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1.
J Neurol Neurosurg Psychiatry ; 91(8): 846-848, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32354770

RESUMO

BACKGROUND: Emergence of the novel corona virus (severe acute respiratory syndrome (SARS)-CoV-2) in December 2019 has led to the COVID-19 pandemic. The extent of COVID-19 involvement in the central nervous system is not well established, and the presence or the absence of SARS-CoV-2 particles in the cerebrospinal fluid (CSF) is a topic of debate. CASE DESCRIPTION: We present two patients with COVID-19 and concurrent neurological symptoms. Our first patient is a 31-year-old man who had flu-like symptoms due to COVID-19 and later developed an acute-onset severe headache and loss of consciousness and was diagnosed with a Hunt and Hess grade 3 subarachnoid haemorrhage from a ruptured aneurysm. Our second patient is a 62-year-old woman who had an ischaemic stroke with massive haemorrhagic conversion requiring a decompressive hemicraniectomy. Both patients' CSF was repeatedly negative on real-time PCR analysis despite concurrent neurological disease. CONCLUSION: Our report shows that patients' CSF may be devoid of viral particles even when they test positive for COVID-19 on a nasal swab. Whether SARS-CoV-2 is present in CSF may depend on the systemic disease severity and the degree of the virus' nervous tissue tropism and should be examined in future studies.


Assuntos
Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/líquido cefalorraquidiano , Infecções por Coronavirus/complicações , Pneumonia Viral/líquido cefalorraquidiano , Pneumonia Viral/complicações , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/virologia , Adulto , COVID-19 , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , SARS-CoV-2 , Acidente Vascular Cerebral/líquido cefalorraquidiano
2.
J Biol Chem ; 293(31): 12137-12148, 2018 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-29921586

RESUMO

Regulation of autophagy by proteolytically cleaved fragments of heparan sulfate proteoglycans is a novel and current research focus in tumor biology. Endorepellin is the C-terminal angiostatic fragment of the heparan sulfate proteoglycan perlecan and induces autophagy in endothelial cells. To further investigate this property, we used NanoString, a digital PCR platform for measuring pre-defined transcripts in biological samples to analyze a custom subset of 95 autophagy-related genes in human umbilical vein endothelial cells treated with ultrapure human recombinant endorepellin. We discovered an endorepellin-evoked pro-autophagic and pro-mitophagic gene expression signatures, which included two coordinately up-regulated mitochondrial-associated genes encoding the E3 ubiquitin protein ligase Parkin and the tumor suppressor mitostatin. Induction of both proteins required the tyrosine kinase activity of vascular endothelial growth factor receptor 2 (VEGFR2). Furthermore, we discovered that endorepellin evoked mitochondrial depolarization in endothelial cells via a specific interaction between its two proximal LG1/2 domains and VEGFR2. We also found that following loss of membrane potential, mitostatin and parkin interact and that mitostatin associates with the established Parkin receptor mitofusin-2. In conclusion, we have identified a critical role for endorepellin in remodeling the autophagic transcriptome and influencing mitochondrial homeostasis.


Assuntos
Autofagia , Proteoglicanas de Heparan Sulfato/metabolismo , Células Endoteliais da Veia Umbilical Humana/citologia , Mitofagia , Fragmentos de Peptídeos/metabolismo , Proteínas de Transporte , GTP Fosfo-Hidrolases/genética , GTP Fosfo-Hidrolases/metabolismo , Proteoglicanas de Heparan Sulfato/genética , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Fragmentos de Peptídeos/genética , Ligação Proteica , Transdução de Sinais , Transcriptoma , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genética , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo
3.
Toxicol Appl Pharmacol ; 378: 114606, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31170415

RESUMO

Inorganic arsenic is an environmental carcinogen that poses a major global public health risk. A high percentage of drinking water from wells in the U.S. contains higher-than-normal levels of arsenic, suggesting an increased risk of arsenic-induced deleterious effects. In addition to primary preventive measures, therapeutic strategies need to effectively address and integrate multiple molecular mechanisms underlying arsenic-induced carcinogenesis. We previously showed that the loss of miR-199a-5p in arsenic-transformed cells is pivotal to promote arsenic-induced angiogenesis and tumor growth in lung epithelial cells. In this study, we further showed that subacute or chronic exposure to arsenic diminished miR-199a-5p levels largely due to DNA methylation, which was achieved by increased DNA methyltransferase-1 (DNMT1) activity, mediated by the formation of specific protein 1 (Sp1)/DNMT1 complex. In addition to the DNA hypermethylation, arsenic exposure also repressed miR-199a transcription through a transcriptional repressor Sp1. We further identified an association between miR-199a-5p repression and the arsenic-mediated energy metabolic shift, as reflected by mitochondria defects and a switch to glycolysis, in which a glycolytic enzyme pyruvate kinase 2 (PKM2) was a functional target of miR-199a-5p. Taken together, the repression of miR-199a-5p through both Sp1-dependent DNA methylation and Sp1 transcriptional repression promotes an arsenic-mediated metabolic shift from mitochondria respiration to aerobic glycolysis via PKM2.


Assuntos
Arsênio/efeitos adversos , Metilação de DNA/efeitos dos fármacos , MicroRNAs/genética , Fator de Transcrição Sp1/genética , Ativação Metabólica/efeitos dos fármacos , Carcinogênese/efeitos dos fármacos , Linhagem Celular , Glicólise/efeitos dos fármacos , Humanos
4.
BMC Cancer ; 16(1): 766, 2016 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-27716119

RESUMO

BACKGROUND: We sought to assess physician interest in molecular prognosic testing for patients with early stage colon cancer, and identify factors associated with the likelihood of test adoption. METHODS: We identified physicians who care for patients with early-stage (pN0) colon cancer patients, mailed them a survey, and analyzed survey responses to assess clinician receptivity to the use of a new molecular test (GUCY2C) that identifies patients at risk for recurrence, and clinician readiness to act on abnormal test results. RESULTS: Of 104 eligible potential respondents, 41 completed and returned the survey. Among responding physicians, 56 % were receptive to using the new prognostic test. Multivariable analyses showed that physicians in academic medical centers were significantly more receptive to molecular test use than those in non-academic settings. Forty-one percent of respondents were ready to act on abnormal molecular test results. Physicians who viewed current staging methods as inaccurate and were confident in their capacity to incorporate molecular testing in practice were more likely to say they would act on abnormal test results. CONCLUSIONS: Physician receptivity to molecular diagnostic testing for early-stage colon cancer patients is likely to be influenced by practice setting and perceptions related to delivering quality care to patients. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01972737.


Assuntos
Neoplasias do Colo/diagnóstico , Técnicas de Diagnóstico Molecular , Padrões de Prática Médica , Feminino , Pesquisas sobre Atenção à Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/diagnóstico , Recidiva Local de Neoplasia/prevenção & controle , Estadiamento de Neoplasias , Prognóstico , Medição de Risco , Fatores de Risco
5.
J Clin Lab Anal ; 29(6): 462-8, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25132285

RESUMO

BACKGROUND: Atypical lipomatous tumor/well-differentiated liposarcoma (ALT-WDLPS) and dedifferentiated liposarcoma (DDLPS) are characterized cytogenetically by a 12q13-15 amplification involving the mouse double minute 2 (MDM2) oncogene. Fluorescence in situ hybridization (FISH) is used frequently to detect this amplification and aid with the diagnosis of these entities, which is difficult by morphology alone. Recently, bright-field in situ hybridization techniques such as chromogenic in situ hybridization (CISH) have been introduced for the determination of MDM2 amplification status. METHODS: The present study compared the results of FISH and CISH for detecting MDM2 amplification in 41 cases of adipocytic tumors. Amplification was defined in both techniques as a MDM2/CEN12 ratio of 2 or greater. RESULTS: Eleven cases showed amplification with both FISH and CISH, and 26 cases showed no amplification with both methods. Two cases had discordant results between CISH and FISH, and two cases were not interpretable by CISH. CONCLUSION: CISH is advantageous for allowing pathologists to evaluate the histologic and molecular alterations occurring simultaneously in a specimen. Moreover, CISH is found to be more cost- and time-efficient when used with automation, and the signals do not quench over time. CISH technique is a reliable alternative to FISH in the evaluation of adipocytic tumors for MDM2 amplification.


Assuntos
Adipócitos/patologia , Biomarcadores Tumorais/genética , Amplificação de Genes , Hibridização In Situ/classificação , Hibridização In Situ/métodos , Proteínas Proto-Oncogênicas c-mdm2/genética , Neoplasias de Tecidos Moles/genética , Adipócitos/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Estudos de Casos e Controles , Feminino , Seguimentos , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Neoplasias de Tecidos Moles/patologia
6.
Behav Genet ; 44(5): 498-515, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24997773

RESUMO

Atypical Chemokine Receptor 1 (ACKR1), previously known as Duffy Antigen Receptor for Chemokines, stands out among chemokine receptors for high selective expression on cerebellar Purkinje neurons. Although ACKR1 ligands activate Purkinje cells in vitro, evidence for ACKR1 regulation of brain function in vivo is lacking. Here we demonstrate that Ackr1 (-/-) mice have markedly impaired balance and ataxia on a rotating rod and increased tremor when injected with harmaline, which induces whole-body tremor by activating Purkinje cells. Ackr1 (-/-) mice also exhibited impaired exploratory behavior, increased anxiety-like behavior and frequent episodes of marked hypoactivity under low-stress conditions. Surprisingly, Ackr1 (+/-) had similar behavioral abnormalities, indicating pronounced haploinsufficiency. The behavioral phenotype of Ackr1 (-/-) mice was the opposite of mouse models of cerebellar degeneration, and the defects persisted when Ackr1 was deficient only on non-hematopoietic cells. Together, the results suggest that normal motor function and behavior may partly depend on negative regulation of Purkinje cell activity by Ackr1.


Assuntos
Sistema do Grupo Sanguíneo Duffy , Atividade Motora , Células de Purkinje , Receptores de Superfície Celular , Animais , Feminino , Masculino , Camundongos , Sistema do Grupo Sanguíneo Duffy/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Atividade Motora/fisiologia , Células de Purkinje/metabolismo , Receptores de Superfície Celular/metabolismo
7.
Arch Pathol Lab Med ; 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38452805

RESUMO

CONTEXT.­: Mutant KRAS is the main oncogenic driver in pancreatic ductal adenocarcinomas (PDACs). However, the clinical and phenotypic implications of harboring different mutant KRAS alleles remain poorly understood. OBJECTIVE.­: To characterize the potential morphologic and clinical outcome differences in PDACs harboring distinct mutant KRAS alleles. DESIGN.­: Cohort 1 consisted of 127 primary conventional PDACs with no neoadjuvant therapy, excluding colloid/mucinous, adenosquamous, undifferentiated, and intraductal papillary mucinous neoplasm-associated carcinomas, for which an in-house 42-gene mutational panel had been performed. A morphologic classification system was devised wherein each tumor was assigned as conventional, papillary/large duct (P+LD, defined as neoplastic glands with papillary structure and/or with length ≥0.5 mm), or poorly differentiated (when the aforementioned component was 60% or more of the tumor). Cohort 2 was a cohort of 88 PDACs in The Cancer Genome Atlas, which were similarly analyzed. RESULTS.­: In both cohorts, there was significant enrichment of P+LD morphology in PDACs with KRAS G12V and G12R compared with G12D. In the entire combined cohort, Kaplan-Meier analyses showed longer overall survival (OS) with KRAS G12R as compared with G12D (median OS of 1255 versus 682 days, P = .03) and in patients whose PDACs displayed P+LD morphology as compared with conventional morphology (median OS of 1175 versus 684 days, P = .04). In the adjuvant-only subset, KRAS G12R had the longest OS compared with G12D, G12V, and other alleles (median OS unreached/undefined versus 1009, 1129, and 1222 days, respectively). CONCLUSIONS.­: PDACs with different mutant KRAS alleles are associated with distinct morphologies and clinical outcomes, with KRAS G12R allele associated with P+LD morphology and longer OS when compared with G12D using Kaplan-Meier studies.

8.
Bioorg Med Chem Lett ; 23(9): 2628-31, 2013 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-23522565

RESUMO

Kisspeptins, endogenous peptide ligands for GPR54, play an important role in GnRH secretion. Since in vivo administration of kisspeptins induces increased plasma LH levels, GPR54 agonists hold promise as therapeutic agents for the treatment of hormonal secretion diseases. To facilitate the design of novel potent GPR54 ligands, residues in kisspeptins that involve in the interaction with GPR54 were investigated by kisspeptin-based photoaffinity probes. Herein, we report the design and synthesis of novel kisspeptin-based photoaffinity probes, and the application to crosslinking experiments for GPR54-expressing cells.


Assuntos
Marcadores de Afinidade/química , Kisspeptinas/agonistas , Peptídeos/química , Raios Ultravioleta , Sequência de Aminoácidos , Biotina/química , Hormônio Liberador de Gonadotropina/metabolismo , Células HEK293 , Humanos , Kisspeptinas/metabolismo , Dados de Sequência Molecular , Peptídeos/metabolismo , Ligação Proteica , Receptores de Neuropeptídeos/química , Receptores de Neuropeptídeos/metabolismo , Relação Estrutura-Atividade
9.
J Biol Chem ; 286(40): 34712-21, 2011 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-21840990

RESUMO

We have recently discovered that the insulin-like growth factor receptor I (IGF-IR) is up-regulated in human invasive bladder cancer and promotes migration and invasion of transformed urothelial cells. The proteoglycan decorin, a key component of the tumor stroma, can positively regulate the IGF-IR system in normal cells. However, there are no available data on the role of decorin in modulating IGF-IR activity in transformed cells or in tumor models. Here we show that the expression of decorin inversely correlated with IGF-IR expression in low and high grade bladder cancers (n = 20 each). Decorin bound with high affinity IGF-IR and IGF-I at distinct sites and negatively regulated IGF-IR activity in urothelial cancer cells. Nanomolar concentrations of decorin promoted down-regulation of IRS-1, one of the critical proteins of the IGF-IR pathway, and attenuated IGF-I-dependent activation of Akt and MAPK. This led to decorin-evoked inhibition of migration and invasion upon IGF-I stimulation. Notably, decorin did not cause down-regulation of the IGF-IR in bladder, breast, and squamous carcinoma cells. This indicates that decorin action on the IGF-IR differs from its known activity on other receptor tyrosine kinases such as the EGF receptor and Met. Our results provide a novel mechanism for decorin in negatively modulating both IGF-I and its receptor. Thus, decorin loss may contribute to increased IGF-IR activity in the progression of bladder cancer and perhaps other forms of cancer where IGF-IR plays a role.


Assuntos
Decorina/metabolismo , Regulação Neoplásica da Expressão Gênica , Receptor IGF Tipo 1/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Matriz Extracelular/metabolismo , Células HeLa , Humanos , Imuno-Histoquímica/métodos , Peptídeos e Proteínas de Sinalização Intercelular , Sistema de Sinalização das MAP Quinases , Modelos Biológicos , Invasividade Neoplásica , Transdução de Sinais , Neoplasias da Bexiga Urinária/metabolismo
10.
Cancer ; 118(14): 3484-93, 2012 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-22086503

RESUMO

BACKGROUND: The aim of this study was to evaluate the expression of epidermal growth factor receptor (EGFR) and insulinlike growth factor 1 receptor (IGF-1R) proteins and IGF-1R gene copy numbers in pancreatic ductal adenocarcinoma in relation to patients' characteristics and prognosis. METHODS: Immunohistochemical staining was performed on formalin-fixed paraffin-embedded tissue derived from tumor specimens recovered during surgery. Slides were evaluated for membranous EGFR and IGF-1R staining using both the HercepTest and the semiquantitative H-score systems. Chromogenic in situ hybridization was performed to quantify IGF-1R gene copy number. The primary outcome was the association between EGFR expression, IGF-1R expression-in both neoplastic epithelial and stromal cells-or IGF-1R gene copy number and overall survival. Secondary outcomes included associations between EFGR and IGF-1R expression and pathologic variables. RESULTS: A total of 105 patients were included. EGFR expression was present in 30.4% of cases and was associated with lymph node metastasis (P = .038). IGF-1R was overexpressed in 53% of tumors and correlated with higher tumor grade (P = .033). High membranous expression of EGFR (P < .001) and/or IGF-1R (P = .004), the cytoplasmic detection of EGFR (P = .027), and high expression levels of IGF-1R in the tumoral stroma (P < .001) were all associated with shorter overall survival, being significantly better in patients who simultaneously do not express membranous EGFR or stromal IGF-1R. CONCLUSIONS: EGFR and IGF-1R expression, in neoplastic and stromal cells, seems to be an important prognostic factor.


Assuntos
Carcinoma Ductal Pancreático/genética , Receptores ErbB/metabolismo , Neoplasias Pancreáticas/genética , Receptor IGF Tipo 1/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/metabolismo , Carcinoma Ductal Pancreático/mortalidade , Receptores ErbB/genética , Feminino , Dosagem de Genes , Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/mortalidade , Prognóstico , Receptor IGF Tipo 1/genética
11.
Breast Cancer Res Treat ; 135(2): 433-44, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22825030

RESUMO

Aurora kinases (AKs) regulate multiple components of mitotic cell division in eukaryotic cells. Aurora A is frequently amplified or overexpressed in breast cancer cells leading to aberrant chromosome segregation, genomic instability, and activation of oncogenic pathways. In the present studies, we determined the effects of treatment with the pan-AK inhibitor MK-0457 and/or the pan-histone deacetylase inhibitor vorinostat against human breast cancer cells that were either ER-, PR-, and HER2- (MDA-MB-468 and MDA-MB-231) or exhibited Aurora A amplification (BT-474 and MDA-MB-231 cells). Treatment with MK-0457 depleted p-AKs levels and their activity, as well as induced G2/M accumulation, DNA endoreduplication, multipolar mitotic spindles, and apoptosis of the breast cancer cells. Similar apoptotic effects were observed with treatment with the Aurora A-specific inhibitor, MLN8237. Treatment with vorinostat induced hsp90 acetylation and inhibited its chaperone association with AKs, leading to depletion of AKs and Survivin. Exposure of the siRNA to AK A also induced apoptosis, which was augmented by co-treatment with MK-0457 and vorinostat. Co-treatment with vorinostat enhanced MK-0457-mediated inhibition of the activities of Aurora A and Aurora B, leading to synergistic in vitro activity against human breast cancer cells. Co-treatment with MK-0457 and vorinostat also caused greater tumor growth inhibition and superior survival of mice bearing MDA-MB-231 xenografts. These pre-clinical findings indicate that combined treatment with a pan-AK inhibitor or an Aurora A-specific inhibitor and vorinostat represents a novel therapeutic strategy for the treatment of Aurora A-amplified and/or triple negative breast cancers.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias da Mama/tratamento farmacológico , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Apoptose/efeitos dos fármacos , Aurora Quinase A , Aurora Quinase B , Aurora Quinases , Neoplasias da Mama/enzimologia , Linhagem Celular Tumoral , Sinergismo Farmacológico , Feminino , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Dosagem de Genes , Expressão Gênica , Técnicas de Silenciamento de Genes , Proteínas de Choque Térmico HSP90/metabolismo , Humanos , Ácidos Hidroxâmicos/administração & dosagem , Proteínas Inibidoras de Apoptose/metabolismo , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Piperazinas/administração & dosagem , Ligação Proteica , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Interferência de RNA , Survivina , Vorinostat , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Bioconjug Chem ; 23(6): 1259-65, 2012 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-22486464

RESUMO

CXC chemokine receptor 4 (CXCR4) is a G protein-coupled receptor implicated in cell entry of T-cell line-tropic HIV-1 strains. CXCR4 and its ligand stromal cell derived factor-1 (SDF-1)/CXCL12 play pivotal parts in many physiological processes and pathogenetic conditions (e.g., immune cell-homing and cancer metastasis). We previously developed the potent CXCR4 antagonist T140 from structure-activity relationship studies of the antimicrobial peptide polyphemusin II. T140 and its derivatives have been exploited in biological and biomedical studies for the SDF-1/CXCR4 axis. We investigated receptor localization upon ligand stimulation using fluorescent SDF-1 and T140 derivatives as well as a specific labeling technique for cellular-membrane CXCR4. Fluorescent T140 derivatives induced translocation of CXCR4 into the perinuclear region as observed by treatment with fluorescent SDF-1. T140 derivative-mediated internalization of CXCR4 was also monitored by the coiled-coil tag-probe system. These findings demonstrated that the CXCR4 antagonistic activity and anti-HIV activity of T140 derivatives were derived (at least in part) from antagonist-mediated receptor internalization.


Assuntos
Fármacos Anti-HIV/química , Fármacos Anti-HIV/farmacologia , Peptídeos Catiônicos Antimicrobianos/química , Peptídeos Catiônicos Antimicrobianos/farmacologia , Receptores CXCR4/antagonistas & inibidores , Sequência de Aminoácidos , Animais , Células CHO , Quimiocina CXCL12/metabolismo , Cricetulus , Regulação para Baixo/efeitos dos fármacos , HIV-1/efeitos dos fármacos , Humanos , Modelos Moleculares , Dados de Sequência Molecular , Receptores CXCR4/análise , Receptores CXCR4/metabolismo , Relação Estrutura-Atividade
13.
Blood ; 116(24): 5306-15, 2010 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-20810927

RESUMO

Stromal cell derived factor-1 (SDF-1 or CXCL12) and its receptor CXCR4 are involved in the directional homing to the bone marrow niches and in peripheral mobilization of normal and transformed hematopoietic stem and myeloid progenitor cells. Elevated CXCR4 expression confers poor prognosis, whereas inhibition of CXCR4 signaling overcomes stroma-mediated chemoresistance in acute myeloid leukemia (AML). Here, we demonstrate that treatment with the pan-histone deacetylase inhibitor panobinostat (PS) depleted the mRNA and protein levels of CXCR4 in the cultured and primary AML cells. PS-induced acetylation of the heat shock protein (hsp) 90 reduced the chaperone association between CXCR4 and hsp90, directing CXCR4 to degradation by the 20S proteasome. PS treatment also depleted G protein-coupled receptor kinase 3, as well as attenuated the phosphorylation of AKT and ERK1/2 in AML cells, which was not affected by cotreatment with CXCL12. Compared with each agent alone, cotreatment with PS and CXCR4 antagonist AMD3100 or FC-131 synergistically induced apoptosis of cultured and primary AML cells. PS and FC-131 exerted more lethal effects on primary AML versus normal CD34(+) bone marrow progenitor cells. These findings support the rationale to test the in vivo efficacy of PS in enhancing the lethal effects of CXCR4 antagonists against AML cells.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Ácidos Hidroxâmicos/farmacologia , Leucemia Mieloide Aguda/tratamento farmacológico , Receptores CXCR4/antagonistas & inibidores , Apoptose/efeitos dos fármacos , Benzilaminas , Ciclamos , Sinergismo Farmacológico , Compostos Heterocíclicos/farmacologia , Inibidores de Histona Desacetilases , Humanos , Ácidos Hidroxâmicos/uso terapêutico , Indóis , Panobinostat , Peptídeos Cíclicos/farmacologia , RNA Mensageiro/antagonistas & inibidores , Receptores CXCR4/genética , Transdução de Sinais/efeitos dos fármacos , Células Tumorais Cultivadas
14.
Acta Cytol ; 56(6): 645-54, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23207443

RESUMO

OBJECTIVE: To identify new molecular diagnostic markers for non-small cell lung carcinoma (NSCLC) by analyzing microRNA (miRNA) expression profile differences in samples from NSCLC patients and adults with nonneoplastic diseases. STUDY DESIGN: miRNA expression was studied in archival formalin-fixed, paraffin-embedded tissues by microarray and confirmed by real-time PCR analysis of NSCLC and normal lung tissues. An algorithm for discriminating normal, squamous cell carcinoma (SQCC), and adenocarcinoma (ADC) tissue was derived from miRNA expression studies and applied towards characterization of poorly differentiated NSCLC samples. RESULTS: Microarray data from a genome-wide scan revealed 34 differentially expressed miRNAs, 5 of which enabled algorithmic discrimination of normal tissue from carcinoma (SQCC or ADC), as well as SQCC from ADC. Expression of miR-21 was significantly increased in both tumor types, whereas levels of miR-451 and miR-486-5p were reduced. SQCC was distinguished from normal tissue and ADC by high-level miR-205 expression and decreased miR-26b. Comparison of miRNA profiles to histological and immunohistochemical findings in 19 poorly differentiated specimens demonstrated the potential clinical utility of miRNA profiling to provide important insights into the classification of SQCC and ADC. CONCLUSION: This study presents a novel algorithm for specimen classification in cases of poorly differentiated NSCLC.


Assuntos
Adenocarcinoma/diagnóstico , Biomarcadores Tumorais/genética , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma de Células Escamosas/diagnóstico , Perfilação da Expressão Gênica , Neoplasias Pulmonares/diagnóstico , MicroRNAs/genética , Adenocarcinoma/genética , Adulto , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma de Células Escamosas/genética , Humanos , Neoplasias Pulmonares/genética , Análise de Sequência com Séries de Oligonucleotídeos , Prognóstico , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa
15.
J Exp Clin Cancer Res ; 41(1): 41, 2022 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-35086548

RESUMO

BACKGROUND: Cancer cells have an imbalance in oxidation-reduction (redox) homeostasis. Understanding the precise mechanisms and the impact of the altered redox microenvironment on the immunologic reaction to tumors is limited. METHODS: We isolated exosomes from ovarian cancer cells through ultracentrifuge and characterized by Western-blots and Nanoparticle Tracking Analysis. 2D, 3D-coculture tumor model, and 3D live cell imaging were used to study the interactions between tumor cells, macrophages and CD3 T cells in vitro. The role of exosomal miR-155-5p in tumor growth was evaluated in xenograft nude mice models and immune-competent mice models. Flow cytometry and flow sorting were used to determine the expression levels of miR-155-5p and PD-L1 in ascites and splenic macrophages, and the percentages of CD3 T cells subpopulations. RESULTS: The elevation of reactive oxygen species (ROS) greatly downregulated exosomal miR-155-5p expression in tumor cells. Neutralization of ROS with N-acetyl-L-cysteine (NAC) increased the levels of miR-155-5p in tumor exosomes that were taken up by macrophages, leading to reduction of macrophage migration and tumor spheroid infiltration. We further found that programmed death ligand 1 (PD-L1) is a functional target of miR-155-5p. Co-culture of macrophages pre-treated with NAC-derived tumor exosomes or exosomal miR-155-5p with T-lymphocytes leading to an increased percentage of CD8+ T-lymphocyte and a decreased CD3+ T cell apoptosis through PD-L1 downregulation. Tumor growth in nude mice was delayed by treatment with NAC-derived tumor exosomes. Delivery of tumor exo-miR-155-5p in immune-intact mice suppressed ovarian cancer progression and macrophage infiltration, and activated CD8+ T cell function. It is of note that exo-miR-155-5p inhibited tumor growth more potently than the PD-L1 antibody, suggesting that in addition to PD-L1, other pathways may also be targeted by this approach. CONCLUSIONS: Our findings demonstrate a novel mechanism, ROS-induced down-regulation of miR-155-5p, by which tumors modulate the microenvironment that favors tumor growth. Understanding of the negative impact of ROS on the tumor immune response will improve current therapeutic strategies. Targeting miR-155-5p can be an alternative approach to prevent formation of an immunosuppressive TME through downregulation of PD-L1 and other immunosuppressive factors.


Assuntos
Antígeno B7-H1/metabolismo , Exossomos/imunologia , Imunidade/imunologia , Macrófagos/metabolismo , MicroRNAs/metabolismo , Animais , Linhagem Celular Tumoral , Feminino , Humanos , Camundongos , Camundongos Nus , Espécies Reativas de Oxigênio
16.
Ann Diagn Pathol ; 15(1): 37-45, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21238914

RESUMO

Urovysion fluorescence in situ hybridization (UVFISH) identifies malignant cells in urine by detecting specific urothelial carcinoma-related chromosomal abnormalities. Some renal carcinomas (RCCs) share overlapping chromosomal aberrations with urothelial carcinoma. Malignant renal cells that are shed in urine can potentially cause a positive UVFISH result. We evaluated UVFISH in RCCs to determine its potential applicability to the diagnosis and grading of RCCs. Paraffin blocks from 39 RCCs (25 clear cell, 9 papillary, 2 chromophobe, and 3 sarcomatoid) and 15 controls (5 renal oncocytomas and 10 urothelial carcinomas) were tested. Of the RCCs, 15 (40%) were UVFISH-positive (9/25 [40%] clear cell, 3/9 [30%] papillary, 1/2 [50%] chromophobe, and 2/3 [67%] sarcomatoid carcinoma) and 24 (60%) were negative. Of the 15 controls, 8 (∼50%) were UVFISH-positive (2/5 [40%] oncocytomas and 6/10 [60%] urothelial carcinomas) and 7 (∼50%) were UVFISH-negative. Polysomy of chromosome 17 showed a statistically significant correlation with RCC subtype, being absent in most of the clear cell RCCs (P = .0096) compared with other RCCs. Polysomy of chromosome 7 was more frequent in high-grade than low-grade RCC (P = .0197) and more likely in high-grade clear cell than low-grade clear cell RCC (P = .0120). In conclusion, we showed that RCC has overlapping chromosomal abnormalities with urothelial carcinoma and can cause a positive UVFISH result. This has implications for the interpretation of Urovysion in patients whose urine contains malignant cells but who have negative cystoscopy and a concomitant renal mass. The chromosomal abnormalities observed in RCC are not distinct from those in urothelial carcinoma; therefore, UVFISH cannot distinguish these tumor types, nor can it type or grade RCC.


Assuntos
Carcinoma de Células Renais/patologia , Carcinoma de Células Renais/urina , Aberrações Cromossômicas , Hibridização in Situ Fluorescente/métodos , Neoplasias Renais/patologia , Idoso , Carcinoma de Células Renais/genética , Cromossomos Humanos Par 17/genética , Cromossomos Humanos Par 3/genética , Cromossomos Humanos Par 7/genética , Cromossomos Humanos Par 9/genética , Detecção Precoce de Câncer/métodos , Feminino , Humanos , Neoplasias Renais/diagnóstico , Neoplasias Renais/urina , Masculino , Pessoa de Meia-Idade , Inclusão em Parafina , Urinálise/métodos
17.
Acta Med Acad ; 50(1): 4-12, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34075760

RESUMO

OBJECTIVE: Mutations in the EIF1AX gene have been recently detected in a small percentage of benign and malignant thyroid lesions. We sought to investigate the prevalence and clinical significance of EIF1AX mutations and co-mutations in cytologically indeterminate thyroid nodules at our institution. MATERIALS AND METHODS: A 5-year retrospective analysis was performed on thyroid nodules with a cytologic diagnosis of Bethesda category III or IV, which had undergone testing by our in-house next generation sequencing panel. Surgically resected nodules with EIF1AX mutations were identified, and mutation type and presence of co-mutations were correlated with histopathologic diagnosis. RESULTS: 41/904 (4.5%) cases overall and 26/229 (11.4%) surgically resected nodules harbored an EIF1AX mutation. The most common histologic diagnoses were follicular thyroid carcinoma and follicular variant of papillary thyroid carcinoma. 11/26 (42.3%) of nodules had isolated EIF1AX mutation. Comutations were found in RAS (12/26; 46.2%), TERT (5/26; 19.2%) and TP53 (2/26; 7.7%). EIF1AX mutation alone conferred a 36.4% risk of malignancy (ROM) and 54.5% ROM or noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP), while the ROM was significantly higher in nodules with concurrent RAS (71.4%), TERT, TP53 and RAS+TERT (100%) mutations. CONCLUSION: EIF1AX mutations occur in benign and malignant follicular thyroid neoplasms. In our cohort, the majority of mutations occurred at the splice acceptor site between exons 5 and 6. Importantly, the coexistence of EIF1AX mutations with other driver pathogenic mutations in RAS, TERT and TP53 conferred a 100% ROM or NIFTP, indicating that such nodules require surgical removal.


Assuntos
Adenocarcinoma Folicular , Fator de Iniciação 1 em Eucariotos , Neoplasias da Glândula Tireoide , Nódulo da Glândula Tireoide , Fator de Iniciação 1 em Eucariotos/genética , Humanos , Mutação , Estudos Retrospectivos , Neoplasias da Glândula Tireoide/genética , Nódulo da Glândula Tireoide/genética
18.
Int J Cancer ; 127(5): 1180-7, 2010 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-20039317

RESUMO

We previously reported that the expression of CXC chemokine receptor-4 (CXCR4) was upregulated in invasive bladder cancers and that the small peptide T140 was a highly sensitive antagonist for CXCR4. In this study, we identified that CXCR4 expression was induced in high-grade superficial bladder tumors, including carcinoma in situ and invasive bladder tumors. To visualize the bladder cancer cells using urinary sediments from the patients and chemically induced mouse bladder cancer model, a novel fluorescent CXCR4 antagonist TY14003 was developed, that is a T140 derivative. TY14003 could label bladder cancer cell lines expressing CXCR4, whereas negative-control fluorescent peptides did not label them. When labeling urinary sediments from patients with invasive bladder cancer, positive-stained cells were identified in all patients with bladder cancer and positive urine cytology but not in controls. Although white blood cells in urine were also labeled with TY14003, they could be easily discriminated from urothelial cells by their shape and size. Finally, intravesical instillation of TY14003 into mouse bladder, using N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN)-induced bladder cancer model, demonstrated that fluorescent signals were detected in the focal areas of bladder of all mice examined at 12 weeks of BBN drinking by confocal microscopy and fluorescent endoscopy. On the contrary, all the normal bladders were found to be negative for TY14003 staining. In conclusion, these results indicate that TY14003 is a promising diagnostic tool to visualize small or flat high-grade superficial bladder cancer.


Assuntos
Carcinoma in Situ/diagnóstico , Diagnóstico por Imagem , Fragmentos de Peptídeos/farmacologia , Receptores CXCR4/antagonistas & inibidores , Neoplasias da Bexiga Urinária/diagnóstico , Bexiga Urinária/patologia , Animais , Western Blotting , Butilidroxibutilnitrosamina/toxicidade , Carcinoma in Situ/induzido quimicamente , Carcinoma in Situ/metabolismo , Humanos , Técnicas Imunoenzimáticas , Camundongos , Camundongos Endogâmicos C57BL , Invasividade Neoplásica , Receptores CXCR4/metabolismo , Espectrometria de Fluorescência , Células Tumorais Cultivadas , Bexiga Urinária/metabolismo , Neoplasias da Bexiga Urinária/induzido quimicamente , Neoplasias da Bexiga Urinária/metabolismo , Urina/química , Urina/citologia
19.
Arch Pathol Lab Med ; 144(11): 1303-1310, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-32649229

RESUMO

CONTEXT.­: We implemented multiple nucleic acid amplification test platforms because of the limited availability of test kits for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) during the early stages of the pandemic. Interpretation of results generated by different platforms and prioritization for testing algorithms required cross-comparison. OBJECTIVE.­: To compare the analytical sensitivity of 3 commercial SARS-CoV-2 molecular assays, selected samples were studied in parallel with Cobas SARS-CoV-2 test, NxTAG CoV Extended Panel, and ID NOW COVID-19 assays. DESIGN.­: A total of 8043 SARS-CoV-2 tests performed from March 22 to April 19, 2020, were included in this study. For all 1794 positive specimens detected by the cobas SARS-CoV-2 assay, the cycle threshold (Ct) values were manually tracked and plotted to demonstrate the distribution of sample viral levels. Additionally, 50 and 63 low-positive specimens (Ct values >32) as well as 50 and 61 consecutive positive specimens by the cobas assay were tested with NxTAG and ID NOW, respectively, to estimate their relative sensitivities. RESULTS.­: The Ct values of cobas SARS-CoV-2-positive samples were evenly distributed throughout ranges of 13.32 to 39.50 (mean, 25.06) and 13.60 to 42.49 (mean, 26.45) for ORF1 and E gene targets, respectively. NxTAG reliably detected only specimens with E gene Ct values lower than 33, and is estimated to detect 89.4% of positive specimens detected by cobas assay. ID NOW had performance variation independent of Ct value and is estimated to detect 83.5% of cobas positives. CONCLUSIONS.­: Clinical specimens exhibit a wide range of viral burden, with a significant portion at low levels. Analytical sensitivity of testing platforms is critical for reliable detection of SARS-CoV-2 and uniform care to patients.


Assuntos
Betacoronavirus/genética , Infecções por Coronavirus/diagnóstico , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Amplificação de Ácido Nucleico/métodos , Pneumonia Viral/diagnóstico , Síndrome Respiratória Aguda Grave/diagnóstico , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/genética , Adulto , Betacoronavirus/isolamento & purificação , Betacoronavirus/fisiologia , COVID-19 , Técnicas de Laboratório Clínico/métodos , Infecções por Coronavirus/virologia , Diagnóstico Diferencial , Diagnóstico Precoce , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nasofaringe/patologia , Nasofaringe/virologia , Pandemias , Pneumonia Viral/virologia , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/isolamento & purificação , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/fisiologia , SARS-CoV-2 , Sensibilidade e Especificidade , Síndrome Respiratória Aguda Grave/virologia , Manejo de Espécimes/instrumentação , Manejo de Espécimes/métodos
20.
Oncogene ; 39(49): 7181-7195, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33037411

RESUMO

The development of resistance to EGFR Tyrosine kinase inhibitors (TKIs) in NSCLC with activating EGFR mutations is a critical limitation of this therapy. In addition to genetic alterations such as EGFR secondary mutation causing EGFR-TKI resistance, compensatory activation of signaling pathways without interruption of genome integrity remains to be defined. In this study, we identified S6K1/MDM2 signaling axis as a novel bypass mechanism for the development of EGFR-TKI resistance. The observation of S6K1 as a candidate mechanism for resistance to EGFR TKI therapy was investigated by interrogation of public databases and a clinical cohort to establish S6K1 expression as a prognostic/predictive biomarker. The role of S6K1 in TKI resistance was determined in in vitro gain-and-loss of function studies and confirmed in subcutaneous and orthotopic mouse lung cancer models. Blockade of S6K1 by a specific inhibitor PF-4708671 synergistically enhanced the efficacy of TKI without showing toxicity. The mechanistic study showed the inhibition of EGFR caused nuclear translocation of S6K1 for binding with MDM2 in resistant cells. MDM2 is a downstream effector of S6K1-mediated TKI resistance. Taken together, we present evidence for the reversal of resistance to EGFR TKI by the addition of small molecule S6K1/MDM2 antagonists that could have clinical benefit.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/patologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Neoplasias Pulmonares/patologia , Inibidores de Proteínas Quinases/farmacologia , Proteínas Quinases S6 Ribossômicas 70-kDa/antagonistas & inibidores , Adulto , Animais , Linhagem Celular Tumoral , Transformação Celular Neoplásica , Receptores ErbB/antagonistas & inibidores , Humanos , Masculino , Camundongos , Mutação , Prognóstico , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos
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