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1.
Lancet Haematol ; 8(5): e334-e343, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33894169

RESUMO

BACKGROUND: There are no approved treatments for vaso-occlusive crises in sickle cell disease. Sevuparin is a novel non-anticoagulant low molecular weight heparinoid, with anti-adhesive properties. In this study, we tested whether sevuparin could shorten vaso-occlusive crisis duration in hospitalised patients with sickle cell disease. METHODS: We did a multicentre, double-blinded, placebo-controlled, phase 2 study in 16 public access clinical hospitals in the Netherlands, Lebanon, Turkey, Bahrain, Oman, Saudi Arabia, and Jamaica. Patients aged 12-50 years with a diagnosis of sickle cell disease (types HbSS, HbSC, HbSß0-thalassaemia, or HbSß+-thalassaemia) on a stable dose of hydroxyurea, hospitalised with vaso-occlusive crisis for parenteral opioid analgesia with a projected stay of more than 48 h were included in the study. Patients were randomly assigned (1:1) using a computer-generated randomisation scheme to receive sevuparin (18 mg/kg per day) or placebo (NaCl, 0·9% solution) intravenously for 2-7 days until vaso-occlusive crisis resolution. All individuals involved in the trial were masked to treatment allocation. The analysis was done in the intention-to-treat population. The primary endpoint was time to vaso-occlusive crisis resolution defined as freedom from parenteral opioid use (in preceding 6-10 h); and readiness for discharge as judged by the patient or physician. The trial is registered with ClinicalTrials.gov, NCT02515838. FINDINGS: Between Oct 7, 2015, and Feb 10, 2019, 144 patients were randomly assigned and administered sevuparin (n=69) or placebo (n=75). The median age was 22·2 years (range 12·2-33·6), 104 (72%) 144 were adults (18 years or older), and 90 (63%) were male and 54 (37%) were female. The intention-to-treat analysis for the primary endpoint showed no significant difference in median time to vaso-occlusive crisis resolution between the sevuparin and placebo groups (100·4 h [95% CI 85·5-116·8]) vs 86·4 h [70·6-95·1]; hazard ratio 0·89 [0·6-1·3]; p=0·55). Serious adverse events occurred in 16 (22%) of 68 patients in the sevuparin group and in 21 (22%) of patients in the placebo group. The most frequent treatment-emergent adverse events were pyrexia (17 [25%] in the sevuparin group vs 17 [22%] in the placebo group), constipation (12 [18%] vs 17 [22%]), and decreased haemoglobin (18 [26%] vs 9 [12%]). There were no deaths in the sevuparin group and there was one (1%) death in the placebo group after a hyper-haemolytic episode due to alloimmunisation. INTERPRETATION: This result, as well as the results seen in other clinical studies of inhibitors of adhesion in sickle cell disease, suggest that selectin-mediated adhesion might be important in the initiation, but not maintenance of vaso-occlusion, indicating that strategies to treat vaso-occlusive crises differ from strategies to prevent this complication. FUNDING: Modus Therapeutics.


Assuntos
Dor Aguda/tratamento farmacológico , Anemia Falciforme/patologia , Heparina/análogos & derivados , Dor Aguda/complicações , Adolescente , Adulto , Anemia Falciforme/complicações , Criança , Feminino , Febre/etiologia , Hemoglobinas/análise , Heparina/efeitos adversos , Heparina/uso terapêutico , Humanos , Masculino , Tempo de Tromboplastina Parcial , Efeito Placebo , Modelos de Riscos Proporcionais , Resultado do Tratamento , Adulto Jovem
2.
Ann Intern Med ; 172(2): 86-95, 2020 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-31887743

RESUMO

Background: MIV-711 is a novel selective cathepsin K inhibitor with beneficial effects on bone and cartilage in preclinical osteoarthritis models. Objective: To evaluate the efficacy, safety, and tolerability of MIV-711 in participants with symptomatic, radiographic knee osteoarthritis. Design: 26-week randomized, double-blind, placebo-controlled phase 2a study with a 26-week open-label safety extension substudy. (EudraCT: 2015-003230-26 and 2016-001096-73). Setting: Six European sites. Participants: 244 participants with primary knee osteoarthritis, Kellgren-Lawrence grade 2 or 3, and pain score of 4 to 10 on a numerical rating scale (NRS). Intervention: MIV-711, 100 (n = 82) or 200 (n = 81) mg daily, or matched placebo (n = 77). Participants (46 who initially received 200 mg/d and 4 who received placebo) received 200 mg of MIV-711 daily during the extension substudy. Measurements: The primary outcome was change in NRS pain score. The key secondary outcome was change in bone area on magnetic resonance imaging (MRI). Other secondary end points included cartilage thickness on quantitative MRI and type I and II collagen C-telopeptide biomarkers. Outcomes were assessed over 26 weeks. Results: Changes in NRS pain scores with MIV-711 were not statistically significant (placebo, -1.4; MIV-711, 100 mg/d, -1.7; MIV-711, 200 mg/d, -1.5). MIV-711 significantly reduced medial femoral bone area progression (P = 0.002 for 100 mg/d and 0.004 for 200 mg/d) and medial femoral cartilage thinning (P = 0.023 for 100 mg/d and 0.125 for 200 mg/d) versus placebo and substantially reduced bone and cartilage biomarker levels. Nine serious adverse events occurred in 6 participants (1 in the placebo group, 3 in the 100 mg group, and 2 in the 200 mg group); none were considered to be treatment-related. Limitation: The trial was relatively short. Conclusion: MIV-711 was not more effective than placebo for pain, but it significantly reduced bone and cartilage progression with a reassuring safety profile. This treatment may merit further evaluation as a disease-modifying osteoarthritis drug. Primary Funding Source: Medivir.


Assuntos
Catepsina K/antagonistas & inibidores , Compostos Orgânicos/uso terapêutico , Osteoartrite do Joelho/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Método Duplo-Cego , Europa (Continente) , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Osteoartrite do Joelho/diagnóstico por imagem , Medição da Dor
3.
Psychopharmacology (Berl) ; 231(6): 1251-65, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23640072

RESUMO

RATIONALE: Stimulation of nicotinic cholinergic systems has been shown to alleviate ADHD symptoms and to improve cognitive performance. AZD1446 is a selective α4ß2* nicotinic acetylcholine receptor agonist with potential effect on the symptoms of ADHD. OBJECTIVES: The purpose of this study is to evaluate the efficacy, safety, and pharmacokinetics of AZD1446 in adults with ADHD treated for 2 weeks. METHOD: This was a randomized, double-blind, placebo-controlled crossover trial. Participants were 79 adults with ADHD, grouped according to their use of nicotine-containing products. Nicotine non-users received placebo and two of three AZD1446 treatment regimens (80 mg tid, 80 mg qd, 10 mg tid). Nicotine users received placebo, AZD1446 80 mg tid and 80 mg qd. Efficacy measures included the Conners' Adult ADHD Rating Scale and cognitive measures of immediate and delayed verbal episodic memory, learning, attention, working memory, executive functioning, and spatial problem solving (CogState computerized test battery). RESULTS: There was no significant effect of AZD1446 on any of the clinical scores irrespective of dose, schedule, or concomitant use of nicotine products. A statistically significant improvement was seen on the Groton Maze Learning Task, a measure of executive functioning, in nicotine non-users after treatment with AZD1446 80 mg qd. CONCLUSIONS: AZD1446 was well tolerated, but did not significantly improve ADHD symptoms after 2 weeks of treatment compared to placebo. While the present study does not support the therapeutic utility of AZD1446 in ADHD, its potential pro-cognitive effects remain to be explored in other neuropsychiatric disorders.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Compostos Bicíclicos Heterocíclicos com Pontes/uso terapêutico , Agonistas Nicotínicos/uso terapêutico , Adulto , Transtorno do Deficit de Atenção com Hiperatividade/sangue , Transtorno do Deficit de Atenção com Hiperatividade/complicações , Compostos Bicíclicos Heterocíclicos com Pontes/efeitos adversos , Compostos Bicíclicos Heterocíclicos com Pontes/farmacocinética , Cognição/efeitos dos fármacos , Estudos Cross-Over , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Agonistas Nicotínicos/efeitos adversos , Agonistas Nicotínicos/farmacocinética , Escalas de Graduação Psiquiátrica , Receptores Nicotínicos/metabolismo , Fatores de Tempo , Tabagismo/sangue , Tabagismo/complicações , Resultado do Tratamento , Adulto Jovem
4.
Clin Pharmacol Drug Dev ; 3(1): 63-71, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27128232

RESUMO

AZD1446 is a highly selective agonist of central α4ß2 and α2ß2 neuronal nicotinic receptors. The compound has been shown to improve cognition in preclinical studies and thus has potential for treatment of cognitive disorders, including Alzheimer's disease (AD). This report presents the pharmacokinetics of AZD1446 based on a pooled population pharmacokinetic analysis of five studies in Caucasian and Japanese healthy volunteers. The model described the inter-individual and inter-occasion variability as well as identified the impact of covariates such as age and ethnicity on the parameters. Single doses of AZD1446 ranged between 0.5 and 350 mg and the multiple-dose regimens ranged between 10 and 100 mg four times daily. The maximum duration was 4 weeks. AZD1446 exhibited modest variability in CL/F. Compared with Caucasian subjects, Japanese subjects had approximately 25% higher rate of absorption and higher renal clearance as well as volume of distribution, resulting in a similar half-life. Compared with elderly subjects, young subjects had approximately 25% lower rate of absorption. Due to lower creatinine clearance, renal clearance was lower in elderly subjects. AZD1446 was safe and well tolerated, with nausea, headache and dizziness as the most frequently reported adverse events.

5.
Anticancer Res ; 30(1): 261-3, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20150645

RESUMO

A case of massive fundic gland polyposis (MFGPsis) in a female patient receiving protracted proton-pump inhibitor (PPI) medication is described. At gross examination the majority of the polyps were overlapping, confluent, some of them having a "cauliflower-like" configuration. The fundic gland polyps (FGP) arose in the gastric acid secretory mucosa. The confluence of these polyps impeded their enumeration. The gross and histological characteristics of this case seemed to be at variance with syndromic or sporadic cases having multiple FGP, inasmuch as in this case, the FGP had a propensity to agglutinate, to overlap and to develop confluent macrocysts. Another difference was that this disease, refractory to antacid treatment, required surgical intervention. This case substantiates the notion that protracted PPI medication may encourage the development of MFGPsis in susceptible individuals.


Assuntos
Fundo Gástrico/efeitos dos fármacos , Pólipos/induzido quimicamente , Inibidores da Bomba de Prótons/efeitos adversos , Gastropatias/induzido quimicamente , Feminino , Fundo Gástrico/patologia , Humanos , Pessoa de Meia-Idade , Pólipos/patologia , Gastropatias/patologia
6.
Eur J Cancer ; 43(7): 1153-60, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17398088

RESUMO

AIM: To assess the efficacy and safety of epirubicin, capecitabine and cisplatin (EXC) combination therapy in locally advanced breast cancer (LABC) and investigate the predictive value of selected biomarkers. METHODS: Newly diagnosed LABC patients received four 3-weekly cycles of neoadjuvant EXC (epirubicin 60 mg/m(2) day 1; capecitabine 1000 mg/m(2) bid, days 1-14; cisplatin 60 mg/m(2)day 1) and two cycles of post-operative EXC. RESULTS: Eight (17%) of 48 patients had inflammatory breast cancer. Overall response rate was 74% (95% CI: 59-86%), including complete responses in 13% (95% CI: 5-26%). Nine (22%; 95% CI: 11-38%) of 41 patients undergoing surgery achieved pathologic complete response (pCR), giving a pCR rate of 19% (95% CI: 9-33%) in the intent-to-treat population. Haematological toxicity was manageable. The most problematic toxicities were chemotherapy-induced nausea/vomiting and hypercoagulative disorders. None of the biomarkers investigated, including HER2, predicted response. CONCLUSION: EXC showed high efficacy in LABC, with high clinical response and pCR rate. Nausea and vomiting were unexpectedly frequent, and more aggressive prophylaxis and management of these side effects is recommended in future studies of this combination.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Adulto , Idoso , Antieméticos/uso terapêutico , Biomarcadores Tumorais/sangue , Neoplasias da Mama/cirurgia , Capecitabina , Quimioterapia Adjuvante , Cisplatino/administração & dosagem , Cisplatino/efeitos adversos , Desoxicitidina/administração & dosagem , Desoxicitidina/efeitos adversos , Desoxicitidina/análogos & derivados , Relação Dose-Resposta a Droga , Epirubicina/administração & dosagem , Epirubicina/efeitos adversos , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/efeitos adversos , Fluoruracila/análogos & derivados , Humanos , Infusões Intravenosas , Injeções Intravenosas , Mastectomia Radical , Pessoa de Meia-Idade , Terapia Neoadjuvante , Análise de Sobrevida , Resultado do Tratamento
7.
BMC Med ; 4: 16, 2006 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-16813654

RESUMO

BACKGROUND: Postmenopausal hormone-replacement therapy (HRT) increases breast-cancer risk. The influence of HRT on the biology of the primary tumor, however, is not well understood. METHODS: We obtained breast-cancer gene expression profiles using Affymetrix human genome U133A arrays. We examined the relationship between HRT-regulated gene profiles, tumor characteristics, and recurrence-free survival in 72 postmenopausal women. RESULTS: HRT use in patients with estrogen receptor (ER) protein positive tumors (n = 72) was associated with an altered regulation of 276 genes. Expression profiles based on these genes clustered ER-positive tumors into two molecular subclasses, one of which was associated with HRT use and had significantly better recurrence free survival despite lower ER levels. A comparison with external data suggested that gene regulation in tumors associated with HRT was negatively correlated with gene regulation induced by short-term estrogen exposure, but positively correlated with the effect of tamoxifen. CONCLUSION: Our findings suggest that post-menopausal HRT use is associated with a distinct gene expression profile related to better recurrence-free survival and lower ER protein levels. Tentatively, HRT-associated gene expression in tumors resembles the effect of tamoxifen exposure on MCF-7 cells.


Assuntos
Neoplasias da Mama/genética , Terapia de Reposição de Estrogênios , Perfilação da Expressão Gênica , Receptores de Estrogênio/análise , Receptores de Progesterona/análise , Neoplasias da Mama/classificação , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Estudos de Coortes , Primers do DNA , Intervalo Livre de Doença , Feminino , Humanos , Pós-Menopausa , Pré-Menopausa , Análise de Sobrevida , Transcrição Gênica
8.
Eur J Cancer ; 42(8): 1104-12, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16603346

RESUMO

The aim of this study was to investigate the expression of activated (phosphorylated) ERK1/2, oestrogen receptor alpha phosphorylated at S118 (ERalphaS118), and HER2 in primary breast cancer, and to make correlations with the outcome of tamoxifen therapy. We performed immunohistochemical analysis to determine the expression of HER2, ERalphaS118, and activated ERK1/2 in tumours obtained from 279 women with primary breast cancer. HER2 status was also estimated by fluorescence in situ hybridisation. We identified 108 women with ERalpha-positive tumours who had received adjuvant tamoxifen. Activated ERK1/2 (pERK1/2) and ERalphaS118 were found to be associated with each other and with other factors correlated with good prognosis. HER2 was inversely associated with pERK1/2. Positive staining for pERK1/2 (particularly intense staining) indicated better relapse-free survival (P=0.05) and a trend towards better breast cancer-corrected survival in women treated with tamoxifen. To conclude, this study shows that activated ERK1/2 and ERalphaS118 are associated with improved survival. The poorer outcome in HER2-positive women who receive adjuvant tamoxifen cannot be explained by the crosstalk between HER2 and ERalphaS118 via activated ERK1/2 alone.


Assuntos
Antineoplásicos Hormonais/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Receptor alfa de Estrogênio/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Tamoxifeno/uso terapêutico , Adulto , Idoso , Neoplasias da Mama/mortalidade , Feminino , Humanos , Hibridização in Situ Fluorescente , Pessoa de Meia-Idade , Fosforilação , Receptor ErbB-2/metabolismo , Análise de Sobrevida
9.
J Biol Chem ; 281(10): 6776-84, 2006 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-16407243

RESUMO

Increased levels of the inflammatory mediator leukotriene D4 (LTD4) are present at sites of inflammatory bowel disease, and such areas also exhibit an increased risk for subsequent cancer development. It is known that LTD4 affects the expression of many proteins that influence survival and proliferation of intestinal epithelial cells. We demonstrate here that after LTD4 exposure, beta-catenin translocates to the nucleus where it signals activation of the TCF/LEF family of transcription factors. These events are mediated via a phosphatidylinositol 3-kinase-dependent phosphorylation of the inhibitory Ser-9 residue of glycogen synthase kinase 3beta. We also show that in the presence of LTD4, free beta-catenin translocates to the mitochondria where it associates with the cell survival protein Bcl-2. We hypothesize that LTD4 may enhance cell survival via activation of beta-catenin signaling, in particular, by promoting the association of beta-catenin with Bcl-2 in the mitochondria. Similar to Wnt-1 signaling, LTD4 signals an increased level of free beta-catenin and elevated TCF/LEF promotor activity. This work in intestinal epithelial cells further lends credence to the idea that inflammatory signaling pathways are intrinsically linked with potential oncogenic signals involved in cell survival and apoptosis.


Assuntos
Apoptose/fisiologia , Leucotrieno D4/fisiologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Transdução de Sinais/fisiologia , beta Catenina/metabolismo , Linhagem Celular , Sobrevivência Celular , Transformação Celular Neoplásica/metabolismo , Quinase 3 da Glicogênio Sintase/metabolismo , Glicogênio Sintase Quinase 3 beta , Humanos , Mucosa Intestinal/enzimologia , Mucosa Intestinal/metabolismo , Microscopia de Fluorescência , Mitocôndrias/metabolismo , Transporte Proteico , Proteínas Proto-Oncogênicas c-bcl-2/genética , Fatores de Transcrição TCF/biossíntese , Fatores de Transcrição TCF/genética , beta Catenina/genética
10.
J Gen Virol ; 86(Pt 6): 1695-1702, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15914847

RESUMO

The aim of this study was to identify recurrent respiratory papillomatosis patients who may benefit from interferon (IFN)-alpha treatment and to determine the means of IFN-alpha action. The presence of human papillomavirus (HPV) and viral load and proliferation rate in pre-, ongoing and post-treatment respiratory papillomatosis biopsies were examined retrospectively in 25 patients, 18 of whom were IFN-alpha treated and seven of whom were IFN-alpha non-treated. Using PCR, HPV was found to be present in 20/25 respiratory papillomatosis patients and HPV type was determined for 18/25 patients (12 HPV6 and six HPV11). Eighteen of the patients were treated with IFN-alpha, 14 of whom were HPV positive (eight HPV6, five HPV11 and one undefined HPV). Response to IFN-alpha therapy was observed in 12 patients (7/8 HPV6, 3/5 HPV11, 1/1 undefined HPV and 1/4 HPV negative), while six patients (1/8 HPV6, 2/5 HPV11 and 3/4 HPV negative) did not respond to therapy. Viral load, determined by quantitative real-time PCR (between 0.03 and 533 HPV copies per cell), and proliferation rate, determined as the percentage of Ki-67-positive cells (between 8 and 54 %), were similar in IFN-alpha-treated and non-treated patients and were generally unaffected by IFN-alpha treatment. In summary, most (12/18) IFN-alpha-treated patients responded to therapy. Moreover, there was a tendency for patients with HPV6-positive (7/8) respiratory papillomatosis to respond more frequently to IFN-alpha therapy than patients with HPV11 (3/5) or HPV-negative (1/4) respiratory papillomatosis. Finally, the presence of HPV and viral load and proliferation in respiratory papillomatosis biopsies was similar in patients treated or not with IFN-alpha and were in general unaffected by IFN-alpha treatment.


Assuntos
Antivirais/uso terapêutico , Interferon-alfa/uso terapêutico , Recidiva Local de Neoplasia/tratamento farmacológico , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/tratamento farmacológico , Neoplasias do Sistema Respiratório/tratamento farmacológico , Adolescente , Adulto , Idoso , Biópsia , Criança , Pré-Escolar , DNA Viral/análise , Feminino , Finlândia , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/virologia , Papillomaviridae/genética , Infecções por Papillomavirus/virologia , Neoplasias do Sistema Respiratório/virologia , Estudos Retrospectivos , Suécia , Carga Viral
11.
Cancer Res ; 65(3): 732-42, 2005 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-15705869

RESUMO

Searching for a link between inflammation and colon cancer, we have found that the inflammatory mediator leukotriene D(4) (LTD(4)), via its receptor CysLT(1), induces cyclooxygenase-2 expression, survival, and proliferation in intestinal epithelial cells. In conjunction with our previous observation that CysLT(1) receptor expression is increased in colorectal adenocarcinomas, we here found an increased nuclear localization of the CysLT(1) receptor in colorectal adenocarcinomas. This novel discovery of CysLT(1) receptors in the nucleus was further analyzed. It was found to be located in the outer nuclear membrane in colon cancer cells and in the nontransformed epithelial cell line Int 407 cells by Western blot and electron microscopy. Cancer cells displayed higher amounts of the nuclear CysLT(1) receptor, but prolonged LTD(4) exposure induced its nuclear translocation in nontransformed cells. Truncation of a nuclear localization sequence abrogated this translocation as well as the LTD(4)-induced proliferative response. In accordance, nuclear CysLT(1) receptors exhibited proliferative extracellular signal-regulated kinase 1/2 signaling. The significance of these experimental findings is supported by the observed correlation between the proliferative marker Ki-67 and nuclear CysLT(1) receptor localization in colorectal adenocarcinomas. The present findings indicate that LTD(4) cannot only be synthesized but also signal proliferation through nuclear CysLT(1) receptors, stressing the importance of leukotrienes in inflammation-induced colon carcinogenesis.


Assuntos
Adenocarcinoma/metabolismo , Neoplasias Colorretais/metabolismo , Proteínas de Membrana/metabolismo , Sinais de Localização Nuclear/metabolismo , Receptores de Leucotrienos/metabolismo , Adenocarcinoma/enzimologia , Adenocarcinoma/genética , Sequência de Aminoácidos , Araquidonato 5-Lipoxigenase/metabolismo , Células CACO-2 , Linhagem Celular Tumoral , Membrana Celular/enzimologia , Membrana Celular/metabolismo , Núcleo Celular/enzimologia , Núcleo Celular/metabolismo , Neoplasias Colorretais/enzimologia , Neoplasias Colorretais/genética , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Regulação Neoplásica da Expressão Gênica , Humanos , Leucotrieno D4/farmacologia , Proteínas de Membrana/biossíntese , Proteínas de Membrana/genética , Dados de Sequência Molecular , Receptores de Leucotrienos/biossíntese , Receptores de Leucotrienos/genética , Regulação para Cima
13.
Biochem Biophys Res Commun ; 302(2): 330-5, 2003 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-12604350

RESUMO

Leukotrienes play an important pathophysiological role in chronic inflammatory states and, as previously shown, cause increased levels of cyclooxygenase-2 (COX-2) in intestinal epithelial cells. The anti-apoptotic protein Bcl-2 is also elevated by LTD(4) stimulation, and in colon cancer, so we studied the mechanisms of COX-2 and Bcl-2 regulation. We found that LTD(4) induced a 3-fold elevation of COX-2 transcription in Int 407 cells and a 2-fold equivalent in colon cancer cells, Caco-2. This was mediated through a pertussis toxin (PTX) sensitive G-protein and the MAP kinase Erk-1/2 pathway, and this was also shown to be the route to up-regulation of Bcl-2 by LTD(4). In good agreement with this, we detected a strong activation of Erk-1/2 that was further increased by COX-2 inhibition, pointing towards the existence of negative feedback regulation. Furthermore, COX-2 activity is responsible for the effects on Bcl-2, but this is not conveyed through the production of PGE(2).


Assuntos
Isoenzimas/biossíntese , Leucotrienos/farmacologia , Prostaglandina-Endoperóxido Sintases/biossíntese , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Transdução de Sinais/fisiologia , Células CACO-2 , Ciclo-Oxigenase 2 , Interações Medicamentosas , Ativação Enzimática/efeitos dos fármacos , Indução Enzimática/efeitos dos fármacos , Humanos , Isoenzimas/genética , MAP Quinase Quinase 1 , Proteínas de Membrana , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Toxina Pertussis/farmacologia , Prostaglandina-Endoperóxido Sintases/genética , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/genética , Transcrição Gênica/efeitos dos fármacos , Regulação para Cima
14.
Gastroenterology ; 124(1): 57-70, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12512030

RESUMO

BACKGROUND & AIMS: The effects of leukotriene (LT) D(4) on intestinal epithelial cells govern events that are involved in cell survival and colon cancer, notably increased expression of cyclooxygenase (COX)-2 and enhanced production of prostaglandin E(2). We investigated possible correlations between distribution of the recently described LTD(4) receptor CysLT(1)R and factors previously shown to be up-regulated by LTD(4) as well as clinicopathologic traits. METHODS: Immunohistochemistry and in situ hybridization were performed on tissue arrays, which were made using colorectal cancer samples from 84 patients. RESULTS: CysLT(1)R was significantly correlated to COX-2, 5-lipoxygenase, and Bcl-x(L). Male subjects more often exhibited high levels of this receptor relative to female subjects, and Dukes' B patients with elevated CysLT(1)R expression showed markedly poorer survival than those with low-level expression. Furthermore, this was paralleled by an increased viability of CysLT(1)R-overexpressing cells in a colon cancer cell line. CONCLUSIONS: Our results further implicate the involvement of LTs in colorectal carcinoma. Based on our present and earlier findings, we propose that LT/CysLT(1)R signaling facilitates survival of colon cancer cells, which may affect disease outcome. Like COX-2, LTs are accessible targets for pharmacologic treatment.


Assuntos
Adenocarcinoma/metabolismo , Neoplasias Colorretais/metabolismo , Isoenzimas/metabolismo , Proteínas de Membrana , Prostaglandina-Endoperóxido Sintases/metabolismo , Receptores de Leucotrienos/metabolismo , Adenocarcinoma/patologia , Idoso , Idoso de 80 Anos ou mais , Sobrevivência Celular/fisiologia , Neoplasias Colorretais/patologia , Ciclo-Oxigenase 2 , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Análise de Sobrevida , Células Tumorais Cultivadas
15.
Adv Exp Med Biol ; 507: 193-8, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12664585

RESUMO

In this preliminary report we present data showing that leukotrienes increase the baseline cell viability in human intestinal epithelial cells and that LTB4 partially reverses the morphological hallmarks of non-necrotic cell death induced by the COX-2 specific inhibitor NS-398. The proposed signaling mechanisms regulating these events are summarized in fig. 3. Please view the work on LT signal transduction in these cells by Thodeti et al. in this volume.


Assuntos
Sobrevivência Celular/fisiologia , Mucosa Intestinal/citologia , Leucotrienos/fisiologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Inibidores de Ciclo-Oxigenase/farmacologia , Humanos , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/fisiologia , Nitrobenzenos/farmacologia , Sulfonamidas/farmacologia
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