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1.
Acta Ophthalmol ; 102(3): e314-e321, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-37725047

RESUMO

PURPOSE: The German Retina.net ROP registry and its Europe-wide successor, the EU-ROP registry, collect data from patients treated for ROP. This analysis compares input parameters of these two registries to establish a procedure for joint analyses of different registry data using exemplary datasets from the two registries. METHODS: Exemplary datasets from the two databases over a 1-year period each (German Retina.net ROP Registry, 2011, 22 infants; EU-ROP Registry, 2021, 44 infants) were compared. The parameters documented in the two databases were aligned and analysed regarding demographic parameters, treatment modalities, complications within first 24 h and retreatments. RESULTS: The current analysis showed that data can be aligned for joint analyses with some adjustments within the data structure. The registry with more detailed data collection (EU-ROP) needs to be reduced regarding granularity in order to align the different registries, as the registry with lower granularity determines the level of analyses that can be performed in a comparative approach. In the exemplary datasets, we observed that the overall most common ROP severity in both registries was zone II, 3+ (2011: 70.5%; 2021: 65%), with decreasing numbers of clock hours showing preretinal neovascularisations (2011: 10-12 clock hours in 29% of cases, 2021: 4-6 clock hours in 38%). The most prevalent treatment method was laser coagulation in 2011 (75%) and anti-VEGF therapy in 2021 (86.1%). Within the anti-VEGF group, all patients were treated with bevacizumab in 2011 and with ranibizumab in 2021. Retreatment rates were comparable in 2011 and 2021. CONCLUSION: Data from two different ROP registries can be aligned and jointly analysed. The analysis reveals a paradigm shift in treatment modalities, from predominantly laser to anti-VEGF, and within the anti-VEGF group from bevacizumab to ranibizumab in Germany. In addition, there was a trend towards earlier treatment in 2021.


Assuntos
Ranibizumab , Retinopatia da Prematuridade , Recém-Nascido , Lactente , Humanos , Bevacizumab/uso terapêutico , Inibidores da Angiogênese/uso terapêutico , Fator A de Crescimento do Endotélio Vascular , Retinopatia da Prematuridade/terapia , Injeções Intravítreas , Retina , Fotocoagulação a Laser/métodos , Sistema de Registros , Idade Gestacional
2.
Eur J Ophthalmol ; 34(1): 79-88, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37218157

RESUMO

INTRODUCTION: Gyrate atrophy (GA) is a rare retinal dystrophy due to biallelic pathogenic variants in the ornithine aminotransferase (OAT) gene, causing a 10-fold increase in plasma ornithine levels. It is characterized by circular patches of chorioretinal atrophy. However, a GA-like retinal phenotype (GALRP) without elevated ornithine levels has also been reported. The aim of this study is to compare the clinical characteristics of GA and GALRP and to identify possible discriminators. METHODS: A multicenter, retrospective chart review was performed at three German referral centres on patient records between 01/01/2009 and 31/12/2021. Records were screened for patients affected by GA or GALRP. Only patients with examination results for plasma ornithine levels and / or genetic testing of the OAT gene were included. Further clinical data was gathered where available. RESULTS: Ten patients (5 female) were included in the analysis. Three suffered from GA, while seven had a GALRP. Mean age (± SD) at onset of symptoms was 12.3 (± 3.5) years for GA compared with 46.7 (± 14.0) years for GALRP patients (p = 0.002). Mean degree of myopia was higher in GA (-8.0 dpt. ± 3.6) compared to GALRP patients (-3.8 dpt. ± 4.8, p = 0.04). Interestingly, all GA patients showed macular oedema, while only one GALRP patient did. Only one patient with GALRP had a positive family history, while two were immunosuppressed. DISCUSSION: Age of onset, refraction and presence of macular cystoid cavities appear to be discriminators between GA and GALRP. GALRP may encompass both genetic and non-genetic subtypes.


Assuntos
Atrofia Girata , Humanos , Feminino , Criança , Adolescente , Atrofia Girata/diagnóstico , Atrofia Girata/genética , Estudos Retrospectivos , Retina/patologia , Fenótipo , Ornitina , Atrofia/patologia
3.
Ophthalmologie ; 120(3): 294-300, 2023 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-36127450

RESUMO

Intravitreal injection of anti-vascular endothelial growth factor (VEGF) is the standard treatment for patients with neovascular age-related macular degeneration (nAMD). In addition to the approved substances ranibizumab (Lucentis®, Novartis) and aflibercept (Eylea®, Bayer), bevacizumab (Avastin®, Roche) is also available. Furthermore, brolucizumab (Beovu®, Novartis) has been approved and has been available in Germany since April 2020. The multicenter, noninterventional prospective BLUE SKY study investigates brolucizumab treatment with different schemes in 600 treatment-naive and pretreated nAMD patients in routine clinical practice over a 24-month period. Besides general patient data, visual acuity and treatment data will be documented. Fluorescein angiography, fundus photography, spectral domain optical coherence tomography and swept-source optical coherence tomography angiography will be performed and analyzed by reading centers. The focus of the analysis will be on the intraretinal and subretinal fluid distribution as well as morphological MNV changes and injection frequency. Also, safety and adverse drug effects of brolucizumab, with a specific focus on inflammatory complications, particularly retinal (occlusive) vasculitis will be evaluated.


Assuntos
Degeneração Macular Exsudativa , Estudos Prospectivos , Degeneração Macular Exsudativa/tratamento farmacológico , Angiofluoresceinografia , Acuidade Visual , Humanos , Inibidores da Angiogênese/uso terapêutico
4.
Ophthalmologe ; 115(6): 464-468, 2018 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-29654389

RESUMO

BACKGROUND: Intravitreal anti-VEGF therapy is a highly efficacious new treatment option for retinopathy of prematurity (ROP) with significant advantages over conventional therapy using retinal laser coagulation in selected cases. With growing experience in the clinical application over the last years, data about the potential long-term effects of this therapeutic approach are increasingly becoming available, such as those related to ROP-associated myopia, neurodevelopment and late recurrences of ROP. Knowledge of these effects is of direct relevance for the clinical management of affected children. METHODS: The article is based on a literature review of the covered topics. RESULTS: In addition to its therapeutic effect on retinal pathology, anti-VEGF therapy in ROP can also reduce ROP-associated myopia, most likely due to a normalization of anterior segment development. As the unresolved question of potential negative effects of bevacizumab on neurodevelopment remains of concern, the use of alternative treatment options, such as ranibizumab or laser coagulation should be considered. Treatment-requiring recurrences of ROP following anti-VEGF therapy have been reported as late as 69 weeks postmenstrual age, indicating that long-term frequent ophthalmological follow-up examinations are required. CONCLUSION: Long-term effects of anti-VEGF therapy in ROP differ significantly from alternative treatment options such as laser coagulation. These differences are of relevance for the choice of treatment modality and the follow-up regimen of treated children.


Assuntos
Retinopatia da Prematuridade , Inibidores da Angiogênese , Bevacizumab , Criança , Idade Gestacional , Humanos , Recém-Nascido , Injeções Intravítreas , Fotocoagulação a Laser , Fator A de Crescimento do Endotélio Vascular
5.
Ophthalmologe ; 115(6): 476-488, 2018 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-29637302

RESUMO

BACKGROUND: Retinopathy of prematurity (ROP) is one of the main reasons for childhood blindness. The number of infants requiring treatment, however, is low for individual centers. The Retina.net ROP registry has been founded to allow a joint analysis of treatment patterns and courses post treatment. OBJECTIVE: This paper reports treatment patterns over 5 years. MATERIAL AND METHODS: All infants born between January 2011 and December 2015 who were entered into the treatment registry by one of the 12 participating centers were analyzed. RESULTS: The data of 150 infants (292 eyes) were analyzed and ROP 3+ in zone II was the most prevalent treatment indication. Gestational age and birth weight remained stable over the years. The treatment patterns, however, changed with anti-VEGF treatment (bevacizumab or ranibizumab) accounting for only 10% of treated eyes in 2011 but for 56% and 30% in 2014 and 2015, respectively. Almost all eyes with AP-ROP or zone I disease received anti-VEGF treatment. Zone II disease was predominantly treated with laser photocoagulation. Recurrences were more common and appeared later in the anti-VEGF group compared to the laser group (23%/interval 60 days vs. 17%/interval 23 days). Perioperative complications were evenly distributed across treatment groups. CONCLUSION: The data in this analysis represent about 10-15% of treated infants in Germany. The results provide evidence for an increasing use of anti-VEGF agents for ROP. The data reflect a selection bias for anti-VEGF treatment in eyes with a more aggressive disease. This needs to be considered when interpreting data such as disease recurrence rates. The risk for late recurrences after anti-VEGF treatment is of particular clinical significance.


Assuntos
Retinopatia da Prematuridade , Inibidores da Angiogênese , Alemanha , Idade Gestacional , Humanos , Lactente , Recém-Nascido , Injeções Intravítreas , Fotocoagulação a Laser , Sistema de Registros , Retina , Fator A de Crescimento do Endotélio Vascular
7.
Ophthalmologe ; 111(2): 113-20, 2014 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-24346958

RESUMO

BACKGROUND: In addition to topical, periocular and systemic administration, intravitreal injection has been established in recent years as an additional standard procedure for ophthalmological drug delivery. This route of administration is now most frequently used for the therapy of retinal diseases with vascular endothelial growth factor (VEGF) inhibitors. MATERIAL AND METHODS: A selective literature review and an analysis of own research data were carried out. RESULTS: Intravitreal administration achieves high drug concentrations in the target tissue while minimizing systemic drug exposure. Depending on properties such as molecular weight and binding capacity to the neonatal Fc receptor, intravitreally applied VEGF inhibitors can exhibit relevant differences in intraocular and systemic pharmacokinetics. Moreover, the pharmacokinetics can be affected by properties of the individual eye, such as ocular volume, vitreous liquefaction, and prior vitrectomy. CONCLUSIONS: Pharmacokinetics of intravitreally administered drugs determine both the duration of ocular effect and the degree of systemic exposure and are thus of clinical relevance with regard to the reinjection strategy and systemic safety.


Assuntos
Absorção Ocular/fisiologia , Soluções Oftálmicas/administração & dosagem , Soluções Oftálmicas/farmacocinética , Retina/efeitos dos fármacos , Retina/metabolismo , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/farmacocinética , Disponibilidade Biológica , Produtos Biológicos/administração & dosagem , Produtos Biológicos/farmacocinética , Humanos , Injeções Intravítreas , Taxa de Depuração Metabólica , Modelos Biológicos
8.
Ophthalmologe ; 109(12): 1189-97, 2012 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-23212356

RESUMO

Retinopathy of prematurity is one of only few potentially blinding retinal diseases of infancy amenable to prevention of visual loss by appropriate and timely therapeutic measures. Retinal ablative therapies, such as laser coagulation eliminate the disease-causing secretion of vascular endothelial growth factor (VEGF) by the avascular peripheral retina. Blockage of VEGF activity by intravitreal administration of VEGF-inhibitory drugs has likewise proven effective in recent clinical studies. Advanced stages of the disease may require surgical intervention. Knowledge of indications and techniques of the different currently available treatment options is crucial to ensure an optimal visual outcome for the affected children.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Fotocoagulação a Laser/tendências , Procedimentos Cirúrgicos Oftalmológicos/tendências , Oftalmologia/tendências , Retinopatia da Prematuridade/diagnóstico , Retinopatia da Prematuridade/terapia , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Feminino , Humanos , Recém-Nascido , Injeções Intravítreas , Masculino
9.
Klin Monbl Augenheilkd ; 229(10): 1024-9, 2012 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-22961043

RESUMO

Retinopathy of prematurity (ROP), like other angioproliferative retinal disorders, has witnessed the advent of anti-VEGF therapy in clinical practice. The first report from the BEAT-ROP study published in 2011 represents the first comparison of anti-VEGF therapy versus conventional laser treatment in a randomised controlled trial. This review article investigates these novel aspects of ROP therapy from a pathophysiological angle and delineates the stages of ROP in which anti-VEGF treatment appears as a reasonable option. Furthermore, the novel chances of anti-VEGF therapy are being weighed against some still unanswered questions and novel study concepts are being presented.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Terapia a Laser/tendências , Procedimentos Cirúrgicos Oftalmológicos/tendências , Retinopatia da Prematuridade/cirurgia , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Terapia Combinada , Feminino , Humanos , Recém-Nascido , Masculino , Retinopatia da Prematuridade/fisiopatologia
10.
Ophthalmologe ; 107(12): 1160-3, 2010 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-21052679

RESUMO

We present clinical images of a case of Leber's idiopathic stellate neuroretinitis (LISN). A 34-year-old male presented with acute-onset unilateral blurred vision for 5 days. Clinical examination revealed sectorial papillary edema and extensive macular edema in the affected eye. Using optical coherence tomography we detected intraretinal fluid in the outer retinal layers and subretinal fluid under the fovea. Seven days later, the macular edema was completely resolved, and disseminated retinal exudates had appeared, resembling a macular star figure. No underlying systemic disease was identified. Follow-up examination after 3 months demonstrated almost complete spontaneous resolution of fundus changes and near-normalization of visual acuity.


Assuntos
Edema Macular/etiologia , Papiledema/etiologia , Retinite/diagnóstico , Transtornos da Visão/etiologia , Adulto , Diagnóstico Diferencial , Angiofluoresceinografia , Seguimentos , Humanos , Masculino , Remissão Espontânea , Retina/patologia , Retinite/patologia , Tomografia de Coerência Óptica , Acuidade Visual/fisiologia
11.
Br J Ophthalmol ; 93(1): 91-5, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18952645

RESUMO

BACKGROUND: Translocation of an autologous retinal pigment epithelium (RPE) sheet under the macula is currently under investigation as a treatment for exudative AMD. Excimer laser-assisted RPE sheet translocation (EST) employs intraocular excimer ablation of excess graft choroidal tissue as a measure to enhance RPE sheet functionality. This study assessed potential adverse effects of excimer irradiation on RPE cells in vitro. METHODS: Human RPE cells (ARPE-19) received 308 nm XeCl excimer laser treatment or 311-312 nm UV-B irradiation. Cell death was visualised with Trypan Blue and quantified by LDH release assay. Apoptosis was detected by DNA fragmentation assay. RESULTS: Laser treatment of 0.175-0.25 J/cm(2) resulted in delayed cell death within 48 h. Time course and dose response paralleled the effect of UV-B irradiation. Cytotoxicity was mediated by apoptosis. Human choroid/Bruch membrane tissue sheets covering the cells during laser irradiation reduced cytotoxicity by 87-95%. CONCLUSION: Cultured human RPE cells are susceptible to apoptotic cell death induced by 308 nm excimer laser irradiation. Absorption by choroid/Bruch membrane tissue can largely prevent the cytotoxic effect. In clinical application, the residual adverse effect of laser ablation on graft RPE cell viability needs to be outweighed by potential advantageous effects on graft survival and functionality to allow for a sensible application of excimer ablation in RPE translocation surgery.


Assuntos
Lasers de Excimer/efeitos adversos , Degeneração Macular/cirurgia , Epitélio Pigmentado da Retina/citologia , Lâmina Basilar da Corioide/citologia , Morte Celular/fisiologia , Sobrevivência Celular/efeitos da radiação , Células Cultivadas , Corioide/citologia , Sobrevivência de Enxerto/fisiologia , Humanos , Degeneração Macular/metabolismo , Epitélio Pigmentado da Retina/efeitos da radiação , Epitélio Pigmentado da Retina/cirurgia
12.
Ophthalmologe ; 102(12): 1152-61, 2005 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-16283184

RESUMO

BACKGROUND: Evidence-based medicine requires careful appraisal of published data derived from experimental and clinical studies. Based on classification of biomedical research reports, evidence levels can be determined and recommendations for therapeutic decisions can be made. METHODS: A classification system for clinical studies was developed. It was evaluated in classifying the reports published in Der Ophthalmologe during 2003-2004 (study design: descriptive cross-sectional study, case series). RESULTS: In the 2-year interval, 70 longitudinal and 95 cross-sectional studies were published. The vast majority of the longitudinal studies were interventional cohort studies. Not considering case reports, 73% of the original articles were longitudinal prospective studies, 1% were retrospective (case-control) studies, and 26% were cross-sectional studies. CONCLUSIONS: The study design of all published articles could be classified using the classification system. This classification system proves to be applicable in the context of clinical studies in ophthalmology and may be helpful in the process of critical appraisal of the literature and synthesis of clinical evidence and an evidence-based recommendation.


Assuntos
Pesquisa Biomédica/classificação , Pesquisa Biomédica/estatística & dados numéricos , Ensaios Clínicos como Assunto/normas , Medicina Baseada em Evidências/normas , Oftalmologia/normas , Publicações Periódicas como Assunto/classificação , Publicações Periódicas como Assunto/estatística & dados numéricos , Bibliometria , Ensaios Clínicos como Assunto/estatística & dados numéricos , Medicina Baseada em Evidências/estatística & dados numéricos , Alemanha , Oftalmologia/estatística & dados numéricos , Publicações Periódicas como Assunto/normas , Padrões de Referência
14.
Ophthalmologe ; 100(4): 300-5, 2003 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-12682762

RESUMO

Age-related macular degeneration (AMD) is the leading cause of blindness in the developed world but the pathogenesis remains poorly understood. Malfunction of the retinal pigment epithelium (RPE) plays a central role in the disease and leads to either choriodal atrophy or proliferation. This article reviews the current concepts of the development of choriodal atrophy and neovascularisation. Furthermore, available animal models and potential therapeutical targets are discussed.


Assuntos
Neovascularização de Coroide/etiologia , Degeneração Macular/complicações , Fatores Etários , Inibidores da Angiogênese/uso terapêutico , Animais , Anti-Inflamatórios/uso terapêutico , Células Cultivadas , Neovascularização de Coroide/complicações , Neovascularização de Coroide/genética , Neovascularização de Coroide/fisiopatologia , Neovascularização de Coroide/terapia , Corioidite/complicações , Ensaios Clínicos Fase III como Assunto , Ensaios Clínicos Controlados como Assunto , Modelos Animais de Doenças , Fatores de Crescimento Endotelial/antagonistas & inibidores , Fatores de Crescimento Endotelial/uso terapêutico , Traumatismos Oculares/complicações , Haplorrinos , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/uso terapêutico , Interferon gama/uso terapêutico , Terapia a Laser , Linfocinas/antagonistas & inibidores , Linfocinas/uso terapêutico , Macula Lutea/transplante , Degeneração Macular/terapia , Camundongos , Camundongos Transgênicos , Miopia/complicações , Fotoquimioterapia , Epitélio Pigmentado Ocular/citologia , Ratos , Neovascularização Retiniana/etiologia , Neovascularização Retiniana/fisiopatologia , Fatores de Risco , Triancinolona/uso terapêutico , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
15.
Gastroenterology ; 121(4): 931-9, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11606506

RESUMO

BACKGROUND & AIMS: Priming immune responses against alpha-fetoprotein (AFP) highly expressed in the majority of hepatocellular carcinomas results in significant antitumoral T-cell responses. Liver regeneration in humans and mice, however, is also associated with increased AFP expression. Therefore, we evaluated the risk of AFP-directed immunotherapeutic approaches to induce autoimmunity against the regenerating liver. METHODS: Mice were immunized with DNA encoding mouse AFP. For induction of liver regeneration, partial hepatectomy was performed and mice were monitored by serial histopathologic examinations and measurements of serum ALT activities (U/L), and by determination of the kinetics of AFP-specific T-cell responses. RESULTS: Livers of AFP immune mice without partial hepatectomy were characterized by minor lymphocytic infiltrations without transaminase elevations. By contrast, a significant hepatocyte damage was observed in regenerating liver that correlated well with the number of AFP-specific CD8(+) T cells, the activity of liver regeneration, and the level of AFP synthesis. Autoimmune liver damage was mediated by CD4(+) T cell-dependent CD8(+) cytotoxic T lymphocytes. CONCLUSIONS: These results show that priming of T-cell responses against shared tumor-specific self antigens may be accompanied by induction of autoimmunity dependent on the level of expression of the self antigen and have important implications for the development of antitumoral vaccines targeted against antigens that are not strictly tumor-specific.


Assuntos
Doenças Autoimunes/etiologia , Imunoterapia/métodos , Hepatopatias/etiologia , Regeneração Hepática/imunologia , Linfócitos T/imunologia , alfa-Fetoproteínas/imunologia , Animais , Linfócitos T CD8-Positivos/imunologia , Citotoxicidade Imunológica , Hepatectomia , Hepatócitos/imunologia , Hepatócitos/patologia , Humanos , Hepatopatias/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Modelos Animais , alfa-Fetoproteínas/genética
16.
Hepatology ; 34(3): 511-8, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11526536

RESUMO

For gene therapy of hepatocellular carcinoma (HCC), the Escherichia coli purine nucleoside phosphorylase (PNP)/fludarabine suicide gene system may be more useful than the herpes simplex virus thymidine kinase/ganciclovir (HSV-tk/GCV) system as a result of a stronger bystander effect. To analyze the molecular mechanisms involved in PNP/fludarabine-mediated cell death in human HCC cells in comparison with HSV-tk/GCV, we transduced human HCC cells of the cell lines, HepG2 and Hep3B, with PNP or HSV-tk using adenoviral vectors, followed by prodrug incubation. Both systems predominantly induced apoptosis in HepG2 and Hep3B cells. PNP/fludarabine induced strong p53 accumulation and a more rapid onset of apoptosis in p53-positive HepG2 cells as compared with p53-negative Hep3B cells, but efficiency of tumor cell killing was similar in both cell lines. In contrast, HSV-tk/GCV-induced apoptosis was reduced in p53-negative Hep3B cells as compared with p53-positive HepG2 cells. HSV-tk/GCV, but not PNP/fludarabine, caused up-regulation of Fas in p53-positive HepG2 cells and of Fas ligand (FasL) in both HCC cell lines. These results demonstrate cell line-specific differences in response to treatment with PNP/fludarabine and HSV-tk/GCV, respectively, and indicate that PNP/fludarabine may be superior to HSV-tk/GCV for the treatment of human HCC because of its independence from p53 and the Fas/FasL system.


Assuntos
Carcinoma Hepatocelular/fisiopatologia , Carcinoma Hepatocelular/terapia , Terapia Genética , Neoplasias Hepáticas/fisiopatologia , Neoplasias Hepáticas/terapia , Purina-Núcleosídeo Fosforilase/genética , Timidina Quinase/genética , Apoptose , Carcinoma Hepatocelular/patologia , Morte Celular/genética , Proteína Ligante Fas , Proteínas de Choque Térmico HSP70/metabolismo , Humanos , Neoplasias Hepáticas/patologia , Glicoproteínas de Membrana/metabolismo , Células Tumorais Cultivadas , Proteína Supressora de Tumor p53/metabolismo , Receptor fas/metabolismo
17.
Cancer Res ; 61(6): 2609-17, 2001 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-11289138

RESUMO

Hepatocellular carcinoma (HCC) is a highly malignant tumor with a poor prognosis and few therapeutic options. The aim of the study was to evaluate the potential of IFN regulatory factor-1 (IRF-1) for cytokine gene therapy of HCC using an IRF-1/human estrogen receptor fusion protein (IRF-1hER), which is reversibly activatable by beta-estradiol (E2). IRF-1hER stably expressing murine Hepa1-6 HCC cells (HepaIRF-1hER) were characterized by lowMHC 1, highCD54, and lack of MHC II, CD80, and CD86 expression. Activation of HepaIRF-1hER cells induced a highMHC I, lowMHC II, and highCD54 phenotype. Furthermore, they were characterized by IFN-beta secretion, decreased anchorage-independent growth in a soft agar assay, and diminished cell growth. Tumor growth in E2-treated syngeneic C57L/J mice, but not in E2-untreated mice, was suppressed. These E2-treated mice were protected against rechallenge with HepaIRF-1hER and wild-type Hepa1-6 tumors even in the absence of E2, suggesting induction of tumor specific immunity. In fact, significant CTL activity against Hepa1-6 tumors and the endogenously expressed HCC-specific self antigen alpha-fetoprotein was observed. Antitumoral effects, however, were only partially dependent on both CD4+ and CD8+ T cells. IRF-1 treatment of mice bearing HepaIRF-1hER tumors resulted in growth arrest of tumors, and a significant survival benefit was observed in comparison to E2-untreated mice. In conclusion, our data demonstrate that IRF-1 suppresses HCC growth through both a direct antitumor growth effect and enhanced immune cell recognition of the tumor and is a promising candidate for gene therapy of HCC.


Assuntos
Proteínas de Ligação a DNA/fisiologia , Terapia Genética , Neoplasias Hepáticas Experimentais/patologia , Fosfoproteínas/fisiologia , Proteínas Recombinantes de Fusão/genética , Animais , Adesão Celular , Divisão Celular/fisiologia , Proteínas de Ligação a DNA/genética , Estradiol/farmacologia , Humanos , Tolerância Imunológica/imunologia , Memória Imunológica/imunologia , Fator Regulador 1 de Interferon , Interferon beta/biossíntese , Interferon beta/metabolismo , Neoplasias Hepáticas Experimentais/genética , Neoplasias Hepáticas Experimentais/imunologia , Neoplasias Hepáticas Experimentais/terapia , Masculino , Camundongos , Camundongos Endogâmicos , Fosfoproteínas/genética , Plasmídeos/genética , Receptores de Estrogênio/genética , Linfócitos T/imunologia , Linfócitos T Citotóxicos/imunologia , Células Tumorais Cultivadas , alfa-Fetoproteínas/imunologia
18.
Gastroenterology ; 119(4): 1104-12, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11040197

RESUMO

BACKGROUND & AIMS: alpha-Fetoprotein (AFP) is a tumor-associated protein that is frequently expressed at high levels in hepatocellular carcinoma (HCC). The aim of the study was to characterize self-reactive cytotoxic T lymphocytes (CTLs) directed against murine AFP (mAFP) after DNA-based immunization in mice. METHODS: To study CTL responses, mAFP-expressing recombinant vaccinia viruses were generated. An HCC tumor model was established in C57L/J mice by injection of syngeneic endogenously mAFP-expressing Hepa1-6 cells. RESULTS: Gene gun and intramuscular coimmunizations of DNA expression vectors encoding mAFP with plasmids encoding murine interleukin (IL)-12, granulocyte-macrophage colony-stimulating factor, or IL-18 induced weak CTL activity against mAFP in different mouse strains. Some mice developed anti-mAFP antibody responses, suggesting breaking of immunologic ignorance. No hepatocyte damage was detectable despite low-level endogenous hepatic mAFP expression. Therapeutic immunizations of mice bearing mAFP-expressing murine HCCs induced partial regression of tumors. A significant survival benefit was observed in mice immunized with mAFP expression vector DNA but not in untreated mice or in mice immunized with mock/cytokine plasmid DNA. CONCLUSIONS: The data show that AFP may be used as a potential self tumor antigen to induce CTL and CD4(+) T cell-mediated regression of AFP-expressing HCC by DNA-based immunization.


Assuntos
Terapia Genética , Imunoterapia , Neoplasias Hepáticas Experimentais/terapia , Linfócitos T Citotóxicos/imunologia , alfa-Fetoproteínas/genética , Alanina Transaminase/sangue , Animais , Anticorpos Monoclonais/imunologia , Aspartato Aminotransferases/sangue , Biolística , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Citotoxicidade Imunológica , Feminino , Fator Estimulador de Colônias de Granulócitos e Macrófagos/genética , Fator Estimulador de Colônias de Granulócitos e Macrófagos/imunologia , Interleucina-12/genética , Interleucina-12/imunologia , Interleucina-18/genética , Interleucina-18/imunologia , Neoplasias Hepáticas Experimentais/imunologia , Neoplasias Hepáticas Experimentais/patologia , Depleção Linfocítica , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Plasmídeos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , alfa-Fetoproteínas/análise
19.
Hepatology ; 31(3): 606-14, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10706550

RESUMO

Expression of viral or bacterial enzymes in tumor cells to convert nontoxic prodrugs into highly toxic metabolites is an attractive gene-therapeutic approach for the treatment of hepatocellular carcinoma (HCC). The Escherichia coli purine nucleoside phosphorylase (PNP) converts purine analogs into freely diffusible metabolites, which are highly toxic to dividing and nondividing cells. We investigated the antitumor effects of PNP in the human HCC cell lines, HepG2, Hep3B, and HuH-7, and performed a comparison with herpes simplex thymidine kinase (TK). The genes for PNP, TK, and enhanced green fluorescent protein (EGFP) were delivered to HCC cells by identical adenoviral vectors. Fludarabine and ganciclovir (GCV) served as prodrugs for PNP and TK, respectively. Expression of PNP highly sensitized HCC cells to fludarabine treatment. Fludarabine concentrations between 0.5 and 1 microg/mL killed 100% of the cells expressing PNP with no detectable toxicity in control cells expressing EGFP. Expression of PNP in as few as 10% of HCC cells induced efficient killing of most bystander cells. Expression of TK followed by GCV treatment produced a potent growth inhibition but failed to kill all TK-expressing HCC cells. More importantly, the TK system exhibited a lower degree of bystander effect. Adenoviral delivery of PNP followed by fludarabine administration prevented subcutaneous and intrahepatic tumor formation in nude mice and was also effective for the treatment of established tumors. These results demonstrate the potential of the PNP/fludarabine system for the treatment of HCC.


Assuntos
Neoplasias Hepáticas Experimentais/terapia , Orotato Fosforribosiltransferase/genética , Adenoviridae/genética , Animais , Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Sobrevivência Celular , Terapia Combinada , Escherichia coli/enzimologia , Escherichia coli/genética , Ganciclovir/administração & dosagem , Técnicas de Transferência de Genes , Terapia Genética , Vetores Genéticos , Proteínas de Fluorescência Verde , Humanos , Neoplasias Hepáticas Experimentais/prevenção & controle , Proteínas Luminescentes/genética , Camundongos , Camundongos Nus , RNA Mensageiro/análise , Timidina Quinase/genética , Células Tumorais Cultivadas , Vidarabina/administração & dosagem , Vidarabina/análogos & derivados , Vidarabina/uso terapêutico
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