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2.
Blood Adv ; 5(21): 4447-4455, 2021 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-34607345

RESUMO

Natural killer (NK) cells are a population of innate immune cells that can rapidly kill cancer cells and produce cytokines such as interferon-γ. A key feature of NK cells is their ability to respond without prior sensitization; however, it is now well established that NK cells can possess memory-like features. After activation with cytokines, NK cells demonstrate enhanced effector functions upon restimulation days or weeks later. This demonstrates that NK cells may be trained to be more effective killers and harnessed as more potent cancer immunotherapy agents. We have previously demonstrated that cellular metabolism is essential for NK cell responses, with NK cells upregulating both glycolysis and oxidative phosphorylation upon cytokine stimulation. Limiting NK cell metabolism results in reduced cytotoxicity and cytokine production. We have also demonstrated that defective NK cell responses in obesity are linked to defective cellular metabolism. In the current study, we investigated if cellular metabolism is required during the initial period of NK cell cytokine training and if NK cells from people with obesity (PWO) can be effectively trained. We show that increased flux through glycolysis and oxidative phosphorylation during the initial cytokine activation period is essential for NK cell training, as is the metabolic signaling factor Srebp. We show that NK cells from PWO, which are metabolically defective, display impaired NK cell training, which may have implications for immunotherapy in this particularly vulnerable group.


Assuntos
Interferon gama , Células Matadoras Naturais , Células Cultivadas , Citocinas , Humanos , Obesidade/terapia
3.
Pan Afr Med J ; 36: 299, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33117493

RESUMO

Chlamydia and gonorrhea are common sexually transmitted infections (STIs) that can cause multiple problems, and can be easily treated, but frequently present without symptoms. Because of this, commonly used syndromic diagnosis misses a majority of infected persons. Previously, diagnostic tests were expensive and invasive, but newer nucleic-acid amplification tests (NAATs) are available that use urine to non-invasively test for these infections. These analyses used data from seroprevalence studies conducted in five militaries. Data included self-reported current symptoms of STIs as well as chlamydia and gonorrhea NAAT results. A total of 4923 men were screened for chlamydia and gonorrhea from these 5 militaries during April 2016 to October 2017. The combined prevalence of chlamydia and gonorrhea in these five militaries ranged from 2.3% in Burundi to 11.9% in Belize. These infections were not successfully identified by symptomology; for example, only 2% of cases in Belize reported symptoms. In three of the five countries there was no statistical association between symptoms and positive NAAT results. The majority of individuals with these infections (81% to 98%) would be undiagnosed and untreated using only symptomology. Therefore, using symptoms alone to diagnose cases of chlamydia and gonorrhea is not an effective way to control these infections. We propose that automated, cartridge-based NAATs, be considered for routine use in diagnosing those at risk for STIs.


Assuntos
Infecções por Chlamydia/epidemiologia , Gonorreia/epidemiologia , Técnicas de Amplificação de Ácido Nucleico , Assunção de Riscos , Infecções Sexualmente Transmissíveis/diagnóstico , Adolescente , Adulto , Idoso , Belize/epidemiologia , Benin/epidemiologia , Burundi/epidemiologia , Infecções por Chlamydia/diagnóstico , Infecções por Chlamydia/transmissão , Chlamydia trachomatis/genética , Chlamydia trachomatis/imunologia , Chlamydia trachomatis/isolamento & purificação , Testes Diagnósticos de Rotina/métodos , República Dominicana/epidemiologia , Gana/epidemiologia , Gonorreia/diagnóstico , Gonorreia/transmissão , Humanos , Masculino , Programas de Rastreamento/métodos , Pessoa de Meia-Idade , Instalações Militares/estatística & dados numéricos , Militares/estatística & dados numéricos , Neisseria gonorrhoeae/genética , Neisseria gonorrhoeae/imunologia , Neisseria gonorrhoeae/isolamento & purificação , Técnicas de Amplificação de Ácido Nucleico/métodos , Estudos Soroepidemiológicos , Comportamento Sexual/estatística & dados numéricos , Infecções Sexualmente Transmissíveis/epidemiologia , Infecções Sexualmente Transmissíveis/microbiologia , Inquéritos e Questionários , Adulto Jovem
5.
J Immunol ; 202(12): 3404-3411, 2019 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-31076528

RESUMO

Obesity underpins the development of numerous chronic diseases, such as type II diabetes mellitus. It is well established that obesity negatively alters immune cell frequencies and functions. Mucosal-associated invariant T (MAIT) cells are a population of innate T cells, which we have previously reported are dysregulated in obesity, with altered circulating and adipose tissue frequencies and a reduction in their IFN-γ production, which is a critical effector function of MAIT cells in host defense. Hence, there is increased urgency to characterize the key molecular mechanisms that drive MAIT cell effector functions and to identify those which are impaired in the obesity setting. In this study, we found that MAIT cells significantly upregulate their rates of glycolysis upon activation in an mTORC1-dependent manner, and this is essential for MAIT cell IFN-γ production. Furthermore, we show that mTORC1 activation is dependent on amino acid transport via SLC7A5. In obese patients, using RNA sequencing, Seahorse analysis, and a series of in vitro experiments, we demonstrate that MAIT cells isolated from obese adults display defective glycolytic metabolism, mTORC1 signaling, and SLC7A5 aa transport. Collectively, our data detail the intrinsic metabolic pathways controlling MAIT cell cytokine production and highlight mTORC1 as an important metabolic regulator that is impaired in obesity, leading to altered MAIT cell responses.


Assuntos
Diabetes Mellitus Tipo 2/imunologia , Transportador 1 de Aminoácidos Neutros Grandes/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Células T Invariantes Associadas à Mucosa/fisiologia , Obesidade/imunologia , Adulto , Células Cultivadas , Feminino , Glicólise , Humanos , Interferon gama/metabolismo , Ativação Linfocitária , Masculino , Análise de Sequência de RNA , Transdução de Sinais
6.
Clin Linguist Phon ; 33(1-2): 175-190, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30047781

RESUMO

This pilot study aims to evaluate the effectiveness of a school-based intervention using visual strategies for improving accurate use of auxiliary and copula marking in singular and plural, past and present tense by students with moderate learning disability and complex needs. Eleven students, aged 10-14 years, in a specialist school based in the UK, participated in the study. A within participants design was used which included testing at baseline, pre- and post-intervention to consider progress with intervention as compared with progress during a baseline period of similar length. The experimental intervention consisted of eight, bi-weekly, 20 minute sessions, over a four week period, in small groups, in a classroom setting. Half of the participants focused on the auxiliary and half on the copula, but all were tested on both. Techniques included the use of visual templates and rules (the Shape CodingTM system) to support explicit instruction. Eight participants made greater progress during the intervention term than during the baseline term and this was significant at a group level (d = 0.92). A comparison of progress to zero was not significant during the baseline period (d = 0.15) but was during the intervention period (d = 1.07). Progress also appeared to generalise from the targeted to non-targeted structure. This pilot study therefore provides preliminary evidence that older students with complex needs can make progress with morphology when intervention includes explicit instruction and visual templates and that generalisation may be observed.


Assuntos
Transtornos do Desenvolvimento da Linguagem/terapia , Linguística , Instituições Acadêmicas , Ansiedade , Criança , Humanos , Projetos Piloto , Reino Unido
7.
J Trauma Stress ; 31(2): 296-306, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29603393

RESUMO

Research has shown combat exposure to be associated with negative mental health outcomes. Different combat exposure measures are not composed of the same combat experiences, and few combat exposure measures have been directly compared to another measure. Furthermore, research about the unique associations between specific combat experiences and mental health is lacking. We investigated associations between new-onset posttraumatic stress disorder (PTSD), new-onset depression, and alcohol-related problems and two commonly used measures of combat among a sample of 20,719 recently deployed U.S. military personnel. A 13-item measure assessed both direct and indirect combat exposures, and a 5-item measure assessed only indirect exposures. Both combat measures were associated with all outcomes in the same direction (e.g., PTSD, odds ratio [OR] = 2.97 vs. 4.01; depression, OR = 2.03 vs. 2.42; alcohol-related problems, OR = 1.41 vs. 1.62, respectively, for the 5- and 13-item measures). The 13-item measure had a stronger association with some outcomes, particularly PTSD. Each specific item had significant bivariate associations with all outcomes, ORs = 1.43-4.92. After adjusting for other combat exposures, items assessing witnessing abuse, feeling in danger, and knowing someone injured or killed remained associated with all outcomes, ORs = 1.18-2.72. After this adjustment, several items had unexpected protective associations with some mental health outcomes. Results indicated these two combat exposure measures were approximately equally effective for determining risk for negative mental health outcomes in a deployed population, despite having different content. Additional research is needed to replicate and understand how specific combat exposures affect health.


Assuntos
Alcoolismo/epidemiologia , Depressão/epidemiologia , Militares/estatística & dados numéricos , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Inquéritos e Questionários , Exposição à Guerra , Adulto , Análise Fatorial , Feminino , Humanos , Masculino , Militares/psicologia , Razão de Chances , Medição de Risco/métodos , Estados Unidos/epidemiologia
8.
JCI Insight ; 2(24)2017 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-29263296

RESUMO

Childhood obesity is a major global concern, with over 50 million children now classified as obese. Obesity has been linked to the development of numerous chronic inflammatory diseases, including type 2 diabetes and multiple cancers. NK cells are a subset of innate effector cells, which play an important role in the regulation of adipose tissue and antitumor immunity. NK cells can spontaneously kill transformed cells and coordinate subsequent immune responses through their production of cytokines. We investigated the effect of obesity on NK cells in a cohort of obese children, compared to children with a healthy weight. We demonstrated a reduction in peripheral NK cell frequencies in childhood obesity and inverse correlations with body mass index and insulin resistance. Compared with NK cells from children with normal weight, we show increased NK cell activation and metabolism in obese children (PD-1, mTOR activation, ECAR, and mitochondrial ROS), along with a reduced capacity to respond to stimulus, ultimately leading to loss of function (proliferation and tumor lysis). Collectively we show that NK cells from obese children are activated, metabolically stressed, and losing the ability to perform their basic duties. Paired with the reduction in NK cell frequencies in childhood obesity, this suggests that the negative effect on antitumor immunity is present early in the life course of obesity and certainly many years before the development of overt malignancies.


Assuntos
Células Matadoras Naturais/imunologia , Obesidade Infantil/imunologia , Adolescente , Índice de Massa Corporal , Criança , Citotoxicidade Imunológica , Feminino , Humanos , Resistência à Insulina/imunologia , Células K562/imunologia , Ativação Linfocitária/imunologia , Contagem de Linfócitos , Masculino
9.
BMC Med Res Methodol ; 17(1): 69, 2017 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-28427350

RESUMO

BACKGROUND: Posttraumatic growth is the positive change resulting from traumatic experiences and is typically assessed with retrospective measures like the Posttraumatic Growth Inventory (PTGI). The PTGI was designed to include reference to a specific traumatic event, making it difficult to implement, without change, in prospective survey studies. Thus, a modified Posttraumatic Growth Inventory-Short Form (PTGI-SF) was included in a large prospective study of current and former U.S. military personnel. The current study provides preliminary psychometric data for this modified measure and its ability to assess psychological well-being at a single time point. METHODS: The study population (N = 135,843) was randomly and equally split into exploratory and confirmatory samples that were proportionately balanced on trauma criterion. Exploratory factor analysis and confirmatory factor analysis (CFA) were performed to assess the psychometric validity of the modified measure. The final model was also assessed in a subset of the confirmatory sample with a history of trauma using CFA. RESULTS: Results supported a single-factor model with two additional correlations between items assessing spirituality and items assessing compassion/appreciation for others. This model also fits among the subset with a history of trauma. The resulting measure was strongly associated with social support and personal mastery. CONCLUSIONS: The modified PTGI-SF in this study captures psychological well-being in cross-sectional assessments, in addition to being able to measure posttraumatic growth with multiple assessments. Results indicate that the modified measure is represented by a single factor, but that items assessing spirituality and compassion/appreciation for others may be used alone to better capture these constructs.


Assuntos
Militares/psicologia , Psicometria/métodos , Qualidade de Vida/psicologia , Transtornos de Estresse Pós-Traumáticos/psicologia , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Inquéritos e Questionários , Estados Unidos
10.
Eur J Pharmacol ; 800: 1-8, 2017 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-28088384

RESUMO

RTC-1 has recently been identified as a member of a new class of anti-diabetic compounds acting through the inhibition of complex I of the mitochondrial respiratory chain (NADH:ubiquinone oxidoreductase) to improve glucose handling and inhibit weight gain in mice fed a high-fat diet (HFD). The exact mechanism by which the reduced activity of NADH:ubiquinone oxidoreductase, in response to RTC-1, promotes these improved metabolic parameters remains to be established. Through extensive in vitro analysis, new molecular insights into these downstream signalling pathways have been obtained. RTC-1-induced inhibition of NADH:ubiquinone oxidoreductase was found to promote glucose uptake in C2C12 myotubes in vitro, through the activation of the Akt substrate of 160kDa (AS160), in response to the increased activity of Akt and AMP-activated protein kinase (AMPK). RTC-1-induced phosphorylation of the AMPK substrate, acetyl-CoA carboxylase (ACC) in vitro, was associated with a decrease in lipid accumulation in 3T3-L1 adipocytes and murine mesenchymal stromal cells (MSC). The novel compound also prevented tumour necrosis factor-alpha (TNF-α)-induced insulin resistance and demonstrated insulin sensitising effects in C2C12 myotubes. Taken together, these results present a systematic analysis of the signalling mechanisms responsible for the potent anti-diabetic and anti-obesogenic effects of this modulator of mitochondrial function, strengthening the potential use of such compounds for the treatment of type 2 diabetes mellitus (T2DM).


Assuntos
Complexo I de Transporte de Elétrons/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Resistência à Insulina , Metabolismo dos Lipídeos/efeitos dos fármacos , Piperazinas/farmacologia , Tiofenos/farmacologia , Fator de Necrose Tumoral alfa/farmacologia , Células 3T3-L1 , Animais , Diabetes Mellitus Tipo 2/tratamento farmacológico , Metabolismo Energético/efeitos dos fármacos , Inibidores Enzimáticos/uso terapêutico , Feminino , Camundongos , Piperazinas/uso terapêutico , Tiofenos/uso terapêutico
11.
Ann Clin Psychiatry ; 28(4): 245-254, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27490838

RESUMO

BACKGROUND: The objective of the study was to determine if DSM-5-defined attenuated psychosis syndrome (APS) could identify individuals with prodromal psychosis and predict conversion to schizophrenia spectrum disorders at a rate similar to that observed in previous studies that utilized structured interviews and specialized rating scales. METHODS: A retrospective review of patients' medical records was used to identify individuals meeting diagnostic criteria for the APS, followed by further evaluation 2 to 3 years after the initial diagnosis, to determine if they converted to schizophrenia spectrum disorders. Results then were compared with previous studies. RESULTS: Of our study population, 43.4% converted to schizophrenia or schizoaffective disorder 2 to 3 years after initial diagnosis of APS. Comparison at the 3-year mark indicated that there was no significant difference between our observed rates and previously published conversion rates (P = .066). Three covariates were found to increase significantly the rates of conversion when added to the APS criteria: Cannabis use (P = .048), lack of previous Axis I diagnosis (P = .005), and lack of previous treatment with psychotropic medications (P = .009). CONCLUSIONS: APS accurately predicts conversion to full-scale schizophrenia spectrum disorders at a rate similar to that observed in previous studies using structured interviews and specialized rating scales.


Assuntos
Manual Diagnóstico e Estatístico de Transtornos Mentais , Transtornos Psicóticos/diagnóstico , Transtornos Psicóticos/epidemiologia , Feminino , Humanos , Masculino , Escalas de Graduação Psiquiátrica , Estudos Retrospectivos , Fatores de Tempo , Adulto Jovem
12.
J Immunol ; 194(12): 5775-80, 2015 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-25980010

RESUMO

Mucosal-associated invariant T (MAIT) cells are innate MHC-unrestricted cells that regulate inflammatory responses through the rapid production of cytokines. In this article, we show that circulating MAIT cells are depleted in obese adults, and depletion is associated with diabetic status. Circulating MAIT cells more frequently produced IL-17 upon stimulation ex vivo, a cytokine implicated in insulin resistance. MAIT cells were enriched in adipose tissue (AT) compared with blood. AT MAIT cells, but not circulating MAIT cells, were capable of producing IL-10. In AT from obese subjects, MAIT cells were depleted, were less likely to produce IL-10, and more frequently produced IL-17. Finally, we show that IL-17(+) MAIT cells are also increased in childhood obesity, and altered MAIT cell frequencies in obese children are positively associated with insulin resistance. These data indicate that MAIT cells are enriched in human AT and display an IL-17(+) phenotype in both obese adults and children, correlating with levels of insulin resistance. The alterations in MAIT cells may be contributing to obesity-related sterile inflammation and insulin resistance.


Assuntos
Interleucina-17/biossíntese , Mucosa/imunologia , Obesidade/imunologia , Obesidade/metabolismo , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Adolescente , Adulto , Fatores Etários , Estudos de Casos e Controles , Criança , Citocinas/biossíntese , Feminino , Humanos , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Mucosa/metabolismo , Fenótipo
13.
Stem Cell Res Ther ; 6: 19, 2015 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-25890330

RESUMO

INTRODUCTION: Mesenchymal stromal cells (MSC) have well defined immunomodulatory properties including the suppression of lymphocyte proliferation and inhibition of dendritic cell (DC) maturation involving both cell contact and soluble factors. These properties have made MSC attractive candidates for cellular therapy. However, the mechanism underlying these characteristics remains unclear. This study sought to investigate the mechanisms by which MSC induce a regulatory environment. METHOD: Allogeneic bone marrow mesenchymal stromal cells were cultured with T cells or dendritic cells in the presence or absence of gamma secretase inhibitor to block Notch receptor signalling. T cells and dendritic cells were examined by flow cytometry for changes in phenotype marker expression. Stable knock down MSC were generated to examine the influence of Jagged 1 signalling by MSC. Both wildtype and knockdown MSC were subsequently used in vivo in an animal model of allergic airway inflammation. RESULTS: The Notch ligand Jagged-1 was demonstrated to be involved in MSC expansion of regulatory T cells (Treg). Additionally, MSC-induced a functional semi-mature DC phenotype, which further required Notch signalling for the expansion of Treg. MSC, but not Jagged-1 knock down MSC, reduced pathology in a mouse model of allergic airway inflammation. Protection mediated by MSC was associated with enhanced Treg in the lung and significantly increased production of interleukin (IL)-10 in splenocytes re-stimulated with allergen. Significantly less Treg and IL-10 was observed in mice treated with Jagged-1 knock down MSC. CONCLUSIONS: The current study suggests that MSC-mediated immune modulation involves the education and expansion of regulatory immune cells in a Jagged-1 dependent manner and provides the first report of the importance of Jagged-1 signalling in MSC protection against inflammation in vivo.


Assuntos
Proteínas de Ligação ao Cálcio/genética , Células Dendríticas/imunologia , Peptídeos e Proteínas de Sinalização Intercelular/genética , Proteínas de Membrana/genética , Células-Tronco Mesenquimais/imunologia , Pneumonia/imunologia , Linfócitos T Reguladores/imunologia , Animais , Linhagem Celular , Proliferação de Células , Células Dendríticas/citologia , Feminino , Fatores de Transcrição Forkhead/metabolismo , Células HEK293 , Humanos , Tolerância Imunológica/imunologia , Interleucina-10/imunologia , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Proteína Jagged-1 , Pulmão/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Ovalbumina/administração & dosagem , Interferência de RNA , RNA Interferente Pequeno , Receptores Notch/metabolismo , Proteínas Serrate-Jagged , Transdução de Sinais , Linfócitos T Reguladores/citologia
14.
Ann Surg Oncol ; 22(5): 1716-21, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25145504

RESUMO

BACKGROUND: Long-term survival of patients with appendiceal or colorectal peritoneal carcinomatosis (PC) may be achieved by combining cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS/HIPEC). Unfortunately, such favorable outcomes are realized in a minority of patients. Given the morbidity of the CRS/HIPEC and the uncertain role of postresection systemic therapy, it is important that prognostic factors in high-grade PC be clearly defined. METHODS: This single center, retrospective, cohort study examined the outcomes of CRS/HIPEC performed on patients with high-grade PC secondary to appendiceal or colorectal adenocarcinoma between 2007 and 2013. Cox regression analysis was utilized to evaluate the association between potential prognostic factors [age, sex, primary site, lymph node (LN) status, peritoneal cancer index (PCI) score, completeness of cytoreduction score (CC score), number of visceral resections, and systemic chemotherapy] and progression-free survival (PFS). RESULTS: A total of 70 patients with high-grade appendiceal or colorectal PC underwent CRS/HIPEC during the study period; 82.9 % underwent complete (CC-0) cytoreduction with a median PFS of 9.7 months. Positive LNs at the time of CRS/HIPEC were predictors of worse PFS on univariate and multivariate analysis. No association was demonstrated between pre- or post-HIPEC systemic chemotherapy and PFS. CONCLUSIONS: High-grade PC secondary to appendiceal or colorectal adenocarcinoma can be managed with CRS/HIPEC. The number of LN metastases at the time of CRS/HIPEC is the strongest predictor of progression and must be considered when determining patient eligibility for this aggressive treatment.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias do Apêndice/patologia , Neoplasias Colorretais/patologia , Procedimentos Cirúrgicos de Citorredução/efeitos adversos , Hipertermia Induzida/efeitos adversos , Neoplasias Peritoneais/secundário , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Adenocarcinoma/terapia , Adenocarcinoma Mucinoso/mortalidade , Adenocarcinoma Mucinoso/patologia , Adenocarcinoma Mucinoso/terapia , Adulto , Idoso , Neoplasias do Apêndice/mortalidade , Neoplasias do Apêndice/terapia , Carcinoma de Células em Anel de Sinete/mortalidade , Carcinoma de Células em Anel de Sinete/patologia , Carcinoma de Células em Anel de Sinete/terapia , Quimioterapia Adjuvante , Quimioterapia do Câncer por Perfusão Regional , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/terapia , Terapia Combinada , Progressão da Doença , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Peritoneais/mortalidade , Neoplasias Peritoneais/terapia , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida
15.
Arch Gynecol Obstet ; 288(2): 393-400, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23435724

RESUMO

PURPOSE: We investigated the effects of the anti-epilepsy drug valproic acid (VPA) alone and in combination in treating cervical cancer. METHODS: VPA was investigated for its effects on cervical cancer Hela cell proliferation and tumor growth via in vitro and in vivo assays. RESULTS: VPA induce cell growth suppression and cell cycle arrest, with an increase of Notch1 that acts as a tumor suppressor and the change of other tumor-associated genes such as p21, p63 and PCNA. VPA was also found to induce cell morphological change, with an increase of certain cell transformation markers such as snail1, snail2 and N-cadherin. Moreover, VPA could significantly up-regulate somatostatin receptor type II (SSTR2). Our in vivo study further demonstrated that VPA via inducing SSTR2 up-regulation extremely enhanced the anti-tumor ability of the SSTR2-preferential cytotoxic COL-SST conjugate in xenografts. CONCLUSIONS: VPA could not only suppress tumor progression but also provide a novel promising therapeutic choice in combination with a receptor-targeted cytotoxic conjugate via activating the specific receptor.


Assuntos
Anticonvulsivantes/farmacologia , Carcinoma/tratamento farmacológico , Receptor Notch1/metabolismo , Receptores de Somatostatina/metabolismo , Transdução de Sinais/efeitos dos fármacos , Ácido Valproico/farmacologia , Animais , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Colchicina/uso terapêutico , Inibidor de Quinase Dependente de Ciclina p21/genética , Ciclo-Oxigenase 2/metabolismo , Combinação de Medicamentos , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Expressão Gênica , Genes p53/efeitos dos fármacos , Células HeLa , Hormônios/uso terapêutico , Humanos , Proteínas de Membrana/genética , Camundongos , Camundongos Nus , PTEN Fosfo-Hidrolase/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , RNA Mensageiro/metabolismo , Receptor Notch1/genética , Somatostatina/uso terapêutico , Moduladores de Tubulina/uso terapêutico
16.
Oncologist ; 17(2): 220-32, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22291092

RESUMO

The role of Notch signaling in cervical cancer is seemingly controversial. To confirm the function of Notch signaling in this type of cancer, we established a stable Notch1-activated cervical cancer HeLa cell line. We found that Notch1 activation resulted in apoptosis, cell cycle arrest, and tumor suppression. At the molecular level, we found that a variety of genes associated with cyclic AMP, G protein-coupled receptor, and cancer signaling pathways contributed to Notch1-mediated tumor suppression. We observed that the expression of somatostatin (SST) was dramatically induced by Notch1 signaling activation, which was accompanied by enhanced expression of the cognate SST receptor subtype 1 (SSTR1) and SSTR2. Certain genes, such as tumor protein 63 (TP63, p63), were upregulated, whereas others, such as B-cell lymphoma 2 (BCL-2), Myc, Akt, and STAT3, were downregulated. Subsequently, knockdown of Notch1-induced SST reversed Notch1-induced decrease of BCL-2 and increase of p63, indicating that Notch1-induced tumor suppression may be partly through upregulating SST signaling. Our findings support a possible crosstalk between Notch signaling and SST signaling. Moreover, Notch-induced SSTR activation could enhance SSTR-targeted cancer chemotherapy. Valproic acid (VPA), a histone deacetylase inhibitor, suppressed cell growth and upregulated the expression of Notch1 and SSTR2. A combination therapy with VPA and the SSTR2-targeting cytotoxic conjugate CPT-SST strongly led to greater suppression, as compared to each alone. Our findings thus provide us with a promising clinical opportunity for enhanced cancer therapy using combinations of Notch1-activating agents and SSTR2-targeting agents.


Assuntos
Receptor Notch1/fisiologia , Receptores de Somatostatina/fisiologia , Transdução de Sinais/fisiologia , Somatostatina/fisiologia , Neoplasias do Colo do Útero/prevenção & controle , Animais , Pontos de Checagem do Ciclo Celular , Proliferação de Células , Colforsina/farmacologia , AMP Cíclico/metabolismo , Feminino , Células HeLa , Humanos , Camundongos , Receptores de Somatostatina/antagonistas & inibidores , Neoplasias do Colo do Útero/patologia
17.
J Drug Target ; 19(8): 719-30, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21830941

RESUMO

Many tumors highly express specific populations of G-protein-coupled receptors (GPCRs) that could be utilized for receptor-targeted therapy. We confirmed significant quantities of mRNAs specific for certain somatostatin (SST), vasoactive intestinal peptide (VIP), and bombesin (BN) receptors in various commercially available tumor cell lines. Very few of the tumor cell lines examined displayed the high receptor-binding affinity despite exhibiting the expression of appropriate mRNAs and proteins of the cognate receptors. However, binding assays establish that some tumor cell lines, such as pancreatic cancer CFPAC-1, prostate cancer DU-145, and pancreatic carcinoid BON, demonstrate high BN receptor binding. BON cells also demonstrate high somatostatin receptor (SSTR) affinity binding. We also found that tumor cell lines, such as BON and host cells expressing SST receptor subtypes 1 or 2 (CHO-R1 or CHO-R2), underwent a decrease in cell surface receptor density in multiple passages. BON and CHO-R2 cells also rapidly internalize a significant proportion of cell surface ligand-receptor complexes. The tumor cells CFPAC-1, DU-145, and BON with high receptor binding could be useful for peptide drug studies. BON cells were further applied to test SST/BN analogs and cytotoxic conjugates. Furthermore, the in vivo antitumor assay showed that the cytotoxic conjugate CPT-SST targeting all SSTR subtypes displayed a potent tumor-suppressive ability to BON tumors expressing multiple SSTR subtypes.


Assuntos
Antineoplásicos , Descoberta de Drogas/métodos , Receptores da Bombesina/metabolismo , Receptores de Somatostatina/metabolismo , Receptores de Peptídeo Intestinal Vasoativo/metabolismo , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Western Blotting , Bombesina/análogos & derivados , Bombesina/química , Técnicas de Cultura de Células , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Portadores de Fármacos/química , Ligantes , Camundongos , Camundongos Nus , Terapia de Alvo Molecular , Ligação Proteica , Reação em Cadeia da Polimerase em Tempo Real , Receptores da Bombesina/biossíntese , Receptores de Somatostatina/biossíntese , Receptores de Peptídeo Intestinal Vasoativo/biossíntese , Somatostatina/análogos & derivados , Somatostatina/química , Ensaios Antitumorais Modelo de Xenoenxerto
18.
J Drug Target ; 19(8): 666-74, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21083509

RESUMO

In our previous study, we found that several tumor cell lines displayed high receptor-specific binding affinity, one of which, the human pancreatic carcinoid BON cell line, demonstrates high affinity binding of the bombesin (BN) and somatostatin (SST) receptor-specific ligands. In the present study, BON cells, as a representative model, were further applied to evaluate various peptide analogs and cytotoxic receptor-targeted peptide conjugates. We observed quick ligand-receptor internalization in BON cells as well as high binding affinity. Furthermore, BON cells have high expression of multidrug resistance-associated genes (MDR1) and show camptothecin (CPT) resistance. Various receptor-specific cytotoxic conjugates were synthesized and evaluated in the BON cell model via in vitro and in vivo studies. We found that all the tested conjugates displayed potent antitumor ability in xenografts. Especially, the CPT conjugates, CPT-SST, and CPT-BN, are most likely to increase sensitivity to CPT-resistant BON cells. Our findings suggest that appropriately defined tumor cell lines may provide physiologically relevant cell-based evaluations of novel peptide analogs and receptor-targeted chemotherapeutics.


Assuntos
Antineoplásicos Fitogênicos/administração & dosagem , Bombesina/química , Portadores de Fármacos/química , Desenho de Fármacos , Neoplasias Pancreáticas/metabolismo , Receptores de Superfície Celular/metabolismo , Somatostatina/química , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/uso terapêutico , Bibenzilas/administração & dosagem , Bibenzilas/química , Bibenzilas/uso terapêutico , Camptotecina/administração & dosagem , Camptotecina/química , Camptotecina/uso terapêutico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Humanos , Ligantes , Camundongos , Camundongos Nus , Terapia de Alvo Molecular , Ligação Proteica , Reação em Cadeia da Polimerase em Tempo Real , Receptores da Bombesina/metabolismo , Receptores de Somatostatina/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Cancer Immunol Immunother ; 59(7): 1109-20, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20306041

RESUMO

Vgamma9Vdelta2 T cells respond to pyrophosphate antigens and display potent antitumour activity in vitro. We have investigated the potential of the most potent phosphoantigen known to activate Vgamma9Vdelta2 T cells, (E)-4-hydroxy-3-methyl-but-2 enyl pyrophosphate (HMB-PP), as an adjuvant for dendritic cell (DC)-based vaccines. A single stimulation of peripheral blood mononuclear cells with HMB-PP and IL-2 was sufficient to generate lines of effector memory Vgamma9Vdelta2 T cells that retained their cytolytic and cytokine secretion activities. These cells induced differentiation of DC into semi-mature antigen-presenting cells expressing CD86, CD11c, CD54, HLA-DR, CD83 and CD40, which secreted low levels of bioactive IL-12 but no IL-10. Vgamma9Vdelta2 T cells also strongly costimulated IL-12 release but inhibited IL-10 production by lipopolysaccharide (LPS)-stimulated DC. When substituted for Vgamma9Vdelta2 T cells, IFN-gamma did not induce full DC maturation but it augmented IL-12 and inhibited IL-10 release by LPS-stimulated DC, in a manner similar to HMB-PP-activated Vgamma9Vdelta2 T cells. Our findings indicate that Vgamma9Vdelta2 T cells, stimulated with nanomolar concentrations of HMB-PP, strongly promote T helper type 1 (Th1) responses through their ability to induce DC maturation and IL-12 secretion. This adjuvant activity may prove useful in DC-based cancer therapies.


Assuntos
Células Dendríticas/imunologia , Difosfatos/imunologia , Linfócitos T/imunologia , Células Th1/imunologia , Células Apresentadoras de Antígenos/citologia , Células Apresentadoras de Antígenos/imunologia , Células Apresentadoras de Antígenos/metabolismo , Antígeno B7-2/imunologia , Antígeno CD11c/imunologia , Diferenciação Celular/imunologia , Células Cultivadas , Células Dendríticas/citologia , Células Dendríticas/metabolismo , Difosfatos/farmacologia , Citometria de Fluxo , Antígenos HLA-DR/imunologia , Humanos , Interleucina-10/metabolismo , Interleucina-12/metabolismo , Monócitos/citologia , Monócitos/imunologia , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Linfócitos T/citologia , Linfócitos T/efeitos dos fármacos , Células Th1/citologia
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