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1.
FASEB J ; 38(5): e23533, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38451430

RESUMO

Rubeosis Iridis (RI) is characterized by an increase in neovascularization and inflammation factors in the iris. During angiogenesis, the urokinase plasminogen activator (uPA) and its receptor (uPAR) play a pivotal role in extracellular matrix remodeling, where uPAR regulates endothelial cell migration and proliferation through assembly with transmembrane receptors. Here, in the context of hypoxia-induced angiogenesis, the uPA/uPAR system blockage was investigated by using UPARANT in a novel ex vivo human iris organotypic angiogenesis assay. The effects of uPA/uPAR system antagonism in the humanized model of ocular pathologic angiogenesis were analyzed by sprouting angiogenesis and protein assays (western, dot blots, and co-immunoprecipitation) and correlated to vascular endothelial growth factor (VEGF) inhibition. Phosphoprotein and co-immunoprecipitation assay illustrated an unidentified antagonism of UPARANT in the interaction of uPAR with the low-density lipoprotein receptor-related protein-1 (LRP-1), resulting in inhibition of ß-catenin-mediated angiogenesis in this model. The effects of uPA/uPAR system inhibition were focal to endothelial cells ex vivo. Comparison between human iris endothelial cells and human retinal endothelial revealed an endothelial-specific mechanism of ß-catenin-mediated angiogenesis inhibited by uPA/uPAR system blockage and not by VEGF inhibition. Collectively, these findings broaden the understanding of the effects of the uPA/uPAR system antagonism in the context of angiogenesis, revealing non-canonical ß-catenin downstream effects mediated by LRP-1/uPAR interaction.


Assuntos
Células Endoteliais , Fator A de Crescimento do Endotélio Vascular , Humanos , beta Catenina , Angiogênese , Iris
2.
Heliyon ; 10(1): e23831, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38332874

RESUMO

Retinoblastoma is an eye cancer that commonly affects young children. Despite significant advances, current treatments cause side effects even when administered locally, and patients may still have to undergo enucleation. This is particularly disheartening in cases of bilateral retinoblastoma. Hence, there is an urgent need for novel therapeutic strategies. Inhibitors of the enzyme dihydroorotate dehydrogenase (DHODH), which is involved in the de novo pyrimidine ribonucleotide synthesis pathway, have proven to be effective in preclinical trials against several cancers including pediatric cancers. Here we tested whether blocking pyrimidine ribonucleotide synthesis promotes retinoblastoma cell death. Cultured retinoblastoma cell lines were treated with small molecule inhibitors of DHODH alone or in combination with inhibitors of nucleoside uptake to also block the salvage pathway for pyrimidine ribonucleotide formation. On their own, DHODH inhibitors had a moderate killing effect. However, the combination with nucleoside uptake inhibitors greatly enhanced the effect of DHODH inhibition. In addition, we observed that pyrimidine ribonucleotide synthesis blockage can cause cell death in a p53 mutant retinoblastoma cell line derived from a patient with metastasis. Explaining these results, the analysis of a published patient cohort revealed that loss of chr16q22.2 (containing the DHODH gene) is amongst the most frequent alterations in retinoblastoma and that these tumors often show gains in chromosome regions expressing pyrimidine ribonucleotide salvage factors. Furthermore, these genome alterations associate with malignancy. These results indicate that targeting pyrimidine ribonucleotide synthesis may be an effective therapeutic strategy to consider as a treatment for retinoblastoma.

3.
Can J Ophthalmol ; 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38219791

RESUMO

OBJECTIVE: To examine the prognostic implication of tenascin C (TNC) in posterior uveal melanoma (UM). DESIGN: Retrospective cohort study. PARTICIPANTS: A total of 162 patients diagnosed with posterior UM. METHODS: A peripheral blood sample was obtained from 82 patients at the time of UM diagnosis between 1996 and 1999. Samples were kept frozen at -80°C until the concentration of TNC was measured in 2021. Primary tumour TNC RNA sequencing data were collected from another 80 patients (The Cancer Genome Atlas cohort). Patients were separated based on median TNC values. Cumulative incidences of metastatic death (UM mortality) from competing risks data were calculated as well as Cox regression hazard ratios. RESULTS: Patients with high and low TNC levels had tumours of similar size and American Joint Committee on Cancer stage at Bonferroni-corrected significance levels. The exception was a significantly smaller tumour diameter in patients with high serum TNC levels (p = 0.003). In competing risks analysis, patients with high serum TNC levels (≥7 ng/mL) had a higher UM mortality rate (44% vs 17% at 20 years; p = 0.008). Similarly, patients with higher primary tumour TNC RNA levels (≥1 transcripts per million) had higher UM mortality (83% vs 27% at 5 years; p = 0.003). In multivariate Cox regressions, TNC levels in peripheral blood and primary tumours were predictors of metastatic death independent of American Joint Committee on Cancer stage. CONCLUSIONS: TNC is a prognostic biomarker in UM. At the time of primary tumour diagnosis, it is measured in higher levels in both peripheral blood and tumour tissue from patients who will eventually suffer from metastatic death.

4.
Br J Ophthalmol ; 108(4): 578-587, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-37028917

RESUMO

BACKGROUND: Metabolic factors and obesity may influence the development and progression of cancer. In this study, we examine their association with the risk of developing metastases of uveal melanoma. METHODS: Data on metabolic factors, medications, serum leptin levels, tumour leptin receptor RNA expression and clinical outcomes were examined in three cohorts. HRs for metastasis and cumulative incidences of melanoma-related mortality were calculated, and the levels of tumour leptin receptor expression were compared with prognostic factors including BAP1 mutation, and tumour cell morphology. RESULTS: Of 581 patients in the main cohort, 116 (20%) were obese and 7 (1 %) had metastatic disease at presentation. In univariate Cox regressions, tumour diameter, diabetes type II and use of insulin were associated with metastases, but patients with obesity had a lower risk. The beneficial prognostic implication of obesity was retained in multivariate regressions. In competing risk analyses, the incidence of melanoma-related mortality was significantly lower for patients with obesity. Serum leptin levels≥median were associated with a reduced risk for metastasis, independent of patient sex and cancer stage in a separate cohort (n=80). Similarly, in a third cohort (n=80), tumours with BAP1 mutation and epithelioid cells had higher leptin receptor RNA expression levels, which have a negative correlation with serum leptin levels. CONCLUSION: Obesity and elevated serum leptin levels are associated with a lower risk for developing metastases and dying from uveal melanoma.


Assuntos
Melanoma , Neoplasias Uveais , Humanos , Melanoma/patologia , Leptina , Índice de Massa Corporal , Paradoxo da Obesidade , Receptores para Leptina/genética , Proteínas Supressoras de Tumor , Neoplasias Uveais/patologia , Prognóstico , Obesidade/complicações , RNA
5.
Mol Nutr Food Res ; 68(3): e2200623, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38044285

RESUMO

SCOPE: Our laboratory has previously described the antioxidant and anti-inflammatory potential of a wild olive (acebuche, ACE) oil against hypertension-associated vascular retinopathies. The current study aims to analyze the antifibrotic effect of ACE oil on the retina of hypertensive mice. METHODS AND RESULTS: Mice are rendered hypertensive by administration of NG-nitro-L-arginine-methyl-ester (L-NAME) and simultaneously subjected to dietary supplementation with ACE oil or a reference extra virgin olive oil (EVOO). Intraocular pressure (IOP) is measured by rebound tonometry, and retinal vasculature/layers are analyzed by fundus fluorescein angiography and optical coherence tomography. Different fibrosis-related parameters are analyzed in the retina and choroid of normotensive and hypertensive mice with or without oil supplementation. Besides preventing the alterations found in hypertensive animals, including increased IOP, reduced fluorescein signal, and altered retinal layer thickness, the ACE oil-enriched diet improves collagen metabolism by regulating the expression of major fibrotic process modulators (matrix metalloproteinases, tissue inhibitors of metalloproteinases, connective tissue growth factor, and transforming growth factor beta family). CONCLUSION: Regular consumption of EVOO and ACE oil (with better outcomes in the latter) might help reduce abnormally high IOP values in the context of hypertension-related retinal damage, with significant reduction in the surrounding fibrotic process.


Assuntos
Hipertensão , Hipertensão Ocular , Camundongos , Animais , Hipertensão/prevenção & controle , Antioxidantes/metabolismo , Azeite de Oliva/farmacologia , Hipertensão Ocular/prevenção & controle , Fibrose , Retina/metabolismo
6.
J Biol Eng ; 17(1): 58, 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37749603

RESUMO

A number of molecular biofactors have been documented in pathogenesis and poor prognosis of colorectal cancer (CRC). Among them, the Hypoxia-Inducible Factor (HIF-1a) is frequently reported to become over-expressed, and its targeting could restrict and control a variety of essential hallmarks of CRC. Niosomes are innovative drug delivery vehicles with the encapsulating capacity for co-loading both hydrophilic and hydrophobic drugs at the same time. Also, they can enhance the local accumulation while minimizing the dose and side effects of drugs. YC-1 and PX-12 are two inhibitors of HIF-1a. The purpose of this work was to synthesize dual-loaded YC-1 and PX-12 niosomes to efficiently target HIF-1α in CRC, HT-29 cells. The niosomes were prepared by the thin-film hydration method, then the niosomal formulation of YC-1 and PX-12 (NIO/PX-YC) was developed and optimized by the central composition method (CCD) using the Box-Behnken design in terms of size, polydispersity index (PDI), entrapment efficiency (EE). Also, they are characterized by DLS, FESEM, and TEM microscopy, as well as FTIR spectroscopy. Additionally, entrapment efficiency, in vitro drug release kinetics, and stability were assessed. Cytotoxicity, apoptosis, and cell cycle studies were performed after the treatment of HT-29 cells with NIO/PX-YC. The expression of HIF-1αat both mRNA and protein levels were studied after NIO/PX-YC treatment. The prepared NIO/PX-YC showed a mean particle size of 185 nm with a zeta potential of about-7.10 mv and a spherical morphology. Also, PX-12 and YC-1 represented the entrapment efficiency of about %78 and %91, respectively, with a sustainable and controllable release. The greater effect of NIO/PX-YC than the free state of PX-YC on the cell survival rate, cell apoptosis, and HIF-1α gene/protein expression were detected (p < 0.05). In conclusion, dual loading of niosomes with YC-1 and PX-12 enhanced the effect of drugs on HIF-1α inhibition, thus boosting their anticancer effects.

7.
BMC Cancer ; 23(1): 277, 2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-36973672

RESUMO

PURPOSE: To develop a prognostic test based on a single blood sample obtained at the time of uveal melanoma diagnosis. METHODS: 83 patients diagnosed with posterior uveal melanoma between 1996 and 2000 were included. Peripheral serum samples were obtained at diagnosis and kept at -80 °C until this analysis. Protein profiling of 84 cancer-related proteins was used to screen for potential biomarkers and a prognostic test that stratifies patients into metastatic risk categories was developed (serUM-Px) in a training cohort and then tested in a validation cohort. RESULTS: Low serum leptin levels and high osteopontin levels were found to identify patients with poor prognosis and were therefore selected for inclusion in the final test. In the validation cohort, patient sex and American Joint Committee on Cancer stages were similarly distributed between the low, intermediate, and high metastatic risk categories. With increasing metastatic risk category, patients had shorter metastasis-free- and overall survival, as well as greater cumulative incidence of uveal melanoma-related mortality in competing risk analysis (P = 0.007, 0.018 and 0.029, respectively). In multivariate Cox regression, serUM-Px was an independent predictor of metastasis with tumor size and patient sex as covariates (hazard ratio 3.2, 95% CI 1.5-6.9). CONCLUSIONS: A prognostic test based on a single peripheral venous blood sample at the time of uveal melanoma diagnosis stratifies patients into low, intermediate, and high metastatic risk categories. Prospective validation will facilitate its clinical utility.


Assuntos
Neoplasias Uveais , Humanos , Taxa de Sobrevida , Prognóstico , Neoplasias Uveais/patologia , Proteínas Sanguíneas
8.
Mol Ther ; 31(3): 825-846, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36638800

RESUMO

Blindness caused by advanced stages of inherited retinal diseases and age-related macular degeneration are characterized by photoreceptor loss. Cell therapy involving replacement with functional photoreceptor-like cells generated from human pluripotent stem cells holds great promise. Here, we generated a human recombinant retina-specific laminin isoform, LN523, and demonstrated the role in promoting the differentiation of human embryonic stem cells into photoreceptor progenitors. This chemically defined and xenogen-free method enables reproducible production of photoreceptor progenitors within 32 days. We observed that the transplantation into rd10 mice were able to protect the host photoreceptor outer nuclear layer (ONL) up to 2 weeks post transplantation as measured by full-field electroretinogram. At 4 weeks post transplantation, the engrafted cells were found to survive, mature, and associate with the host's rod bipolar cells. Visual behavioral assessment using the water maze swimming test demonstrated visual improvement in the cell-transplanted rodents. At 20 weeks post transplantation, the maturing engrafted cells were able to replace the loss of host ONL by extensive association with host bipolar cells and synapses. Post-transplanted rabbit model also provided congruent evidence for synaptic connectivity with the degenerated host retina. The results may pave the way for the development of stem cell-based therapeutics for retina degeneration.


Assuntos
Células-Tronco Pluripotentes , Degeneração Retiniana , Humanos , Camundongos , Animais , Coelhos , Laminina/genética , Retina , Células Fotorreceptoras , Degeneração Retiniana/genética , Degeneração Retiniana/terapia , Diferenciação Celular
9.
Stem Cell Reports ; 17(6): 1458-1475, 2022 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-35705015

RESUMO

Human embryonic stem cell-derived retinal pigment epithelial cells (hESC-RPE) are a promising cell source to treat age-related macular degeneration (AMD). Despite several ongoing clinical studies, a detailed mapping of transient cellular states during in vitro differentiation has not been performed. Here, we conduct single-cell transcriptomic profiling of an hESC-RPE differentiation protocol that has been developed for clinical use. Differentiation progressed through a culture diversification recapitulating early embryonic development, whereby cells rapidly acquired a rostral embryo patterning signature before converging toward the RPE lineage. At intermediate steps, we identified and examined the potency of an NCAM1+ retinal progenitor population and showed the ability of the protocol to suppress non-RPE fates. We demonstrated that the method produces a pure RPE pool capable of maturing further after subretinal transplantation in a large-eyed animal model. Our evaluation of hESC-RPE differentiation supports the development of safe and efficient pluripotent stem cell-based therapies for AMD.


Assuntos
Células-Tronco Embrionárias Humanas , Degeneração Macular , Animais , Diferenciação Celular/genética , Humanos , Degeneração Macular/genética , Degeneração Macular/terapia , Epitélio Pigmentado da Retina , Pigmentos da Retina
10.
Foods ; 10(9)2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34574102

RESUMO

Inflammation plays a crucial role in the course of eye diseases, including many vascular retinopathies. Although olive oil is known to have beneficial effects against inflammatory processes, there is no information available on the anti-inflammatory potential of the wild olive tree (namely, acebuche (ACE) for the primitive Spanish lineages). Here we investigate the anti-inflammatory effects of ACE oil in the retina of a mouse model of arterial hypertension, which was experimentally induced by administration of L-NAME (NG-nitro-L-arginine-methyl-ester). The animals were fed supplements of ACE oil or extra virgin olive oil (EVOO, for comparative purposes). Retinal function was assessed by electroretinography (ERG), and different inflammation-related parameters were measured in the retina and choroid. Besides significant prevention of retinal dysfunction shown in ERG recordings, ACE oil-enriched diet upregulated the expression of the anti-inflammatory markers PPARγ, PPARα and IL-10, while reducing that of major proinflammatory biomarkers, IL-1ß, IL-6, TNF-α and COX-2. This is the first report to highlight the anti-inflammatory properties of an ACE oil-enriched diet against hypertension-related retinal damage. Noteworthy, dietary supplementation with ACE oil yielded better results compared to a reference EVOO.

11.
Acta Ophthalmol ; 99(8): e1255-e1262, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33729690

RESUMO

Ocular neovascular diseases, such as proliferative diabetic retinopathy, retinopathy of prematurity and neovascular age-related macular degeneration, are the leading causes of visual impairment worldwide. The hypoxia-inducible factors and vascular endothelial growth factors are key molecular promoters of ocular neovascularization. Moreover, the role of microRNAs as regulators of angiogenesis has been expanding, particularly hypoxia-associated microRNA; hypoxamiRs. This review provides a summary of hypoxamiRs that directly and specifically target HIF1A and VEGF mRNAs, thus critically involved in the regulation of ocular neovascular pathologies. The discussed microRNAs highlight putative diagnostic markers and therapeutic agents in choroidal and retinal angiogenic diseases, including proliferative diabetic retinopathy, retinopathy of prematurity and neovascular age-related macular degeneration.


Assuntos
Neovascularização de Coroide/genética , Regulação da Expressão Gênica , Fator 1 Induzível por Hipóxia/genética , MicroRNAs/genética , Neovascularização Retiniana/genética , Fator A de Crescimento do Endotélio Vascular/genética , Animais , Neovascularização de Coroide/metabolismo , Humanos , Fator 1 Induzível por Hipóxia/biossíntese , Neovascularização Retiniana/metabolismo , Fator A de Crescimento do Endotélio Vascular/biossíntese
12.
Exp Eye Res ; 206: 108518, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33639134

RESUMO

BACKGROUND: Echinomycin (EKN), an inhibitor of hypoxia-inducible factor (HIF)-1 DNA-binding activity, has been implied as a possible therapeutic agent in ischemic diseases. Here, we assess EKN in hypoxia-driven responses in vitro using human primary adult retinal pigment epithelium cells (aRPE) and retinal endothelial cells (hREC), and in vivo using the laser-induced mouse choroidal neovascularization (CNV) model. METHODS: Effects of EKN on hypoxia-mediated pathways in aRPE were analyzed by Western blotting for HIF-1α protein, quantitative PCR of HIF-target genes, and proteome array for soluble angiogenic factors. In vitro inhibition of angiogenesis by EKN was determined in hREC. In vivo inhibition of angiogenesis by EKN was determined in the mouse laser-induced CNV, as a model of HIF-associated ocular neovascularization. CNV lesion area was determined by fundus fluorescein angiography. RESULTS: aRPE treated with EKN showed hypoxia-dependent significantly decreased cell recovery in the wound healing assay. These results were supported by lower levels of HIF-mediated transcripts detected in hypoxic aRPE cells treated with EKN compared with non-treated controls, and confirmed by proteome profiler for angiogenic factors. hREC exposed to aRPE EKN-conditioned medium displayed reduced sprouting angiogenesis. Mice with laser-induced CNV treated with intravitreally injected EKN showed significantly decreased vascular lesion area when compared with a mouse equivalent of aflibercept, or vehicle-treated controls. CONCLUSIONS: Our data proposes EKN as a potent inhibitor of HIF-mediated angiogenesis in retinal cells and in the mouse model of CNV, which could have future implications in the treatment of patients with neovascular age-related macular degeneration.


Assuntos
Neovascularização de Coroide/tratamento farmacológico , Equinomicina/farmacologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Epitélio Pigmentado da Retina/metabolismo , Adulto , Células Cultivadas , Neovascularização de Coroide/metabolismo , Angiofluoresceinografia , Fundo de Olho , Humanos , Epitélio Pigmentado da Retina/patologia , Transdução de Sinais
13.
J Cell Physiol ; 2020 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-33090510

RESUMO

Cornea is an avascular and transparent tissue that focuses light on retina. Cornea is supported by the corneal-endothelial layer through regulation of hydration homeostasis. Restoring vision in patients afflicted with corneal endothelium dysfunction-mediated blindness most often requires corneal transplantation (CT), which faces considerable constrictions due to donor limitations. An emerging alternative to CT is corneal endothelium tissue engineering (CETE), which involves utilizing scaffold-based methods and scaffold-free strategies. The innovative scaffold-free method is cell sheet engineering, which typically generates cell layers surrounded by an intact extracellular matrix, exhibiting tunable release from the stimuli-responsive surface. In some studies, scaffold-based or scaffold-free technologies have been reported to achieve promising outcomes. However, yet some issues exist in translating CETE from bench to clinical practice. In this review, we compare different corneal endothelium regeneration methods and elaborate on the application of multiple cell types (stem cells, corneal endothelial cells, and endothelial precursors), signaling molecules (growth factors, cytokines, chemical compounds, and small RNAs), and natural and synthetic scaffolds for CETE. Furthermore, we discuss the importance of three-dimensional bioprinting strategies and simulation of Descemet's membrane by biomimetic topography. Finally, we dissected the recent advances, applications, and prospects of cell sheet engineering for CETE.

14.
Antioxidants (Basel) ; 9(9)2020 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-32961933

RESUMO

Oxidative stress plays an important role in the pathogenesis of ocular diseases, including hypertensive eye diseases. The beneficial effects of olive oil on cardiovascular diseases might rely on minor constituents. Currently, very little is known about the chemical composition and/or therapeutic effects of the cultivated olive tree's counterpart, wild olive (also known in Spain as acebuche-ACE). Here, we aimed to analyze the antioxidant and retinoprotective effects of ACE oil on the eye of hypertensive mice made hypertensive via administration of NG-nitro-L-arginine-methyl-ester (L-NAME), which were subjected to a dietary supplementation with either ACE oil or extra virgin olive oil (EVOO) for comparison purposes. Deep analyses of major and minor compounds present in both oils was accompanied by blood pressure monitoring, morphometric analyses, as well as different determinations of oxidative stress-related parameters in retinal layers. Aside from its antihypertensive effect, an ACE oil-enriched diet reduced NADPH (nicotinamide adenine dinucleotide phosphate) oxidase activity/gene/protein expression (with a major implication of NADPH oxidase (NOX)2 isoform) in the retinas of hypertensive mice. Supplementation with ACE oil in hypertensive animals also improved alterations in nitric oxide bioavailability and in antioxidant enzyme profile. Interestingly, our findings show that the use of ACE oil resulted in better outcomes, compared with reference EVOO, against hypertension-related oxidative retinal damage.

15.
J Mol Med (Berl) ; 98(11): 1629-1638, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32940719

RESUMO

Proliferative retinopathies (PR) lead to an increase in neovascularization and inflammation factors, at times culminating in pathologic rubeosis iridis (RI). In mice, uveal puncture combined with injection of hypoxia-conditioned media mimics RI associated with proliferative retinopathies. Here, we investigated the effects of the urokinase plasminogen activator receptor (uPAR) antagonist-UPARANT-on the angiogenic and inflammatory processes that are dysregulated in this model. In addition, the effects of UPARANT were compared with those of anti-vascular endothelial growth factor (VEGF) therapies. Administration of UPARANT promptly decreased iris vasculature, while anti-VEGF effects were slower and less pronounced. Immunoblot and qPCR analysis suggested that UPARANT acts predominantly by reducing the upregulated inflammatory and extracellular matrix degradation responses. UPARANT appears to be more effective in comparison to anti-VEGF in the treatment of RI associated with PR in the murine model, by modulating multiple uPAR-associated signaling pathways. Furthermore, UPARANT effectiveness was maintained when systemically administered, which could open to novel improved therapies for proliferative ocular diseases, particularly those associated with PR. KEY MESSAGES: • Further evidence of UPARANT effectiveness in normalizing pathological iris neovascularization. • Both systemic and local administration of UPARANT reduce iris neovascularization in a model associated with proliferative retinopathies. • In the mouse models of rubeosis iridis associated with proliferative retinopathy, UPARANT displays stronger effects when compared with anti-vascular endothelial growth factor regimen.


Assuntos
Inibidores da Angiogênese/farmacologia , Oligopeptídeos/farmacologia , Doenças Retinianas/etiologia , Doenças Retinianas/metabolismo , Animais , Anti-Inflamatórios/farmacologia , Retinopatia Diabética , Modelos Animais de Doenças , Matriz Extracelular/metabolismo , Humanos , Imuno-Histoquímica , Camundongos , Doenças Retinianas/tratamento farmacológico , Doenças Retinianas/patologia , Neovascularização Retiniana/tratamento farmacológico , Neovascularização Retiniana/etiologia , Neovascularização Retiniana/metabolismo , Neovascularização Retiniana/patologia
16.
Nat Commun ; 11(1): 1609, 2020 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-32231223

RESUMO

In vitro differentiation of human pluripotent stem cells into functional retinal pigment epithelial (RPE) cells provides a potentially unlimited source for cell based reparative therapy of age-related macular degeneration. Although the inherent pigmentation of the RPE cells have been useful to grossly evaluate differentiation efficiency and allowed manual isolation of pigmented structures, accurate quantification and automated isolation has been challenging. To address this issue, here we perform a comprehensive antibody screening and identify cell surface markers for RPE cells. We show that these markers can be used to isolate RPE cells during in vitro differentiation and to track, quantify and improve differentiation efficiency. Finally, these surface markers aided to develop a robust, direct and scalable monolayer differentiation protocol on human recombinant laminin-111 and -521 without the need for manual isolation.


Assuntos
Biomarcadores/metabolismo , Diferenciação Celular/fisiologia , Células Epiteliais/metabolismo , Neurônios/metabolismo , Pigmentos da Retina/metabolismo , Animais , Antígeno CD56 , Células-Tronco Embrionárias , Humanos , Laminina/genética , Degeneração Macular/metabolismo , Coelhos , Epitélio Pigmentado da Retina/metabolismo
17.
Stem Cells Transl Med ; 9(8): 936-953, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32319201

RESUMO

As pluripotent stem cell (PSC)-based reparative cell therapies are reaching the bedside, there is a growing need for the standardization of studies concerning safety of the derived products. Clinical trials using these promising strategies are in development, and treatment for age-related macular degeneration is one of the first that has reached patients. We have previously established a xeno-free and defined differentiation protocol to generate functional human embryonic stem cells (hESCs)-derived retinal pigment epithelial (RPE) cells. In this study, we perform preclinical safety studies including karyotype and whole-genome sequencing (WGS) to assess genome stability, single-cell RNA sequencing to ensure cell purity, and biodistribution and tumorigenicity analysis to rule out potential migratory or tumorigenic properties of these cells. WGS analysis illustrates that existing germline variants load is higher than the introduced variants acquired through in vitro culture or differentiation, and enforces the importance to examine the genome integrity at a deeper level than just karyotype. Altogether, we provide a strategy for preclinical evaluation of PSC-based therapies and the data support safety of the hESC-RPE cells generated through our in vitro differentiation methodology.


Assuntos
Células-Tronco Embrionárias Humanas/metabolismo , Degeneração Macular/terapia , Células-Tronco Pluripotentes/metabolismo , Idoso , Diferenciação Celular , Células-Tronco Embrionárias Humanas/citologia , Humanos , Células-Tronco Pluripotentes/citologia
18.
Stem Cell Reports ; 14(4): 648-662, 2020 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-32197113

RESUMO

Human embryonic stem cell-derived retinal pigment epithelial (hESC-RPE) cells could serve as a replacement therapy in advanced stages of age-related macular degeneration. However, allogenic hESC-RPE transplants trigger immune rejection, supporting a strategy to evade their immune recognition. We established single-knockout beta-2 microglobulin (SKO-B2M), class II major histocompatibility complex transactivator (SKO-CIITA) and double-knockout (DKO) hESC lines that were further differentiated into corresponding hESC-RPE lines lacking either surface human leukocyte antigen class I (HLA-I) or HLA-II, or both. Activation of CD4+ and CD8+ T-cells was markedly lower by hESC-RPE DKO cells, while natural killer cell cytotoxic response was not increased. After transplantation of SKO-B2M, SKO-CIITA, or DKO hESC-RPEs in a preclinical rabbit model, donor cell rejection was reduced and delayed. In conclusion, we have developed cell lines that lack both HLA-I and -II antigens, which evoke reduced T-cell responses in vitro together with reduced rejection in a large-eyed animal model.


Assuntos
Células Epiteliais/metabolismo , Antígenos de Histocompatibilidade Classe II/metabolismo , Antígenos de Histocompatibilidade Classe I/metabolismo , Células-Tronco Embrionárias Humanas/citologia , Epitélio Pigmentado da Retina/citologia , Proteína 9 Associada à CRISPR/metabolismo , Sistemas CRISPR-Cas/genética , Citotoxicidade Imunológica , Xenoenxertos , Células-Tronco Embrionárias Humanas/metabolismo , Humanos , Imunomodulação , Proteínas Nucleares/metabolismo , Polimorfismo de Nucleotídeo Único/genética , Linfócitos T/metabolismo , Transativadores/metabolismo , Microglobulina beta-2/metabolismo
19.
Cell Mol Life Sci ; 77(5): 819-833, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31893312

RESUMO

Understanding the mechanisms that underlie age-related macular degeneration (AMD) has led to the identification of key molecules. Hypoxia-inducible transcription factors (HIFs) have been associated with choroidal neovascularization and the progression of AMD into the neovascular clinical phenotype (nAMD). HIFs regulate the expression of multiple growth factors and cytokines involved in angiogenesis and inflammation, hallmarks of nAMD. This knowledge has propelled the development of a new group of therapeutic strategies focused on gene therapy. The present review provides an update on current gene therapies in ocular angiogenesis, particularly nAMD, from both basic and clinical perspectives.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Terapia Genética/métodos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Degeneração Macular/genética , Degeneração Macular/terapia , Proteínas Repressoras/metabolismo , Proteínas Reguladoras de Apoptose/antagonistas & inibidores , Proteínas Reguladoras de Apoptose/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/antagonistas & inibidores , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Neovascularização de Coroide/genética , Neovascularização de Coroide/patologia , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/antagonistas & inibidores , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Degeneração Macular/patologia , Proteínas Repressoras/antagonistas & inibidores , Proteínas Repressoras/genética , Transtornos da Visão/genética , Transtornos da Visão/patologia , Transtornos da Visão/terapia
20.
Br J Ophthalmol ; 104(1): 26-32, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-30910871

RESUMO

BACKGROUND: Episcleral brachytherapy is the most common eye-preserving treatment for medium-sized choroidal melanomas. γ-emitting iodine-125 (125I) and ß-emitting ruthenium-106 (106Ru) are widely used. The latter is however generally reserved for thinner tumours (<6 mm). In this study, we compare ocular and patient survival in thicker tumours treated with the respective radioisotope. METHODS: All patients with ≥5.5 mm thick choroidal melanomas who were treated with plaque brachytherapy at a single institution between 1 November 1979 and 31 December 2015 were included (n=571). Size-controlled Cox regression HRs for postbrachytherapy enucleation, repeated brachytherapy and melanoma-related mortality were calculated, as well as Kaplan-Meier disease-specific survival and relative 10-year survival in matched subgroups. RESULTS: 317 patients were treated with 106Ru and 254 with 125I. The rate of repeated brachytherapy was significantly higher among patients treated with 106Ru (8%) than with 125I (1%, p<0.001). Size-controlled Cox regression HRs for postbrachytherapy enucleation (125I vs 106Ru 0.7, p=0.083) and melanoma-related mortality were not significant (125I vs 106Ru 1.1, p=0.63). Similarly, Kaplan-Meier disease-specific and relative 10-year survival was comparable in matched groups of 5.5-7.4 mm (relative survival 106Ru 59%, 125I 56%) and ≥7.5 mm thick tumours (relative survival 106Ru 46%, 125I 44%). CONCLUSIONS: Rates of repeated brachytherapy were significantly higher among patients treated with 106Ru versus 125I for thick choroidal melanomas. There were, however, no significant differences in rates of enucleation or patient survival.


Assuntos
Braquiterapia/métodos , Neoplasias da Coroide/radioterapia , Radioisótopos do Iodo/uso terapêutico , Melanoma/radioterapia , Radioisótopos de Rutênio/uso terapêutico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Coroide/patologia , Neoplasias da Coroide/cirurgia , Enucleação Ocular/estatística & dados numéricos , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Melanoma/patologia , Melanoma/cirurgia , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Dosagem Radioterapêutica , Estudos Retrospectivos , Adulto Jovem
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