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2.
Retin Cases Brief Rep ; 16(3): 344-346, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32058354

RESUMO

BACKGROUND/PURPOSE: To report a case of unilateral choroidal detachment and serous retinal detachment in a patient with a history of untreated sarcoidosis. METHODS: Case report. The patient is a 67-year-old African American man with a history of nontreated sarcoidosis and prostate cancer. His prostate cancer was treated several years earlier with external beam radiation therapy. The patient presented with blurred visual acuity of 20/30 and floaters in the right eye. He was discovered to have several hypopigmented choroidal lesions, 360-degree choroidal detachment, and shallow serous retinal detachment in the right eye. RESULTS: The patient was treated with subtenons kenalog and oral prednisone with subsequent improvement of vision and resolution of choroidal and retinal detachment. CONCLUSION: Ocular sarcoidosis can involve any part of the eye and its adnexal tissues and may cause uveitis, episcleritis, scleritis, eyelid abnormalities, conjunctival granuloma, optic neuropathy, lacrimal gland enlargement, and orbital inflammation. Most patients with ophthalmic sarcoidosis have evidence of systemic involvement at the time of the initial examination and have bilateral ocular presentation. We present here the unique case of a 67-year-old man with unilateral 360-degree choroidal detachment and serous retinal detachment as an ocular presentation of sarcoidosis.


Assuntos
Efusões Coroides , Neoplasias da Próstata , Descolamento Retiniano , Sarcoidose , Esclerite , Uveíte , Idoso , Humanos , Masculino , Neoplasias da Próstata/complicações , Descolamento Retiniano/diagnóstico , Descolamento Retiniano/etiologia , Sarcoidose/complicações , Sarcoidose/diagnóstico
3.
Retina ; 40(5): 943-950, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-30883531

RESUMO

PURPOSE: To determine the preoperative characteristics, intraoperative and postoperative complications, and outcomes of eyes with posteriorly inserted vitreous base. METHODS: In this retrospective, observational, consecutive case series at 2 academic centers, 37 patients were studied who had posteriorly inserted vitreous base noted during vitrectomy. Posteriorly inserted vitreous base was defined as the insertion of the posterior hyaloid membrane being located posterior to the vortex veins. Fifteen eyes were analyzed in a histopathologic study of donor eyes to determine the average distance of the ora serrata from the vortex veins as this distance is uncertain. RESULTS: Posteriorly inserted vitreous base was identified during vitrectomy in 31 eyes with rhegmatogenous retinal detachment (84%), 4 with macular hole (11%), 1 with vitreous hemorrhage, and 1 with epiretinal membrane. Adjunctive buckle was used in 24%; 54% had 360° laser. Average number of tears seen preoperatively in those with rhegmatogenous retinal detachment was 3.1. Thirty percent had new breaks identified intraoperatively. Forty-one percent had lattice degeneration; new breaks were found in 40% of eyes with lattice. Thirteen percent of rhegmatogenous retinal detachments developed proliferative vitreoretinopathy. Average distance from the ora serrata to the vortex veins was 7.6 mm. CONCLUSION: Any eye undergoing vitrectomy may have posteriorly inserted vitreous base, but those with a high number of retinal breaks and lattice near the equator may be at highest risk. Redetachment and proliferative vitreoretinopathy still occur despite knowledge of the disorder and adjuvant treatments.


Assuntos
Retina/diagnóstico por imagem , Doenças Retinianas/cirurgia , Acuidade Visual , Vitrectomia/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Período Intraoperatório , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Doenças Retinianas/diagnóstico , Estudos Retrospectivos
4.
Retina ; 40(9): 1719-1723, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31800459

RESUMO

PURPOSE: To evaluate alterations in treatment burden and course of exudative age-related macular degeneration in patients who contracted endophthalmitis from intravitreal anti-vascular endothelial growth factor (anti-VEGF) injections. METHODS: Retrospective study at the University of Pittsburgh Medical Center examining frequency of anti-VEGF injections, activity of choroidal neovascularization, and visual acuity before and after endophthalmitis treatment. RESULTS: Twenty-one patients meeting inclusion criteria were identified, of whom 7 (33%) patients did not restart anti-VEGF treatment 12 months after endophthalmitis because of quiescence of exudative age-related macular degeneration without significant visual acuity loss (P > 0.05). Patients who resumed anti-VEGF treatment exhibited 32% and 38% decreases in injection frequency by 12 and 24 months after endophthalmitis, respectively (P < 0.05). On first optical coherence tomography follow-up, 10 patients exhibited quiescence of choroidal neovascularization activity, although there were no measurable changes in macular thickness (P > 0.05). No differences in post-endophthalmitis exudative age-related macular degeneration progression or treatment burden were observed when factoring adjuvant intravitreal steroid therapy, culture results, nor choroidal neovascularization subtypes. CONCLUSION: Endophthalmitis resolution is associated with a decrease in choroidal neovascularization activity and a reduction of anti-VEGF treatment burden in patients with exudative age-related macular degeneration.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Neovascularização de Coroide/fisiopatologia , Endoftalmite/tratamento farmacológico , Infecções Oculares Bacterianas/tratamento farmacológico , Injeções Intravítreas/efeitos adversos , Degeneração Macular Exsudativa/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/uso terapêutico , Bevacizumab/uso terapêutico , Neovascularização de Coroide/tratamento farmacológico , Endoftalmite/etiologia , Exsudatos e Transudatos , Infecções Oculares Bacterianas/etiologia , Feminino , Angiofluoresceinografia , Humanos , Masculino , Pessoa de Meia-Idade , Ranibizumab/uso terapêutico , Estudos Retrospectivos , Tomografia de Coerência Óptica , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Acuidade Visual/fisiologia , Degeneração Macular Exsudativa/tratamento farmacológico
5.
J AAPOS ; 23(2): 86.e1-86.e7, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30885809

RESUMO

PURPOSE: To evaluate the effect of a computer-based training program-Massachusetts Eye & Ear ROP Trainer-on residents' knowledge of retinopathy of prematurity (ROP) management. METHODS: In this prospective, randomized study, ophthalmology residents from nine different training programs consented to participate. Those who completed the study were randomly assigned to either the Trainer or the control group. The ROP Trainer was created using clinical cases encompassing the stages of ROP in digital pictures and videos. It includes sections on screening decisions, examination techniques, and diagnosis, and a reference section with the expert video clips and a searchable image library. Subjects in the control group were asked to study standard print material on ROP. A pre- and post-test, consisting of theoretical and practical (diagnosis) questions, and a post-intervention satisfaction test were administered. Accuracy of ROP diagnosis was assessed. RESULTS: A total of 180 residents agreed to participate, of whom 60 completed the study. Residents in the Trainer group had statistically significant improvements (P = 0.003) in ROP knowledge and diagnostic ability (P = 0.005). Residents randomized to the Trainer group were more satisfied with the training materials than were those in the control group. There was no significant difference in improving knowledge by year of training, sex, or country. Considering all training levels, a statistically significant increase was observed in sensitivity for the diagnosis of preplus or worse, zone I or II, ROP stage, category, and aggressive posterior ROP in the Trainer group. CONCLUSIONS: In this study, the Trainer was shown to significantly improve ROP knowledge and diagnostic skills of residents, regardless of sex, year, of training, or country.


Assuntos
Competência Clínica/normas , Instrução por Computador/métodos , Internato e Residência/métodos , Oftalmologia/educação , Retinopatia da Prematuridade/diagnóstico , Retroalimentação , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Massachusetts , Oftalmologia/normas , Estudos Prospectivos , Retinopatia da Prematuridade/terapia
6.
Sci Rep ; 7(1): 7602, 2017 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-28790340

RESUMO

Verteporfin (VP), a light-activated drug used in photodynamic therapy for the treatment of choroidal neovascular membranes, has also been shown to be an effective inhibitor of malignant cells. Recently, studies have demonstrated that, even without photo-activation, VP may still inhibit certain tumor cell lines, including ovarian cancer, hepatocarcinoma and retinoblastoma, through the inhibition of the YAP-TEAD complex. In this study, we examined the effects of VP without light activation on human glioma cell lines (LN229 and SNB19). Through western blot analysis, we identified that human glioma cells that were exposed to VP without light activation demonstrated a downregulation of YAP-TEAD-associated downstream signaling molecules, including c-myc, axl, CTGF, cyr61 and survivin and upregulation of the tumor growth inhibitor molecule p38 MAPK. In addition, we observed that expression of VEGFA and the pluripotent marker Oct-4 were also decreased. Verteporfin did not alter the Akt survival pathway or the mTor pathway but there was a modest increase in LC3-IIB, a marker of autophagosome biogenesis. This study suggests that verteporfin should be further explored as an adjuvant therapy for the treatment of glioblastoma.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas de Ligação a DNA/genética , Regulação Neoplásica da Expressão Gênica , Neuroglia/efeitos dos fármacos , Proteínas Nucleares/genética , Fosfoproteínas/genética , Fármacos Fotossensibilizantes/farmacologia , Fatores de Transcrição/genética , Verteporfina/farmacologia , Proteínas Adaptadoras de Transdução de Sinal/antagonistas & inibidores , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Fator de Crescimento do Tecido Conjuntivo/antagonistas & inibidores , Fator de Crescimento do Tecido Conjuntivo/genética , Fator de Crescimento do Tecido Conjuntivo/metabolismo , Proteína Rica em Cisteína 61/antagonistas & inibidores , Proteína Rica em Cisteína 61/genética , Proteína Rica em Cisteína 61/metabolismo , Proteínas de Ligação a DNA/antagonistas & inibidores , Proteínas de Ligação a DNA/metabolismo , Humanos , Proteínas Associadas aos Microtúbulos/agonistas , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Neuroglia/metabolismo , Neuroglia/patologia , Proteínas Nucleares/antagonistas & inibidores , Proteínas Nucleares/metabolismo , Fator 3 de Transcrição de Octâmero/antagonistas & inibidores , Fator 3 de Transcrição de Octâmero/genética , Fator 3 de Transcrição de Octâmero/metabolismo , Fosfoproteínas/antagonistas & inibidores , Fosfoproteínas/metabolismo , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-myc/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Receptores Proteína Tirosina Quinases/antagonistas & inibidores , Receptores Proteína Tirosina Quinases/genética , Receptores Proteína Tirosina Quinases/metabolismo , Transdução de Sinais , Survivina/genética , Survivina/metabolismo , Fatores de Transcrição de Domínio TEA , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/metabolismo , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Proteínas de Sinalização YAP , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Receptor Tirosina Quinase Axl
7.
Sci Rep ; 7: 46581, 2017 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-28429726

RESUMO

Verteporfin (VP) was first used in Photodynamic therapy, where a non-thermal laser light (689 nm) in the presence of oxygen activates the drug to produce highly reactive oxygen radicals, resulting in local cell and tissue damage. However, it has also been shown that Verteporfin can have non-photoactivated effects such as interference with the YAP-TEAD complex of the HIPPO pathway, resulting in growth inhibition of several neoplasias. More recently, it was proposed that, another non-light mediated effect of VP is the formation of cross-linked oligomers and high molecular weight protein complexes (HMWC) that are hypothesized to interfere with autophagy and cell growth. Here, in a series of experiments, using human uveal melanoma cells (MEL 270), human embryonic kidney cells (HEK) and breast cancer cells (MCF7) we showed that Verteporfin-induced HMWC require the presence of light. Furthermore, we showed that the mechanism of this cross-linking, which involves both singlet oxygen and radical generation, can occur very efficiently even after lysis of the cells, if the lysate is not protected from ambient light. This work offers a better understanding regarding VP's mechanisms of action and suggests caution when one studies the non-light mediated actions of this drug.


Assuntos
Luz , Complexos Multiproteicos/metabolismo , Neoplasias , Fotoquimioterapia , Fármacos Fotossensibilizantes , Verteporfina , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas de Ligação a DNA/metabolismo , Células HEK293 , Via de Sinalização Hippo , Humanos , Células MCF-7 , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/patologia , Fosfoproteínas/metabolismo , Fármacos Fotossensibilizantes/farmacocinética , Fármacos Fotossensibilizantes/farmacologia , Proteínas Serina-Treonina Quinases/metabolismo , Fatores de Transcrição , Verteporfina/farmacocinética , Verteporfina/farmacologia , Proteínas de Sinalização YAP
8.
Ophthalmology ; 124(5): 674-678, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28153439

RESUMO

PURPOSE: The Retinal Detachment after Open Globe Injury (RD-OGI) Score is a clinical prediction model that was developed at the Massachusetts Eye and Ear Infirmary to predict the risk of retinal detachment (RD) after open globe injury (OGI). This study sought to validate the RD-OGI Score in an independent cohort of patients. DESIGN: Retrospective cohort study. PARTICIPANTS: The predictive value of the RD-OGI Score was evaluated by comparing the original RD-OGI Scores of 893 eyes with OGI that presented between 1999 and 2011 (the derivation cohort) with 184 eyes with OGI that presented from January 1, 2012, to January 31, 2014 (the validation cohort). METHODS: Three risk classes (low, moderate, and high) were created and logistic regression was undertaken to evaluate the optimal predictive value of the RD-OGI Score. A Kaplan-Meier survival analysis evaluated survival experience between the risk classes. MAIN OUTCOME MEASURES: Time to RD. RESULTS: At 1 year after OGI, 255 eyes (29%) in the derivation cohort and 66 eyes (36%) in the validation cohort were diagnosed with an RD. At 1 year, the low risk class (RD-OGI Scores 0-2) had a 3% detachment rate in the derivation cohort and a 0% detachment rate in the validation cohort, the moderate risk class (RD-OGI Scores 2.5-4.5) had a 29% detachment rate in the derivation cohort and a 35% detachment rate in the validation cohort, and the high risk class (RD-OGI scores 5-7.5) had a 73% detachment rate in the derivation cohort and an 86% detachment rate in the validation cohort. Regression modeling revealed the RD-OGI to be highly discriminative, especially 30 days after injury, with an area under the receiver operating characteristic curve of 0.939 in the validation cohort. Survival experience was significantly different depending upon the risk class (P < 0.0001, log-rank chi-square). CONCLUSIONS: The RD-OGI Score can reliably predict the future risk of developing an RD based on clinical variables that are present at the time of the initial evaluation after OGI.


Assuntos
Ferimentos Oculares Penetrantes/complicações , Descolamento Retiniano/epidemiologia , Medição de Risco/métodos , Adulto , Ferimentos Oculares Penetrantes/diagnóstico , Feminino , Seguimentos , Humanos , Incidência , Masculino , Massachusetts/epidemiologia , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Descolamento Retiniano/diagnóstico , Descolamento Retiniano/etiologia , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida/tendências , Fatores de Tempo , Índices de Gravidade do Trauma , Acuidade Visual
10.
J Inorg Biochem ; 143: 34-47, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25486205

RESUMO

Hydrazone hesperetin Schiff base (HHSB) - N-[(±)-[5,7-dihydroxy-2-(3-hydroxy-4-methoxy-phenyl)chroman-4-ylidene]amino]benzamide has been synthesized and its crystal structure was determined. This compound was used for the formation of Cu(II) complexes in solid state and in solution which were characterized using different spectroscopic methods. The analyses of potentiometric titration curves revealed that monomeric and dimeric complexes of Cu(II) are formed above pH7. The ESI-MS (electrospray ionization-mass spectrometry) spectra confirmed their formation. The EPR and UV-visible spectra evidenced the involvement of oxygen and nitrogen atoms in Cu(II) coordination. Hydrazone hesperetin Schiff base can show keto-enol tautomerism and coordinate Cu(II) in the keto (O(-), N, Oket) and in the enolate form (O(-), N, O(-)enol). The semi-empirical molecular orbital method PM6 and DFT (density functional theory) calculations have revealed that the more stable form of the dimeric complex is that one in which the ligand is present in the enol form. The CuHHSB complex has shown high efficiency in the cleavage of plasmid DNA in aqueous solution, indicating its potential as chemical nuclease. Studies on DNA interactions, antimicrobial and cytotoxic activities have been undertaken to gain more information on the biological significance of HHSB and copper(II)-HHSB chelate species.


Assuntos
Quelantes/química , Cobre/química , DNA/química , Flavanonas/química , Plasmídeos/química , Hesperidina , Bases de Schiff/química
11.
J Food Sci ; 79(9): C1649-55, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25182178

RESUMO

The overall objective of this study was to develop a decontamination method against microorganisms in cardamom (Elettaria cardamomum (L.) Maton) seeds using ozone as a decontaminating agent. Ozone treatment was conducted 3 times, at 24-h intervals, and the parameters of the process were determined assuring the least possible losses of biologically active substances (essential oils and polyphenols): ozone concentration 160 to 165.0 g/m(3) ; flow rate 0.1 L/min; pressure 0.5 atm; time 30 min. After each step of decontamination, the microbiological profile of the cardamom seeds was studied, and the contaminating microflora was identified. Next to the microbiological profile, the total polyphenol content (TPC), composition of essential oils, free radical-scavenging capacity, total antioxidant capacity, ferric-reducing antioxidant power (FRAP), and LC-MS polyphenol analysis were determined. This study shows that extract from cardamom seeds after ozone treatment is characterized by a better radical scavenging activity (IC(50) = 24.18 ± 0.04 mg/mL) than the control sample (IC(50) = 31.94 ± 0.05 mg/mL). The extract from cardamom seeds after ozone treatment showed an improved FRAP activity as well (613.64 ± 49.79 mmol TE/g compared to 480.29 ± 30.91 mmol TE/g of control sample). The TPC and the total antioxidant capacity were negatively affected, respectively, 41.2% and 16.2%, compared to the control sample.


Assuntos
Elettaria/química , Ozônio/química , Polifenóis/química , Sementes/química , Elettaria/microbiologia , Microbiologia de Alimentos , Sequestradores de Radicais Livres/química , Óleos Voláteis/química , Extratos Vegetais/química , Óleos de Plantas/química , Sementes/microbiologia
12.
Int J Oncol ; 45(6): 2311-24, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25215935

RESUMO

Recent studies suggest that the anti-diabetic drug metformin may reduce the risk of cancer and have anti-proliferative effects for some but not all cancers. In this study, we examined the effects of metformin on human retinoblastoma cell proliferation in vitro and in vivo. Two different human retinoblastoma cell lines (Y79, WERI) were treated with metformin in vitro and xenografts of Y79 cells were established in nu/nu immune-deficient mice and used to assess the effects of pharmacological levels of metformin in vivo. Metformin inhibited proliferation of the retinoblastoma cells in vitro. Similar to other studies, high concentrations of metformin (mM) blocked the cell cycle in G0­G1, indicated by a strong decrease of G1 cyclins, especially cyclin D, cyclin-dependent kinases (4 and 6), and flow cytometry assessment of the cell cycle. This was associated with activation of AMPK, inhibition of the mTOR pathways and autophagy marker LC3B. However, metformin failed to suppress growth of xenografted tumors of Y79 human retinoblastoma cells in nu/nu mice, even when treated with a maximally tolerated dose level achieved in human patients. In conclusion, suprapharmacological levels (mM) of metformin, well above those tolerated in vivo, inhibited the proliferation of retinoblastoma cells in vitro. However, physiological levels of metformin, such as seen in the clinical setting, did not affect the growth of retinoblastoma cells in vitro or in vivo. This suggests that the potential beneficial effects of metformin seen in epidemiological studies may be limited to specific tumor types or be related to indirect effects/mechanisms not observed under acute laboratory conditions.


Assuntos
Proliferação de Células/efeitos dos fármacos , Metformina/administração & dosagem , Retinoblastoma/tratamento farmacológico , Proteínas Quinases Ativadas por AMP/biossíntese , Animais , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos , Retinoblastoma/genética , Retinoblastoma/patologia , Serina-Treonina Quinases TOR/biossíntese , Ensaios Antitumorais Modelo de Xenoenxerto
13.
Exp Eye Res ; 124: 67-73, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24837142

RESUMO

Verteporfin (VP), a benzoporphyrin derivative, is clinically used in photodynamic therapy for neovascular macular degeneration. Recent studies indicate that VP may inhibit growth of hepatoma cells without photoactivation through inhibition of YAP-TEAD complex. In this study, we examined the effects of VP without light activation on human retinoblastoma cell lines. Verteporfin but not vehicle control inhibited the growth, proliferation and viability of human retinoblastoma cell lines (Y79 and WERI) in a dose-dependent manner and was associated with downregulation of YAP-TEAD associated downstream proto-oncogenes such as c-myc, Axl, and surviving. In addition VP affected signals involved in cell migration and angiogenesis such as CTGF, cyr61, and VEGF-A but was not associated with significant effect on the mTOR/autophagy pathway. Of interest the pluripotency marker Oct4 were downregulated by Verteporfin treatment. Our results indicate that the clinically used photosensitizer VP is a potent inhibitor of cell growth in retinoblastoma cells, disrupting YAP-TEAD signaling and pluripotential marker OCT4. This study highlights for the first time the role of the YAP-TEAD pathway in Retinoblastoma and suggests that VP may be a useful adjuvant therapeutic tool in treating Rb patients.


Assuntos
Fotoquimioterapia/métodos , Porfirinas/uso terapêutico , Retina/patologia , Neoplasias da Retina/tratamento farmacológico , Retinoblastoma/tratamento farmacológico , Proliferação de Células/efeitos dos fármacos , Pré-Escolar , Relação Dose-Resposta a Droga , Seguimentos , Humanos , Lactente , Recém-Nascido , Fármacos Fotossensibilizantes/administração & dosagem , Fármacos Fotossensibilizantes/uso terapêutico , Porfirinas/administração & dosagem , Retina/efeitos dos fármacos , Neoplasias da Retina/patologia , Retinoblastoma/patologia , Células Tumorais Cultivadas , Verteporfina
14.
Invest Ophthalmol Vis Sci ; 55(7): 4175-85, 2014 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-24781943

RESUMO

PURPOSE: To evaluate the effects and mechanism of aminoimidazole carboxamide ribonucleotide (AICAR), an AMP-dependent kinase (AMPK) activator, on the growth of uveal melanoma cell lines. METHODS: Four different cell lines were treated with AICAR (1-4 mM). Cell growth was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium (MTT) assay. Cell cycle analysis was conducted by flow cytometry; additionally, expression of cell-cycle control proteins, cell growth transcription factors, and downstream effectors of AMPK were determined by RT-PCR and Western blot. RESULTS: Aminoimidazole carboxamide ribonucleotide inhibited cell growth, induced S-phase arrest, and led to AMPK activation. Aminoimidazole carboxamide ribonucleotide treatment was associated with inhibition of eukaryotic translation initiation factor 4E-BP1 phosphorylation, a marker of mammalian target of rapamycin (mTOR) pathway activity. Aminoimidazole carboxamide ribonucleotide treatment was also associated with downregulation of cyclins A and D, but had minimal effects on the phosphorylation of ribosomal protein S6 or levels of the macroautophagy marker LC3B. The effects of AICAR were abolished by treatment with dipyridamole, an adenosine transporter inhibitor that blocks the entry of AICAR into cells. Treatment with adenosine kinase inhibitor 5-iodotubericidin, which inhibits the conversion of AICAR to its 5'-phosphorylated ribotide 5-aminoimidazole-4-carboxamide-1-D-ribofuranosyl-5'-monophosphate (ZMP; the direct activator of AMPK), reversed most of the growth-inhibitory effects, indicating that some of AICAR's antiproliferative effects are mediated at least partially through AMPK activation. CONCLUSIONS: Aminoimidazole carboxamide ribonucleotide inhibited uveal melanoma cell proliferation partially through activation of the AMPK pathway and downregulation of cyclins A1 and D1.


Assuntos
Aminoimidazol Carboxamida/análogos & derivados , Ativação Enzimática/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica , Melanoma/genética , Fosfotransferases (Aceptor do Grupo Fosfato)/metabolismo , RNA Neoplásico/genética , Ribonucleotídeos/farmacologia , Serina-Treonina Quinases TOR/genética , Neoplasias Uveais/genética , Aminoimidazol Carboxamida/farmacologia , Western Blotting , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Citometria de Fluxo , Humanos , Melanoma/tratamento farmacológico , Melanoma/enzimologia , Fosfotransferases (Aceptor do Grupo Fosfato)/efeitos dos fármacos , Reação em Cadeia da Polimerase em Tempo Real , Serina-Treonina Quinases TOR/metabolismo , Neoplasias Uveais/tratamento farmacológico , Neoplasias Uveais/enzimologia
15.
PLoS One ; 9(3): e91849, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24647208

RESUMO

EGFL7 is a secreted angiogenic factor, which in contrast to the well-known secreted angiogenic molecules VEGF and FGF-2, is almost exclusively expressed by endothelial cells and may act in an autocrine fashion. Prior studies have shown EGFL7 to mediate its angiogenic effects by interfering with the Notch pathway and/or via the intronic miR126. Less is known about its effects on VEGF signaling. We wanted to investigate the role of epidermal growth factor-like domain 7 (EGFL7) in VEGF-driven angiogenesis using an ex vivo Matrigel-embedded mouse eye cup assay and siRNA mediated knockdown of EGFL7 by siRNA. Our results suggested that VEGF-induced vascular tube formation was significantly impaired after siRNA downregulation of EGFL7. In addition, knockdown of EGFL7 suppressed VEGF upregulation of phospho-Akt and phospho-Erk(1/2) in endothelial cells, but did not alter VEGFR phosphorylation and neuropilin-1 protein expression or miR126 expression. Thus, in conclusion, EGFL7 is required for VEGF upregulation of the Akt/Erk (1/2) pathway during angiogenesis, and may represent a new therapeutic target in diseases of pathological neovascularization.


Assuntos
Bioensaio , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Técnicas In Vitro , Neovascularização Fisiológica/efeitos dos fármacos , Proteínas/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fator A de Crescimento do Endotélio Vascular/farmacologia , Animais , Proteínas de Ligação ao Cálcio , Família de Proteínas EGF , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/enzimologia , Ativação Enzimática/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Camundongos Endogâmicos C57BL , Neuropilina-1/metabolismo , Fosforilação/efeitos dos fármacos , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo
16.
PLoS One ; 8(1): e52852, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23300996

RESUMO

5-Aminoimidazole-4-carboxamide-1-ß-4-ribofuranoside (AICAR), an analog of AMP is widely used as an activator of AMP-kinase (AMPK), a protein that regulates the responses of the cell to energy change. Recently, we showed that AICAR-induced AMPK activation inhibits the growth of retinoblastoma cells in vitro by decreasing cyclins and by inducing apoptosis and S-phase arrest. In this study, we investigated the effects of AMPK activator AICAR on the growth of retinoblastoma in vivo. Intraperitoneal injection of AICAR resulted in 48% growth inhibition of Y79 retinoblastoma cell tumors in mice. Tumors isolated from mice treated with AICAR had decreased expression of Ki67 and increased apoptotic cells (TUNEL positive) compared with the control. In addition, AICAR treatment suppressed significantly tumor vessel density and macrophage infiltration. We also showed that AICAR administration resulted in AMPK activation and mTOR pathway inhibition. Paradoxically observed down-regulation of p21, which indicates that p21 may have a novel function of an oncogene in retinoblastoma tumor. Our results indicate that AICAR treatment inhibited the growth of retinoblastoma tumor in vivo via AMPK/mTORC1 pathway and by apoptogenic, anti-proliferative, anti-angiogenesis mechanism. AICAR is a promising novel non-chemotherapeutic drug that may be effective as an adjuvant in treating Retinoblastoma.


Assuntos
Aminoimidazol Carboxamida/análogos & derivados , Antineoplásicos/farmacologia , Apoptose , Neovascularização Patológica/tratamento farmacológico , Retinoblastoma/tratamento farmacológico , Ribonucleotídeos/farmacologia , Aminoimidazol Carboxamida/metabolismo , Aminoimidazol Carboxamida/farmacologia , Animais , Ciclo Celular , Linhagem Celular Tumoral , Proliferação de Células , Ciclinas/metabolismo , Camundongos , Camundongos Nus , Transplante de Neoplasias , Ribonucleotídeos/metabolismo , Fase S
17.
Proc Natl Acad Sci U S A ; 109(7): 2388-93, 2012 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-22308397

RESUMO

The differentiation of cilia is mediated by kinesin-driven transport. As the function of kinesins in vertebrate ciliogenesis is poorly characterized, we decided to determine the role of kinesin-2 family motors--heterotrimeric kinesin-II and the homodimeric Kif17 kinesin--in zebrafish cilia. We report that kif17 is largely dispensable for ciliogenesis; kif17 homozygous mutant animals are viable and display subtle morphological defects of olfactory cilia only. In contrast to that, the kif3b gene, encoding a heterotrimeric kinesin subunit, is necessary for cilia differentiation in most tissues, although exceptions exist, and include photoreceptors and a subset of hair cells. Cilia of these cell types persist even in kif3b/kif17 double mutants. Although we have not observed a functional redundancy of kif3b and kif17, kif17 is able to substitute for kif3b in some cilia. In contrast to kif3b/kif17 double mutants, simultaneous interference with kif3b and kif3c leads to the complete loss of photoreceptor and hair cell cilia, revealing redundancy of function. This is in agreement with the idea that Kif3b and Kif3c motor subunits form complexes with Kif3a, but not with each other. Interestingly, kif3b mutant photoreceptor cilia differentiate with a delay, suggesting that kif3c, although redundant with kif3b at later stages of differentiation, is not active early in photoreceptor ciliogenesis. Consistent with that, the overexpression of kif3c in kif3b mutants rescues early photoreceptor cilia defects. These data reveal unexpected diversity of functional relationships between vertebrate ciliary kinesins, and show that the repertoire of kinesin motors changes in some cilia during their differentiation.


Assuntos
Cílios , Cinesinas/metabolismo , Cinesinas/fisiologia , Animais , Sequência de Bases , Primers do DNA , Homozigoto , Imuno-Histoquímica , Cinesinas/genética , Mutação , Reação em Cadeia da Polimerase , Peixe-Zebra
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