes in patients with sporadic, early-onset disease. METHODS: An NGS-based panel of 23 known and potential renal cancer predisposition genes was used to analyze germline mutations in 190 unrelated Chinese patients under the age of 45 years who presented with renal tumors. The detected variants were filtered for pathogenicity, and then their frequencies were calculated and correlated with clinical features. Germline variants of the fumarate hydratase (FH) and BRCA1-associated protein 1 (BAP1) genes were comprehensively analyzed because of their aggressive potential. RESULTS: In total, 18 patients (9.5%) had germline mutations in 10 genes. Twelve of these 18 patients had alterations in renal cancer predisposition genes (6.3%), and 6 patients had mutations in potential predisposition genes such as BRCA1/2. Notably, pathogenic mutation carriers had a significant family history in second-degree relatives in comparison with those without pathogenic mutations (P < .001). Variants of unknown clinical significance in FH and BAP1 demonstrated evidence of additional somatic loss in tumors. CONCLUSIONS: In patients with early-onset disease, a multigene panel identified a high pathogenic germline mutation rate in renal cancer predisposition genes. This study emphasizes the importance of screening patients with early-onset disease for mutations in cancer predisposition genes. Germline screening should be encouraged in early-onset patients to provide personalized medicine and improve patient outcomes.


Assuntos
Angiomiolipoma/genética , Povo Asiático/genética , Carcinoma de Células Renais/genética , Neoplasias Renais/genética , Adolescente , Adulto , Proteína BRCA2/genética , Inibidor p16 de Quinase Dependente de Ciclina/genética , Feminino , Fumarato Hidratase/genética , Predisposição Genética para Doença , Mutação em Linhagem Germinativa , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Análise de Sequência de DNA , Proteína 1 do Complexo Esclerose Tuberosa/genética , Proteína 2 do Complexo Esclerose Tuberosa/genética , Proteínas Supressoras de Tumor/genética , Ubiquitina Tiolesterase/genética , Adulto Jovem
7.
BMC Cancer ; 19(1): 917, 2019 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-31519159

RESUMO

BACKGROUND: Renal cell carcinomas (RCC) harboring a TFE3 gene fusion (TfRCC) represent an aggressive subset of kidney tumors. Key signaling pathways of TfRCC are unknown and preclinical in vivo data are lacking. We investigated Akt/mTOR pathway activation and the preclinical efficacy of dual mTORC1/2 versus selective mTORC1 inhibition in TfRCC. METHODS: Levels of phosphorylated Akt/mTOR pathway proteins were compared by immunoblot in TfRCC and clear cell RCC (ccRCC) cell lines. Effects of the mTORC1 inhibitor, sirolimus, and the dual mTORC1/2 inhibitor, AZD8055, on Akt/mTOR activation, cell cycle progression, cell viability and cytotoxicity were compared in TfRCC cells. TfRCC xenograft tumor growth in mice was evaluated after 3-week treatment with oral AZD8055, intraperitoneal sirolimus and respective vehicle controls. RESULTS: The Akt/mTOR pathway was activated to a similar or greater degree in TfRCC than ccRCC cell lines and persisted partly during growth factor starvation, suggesting constitutive activation. Dual mTORC1/2 inhibition with AZD8055 potently inhibited TfRCC viability (IC50 = 20-50 nM) due at least in part to cell cycle arrest, while benign renal epithelial cells were relatively resistant (IC50 = 400 nM). Maximal viability reduction was greater with AZD8055 than sirolimus (80-90% versus 30-50%), as was the extent of Akt/mTOR pathway inhibition, based on significantly greater suppression of P-Akt (Ser473), P-4EBP1, P-mTOR and HIF1α. In mouse xenograft models, AZD8055 achieved significantly better tumor growth inhibition and prolonged mouse survival compared to sirolimus or vehicle controls. CONCLUSIONS: Akt/mTOR activation is common in TfRCC and a promising therapeutic target. Dual mTORC1/2 inhibition suppresses Akt/mTOR signaling more effectively than selective mTORC1 inhibition and demonstrates in vivo preclinical efficacy against TFE3-fusion renal cell carcinoma.


Assuntos
Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Carcinoma de Células Renais/genética , Alvo Mecanístico do Complexo 1 de Rapamicina/antagonistas & inibidores , Alvo Mecanístico do Complexo 2 de Rapamicina/antagonistas & inibidores , Morfolinas/farmacologia , Animais , Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/metabolismo , Carcinoma de Células Renais/patologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Humanos , Camundongos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Genes Chromosomes Cancer ; 56(6): 484-492, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28196407

RESUMO

Hereditary leiomyomatosis and renal cell carcinoma (HLRCC) is a familial cancer syndrome associated with the development of cutaneous and uterine leiomyomas, and an aggressive form of type 2 papillary kidney cancer. HLRCC is characterized by germline mutation of the FH gene. This study evaluated the prevalence and clinical phenotype of FH deletions in HLRCC patients. Patients with phenotypic manifestations consistent with HLRCC who lacked detectable germline FH intragenic mutations were investigated for FH deletion. A series of 28 patients from 13 families were evaluated using a combination of a comparative genomic hybridization (CGH) array and/or CLIA-approved FH deletion/duplication analyses. Thirteen distinct germline deletions were identified in the 13 UOB families, including 11 complete FH gene deletions and 2 partial FH gene deletions. The size of eight evaluated complete FH deletions varied from ∼4.74 Mb to 249 kb, with all deletions resulting in additional gene losses. Two partial FH gene deletions were identified, with one resulting in loss of exon 1 and the upstream region of the FH gene only. Kidney cancer was diagnosed in 9 (32%) of 28 patients and 7 (54%) of 13 families possessing either complete or partial FH deletions. Cutaneous and uterine leiomyomas were observed at similar rates to those in FH point mutation families. Complete or partial FH gene alterations in HLRCC families are associated with all of the canonical HLRCC manifestations, including type 2 papillary kidney cancer and should be screened for in any patient at-risk for this disorder.


Assuntos
Carcinoma de Células Renais/genética , Fumarato Hidratase/genética , Deleção de Genes , Genoma , Mutação em Linhagem Germinativa , Neoplasias Renais/genética , Leiomiomatose/genética , Fenótipo , Feminino , Humanos , Hibridização in Situ Fluorescente , Masculino , Linhagem
9.
Genes Chromosomes Cancer ; 56(10): 719-729, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28736828

RESUMO

Chromophobe renal cell carcinoma (ChRCC) represents 5% of all RCC cases and frequently demonstrates multiple chromosomal losses and an indolent pattern of local growth, but can demonstrate aggressive features and resistance to treatment in a metastatic setting. Cell line models are an important tool for the investigation of tumor biology and therapeutic drug efficacy. Currently, there are few ChRCC-derived cell lines and none is well characterized. This study characterizes a novel ChRCC-derived cell line model, UOK276. A large ChRCC tumor with regions of sarcomatoid differentiation was used to establish a spontaneously immortal cell line, UOK276. UOK276 was evaluated for chromosomal, mutational, and metabolic aberrations. The UOK276 cell line is hyperdiploid with a modal number of 49 chromosomes per cell, and evidence of copy-neutral loss of heterozygosity, as opposed to the classic pattern of ChRCC chromosomal losses. UOK276 demonstrated a TP53 missense mutation, expressed mutant TP53 protein, and responded to treatment with a small-molecule therapeutic agent, NSC319726, designed to reactivate mutated TP53. Xenograft tumors grew in nude mice and provide an in vivo animal model for the investigation of potential therapeutic regimes. The xenograft pathology and genetic analysis suggested that UOK276 was derived from the sarcomatoid region of the original tumor. In summary, UOK276 represents a novel in vitro and in vivo cell line model for aggressive, sarcomatoid-differentiated, TP53 mutant ChRCC. This preclinical model system could be used to investigate the novel biology of aggressive, sarcomatoid ChRCC and evaluate the new therapeutic regimes.


Assuntos
Carcinoma de Células Renais/genética , Cariótipo , Neoplasias Renais/genética , Proteína Supressora de Tumor p53/metabolismo , Animais , Carcinoma de Células Renais/metabolismo , Carcinoma de Células Renais/patologia , Linhagem Celular Tumoral , Humanos , Neoplasias Renais/metabolismo , Neoplasias Renais/patologia , Masculino , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Mutação de Sentido Incorreto , Proteína Supressora de Tumor p53/genética
10.
Nature ; 481(7381): 385-8, 2011 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-22101431

RESUMO

Mitochondrial metabolism provides precursors to build macromolecules in growing cancer cells. In normally functioning tumour cell mitochondria, oxidative metabolism of glucose- and glutamine-derived carbon produces citrate and acetyl-coenzyme A for lipid synthesis, which is required for tumorigenesis. Yet some tumours harbour mutations in the citric acid cycle (CAC) or electron transport chain (ETC) that disable normal oxidative mitochondrial function, and it is unknown how cells from such tumours generate precursors for macromolecular synthesis. Here we show that tumour cells with defective mitochondria use glutamine-dependent reductive carboxylation rather than oxidative metabolism as the major pathway of citrate formation. This pathway uses mitochondrial and cytosolic isoforms of NADP(+)/NADPH-dependent isocitrate dehydrogenase, and subsequent metabolism of glutamine-derived citrate provides both the acetyl-coenzyme A for lipid synthesis and the four-carbon intermediates needed to produce the remaining CAC metabolites and related macromolecular precursors. This reductive, glutamine-dependent pathway is the dominant mode of metabolism in rapidly growing malignant cells containing mutations in complex I or complex III of the ETC, in patient-derived renal carcinoma cells with mutations in fumarate hydratase, and in cells with normal mitochondria subjected to acute pharmacological ETC inhibition. Our findings reveal the novel induction of a versatile glutamine-dependent pathway that reverses many of the reactions of the canonical CAC, supports tumour cell growth, and explains how cells generate pools of CAC intermediates in the face of impaired mitochondrial metabolism.


Assuntos
Mitocôndrias/metabolismo , Mitocôndrias/patologia , Neoplasias/metabolismo , Neoplasias/patologia , Acetilcoenzima A/metabolismo , Animais , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/metabolismo , Carcinoma de Células Renais/patologia , Hipóxia Celular , Linhagem Celular Tumoral , Ácido Cítrico/metabolismo , Transporte de Elétrons , Complexo I de Transporte de Elétrons/metabolismo , Complexo III da Cadeia de Transporte de Elétrons/metabolismo , Fumarato Hidratase/genética , Fumarato Hidratase/metabolismo , Glucose/metabolismo , Glutamina/metabolismo , Humanos , Isocitrato Desidrogenase/metabolismo , Neoplasias Renais/genética , Neoplasias Renais/metabolismo , Neoplasias Renais/patologia , Camundongos , NADP/metabolismo
11.
J Am Chem Soc ; 138(49): 15813-15816, 2016 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-27960310

RESUMO

Dysregulated metabolism is a hallmark of many diseases, including cancer. Methods to fluorescently detect metabolites have the potential to enable new approaches to cancer detection and imaging. However, fluorescent sensing methods for naturally occurring cellular metabolites are relatively unexplored. Here we report the development of a chemical approach to detect the oncometabolite fumarate. Our strategy exploits a known bioorthogonal reaction, the 1,3-dipolar cycloaddition of nitrileimines and electron-poor olefins, to detect fumarate via fluorescent pyrazoline cycloadduct formation. We demonstrate hydrazonyl chlorides serve as readily accessible nitrileimine precursors, whose reactivity and spectral properties can be tuned to enable detection of fumarate and other dipolarophile metabolites. Finally, we show this reaction can be used to detect enzyme activity changes caused by mutations in fumarate hydratase, which underlie the familial cancer predisposition syndrome hereditary leiomyomatosis and renal cell cancer. Our studies define a novel intersection of bioorthogonal chemistry and metabolite reactivity that may be harnessed to enable biological profiling, imaging, and diagnostic applications.


Assuntos
Alcenos/metabolismo , Carcinoma de Células Renais/metabolismo , Fumarato Hidratase/metabolismo , Fumaratos/metabolismo , Iminas/metabolismo , Neoplasias Renais/metabolismo , Alcenos/química , Carcinoma de Células Renais/patologia , Fumaratos/análise , Humanos , Iminas/química , Neoplasias Renais/patologia , Estrutura Molecular
12.
Hepatology ; 62(4): 1122-31, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26058814

RESUMO

UNLABELLED: The cell fate determinant Numb is aberrantly expressed in cancer. Numb is alternatively spliced, with one isoform containing a long proline-rich region (PRR(L) ) compared to the other with a short PRR (PRR(S) ). Recently, PRR(L) was reported to enhance proliferation of breast and lung cancer cells. However, the importance of Numb alternative splicing in hepatocellular carcinoma (HCC) remains unexplored. We report here that Numb PRR(L) expression is increased in HCC and associated with early recurrence and reduced overall survival after surgery. In a panel of HCC cell lines, PRR(L) generally promotes and PRR(S) suppresses proliferation, migration, invasion, and colony formation. Knockdown of PRR(S) leads to increased Akt phosphorylation and c-Myc expression, and Akt inhibition or c-Myc silencing dampens the proliferative impact of Numb PRR(S) knockdown. In the cell models explored in this study, alternative splicing of Numb PRR isoforms is coordinately regulated by the splicing factor RNA-binding Fox domain containing 2 (RbFox2) and the kinase serine/arginine protein-specific kinase 2 (SRPK2). Knockdown of the former causes accumulation of PRR(L) , while SRPK2 knockdown causes accumulation of PRR(S) . The subcellular location of SRPK2 is regulated by the molecular chaperone heat shock protein 90, and heat shock protein 90 inhibition or knockdown phenocopies SRPK2 knockdown in promoting accumulation of Numb PRR(S) . Finally, HCC cell lines that predominantly express PRR(L) are differentially sensitive to heat shock protein 90 inhibition. CONCLUSION: Alternative splicing of Numb may provide a useful prognostic biomarker in HCC and is pharmacologically tractable.


Assuntos
Processamento Alternativo , Carcinoma Hepatocelular/genética , Diferenciação Celular/genética , Neoplasias Hepáticas/genética , Proteínas de Membrana/genética , Proteínas do Tecido Nervoso/genética , Humanos , Células Tumorais Cultivadas
13.
Am J Pathol ; 182(5): 1572-84, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23499373

RESUMO

Idiopathic pulmonary fibrosis (IPF) is a progressive fibrotic lung disease whose underlying molecular mechanisms are largely unknown. Herein, we show that focal adhesion kinase-related nonkinase (FRNK) plays a key role in limiting the development of lung fibrosis. Loss of FRNK function in vivo leads to increased lung fibrosis in an experimental mouse model. The increase in lung fibrosis is confirmed at the histological, biochemical, and physiological levels. Concordantly, loss of FRNK function results in increased fibroblast migration and myofibroblast differentiation and activation of signaling proteins that drive these phenotypes. FRNK-deficient murine lung fibroblasts also have an increased capacity to produce and contract matrix proteins. Restoration of FRNK expression in vivo and in vitro reverses these profibrotic phenotypes. These data demonstrate the multiple antifibrotic actions of FRNK. More important, FRNK expression is down-regulated in human IPF, and down-regulation of FRNK in normal human lung fibroblasts recapitulates the profibrotic phenotype seen in FRNK-deficient cells. The effect of loss and gain of FRNK in the experimental model, when taken together with its down-regulation in human IPF, suggests that FRNK acts as an endogenous negative regulator of lung fibrosis by repressing multiple profibrotic responses.


Assuntos
Proteínas Tirosina Quinases/metabolismo , Fibrose Pulmonar/enzimologia , Fibrose Pulmonar/patologia , Adulto , Animais , Bleomicina , Diferenciação Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Quinase 1 de Adesão Focal/metabolismo , Humanos , Pulmão/efeitos dos fármacos , Pulmão/enzimologia , Pulmão/patologia , Camundongos , Camundongos Endogâmicos C57BL , Miofibroblastos/efeitos dos fármacos , Miofibroblastos/enzimologia , Miofibroblastos/patologia , Proteínas Tirosina Quinases/deficiência , Transdução de Sinais/efeitos dos fármacos , Fator de Crescimento Transformador beta1/farmacologia
14.
Micromachines (Basel) ; 15(6)2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38930693

RESUMO

Surface plasmon polaritons (SPPs) have become a research hotspot due to their high intensity and subwavelength localization. Through free-electron excitation, a portion of the momentum of moving electrons can be converted into SPPs. Converting highly localized SPPs into a radiated field is an approach with the potential to aid in the development of a light radiation source. Reducing losses of SPPs is currently a critical challenge that needs to be addressed. The lifetime of SPPs in metal films is longer than that in metal blocks. Traditional optical gratings can transform SPPs into radiation to avoid the decay of SPPs in metal; however, they are created by etching metal films, so they tend to alter the dispersion characteristics of these films and will emit radiation in the direction perpendicular to the metal surface. This paper proposes an approach to converting the SPPs of a metal film excited by free electrons into a radiation field via lateral grating and obtaining in-plane radiation. We investigate the properties of SPP lateral radiation. The study of lateral radiation from metal films holds significant importance for SPP radiation sources and SPP on-chip circuit development.

15.
Redox Biol ; 63: 102720, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37230005

RESUMO

Vascular calcification is accelerated in patients with diabetes mellitus and increases risk of cardiovascular events and mortality. Vascular smooth muscle cells (VSMC) play a key role in regulating vascular tone and contribute significantly to the development of diabetic vasculopathy. In this study, the function of stromal interaction molecule 1 (STIM1), an important regulator for intracellular calcium homeostasis, in diabetic vascular calcification was investigated, and the underlying molecular mechanisms were uncovered. A SMC-specific STIM1 deletion mouse model (STIM1Δ/Δ) was generated by breeding the STIM1 floxed mice (STIM1f/f) with SM22α-Cre transgenic mice. Using aortic arteries from the STIM1Δ/Δ mice and their STIM1f/f littermates, we found that SMC-specific STIM1 deletion induced calcification of aortic arteries cultured in osteogenic media ex vivo. Furthermore, STIM1 deficiency promoted osteogenic differentiation and calcification of VSMC from the STIM1Δ/Δ mice. In the low-dose streptozotocin (STZ)-induced mouse model of diabetes, SMC-specific STIM1 deletion markedly enhanced STZ-induced vascular calcification and stiffness in the STIM1Δ/Δ mice. The diabetic mice with SMC-specific STIM1 ablation also exhibited increased aortic expression of the key osteogenic transcription factor, Runx2, and protein O-GlcNAcylation, an important post-translational modulation that we have reported to promote vascular calcification and stiffness in diabetes. Consistently, elevation of O-GlcNAcylation was demonstrated in aortic arteries and VSMC from the STIM1Δ/Δ mice. Inhibition of O-GlcNAcylation with a pharmacological inhibitor abolished STIM1 deficiency-induced VSMC calcification, supporting a critical role of O-GlcNAcylation in mediating STIM1 deficiency-induced VSMC calcification. Mechanistically, we identified that STIM1 deficiency resulted in impaired calcium homeostasis, which activated calcium signaling and increased endoplasmic reticulum (ER) stress in VSMC, while inhibition of ER stress attenuated STIM1-induced elevation of protein O-GlcNAcylation. In conclusion, the study has demonstrated a causative role of SMC-expressed STIM1 in regulating vascular calcification and stiffness in diabetes. We have further identified a novel mechanisms underlying STIM1 deficiency-induced impairment of calcium homeostasis and ER stress in upregulation of protein O-GlcNAcylation in VSMC, which promotes VSMC osteogenic differentiation and calcification in diabetes.


Assuntos
Diabetes Mellitus Experimental , Calcificação Vascular , Camundongos , Animais , Cálcio/metabolismo , Diabetes Mellitus Experimental/metabolismo , Osteogênese , Células Cultivadas , Calcificação Vascular/etiologia , Camundongos Transgênicos , Modelos Animais de Doenças , Homeostase , Miócitos de Músculo Liso/metabolismo
16.
J Gerontol A Biol Sci Med Sci ; 78(2): 223-226, 2023 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-36124974

RESUMO

Age-related declines in physical and cognitive function can have tremendous, negative impacts on health span and quality of life. Therefore, we investigated the potential of utilizing a probiotic treatment to target the renin-angiotensin system (RAS) in conjunction with moderate exercise to ameliorate age-related declines in cognitive and physical function in aged rats. Herein we utilized a genetically modified angiotensin (1-7), which activates a "complementary" arm of the RAS through binding Mas (AT7) receptors. This process induces several beneficial physiologic effects, including decreased inflammation and enhanced physical/cognitive function. Thus, in this short research report, we suggest the efficacy of this Ang(1-7) releasing Lactobacillus paracasei (LPA) as either an alternative strategy to exercise, or more likely as an adjuvant to moderate exercise, for the prevention of both physical and cognitive decline especially in female rats.


Assuntos
Angiotensina II , Qualidade de Vida , Feminino , Ratos , Animais , Sistema Renina-Angiotensina/fisiologia , Angiotensina I , Fragmentos de Peptídeos
17.
J Appl Physiol (1985) ; 134(5): 1135-1153, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36892893

RESUMO

Angiotensin (1-7) [Ang (1-7)] is an active heptapeptide of the noncanonical arm of the renin-angiotensin system that modulates molecular signaling pathways associated with vascular and cellular inflammation, vasoconstriction, and fibrosis. Preclinical evidence suggests that Ang (1-7) is a promising therapeutic target that may ameliorate physical and cognitive function in late life. However, treatment pharmacodynamics limits its clinical applicability. Therefore, this study explored the underlying mechanisms altered by a genetically modified probiotic (GMP) that expresses Ang (1-7) combined with and without exercise training in an aging male rat model as a potential adjunct strategy to exercise training to counteract the decline of physical and cognitive function. We evaluated cross-tissue (prefrontal cortex, hippocampus, colon, liver, and skeletal muscle) multi-omics responses. After 12 wk of intervention, the 16S mRNA microbiome analysis revealed a main effect of probiotic treatment within- and between groups. The probiotic treatment enhanced α diversity (Inverse Simpson (F[2,56] = 4.44; P = 0.02); Shannon-Wiener (F[2,56] = 4.27; P = 0.02)) and ß-diversity (F[2,56] = 2.66; P = 0.01) among rats receiving our GMP. The analysis of microbes' composition revealed three genera altered by our GMP (Enterorhabdus, Muribaculaceae unclassified, and Faecalitalea). The mRNA multi-tissue data analysis showed that our combined intervention upregulated neuroremodeling pathways on prefrontal cortex (i.e., 140 genes), inflammation gene expression in the liver (i.e., 63 genes), and circadian rhythm signaling on skeletal muscle. Finally, the integrative network analysis detected different communities of tightly (|r| > 0.8 and P < 0.05) correlated metabolites, genera, and genes in these tissues.NEW & NOTEWORTHY This manuscript uses a multiomics approach (i.e., microbiome, metabolomics, and transcriptomics) to explore the underlying mechanisms driven by a genetically modified probiotic (GMP) designed to express angiotensin (1-7) combined with moderate exercise training in an aged male rat model. After 12 wk of intervention, our findings suggest that our GMP enhanced gut microbial diversity while exercise training altered the transcriptional response in relevant neuroremodeling genes, inflammation, and circadian rhythm signaling pathways in an aging animal model.


Assuntos
Multiômica , Condicionamento Físico Animal , Ratos , Animais , Masculino , Condicionamento Físico Animal/fisiologia , Sistema Renina-Angiotensina/fisiologia , Inflamação
18.
J Exp Clin Cancer Res ; 42(1): 99, 2023 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-37095531

RESUMO

BACKGROUND: MiT-Renal Cell Carcinoma (RCC) is characterized by genomic translocations involving microphthalmia-associated transcription factor (MiT) family members TFE3, TFEB, or MITF. MiT-RCC represents a specific subtype of sporadic RCC that is predominantly seen in young patients and can present with heterogeneous histological features making diagnosis challenging. Moreover, the disease biology of this aggressive cancer is poorly understood and there is no accepted standard of care therapy for patients with advanced disease. Tumor-derived cell lines have been established from human TFE3-RCC providing useful models for preclinical studies. METHODS: TFE3-RCC tumor derived cell lines and their tissues of origin were characterized by IHC and gene expression analyses. An unbiased high-throughput drug screen was performed to identify novel therapeutic agents for treatment of MiT-RCC. Potential therapeutic candidates were validated in in vitro and in vivo preclinical studies. Mechanistic assays were conducted to confirm the on-target effects of drugs. RESULTS: The results of a high-throughput small molecule drug screen utilizing three TFE3-RCC tumor-derived cell lines identified five classes of agents with potential pharmacological efficacy, including inhibitors of phosphoinositide-3-kinase (PI3K) and mechanistic target of rapamycin (mTOR), and several additional agents, including the transcription inhibitor Mithramycin A. Upregulation of the cell surface marker GPNMB, a specific MiT transcriptional target, was confirmed in TFE3-RCC and evaluated as a therapeutic target using the GPNMB-targeted antibody-drug conjugate CDX-011. In vitro and in vivo preclinical studies demonstrated efficacy of the PI3K/mTOR inhibitor NVP-BGT226, Mithramycin A, and CDX-011 as potential therapeutic options for treating advanced MiT-RCC as single agents or in combination. CONCLUSIONS: The results of the high-throughput drug screen and validation studies in TFE3-RCC tumor-derived cell lines have provided in vitro and in vivo preclinical data supporting the efficacy of the PI3K/mTOR inhibitor NVP-BGT226, the transcription inhibitor Mithramycin A, and GPNMB-targeted antibody-drug conjugate CDX-011 as potential therapeutic options for treating advanced MiT-RCC. The findings presented here should provide the basis for designing future clinical trials for patients with MiT-driven RCC.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Humanos , Carcinoma de Células Renais/patologia , Neoplasias Renais/patologia , Inibidores de MTOR , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Translocação Genética , Fosfatidilinositol 3-Quinase , Glicoproteínas de Membrana/genética
19.
Biochim Biophys Acta ; 1812(4): 565-71, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21094253

RESUMO

Recent studies recognize that Hypocretin system (also known as Orexin) plays a critical role in sleep/wake disorders and feeding behaviors. However, little is known about the regulation of the Hypocretin system. It is also known that tumor necrosis factor alpha (TNF-α) is involved in the regulation of sleep/wake cycle. Here, we test our hypothesis that the Hypocretin system is regulated by TNF-α. Prepro-Hypocretin and Hypocretin receptor 2 (HcrtR2) can be detected at a very low level in rat B35 neuroblastoma cells. In response to TNF-α, Prepro-Hypocretin mRNA and protein levels are down-regulated, and also HcrtR2 protein level is down-regulated in B35 cells. To investigate the mechanism, exogenous rat Prepro-Hypocretin and rat HcrtR2 were overexpressed in B35 cells. In response to TNF-α, protein and mRNA of Prepro-Hypocretin are significantly decreased (by 93% and 94%, respectively), and the half-life of Prepro-Hypocretin mRNA is decreased in a time- and dose-dependent manner. The level of HcrtR2 mRNA level is not affected by TNF-α treatment; however, HcrtR2 protein level is significantly decreased (by 86%) through ubiquitination in B35 cells treated with TNF-α. Downregulation of cellular inhibitor of apoptosis protein-1 and -2 (cIAP-1 and -2) abrogates the HcrtR2 ubiquitination induced by TNF-α. The control green fluorescent protein (GFP) expression is not affected by TNF-α treatment. These studies demonstrate that TNF-α can impair the function of the Hypocretin system by reducing the levels of both Prepro-Hypocretin and HcrtR2.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neuropeptídeos/metabolismo , Estabilidade de RNA , Receptores Acoplados a Proteínas G/metabolismo , Receptores de Neuropeptídeos/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Ubiquitinação , Animais , Linhagem Celular Tumoral , Regulação para Baixo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Neuropeptídeos/genética , Receptores de Orexina , Orexinas , RNA Mensageiro/genética , Ratos , Receptores Acoplados a Proteínas G/genética , Receptores de Neuropeptídeos/genética , Transtornos do Sono-Vigília/etiologia
20.
J Urol ; 188(6): 2063-71, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23083876

RESUMO

PURPOSE: Recently, a new renal cell cancer syndrome has been linked to germline mutation of multiple subunits (SDHB/C/D) of the Krebs cycle enzyme, succinate dehydrogenase. We report our experience with the diagnosis, evaluation and treatment of this novel form of hereditary kidney cancer. MATERIALS AND METHODS: Patients with suspected hereditary kidney cancer were enrolled on a National Cancer Institute institutional review board approved protocol to study inherited forms of kidney cancer. Individuals from families with germline SDHB, SDHC and SDHD mutations, and kidney cancer underwent comprehensive clinical and genetic evaluation. RESULTS: A total of 14 patients from 12 SDHB mutation families were evaluated. Patients presented with renal cell cancer at an early age (33 years, range 15 to 62), metastatic kidney cancer developed in 4 and some families had no manifestation other than kidney tumors. An additional family with 6 individuals found to have clear cell renal cell cancer that presented at a young average age (47 years, range 40 to 53) was identified with a germline SDHC mutation (R133X) Metastatic disease developed in 2 of these family members. A patient with a history of carotid body paragangliomas and an aggressive form of kidney cancer was evaluated from a family with a germline SDHD mutation. CONCLUSIONS: SDH mutation associated renal cell carcinoma can be an aggressive type of kidney cancer, especially in younger individuals. Although detection and management of early tumors is most often associated with a good outcome, based on our initial experience with these patients and our long-term experience with hereditary leiomyomatosis and renal cell carcinoma, we recommend careful surveillance of patients at risk for SDH mutation associated renal cell carcinoma and wide surgical excision of renal tumors.


Assuntos
Carcinoma de Células Renais/genética , Mutação em Linhagem Germinativa , Neoplasias Renais/genética , Succinato Desidrogenase/genética , Adolescente , Adulto , Carcinoma de Células Renais/diagnóstico , Carcinoma de Células Renais/cirurgia , Progressão da Doença , Feminino , Doenças Genéticas Inatas/diagnóstico , Doenças Genéticas Inatas/genética , Doenças Genéticas Inatas/cirurgia , Testes Genéticos , Humanos , Neoplasias Renais/diagnóstico , Neoplasias Renais/cirurgia , Masculino , Pessoa de Meia-Idade , Linhagem , Adulto Jovem
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