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1.
Ann Oncol ; 33(7): 685-692, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35395383

RESUMO

BACKGROUND: Sarcopenia represents an established adverse prognostic factor in cancer patients. Consequently, different means to counteract sarcopenia have been proposed to improve cancer treatment. Computed tomography (CT)-based measurements, also labor intensive, are well validated for the analysis of sarcopenia. As inflammation plays a key role in the development of sarcopenia, we here studied the role of the modified Glasgow prognostic score (mGPS), consisting of inflammation parameters plasma C-reactive protein (CRP) and albumin, to predicting sarcopenia and adipose tissue-related body composition (BC) parameters at baseline and their changes during treatment and to analyze its prognostic role in conjunction with BC parameters. PATIENTS AND METHODS: CT measurements of BC parameters were carried out at baseline and week 12 in patients with advanced gastric or esophagogastric junction cancer from the phase III EXPAND trial, undergoing first-line platinum-fluoropyrimidine chemotherapy. mGPS was calculated from baseline CRP and albumin plasma levels. Pearson correlation and Cox regression analyses were carried out. RESULTS: mGPS is strongly prognostic for overall survival (OS). Baseline mGPS is significantly correlated with baseline mean muscle attenuation (MA; P < 0.0001). Baseline mGPS did not predict a decline in muscle or adipose tissue parameters during 12 weeks of treatment and a decline in muscle or adipose tissue parameters was not prognostic for OS. MA lost its prognostic role for OS when mGPS or CRP was entered into the Cox models. Eastern Cooperative Oncology Group performance status together with CRP or mGPS remained the sole baseline prognostic factors for OS. CONCLUSIONS: Our findings support a model where tumor-mediated inflammatory response represents a strong prognostic factor, which is causally related to sarcopenia, but with no direct causal path from sarcopenia to survival. Therefore, therapeutic targeting of systemic inflammation should be further explored as a promising strategy to improve both sarcopenia and the efficacy and tolerability of cancer treatment.


Assuntos
Neoplasias , Sarcopenia , Albuminas , Composição Corporal , Junção Esofagogástrica , Humanos , Inflamação , Prognóstico , Estudos Retrospectivos
2.
Hum Gene Ther ; 30(10): 1284-1296, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31407607

RESUMO

Endothelial cells (EC) are targets in gene therapy and regenerative medicine, but they are inefficiently transduced with adeno-associated virus (AAV) vectors of various serotypes. To identify barriers hampering efficient transduction and to develop an optimized AAV variant for EC transduction, we screened an AAV serotype 2-based peptide display library on primary human macrovascular EC. Using a new high-throughput selection and monitoring protocol, we identified a capsid variant, AAV-VEC, which outperformed the parental serotype as well as first-generation targeting vectors in EC transduction. AAV vector uptake was improved, resulting in significantly higher transgene expression levels from single-stranded vector genomes detectable within a few hours post-transduction. Notably, AAV-VEC transduced not only proliferating EC but also quiescent EC, although higher particle-per-cell ratios had to be applied. Also, induced pluripotent stem cell-derived endothelial progenitor cells, a novel tool in regenerative medicine and gene therapy, were highly susceptible toward AAV-VEC transduction. Thus, overcoming barriers by capsid engineering significantly expands the AAV tool kit for a wide range of applications targeting EC.


Assuntos
Capsídeo/química , Dependovirus/genética , Engenharia Genética/métodos , Vetores Genéticos/química , Células Endoteliais da Veia Umbilical Humana/metabolismo , Transdução Genética/métodos , Sequência de Aminoácidos , Capsídeo/metabolismo , Diferenciação Celular , Dependovirus/metabolismo , Genes Reporter , Terapia Genética/métodos , Vetores Genéticos/metabolismo , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Células HEK293 , Células HeLa , Células Endoteliais da Veia Umbilical Humana/citologia , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Biblioteca de Peptídeos
3.
Br J Cancer ; 116(5): 600-608, 2017 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-28141797

RESUMO

BACKGROUND: Vascular endothelial growth factor (VEGF)-targeting drugs normalise the tumour vasculature and improve access for chemotherapy. However, excessive VEGF inhibition fails to improve clinical outcome, and successive treatment cycles lead to incremental extracellular matrix (ECM) deposition, which limits perfusion and drug delivery. We show here, that low-dose VEGF inhibition augmented with PDGF-R inhibition leads to superior vascular normalisation without incremental ECM deposition thus maintaining access for therapy. METHODS: Collagen IV expression was analysed in response to VEGF inhibition in liver metastasis of colorectal cancer (CRC) patients, in syngeneic (Panc02) and xenograft tumours of human colorectal cancer cells (LS174T). The xenograft tumours were treated with low (0.5 mg kg-1 body weight) or high (5 mg kg-1 body weight) doses of the anti-VEGF antibody bevacizumab with or without the tyrosine kinase inhibitor imatinib. Changes in tumour growth, and vascular parameters, including microvessel density, pericyte coverage, leakiness, hypoxia, perfusion, fraction of vessels with an open lumen, and type IV collagen deposition were compared. RESULTS: ECM deposition was increased after standard VEGF inhibition in patients and tumour models. In contrast, treatment with low-dose bevacizumab and imatinib produced similar growth inhibition without inducing detrimental collagen IV deposition, leading to superior vascular normalisation, reduced leakiness, improved oxygenation, more open vessels that permit perfusion and access for therapy. CONCLUSIONS: Low-dose bevacizumab augmented by imatinib selects a mature, highly normalised and well perfused tumour vasculature without inducing incremental ECM deposition that normally limits the effectiveness of VEGF targeting drugs.


Assuntos
Bevacizumab/administração & dosagem , Neoplasias Colorretais/tratamento farmacológico , Mesilato de Imatinib/administração & dosagem , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/secundário , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Bevacizumab/farmacologia , Linhagem Celular Tumoral , Colágeno Tipo IV/metabolismo , Matriz Extracelular/efeitos dos fármacos , Humanos , Mesilato de Imatinib/farmacologia , Camundongos , Resultado do Tratamento , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Gastroenterol Res Pract ; 2016: 9189483, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27656206

RESUMO

Background. In metastatic colorectal cancer (mCRC), continuing antiangiogenic drugs beyond progression might provide clinical benefit. We synthesized the available evidence in a meta-analysis. Patients and Methods. We conducted a meta-analysis of studies investigating the use of antiangiogenic drugs beyond progression. Eligible studies were randomized phase II/III trials. Primary endpoints were overall survival (OS) and progression-free survival (PFS). Secondary endpoints were the impact of continuing antiangiogenic drugs (i) in subgroups, (ii) in different types of compounds targeting the VEGF-axis (monoclonal antibodies versus tyrosine kinase inhibitors), and (iii) on remission rates and prevention of progression. Results. Eight studies (3,668 patients) were included. Continuing antiangiogenic treatment beyond progression significantly improved PFS (HR 0.64; 95%-CI, 0.55-0.75) and OS (HR 0.83; 95%-CI, 0.76-0.89). PFS was significantly improved in all subgroups with comparable HR. OS was improved in all subgroups stratified by age, gender, and ECOG status. The rate of patients achieving at least stable disease was improved with an OR of 2.25 (95%-CI, 1.41-3.58). Conclusions. This analysis shows a significant PFS and OS benefit as well as a benefit regarding disease stabilization when using antiangiogenic drugs beyond progression in mCRC. Future studies should focus on the optimal sequence of administering antiangiogenic drugs.

5.
Adv Exp Med Biol ; 917: 261-85, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27236560

RESUMO

Angiogenesis plays a pivotal role in malignant, ischemic, inflammatory, infectious and immune disorders. The increasing molecular understanding of angiogenic processes fostered the development of strategies to induce or inhibit angiogenesis for therapeutic purposes. Here, we focus on anti-angiogenic therapies, which represent a standard of care in the treatment of different cancer types and in neovascular age-related macular degeneration. Specifically, strategies related to the blockade of angiogenic proteins and receptors will be outlined covering both preclinical and clinical aspects. Finally, examples of gene therapy based anti-angiogenic approaches are presented.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Neoplasias/tratamento farmacológico , Neovascularização Patológica/prevenção & controle , Degeneração Macular Exsudativa/tratamento farmacológico , Animais , Humanos , Neoplasias/irrigação sanguínea
6.
Br J Cancer ; 112(3): 495-503, 2015 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-25562438

RESUMO

BACKGROUND: Effective vascular normalisation following vascular endothelial growth factor (VEGF) inhibition is associated with endothelial cell regression leaving empty basement membrane sleeves (BMS). These long-lived BMS permit the rapid regrowth of tumour vasculature upon treatment cessation and promote resistance to VEGF-targeting drugs. Previous attempts at removing BMS have failed. Angiopoietin-2 (Ang2) is a vascular destabilizing factor that antagonises normalisation. We hypothesised that Ang2 inhibition could permit vascular normalisation at significantly reduced doses of VEGF inhibition, avoiding excessive vessel regression and the formation of empty BMS. METHODS: Mice xenografted with human colorectal cancer cells (LS174T) were treated with low (0.5 mg kg(-1)) or high (5 mg kg(-1)) doses of the VEGF-targeting antibody bevacizumab with or without an Ang2 blocking peptibody L1-10. Tumour growth, BMS formation and normalisation parameters were examined including vessel density, pericyte coverage, adherence junctions, leakiness, perfusion, hypoxia and proliferation. RESULTS: Dual targeting of VEGF and Ang2 achieved effective normalisation at only one-tenth of the dose required with bevacizumab alone. Pericyte coverage, vascular integrity, adherence junctions and perfusion as prerequisites for improved access of chemotherapy were improved without inducing empty BMS that facilitate rapid vascular regrowth. CONCLUSIONS: Dual targeting of VEGF and Ang2 can potentiate the effectiveness of VEGF inhibitors and avoid the formation of empty BMS.


Assuntos
Angiopoietina-2/antagonistas & inibidores , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Membrana Basal/efeitos dos fármacos , Neoplasias do Colo/tratamento farmacológico , Neovascularização Patológica/prevenção & controle , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Animais , Anticorpos Monoclonais Humanizados/administração & dosagem , Membrana Basal/patologia , Bevacizumab , Vasos Sanguíneos/efeitos dos fármacos , Vasos Sanguíneos/patologia , Neoplasias do Colo/irrigação sanguínea , Neoplasias do Colo/patologia , Sinergismo Farmacológico , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Terapia de Alvo Molecular/métodos , Proteínas Recombinantes de Fusão/administração & dosagem , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Br J Cancer ; 109(6): 1408-13, 2013 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-23963139

RESUMO

BACKGROUND: Combined inhibition of platelet-derived growth factor receptor beta signalling and vascular endothelial growth factor promotes vascular normalisation in preclinical models and may lead to increased delivery of chemotherapy to tumour tissue. This phase I/II trial assessed the safety and efficacy of capecitabine plus oxaliplatin (XELOX) plus bevacizumab and imatinib in the first-line treatment of patients with metastatic colorectal cancer. METHODS: Two dose levels (I/II) were defined: capecitabine 850/1000 mg m(-2) twice daily on days 1-14; oxaliplatin 100/130 mg m(-2) on day 1; bevacizumab 7.5 mg kg(-1) on day 1; imatinib 300 mg day(-1) on days 1-21 every 21 days. The primary study endpoint was safety. The phase II secondary endpoint was 6-month progression-free survival (PFS). RESULTS: Dose level I was chosen for phase II testing because, even though further dose escalation was permitted by the protocol, gastrointestinal toxicities were considered to be clinically significant. A total of 49 patients were evaluated. The 6-month PFS rate was 76%, median PFS was 10.6 months and median overall survival was 23.2 months. Haematological toxicities were generally mild. Sensory neuropathy and diarrhoea were the most common grade 3 toxicities. CONCLUSION: The combination of XELOX with bevacizumab and imatinib is tolerable and has promising efficacy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/efeitos adversos , Benzamidas/administração & dosagem , Benzamidas/efeitos adversos , Bevacizumab , Capecitabina , Neoplasias Colorretais/patologia , Desoxicitidina/administração & dosagem , Desoxicitidina/efeitos adversos , Desoxicitidina/análogos & derivados , Intervalo Livre de Doença , Esquema de Medicação , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/efeitos adversos , Fluoruracila/análogos & derivados , Humanos , Mesilato de Imatinib , Masculino , Pessoa de Meia-Idade , Compostos Organoplatínicos/administração & dosagem , Compostos Organoplatínicos/efeitos adversos , Oxaliplatina , Piperazinas/administração & dosagem , Piperazinas/efeitos adversos , Estudos Prospectivos , Pirimidinas/administração & dosagem , Pirimidinas/efeitos adversos , Resultado do Tratamento
8.
Ann Oncol ; 24(6): 1560-7, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23493136

RESUMO

BACKGROUND: Metastatic colorectal cancer (mCRC) is commonly treated with 5-fluorouracil, folinic acid, and oxaliplatin or irinotecan. The multitargeted kinase inhibitor, regorafenib, was combined with chemotherapy as first- or second-line treatment of mCRC to assess safety and pharmacokinetics (primary objectives) and tumor response (secondary objective). PATIENTS AND METHODS: Forty-five patients were treated every 2 weeks with 5-fluorouracil 400 mg/m(2) bolus then 2400 mg/m(2) over 46 h, folinic acid 400 mg/m(2), and either oxaliplatin 85 mg/m(2) or irinotecan 180 mg/m(2). On days 4-10, patients received regorafenib 160 mg orally once daily. RESULTS: The median duration of treatment was 108 (range 2-345 days). Treatment was stopped for adverse events or death (17 patients), disease progression (11 patients), and consent withdrawal or investigator decision (11 patients). Six patients remained on regorafenib at data cutoff (two without chemotherapy). Drug-related adverse events occurred in 44 patients [grade ≥ 3 in 32 patients: mostly neutropenia (17 patients) and leukopenia, hand-foot skin reaction, and hypophosphatemia (four patients each)]. Thirty-three patients achieved disease control (partial response or stable disease) for a median of 126 (range 42-281 days). CONCLUSION: Regorafenib had acceptable tolerability in combination with chemotherapy, with increased exposure of irinotecan and SN-38 but no significant effect on 5-fluorouracil or oxaliplatin pharmacokinetics.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Camptotecina/administração & dosagem , Camptotecina/análogos & derivados , Camptotecina/farmacocinética , Neoplasias Colorretais/metabolismo , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/farmacocinética , Humanos , Leucovorina/administração & dosagem , Leucovorina/farmacocinética , Masculino , Pessoa de Meia-Idade , Compostos Organoplatínicos/administração & dosagem , Compostos Organoplatínicos/farmacocinética , Compostos de Fenilureia/administração & dosagem , Compostos de Fenilureia/farmacocinética , Piridinas/administração & dosagem , Piridinas/farmacocinética , Resultado do Tratamento , Adulto Jovem
9.
Dtsch Med Wochenschr ; 136(5): 179-81, 2011 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-21271476

RESUMO

In patients up to 70 years of age with colon carcinoma stage III adjuvant chemotherapy with infusions of fluorouracil (5-FU) or oral capecitabine combined with oxaliplatin should be the standard method. A new standard for the palliative treatment of Her2/newly positive advanced gastric cancer and cancer at the gastro-esophageal junction is the administration of trastuzumab combined with chemotherapy. Patients with high-risk soft tissue sarcoma can be helped, in addition to surgical resection and subsequent radiotherapy, by neoadjuvant chemotherapy combined with regional deep hyperthermia. For patients with lung cancer additional individualized treatment is about to become routine. In addition to the EGFR mutation status, all non-smokers should in future be tested for aberration in the anaplastic lymphoma kinase (ALK) gene.


Assuntos
Carcinoma Broncogênico/terapia , Neoplasias do Colo/terapia , Neoplasias Pulmonares/terapia , Sarcoma/terapia , Neoplasias de Tecidos Moles/terapia , Neoplasias Gástricas/terapia , Idoso , Quinase do Linfoma Anaplásico , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Broncogênico/genética , Carcinoma Broncogênico/patologia , Quimioterapia Adjuvante , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Terapia Combinada , Análise Mutacional de DNA , Receptores ErbB/genética , Testes Genéticos , Humanos , Hipertermia Induzida , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Terapia Neoadjuvante , Estadiamento de Neoplasias , Cuidados Paliativos , Proteínas Tirosina Quinases/genética , Radioterapia Adjuvante , Receptores Proteína Tirosina Quinases , Receptor ErbB-2/genética , Sarcoma/genética , Sarcoma/patologia , Neoplasias de Tecidos Moles/genética , Neoplasias de Tecidos Moles/patologia , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Trastuzumab
10.
Br J Cancer ; 103(9): 1407-14, 2010 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-20924372

RESUMO

BACKGROUND: The combination of chemotherapy with the vascular endothelial growth factor (VEGF) antibody bevacizumab is a standard of care in advanced colorectal cancer (CRC). However, biomarkers predicting outcome of bevacizumab-containing treatment are lacking. As angiopoietin-2 (Ang-2) is a key regulator of vascular remodelling in concert with VEGF, we investigated its role as a biomarker in metastatic CRC. METHODS: Serum Ang-2 levels were measured in 33 healthy volunteers and 90 patients with CRC. Of these, 34 had metastatic disease and received bevacizumab-containing therapy. To determine the tissue of origin of Ang-2, quantitative real-time PCR was performed on microdissected cryosections of human CRC and in a murine xenograft model of CRC using species-specific amplification. RESULTS: Ang-2 originated from the stromal compartment of CRC tissues. Serum Ang-2 levels were significantly elevated in patients with metastatic CRC compared with healthy controls. Amongst patients receiving bevacizumab-containing treatment, low pre-therapeutic serum Ang-2 levels were associated with a significant better response rate (82 vs 31%; P<0.01), a prolonged median progression-free survival (14.1 vs 8.5 months; P<0.01) and a reduction of 91% in the hazard of death (P<0.05). CONCLUSION: Serum Ang-2 is a candidate biomarker for outcome of patients with metastatic CRC treated with bevacizumab-containing therapy, and it should be further validated to customise combined chemotherapeutic and anti-angiogenic treatment.


Assuntos
Angiopoietina-2/sangue , Anticorpos Monoclonais/administração & dosagem , Neoplasias Colorretais/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Animais , Anticorpos Monoclonais Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Bevacizumab , Biomarcadores Tumorais/sangue , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/patologia , Feminino , Humanos , Masculino , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Prognóstico , Resultado do Tratamento , Fator A de Crescimento do Endotélio Vascular/administração & dosagem , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Clin Exp Immunol ; 125(3): 465-9, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11531955

RESUMO

The inflammatory response in infectious and autoimmune diseases is regulated by the balance between pro- and anti-inflammatory cytokines. The IL-1 complex contains polymorphic genes coding for IL-1alpha, IL-1beta and IL-1Ra. The IL-1Ra (variable number of tanden repeat) VNTR polymorphism has been shown to influence the capacity to produce IL-1beta and IL-1Ra after in vitro stimulation. Allele 2 of this polymorphism is associated with a number of inflammatory diseases. To determine the impact of the IL-1Ra polymorphism on in vivo human cytokine synthesis, we used a yellow fever vaccination model for the induction of cytokine synthesis in healthy volunteers. Two different yellow fever vaccines were used. After administration of the RKI vaccine (34 volunteers), plasma TNF-alpha concentration increased from 13.4 +/- 0.9 pg/ml to 23.3 +/- 1.1 pg/ml (P < 0.001), and plasma IL-1Ra concentration increased from 308 +/- 25 pg/ml to 1019 +/- 111 pg/ml (P < 0.001), on day 2. Using Stamaril vaccine, no increase in the plasma concentrations of either TNF-alpha or IL-1Ra could be detected (n = 17). Only the RKI vaccine induced TNF-alpha synthesis after in vitro stimulation of MNC. Carriers of allele 2 of the IL-1Ra polymorphism had increased baseline concentrations of IL-1Ra (350 +/- 32 pg/ml) compared with non-carriers (222 +/- 18 pg/ml, P < 0.001), and decreased concentrations of IL-1beta (0.9 +/- 0.2 pg/ml for carriers versus 2.8 +/- 0.7 pg/ml for non-carriers, P = 0.017). After yellow fever vaccination (RKI vaccine), no significant differences in the increase of IL-1Ra plasma levels were detected between carriers and non-carriers of allele 2 of the IL-1Ra gene polymorphism. This is the first study to examine the influence of this genetic polymorphism on in vivo-induced human IL-1beta and IL-1Ra synthesis. Baseline concentrations of IL-1Ra and IL-1beta were significantly influenced by the IL-1Ra polymorphism. No influence of the IL-1Ra polymorphism on the in vivo-induced production of IL-1Ra and IL-1beta could be detected.


Assuntos
Interleucina-1/sangue , Sialoglicoproteínas/sangue , Sialoglicoproteínas/genética , Vacina contra Febre Amarela/imunologia , Adolescente , Adulto , Heterozigoto , Humanos , Proteína Antagonista do Receptor de Interleucina 1 , Leucócitos Mononucleares/imunologia , Pessoa de Meia-Idade , Fator de Necrose Tumoral alfa/análise , Vacinação , Febre Amarela/imunologia , Febre Amarela/prevenção & controle
12.
Gene Ther ; 8(12): 966-8, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11426338

RESUMO

Recombinant adeno-associated virus type 2 (rAAV) is a promising vector for in vivo gene therapy. Transduction by rAAV requires binding to heparan sulfate proteoglycan on the cell surface, and heparin can block this binding. Because heparin is administered to most patients undergoing cardiovascular gene transfer in order to prevent thrombotic events, it is important to identify anticoagulants which do not interfere with rAAV transduction. Therefore, we examined the influence of different anticoagulants on rAAV transduction in vitro. rAAV transduction was inhibited by 40.5 +/- 7.9% at heparin concentrations of 0.1 U/ml, and by 81.7 +/- 3.6% at 1.0 U/ml. The low molecular weight (LMW) heparin tinzaparin inhibited rAAV transduction by 20.2 +/- 3.8% at 0.1 U/ml and 37.1 +/- 1.8% at 1.0 U/ml. The inhibitory effect was significantly weaker compared with heparin at 1.0 U/ml, (P < 0.01). The LMW heparinoid danaparoid inhibited rAAV transduction by 8.8 +/- 3.5% at 0.1 U/ml (P < 0.01 compared with heparin). In contrast, recombinant hirudin did not interfere at all with rAAV transduction. In summary, the results demonstrate that inhibition of rAAV transduction by heparin occurs rapidly and at therapeutically used concentrations. LMW heparinoids and above all recombinant hirudin might be alternatives for heparin when vascular gene transfer with rAAV requires transient anticoagulation.


Assuntos
Anticoagulantes/farmacologia , Dependovirus/genética , Vetores Genéticos/administração & dosagem , Células HeLa/efeitos dos fármacos , Heparina/farmacologia , Transdução Genética , Sulfatos de Condroitina/farmacologia , Dermatan Sulfato/farmacologia , Relação Dose-Resposta a Droga , Combinação de Medicamentos , Heparina de Baixo Peso Molecular/farmacologia , Heparitina Sulfato/farmacologia , Hirudinas/análogos & derivados , Hirudinas/farmacologia , Humanos , Proteínas Recombinantes/farmacologia , Tinzaparina
13.
Leuk Res ; 22(6): 501-7, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9678716

RESUMO

Tumor necrosis factor-alpha (TNF-alpha) and nitric oxide (NO) exert a wide array of immunoregulatory, partly related effects. We examined the production of these two mediators by the human hairy cell leukemia cell line Eskol. Combined cell lysate and supernatant of Eskol cells (0.5 x 10(6) cells ml(-1)) incubated for 18 h, contained a mean of 1.5 ng ml(-1) TNF-alpha. This spontaneous TNF-alpha synthesis was enhanced by phorbol ester (PMA) and phytohemagglutinin (PHA) and decreased by dexamethasone. Nitrite, the stable product of NO, accumulated in the supernatant of Eskol cells after prolonged incubation. Maximal nitrite concentrations (range: 0.8-3.5 microM at 2 x 10(6) cells ml(-1)) were detected after 7 days of incubation. NO production was augmented by PHA and reduced by PMA. The inhibitors of NO synthase N(G)-monomethyl-L-arginine (L-NMMA) and aminoguanidine decreased NO synthesis. Simultaneous activation with the proinflammatory cytokines, interferon-gamma, interleukin-1beta and TNF-alpha, increased NO synthesis. These results suggest that NO production in Eskol cells results from inducible NO synthase activity. This is the first direct demonstration of NO formation in human lymphoid cells. The cell line, Eskol, may serve as a model to study regulation of TNF-alpha and NO synthesis in human B-cell leukemia.


Assuntos
Leucemia de Células Pilosas/metabolismo , Óxido Nítrico/biossíntese , Células Tumorais Cultivadas/metabolismo , Fator de Necrose Tumoral alfa/biossíntese , Dexametasona/farmacologia , Humanos , Interferon gama/farmacologia , Interleucina-1/farmacologia , Nitratos/análise , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase/farmacologia , Fito-Hemaglutininas/farmacologia , Acetato de Tetradecanoilforbol/farmacologia , Fator de Necrose Tumoral alfa/efeitos dos fármacos , Fator de Necrose Tumoral alfa/farmacologia
14.
Eur J Clin Invest ; 28(3): 214-9, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9568467

RESUMO

BACKGROUND: Interleukin 1 (IL-1) and its physiological antagonist interleukin-1 receptor antagonist (IL-1 ra) play a crucial role in the pathogenesis of inflammatory bowel disease. Polymorphisms in the genes coding for these cytokines, the restriction enzyme TaqI polymorphism for IL-1 beta and the variable number of tandem repeats (VNTR) polymorphism for IL-1 ra, have been shown to influence cytokine synthesis in vitro. Recently, an association has been described for distinct allele combinations of these two polymorphisms in patients with ulcerative colitis and with Crohn's disease but not in healthy control subjects. METHODS: We studied 56 patients with ulcerative colitis, 64 patients with Crohn's disease and 196 healthy control subjects. All were unrelated Caucasians of European ancestry. After polymerase chain reaction (PCR) the amplification products were analysed on agarose gels. For the IL-1 beta polymorphism the PCR product was additionally digested using the restriction enzyme TaqI. RESULTS: The allele and genotype frequencies as well as the carriage rates of the IL-1 beta TaqI polymorphism in healthy control subjects were in agreement with previous findings in other populations. Allele and genotype frequencies of the IL-1 beta polymorphism were not different in inflammatory bowel disease patients compared with healthy control subjects. Comparing allele combinations of both polymorphisms no association could be identified either within healthy control subjects or in the groups of patients with ulcerative colitis or Crohn's disease. CONCLUSION: Thus, we could not confirm the results of a previous study reporting an association between the IL-1ra and IL-1 beta gene polymorphisms in patients with inflammatory bowel disease.


Assuntos
Doenças Inflamatórias Intestinais/genética , Doenças Inflamatórias Intestinais/imunologia , Interleucina-1/genética , Sialoglicoproteínas/genética , Adulto , Alelos , Sequência de Bases , Colite Ulcerativa/genética , Colite Ulcerativa/imunologia , Doença de Crohn/genética , Doença de Crohn/imunologia , Primers do DNA/genética , Feminino , Humanos , Proteína Antagonista do Receptor de Interleucina 1 , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Polimorfismo Genético
15.
J Infect Dis ; 177(3): 774-8, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9498462

RESUMO

Most knowledge about the synthesis of human tumor necrosis factor (TNF)-alpha and its regulation derives from in vitro studies. The hypothesis that the syndrome of malaise, myalgia, and low fever observed after a vaccination with live attenuated yellow fever virus could be associated with increased synthesis of TNF was investigated. Plasma samples of 15 healthy subjects taken before and until day 2 (until day 11 in 5 of these subjects) after yellow fever vaccination, showed a significant increase of plasma TNF concentration on day 2 after vaccination and a second peak on day 7. Interleukin-1 receptor antagonist (IL-1ra) concentration was significantly elevated in all subjects on day 2 after vaccination. In a control group receiving non-live vaccinations, TNF and IL-1ra concentrations were unchanged. Thus, yellow fever vaccination represents a routine medical intervention that results in a reproducible increase in the plasma concentration of TNF and secondary cytokines. This may serve as a unique model for the study of the regulation of TNF synthesis in vivo.


Assuntos
Fator de Necrose Tumoral alfa/biossíntese , Vacinação , Vacinas Virais/imunologia , Febre Amarela/prevenção & controle , Adulto , Humanos , Proteína Antagonista do Receptor de Interleucina 1 , Interleucina-6/sangue , Receptores do Fator de Necrose Tumoral/sangue , Sialoglicoproteínas/sangue , Vacinas Virais/uso terapêutico
16.
Gut ; 40(5): 623-7, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9203941

RESUMO

BACKGROUND: Recently, the association of a polymorphism in the gene coding for the anti-inflammatory cytokine interleukin-1 receptor antagonist with ulcerative colitis has been reported. This was interpreted as a possible genetic predisposition for severity of the inflammatory response. AIMS: To examine this polymorphism in a southern German population. SUBJECTS: The study included 234 healthy controls, 57 patients with ulcerative colitis, including 31 patients with pancolitis, 44 first degree healthy relatives of patients with ulcerative colitis, and 65 patients with Crohn's disease. METHODS: Genotypes were determined by a polymerase chain reaction amplification of the intron 2 fragment harbouring a variable number of tandem repeat nucleotide sequences. Amplification products were separated on a 2% agarose gel. RESULTS: The allele frequency for allele 2 was 27% in healthy controls, 28% in Crohn's disease, and 21% in patients with ulcerative colitis. The same allele frequency (21%) was found in a subgroup of patients with ulcerative colitis affecting the whole colon. Thus for allele 2 as well as for all other alleles, genotypes, or carriage rates no significant differences were found compared with controls. All allele frequencies in the control population were similar to those in earlier studies. CONCLUSIONS: No association of a polymorphism in the interleukin-1 receptor antagonist gene with ulcerative colitis could be identified in this southern German population. The findings of an earlier study reporting an increased frequency of allele 2, particularly in patients with pancolitis, could not be confirmed.


Assuntos
Colite Ulcerativa/genética , Interleucina-1 , Polimorfismo Genético , Sialoglicoproteínas/genética , Adulto , Idoso , Alelos , Suscetibilidade a Doenças , Feminino , Genótipo , Alemanha , Humanos , Proteína Antagonista do Receptor de Interleucina 1 , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase
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