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Wilms tumor, the most common pediatric kidney cancer, resembles embryonic renal progenitors. Currently, there are no ways to therapeutically target Wilms tumor driver mutations, such as in the microRNA processing gene DROSHA. In this study, we used a "multiomics" approach to define the effects of DROSHA mutation in Wilms tumor. We categorized Wilms tumor mutations into four mutational subclasses with unique transcriptional effects: microRNA processing, MYCN activation, chromatin remodeling, and kidney developmental factors. In particular, we find that DROSHA mutations are correlated with de-repressing microRNA target genes that regulate differentiation and proliferation and a self-renewing, mesenchymal state. We model these findings by inhibiting DROSHA expression in a Wilms tumor cell line, which led to upregulation of the cell cycle regulator cyclin D2 (CCND2). Furthermore, we observed that DROSHA mutations in Wilms tumor and DROSHA silencing in vitro were associated with a mesenchymal state with aberrations in redox metabolism. Accordingly, we demonstrate that Wilms tumor cells lacking microRNAs are sensitized to ferroptotic cell death through inhibition of glutathione peroxidase 4, the enzyme that detoxifies lipid peroxides. Implications: This study reveals genotype-transcriptome relationships in Wilms tumor and points to ferroptosis as a potentially therapeutic vulnerability in one subset of Wilms tumor.
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Neoplasias Renais , Ribonuclease III , Tumor de Wilms , Humanos , Tumor de Wilms/genética , Tumor de Wilms/patologia , Tumor de Wilms/metabolismo , Ribonuclease III/genética , Ribonuclease III/metabolismo , Neoplasias Renais/genética , Neoplasias Renais/patologia , Neoplasias Renais/metabolismo , Regulação Neoplásica da Expressão Gênica , Mutação , MicroRNAs/genética , Linhagem Celular TumoralRESUMO
Patient-derived xenografts (PDX) remain valuable models for understanding the biology and for developing novel therapeutics. To expand current PDX models of childhood leukemia, we have developed new PDX models from Hispanic patients, a subgroup with a poorer overall outcome. Of 117 primary leukemia samples obtained, successful engraftment and serial passage in mice were achieved in 82 samples (70%). Hispanic patient samples engrafted at a rate (51/73, 70%) that was similar to non-Hispanic patient samples (31/45, 70%). With a new algorithm to remove mouse contamination in multi-omics datasets including methylation data, we found PDX models faithfully reflected somatic mutations, copy-number alterations, RNA expression, gene fusions, whole-genome methylation patterns, and immunophenotypes found in primary tumor (PT) samples in the first 50 reported here. This cohort of characterized PDX childhood leukemias represents a valuable resource in that germline DNA sequencing has allowed the unambiguous determination of somatic mutations in both PT and PDX.
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PURPOSE: Osteosarcoma research advancement requires enhanced data integration across different modalities and sources. Current osteosarcoma research, encompassing clinical, genomic, protein, and tissue imaging data, is hindered by the siloed landscape of data generation and storage. MATERIALS AND METHODS: Clinical, molecular profiling, and tissue imaging data for 573 patients with pediatric osteosarcoma were collected from four public and institutional sources. A common data model incorporating standardized terminology was created to facilitate the transformation, integration, and load of source data into a relational database. On the basis of this database, a data commons accompanied by a user-friendly web portal was developed, enabling various data exploration and analytics functions. RESULTS: The Osteosarcoma Explorer (OSE) was released to the public in 2021. Leveraging a comprehensive and harmonized data set on the backend, the OSE offers a wide range of functions, including Cohort Discovery, Patient Dashboard, Image Visualization, and Online Analysis. Since its initial release, the OSE has experienced an increasing utilization by the osteosarcoma research community and provided solid, continuous user support. To our knowledge, the OSE is the largest (N = 573) and most comprehensive research data commons for pediatric osteosarcoma, a rare disease. This project demonstrates an effective framework for data integration and data commons development that can be readily applied to other projects sharing similar goals. CONCLUSION: The OSE offers an online exploration and analysis platform for integrated clinical, molecular profiling, and tissue imaging data of osteosarcoma. Its underlying data model, database, and web framework support continuous expansion onto new data modalities and sources.
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Gerenciamento de Dados , Osteossarcoma , Criança , Humanos , Bases de Dados Factuais , Genômica , Osteossarcoma/diagnóstico por imagem , Osteossarcoma/genéticaRESUMO
Wilms tumor, the most common kidney cancer in pediatrics, arises from embryonic renal progenitors. Although many patients are cured with multimodal therapy, outcomes remain poor for those with high-risk features. Recent sequencing efforts have provided few biological or clinically actionable insights. Here, we performed DNA and RNA sequencing on 94 Wilms tumors to understand how Wilms tumor mutations transform the transcriptome to arrest differentiation and drive proliferation. We show that most Wilms tumor mutations fall into four classes, each with unique transcriptional signatures: microRNA processing, MYCN activation, chromatin remodeling, and kidney development. In particular, the microRNA processing enzyme DROSHA is one of the most commonly mutated genes in Wilms tumor. We show that DROSHA mutations impair pri-microRNA cleavage, de-repress microRNA target genes, halt differentiation, and overexpress cyclin D2 (CCND2). Several mutational classes converge to drive CCND2 overexpression, which could render them susceptible to cell-cycle inhibitors.
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Low-grade oncocytic tumor (LOT) of the kidney is a recently described entity with poorly understood pathogenesis. Using next-generation sequencing (NGS) and complementary approaches, we provide insight into its biology. We describe 22 LOT corresponding to 7 patients presenting with a median age of 75 years (range 63-86 years) and male to female ratio 2:5. All 22 tumors demonstrated prototypical microscopic features. Tumors were well-circumscribed and solid. They were composed of sheets of tumor cells in compact nests. Tumor cells had eosinophilic cytoplasm, round to oval nuclei (without nuclear membrane irregularities), focal subtle perinuclear halos, and occasional binucleation. Sharply delineated edematous stromal islands were often observed. Tumor cells were positive for PAX8, negative for CD117, and exhibited diffuse and strong cytokeratin-7 expression. Six patients presented with pT1 tumors. At a median follow-up of 29 months, four patients were alive without recurrence (three patients had died from unrelated causes). All tumors were originally classified as chromophobe renal cell carcinoma, eosinophilic variant (chRCC-eo). While none of the patients presented with known syndromic features, one patient with multiple bilateral LOTs was subsequently found to have a likely pathogenic germline TSC1 mutation. Somatic, likely activating, mutations in MTOR and RHEB were identified in all other evaluable LOTs. As assessed by phospho-S6 and phospho-4E-BP1, mTOR complex 1 (mTORC1) was activated across all cases but to different extent. MTOR mutant LOT exhibited lower levels of mTORC1 activation, possibly related to mTORC1 dimerization and the preservation of a wild-type MTOR copy (retained chromosome 1). Supporting its distinction from related entities, gene expression analyses showed that LOT clustered separately from classic chRCC, chRCC-eo, and RO. In summary, converging mTORC1 pathway mutations, mTORC1 complex activation, and a distinctive gene expression signature along with characteristic phenotypic features support LOT designation as a distinct entity with both syndromic and non-syndromic cases associated with an indolent course.
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Adenoma Oxífilo , Carcinoma de Células Renais , Neoplasias Renais , Adenoma Oxífilo/genética , Adenoma Oxífilo/patologia , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/genética , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/patologia , Feminino , Células Germinativas/química , Células Germinativas/patologia , Humanos , Rim/patologia , Neoplasias Renais/genética , Neoplasias Renais/patologia , Masculino , Pessoa de Meia-Idade , Mutação , Serina-Treonina Quinases TOR/genéticaRESUMO
Metastasis is the principal cause of cancer related deaths. Tumor invasion is essential for metastatic spread. However, determinants of invasion are poorly understood. We addressed this knowledge gap by leveraging a unique attribute of kidney cancer. Renal tumors invade into large vessels forming tumor thrombi (TT) that migrate extending sometimes into the heart. Over a decade, we prospectively enrolled 83 ethnically-diverse patients undergoing surgical resection for grossly invasive tumors at UT Southwestern Kidney Cancer Program. In this study, we perform comprehensive histological analyses, integrate multi-region genomic studies, generate in vivo models, and execute functional studies to define tumor invasion and metastatic competence. We find that invasion is not always associated with the most aggressive clone. Driven by immediate early genes, invasion appears to be an opportunistic trait attained by subclones with diverse oncogenomic status in geospatial proximity to vasculature. We show that not all invasive tumors metastasize and identify determinants of metastatic competency. TT associated with metastases are characterized by higher grade, mTOR activation and a particular immune contexture. Moreover, TT grade is a better predictor of metastasis than overall tumor grade, which may have implications for clinical practice.
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Carcinoma de Células Renais/secundário , Regulação Neoplásica da Expressão Gênica , Neoplasias Renais/patologia , Trombose/genética , Idoso , Animais , Carcinoma de Células Renais/complicações , Carcinoma de Células Renais/diagnóstico , Carcinoma de Células Renais/genética , Linhagem Celular Tumoral , Variações do Número de Cópias de DNA , Feminino , Humanos , Rim/irrigação sanguínea , Rim/patologia , Neoplasias Renais/complicações , Neoplasias Renais/diagnóstico , Neoplasias Renais/genética , Masculino , Camundongos , Pessoa de Meia-Idade , Gradação de Tumores , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Estudos Prospectivos , RNA-Seq , Fatores de Risco , Trombose/patologia , Sequenciamento do Exoma , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Germ cell tumors (GCTs) are considered a rare disease but are the most common solid tumors in adolescents and young adults, accounting for 15% of all malignancies in this age group. The rarity of GCTs in some groups, particularly children, has impeded progress in treatment and biologic understanding. The most effective GCT research will result from the interrogation of data sets from historical and prospective trials across institutions. However, inconsistent use of terminology among groups, different sample-labeling rules, and lack of data standards have hampered researchers' efforts in data sharing and across-study validation. To overcome the low interoperability of data and facilitate future clinical trials, we worked with the Malignant Germ Cell International Consortium (MaGIC) and developed a GCT clinical data model as a uniform standard to curate and harmonize GCT data sets. This data model will also be the standard for prospective data collection in future trials. Using the GCT data model, we developed a GCT data commons with data sets from both MaGIC and public domains as an integrated research platform. The commons supports functions, such as data query, management, sharing, visualization, and analysis of the harmonized data, as well as patient cohort discovery. This GCT data commons will facilitate future collaborative research to advance the biologic understanding and treatment of GCTs. Moreover, the framework of the GCT data model and data commons will provide insights for other rare disease research communities into developing similar collaborative research platforms.
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Neoplasias Embrionárias de Células Germinativas , Neoplasias , Adolescente , Estudos de Coortes , Humanos , Disseminação de Informação , Neoplasias Embrionárias de Células Germinativas/epidemiologia , Neoplasias Embrionárias de Células Germinativas/terapiaRESUMO
Lack of responsiveness to checkpoint inhibitors is a central problem in the modern era of cancer immunotherapy. Tumor neoantigens are critical targets of the host antitumor immune response, and their presence correlates with the efficacy of immunotherapy treatment. Many studies involving assessment of tumor neoantigens principally focus on total neoantigen load, which simplistically treats all neoantigens equally. Neoantigen load has been linked with treatment response and prognosis in some studies but not others. We developed a Cauchy-Schwarz index of Neoantigens (CSiN) score to better account for the degree of concentration of immunogenic neoantigens in truncal mutations. Unlike total neoantigen load determinations, CSiN incorporates the effect of both clonality and MHC binding affinity of neoantigens when characterizing tumor neoantigen profiles. By analyzing the clinical responses in 501 treated patients with cancer (with most receiving checkpoint inhibitors) and the overall survival of 1978 patients with cancer at baseline, we showed that CSiN scores predict treatment response to checkpoint inhibitors and prognosis in patients with melanoma, lung cancer, and kidney cancer. CSiN score substantially outperformed prior genetics-based prediction methods of responsiveness and fills an important gap in research involving assessment of tumor neoantigen burden.
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Antígenos de Neoplasias/imunologia , Células Clonais/imunologia , Células Clonais/patologia , Imunoterapia , Neoplasias/patologia , Neoplasias/terapia , Idoso , Antígenos de Neoplasias/genética , Estudos de Coortes , Feminino , Perfilação da Expressão Gênica , Humanos , Neoplasias Renais/genética , Neoplasias Renais/imunologia , Neoplasias Renais/patologia , Neoplasias Renais/terapia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/terapia , Masculino , Melanoma/diagnóstico , Melanoma/genética , Melanoma/imunologia , Melanoma/patologia , Mutação , Neoplasias/imunologia , Resultado do TratamentoRESUMO
BACKGROUND: Clear cell renal cell carcinoma (ccRCC) is a particularly challenging tumor type because of its extensive phenotypic variability as well as intra-tumoral heterogeneity (ITH). Clinically, this complexity has been reduced to a handful of pathological variables such as stage, grade and necrosis, but these variables fail to capture the breadth of the disease. How different phenotypes affect patient prognosis and influence therapeutic response is poorly understood. Extensive ITH illustrates remarkable plasticity, providing a framework to study tumor evolution. While multiregional genomic analyses have shown evolution from an ancient clone that acquires metastatic competency over time, these studies have been conducted agnostic to morphological cues and phenotypic plasticity. METHODS: We established a systematic ontology of ccRCC phenotypic variability by developing a multi-scale framework along three fundamental axes: tumor architecture, cytology and the microenvironment. We defined 33 parameters, which we comprehensively evaluated in 549 consecutive ccRCCs retrospectively. We systematically evaluated the impact of each parameter on patient outcomes, and assessed their contribution through multivariate analyses. We measured therapeutic impact in the context of anti-angiogenic therapies. We applied dimensionality reduction by t-distributed stochastic neighbor embedding (t-SNE) algorithms to tumor architectures for the study of tumor evolution superimposing tumor size and grade vectors. Evolutionary models were refined through empirical analyses of directed evolution of tumor intravascular extensions, and metastatic competency (as determined by tumor reconstitution in a heterologous host). FINDINGS: We discovered several novel ccRCC phenotypes, developed an integrated taxonomy, and identified features that improve current prognostic models. We identified a subset of ccRCCs refractory to anti-angiogenic therapies. We developed a model of tumor evolution, which revealed converging evolutionary trajectories into an aggressive type. INTERPRETATION: This work serves as a paradigm for deconvoluting tumor complexity and illustrates how morphological analyses can improve our understanding of ccRCC pleiotropy. We identified several subtypes associated with aggressive biology, and differential response to targeted therapies. By analyzing patterns of spatial and temporal co-occurrence, intravascular tumor extensions and metastatic competency, we were able to identify distinct trajectories of convergent phenotypic evolution.
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Carcinoma de Células Renais/classificação , Carcinoma de Células Renais/patologia , Neoplasias Renais/classificação , Neoplasias Renais/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Inibidores da Angiogênese/farmacologia , Inibidores da Angiogênese/uso terapêutico , Animais , Carcinoma de Células Renais/irrigação sanguínea , Carcinoma de Células Renais/tratamento farmacológico , Intervalo Livre de Doença , Feminino , Heterogeneidade Genética , Humanos , Neoplasias Renais/irrigação sanguínea , Neoplasias Renais/tratamento farmacológico , Masculino , Camundongos Endogâmicos NOD , Camundongos SCID , Análise Multivariada , Invasividade Neoplásica , Estadiamento de Neoplasias , Neovascularização Patológica/patologia , Fenótipo , Prognóstico , Fatores de Risco , Processos Estocásticos , Microambiente Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , Adulto JovemRESUMO
We recently developed a novel computational algorithm that incorporates Bayesian methodology to identify rhabdomyosarcoma disease genes whose expression level correlates with copy-number variations, and we identified PLAG1 as a candidate oncogenic driver. Although PLAG1 has been shown to contribute to other type of cancers, its role in rhabdomyosarcoma has not been elucidated. We observed that PLAG1 mRNA is highly expressed in rhabdomyosarcoma and is associated with PLAG1 gene copy-number gain. Knockdown of PLAG1 dramatically decreased cell accumulation and induced apoptosis in rhabdomyosarcoma cells, whereas its ectopic expression increased cell accumulation in vitro and as a xenograft and promoted G1 to S-phase cell-cycle progression. We found that PLAG1 regulates IGF2 expression and influences AKT and MAPK pathways in rhabdomyosarcoma, and IGF2 partially rescues cell death triggered by PLAG1 knockdown. The expression level of PLAG1 correlated with the IC50 of rhabdomyosarcoma cells to BMS754807, an IGF receptor inhibitor. IMPLICATIONS: Our data demonstrate that PLAG1 contributes to proliferation and survival of rhabdomyosarcoma cells at least partially by inducing IGF2, and this new understanding may have the potential for clinical translation.
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Proteínas de Ligação a DNA/metabolismo , Rabdomiossarcoma/genética , Animais , Apoptose/fisiologia , Teorema de Bayes , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Proteínas de Ligação a DNA/biossíntese , Proteínas de Ligação a DNA/genética , Dosagem de Genes , Xenoenxertos , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Rabdomiossarcoma/metabolismo , Rabdomiossarcoma/patologia , Análise de SobrevidaRESUMO
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
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Disruption of the CDKN2A (INK4A/ARF) and B (INK4B) genes, which encode three function-independent tumor suppressors, is one of the most common events in human cancer. Because their relative importance in tumor prevention appears to be species- and context-specific, studying their regulation can shed light on mechanisms by which they are bypassed in malignant transformation. We previously unveiled a new pathway in which TGFß selectively induces Arf at mouse Cdkn2a in eye development and cultured fibroblasts. As TGFß signaling is often derailed in cancer development or progression, we investigated its control of CDKN2A/B in human cancer. Computational analyses of sequencing and array data from nearly 11,000 patients with cancer in TCGA showed discordant expression of ARF and INK4A in most cancer subtypes, with gene copy-number loss and promoter methylation involved in only a subset. Using HeLa cells as a model, we found that exogenous TGFß induced ARF mRNA and protein, and ARF knockdown limited TGFß-mediated growth suppression. TGFß-mediated ARF mRNA induction required SMAD2/3, p38MAPK, and SP1, and ARF mRNA was induced without added RNAPII recruitment. Chromatin immunoprecipitation unveiled a remote enhancer element engaged by TGFß by a mechanism that partially depended on p38MAPK. CRISPR-based editing of this enhancer limited induction of ARF and INK4B by TGFß, but not by oncogenic RAS. IMPLICATIONS: Our findings reveal new molecular mechanisms by which CDKN2A/B regulation is coupled to external cues, and those findings represent entry points to further explore pharmacologic strategies to restore their expression in cancer.
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Inibidor de Quinase Dependente de Ciclina p15/genética , Inibidor p16 de Quinase Dependente de Ciclina/genética , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Elementos Facilitadores Genéticos , Neoplasias/genética , Fator de Crescimento Transformador beta/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p15/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Células HeLa , Humanos , Modelos Biológicos , Neoplasias/metabolismo , Transdução de Sinais/efeitos dos fármacos , Regulação para CimaRESUMO
We constructed a lung cancer-specific database housing expression data and clinical data from over 6700 patients in 56 studies. Expression data from 23 genome-wide platforms were carefully processed and quality controlled, whereas clinical data were standardized and rigorously curated. Empowered by this lung cancer database, we created an open access web resource-the Lung Cancer Explorer (LCE), which enables researchers and clinicians to explore these data and perform analyses. Users can perform meta-analyses on LCE to gain a quick overview of the results on tumor vs non-malignant tissue (normal) differential gene expression and expression-survival association. Individual dataset-based survival analysis, comparative analysis, and correlation analysis are also provided with flexible options to allow for customized analyses from the user.
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Expressão Gênica/genética , Neoplasias Pulmonares/genética , Perfilação da Expressão Gênica/métodos , Estudo de Associação Genômica Ampla/métodos , Genômica/métodos , Humanos , Análise de SobrevidaRESUMO
The in vivo function of microRNAs (miRs) in diabetic retinopathy (DR) and age-related macular degeneration (AMD) remains unclear. We report here that let-7 family members are expressed in retinal and choroidal endothelial cells (ECs). In ECs, overexpression of let-7 by adenovirus represses EC proliferation, migration, and networking in vitro, whereas inhibition of the let-7 family with a locked nucleic acid (LNA)-anti-miR has the opposite effect. Mechanistically, silencing of the let-7 target HMGA2 gene mimics the phenotype of let-7 overexpression in ECs. let-7 transgenic (let-7-Tg) mice show features of nonproliferative DR, including tortuous retinal vessels and defective pericyte coverage. However, these mice develop significantly less choroidal neovascularization (CNV) compared to wild-type controls after laser injury. Consistently, silencing of let-7 in the eye increased laser-induced CNV in wild-type mice. Together, our data establish a causative role of let-7 in nonproliferative diabetic retinopathy and a repressive function of let-7 in pathological angiogenesis, suggesting distinct implications of let-7 in the pathogenesis of DR and AMD.
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microRNAs or miRs have been shown to be pivotal modulators of vascular development. The strand and cell type-specific function of miR-126 in angiogenesis, especially pathological angiogenesis, remains poorly defined. We characterized the retinal vascular phenotype of miR-126-/- mice, and tested the function of miR-126 strands (miR-126-3p and -5p) using in vitro angiogenesis models and a mouse model of neovascular age-related macular degeneration. We found that miR-126 is critical for retinal vascular development but has dual function in pathological angiogenesis. miR-126-/- mice showed defective postnatal retinal vascular development and remodeling, which is partially rescued by genetic knockout of its target gene Spred-1. Surprisingly, either silencing miR-126-3p by LNA-antimiR or overexpressing miR-126-3p by miRNA mimic repressed laser-induced choroidal neovascularization. To dissect the underlying mechanism, we found in endothelial cells, silencing of miR-126-3p repressed angiogenesis, while overexpression of miR-126-5p enhanced angiogenesis. However, in retinal pigment epithelial cells, miR-126-3p repressed vascular endothelial growth factor (VEGF-A) expression via a novel mechanism of regulating αB-Crystallin promoter activity and by directly targeting VEGF-A 3'-untranslated region. These findings provide first genetic evidence that miR-126 is required for the development of different retinal vascular layers, and also uncover a strand and cell type-specific function of miR-126 in ocular pathological angiogenesis.
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Fibroblastos/citologia , Peptídeos e Proteínas de Sinalização Intracelular/genética , Degeneração Macular/genética , Proteínas de Membrana/genética , MicroRNAs/genética , Neovascularização Patológica/genética , Neovascularização Fisiológica , Proteínas Adaptadoras de Transdução de Sinal , Animais , Proliferação de Células , Técnicas de Cocultura , Modelos Animais de Doenças , Olho/metabolismo , Fibroblastos/metabolismo , Regulação da Expressão Gênica , Técnicas de Inativação de Genes , Células Endoteliais da Veia Umbilical Humana , Humanos , Camundongos , Especificidade de Órgãos , Fator A de Crescimento do Endotélio Vascular/genéticaRESUMO
The late stage of dry age-related macular degeneration (AMD), or geographic atrophy (GA), is characterized by extensive retinal pigment epithelial (RPE) cell death, and a cure is not available currently. We have recently demonstrated that RPE cells die from necrosis in response to oxidative stress, providing a potential novel mechanism for RPE death in AMD. In this study, we screened U.S. Food and Drug Administration-approved natural compounds and identified gossypol acetic acid (GAA) as a potent inhibitor of oxidative stress-induced RPE cell death. GAA induces antioxidative response and inhibits accumulation of excessive reactive oxygen species in cells, through which it prevents the activation of intrinsic necrotic pathway in response to oxidative stress. Sestrin2 (SESN2) is found to mediate GAA function in antioxidative response and RPE survival upon oxidative stress. Moreover, Forkhead box O3 transcription factor (FoxO3) is further found to be required for GAA-mediated SESN2 expression and RPE survival. Mechanistically, GAA promotes FoxO3 nuclear translocation and binding to the SESN2 enhancer, which in turn increases its transcriptional activity. Taken together, we have identified GAA as a potent inhibitor of oxidative stress-induced RPE necrosis by regulating the FoxO3/SESN2 pathway. This study may have significant implications in the therapeutics of age-related diseases, especially GA.
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Fatores de Transcrição Forkhead/genética , Gossipol/análogos & derivados , Necrose/tratamento farmacológico , Proteínas Nucleares/genética , Estresse Oxidativo/efeitos dos fármacos , Epitélio Pigmentado da Retina/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Antioxidantes/farmacologia , Morte Celular/efeitos dos fármacos , Morte Celular/genética , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Proteína Forkhead Box O3 , Gossipol/farmacologia , Humanos , Degeneração Macular/tratamento farmacológico , Degeneração Macular/genética , Degeneração Macular/metabolismo , Necrose/genética , Necrose/metabolismo , Estresse Oxidativo/genética , Espécies Reativas de Oxigênio/metabolismo , Epitélio Pigmentado da Retina/metabolismo , Pigmentos da Retina/genética , Pigmentos da Retina/metabolismo , Transdução de Sinais/genética , Estados Unidos , United States Food and Drug AdministrationRESUMO
Actin cytoskeleton is critical for cell motility and division, both of which are important for angiogenesis. MicroRNAs (miRNA/miR) are emerging as pivotal modulators of vascular development and disease. How miRNAs regulate actin cytoskeleton dynamics in endothelial cells (EC) and neovascularization is still unclear. Here, we report that miR-24 regulates actin dynamics in ECs through targeting multiple members downstream of Rho signaling, including Pak4, Limk2, and Diaph1 proteins. Overexpression of miR-24 in ECs blocks stress fiber and lamellipodia formation, represses EC migration, proliferation, and tube formation in vitro, as well as angiogenesis in an ex vivo aortic ring assay. Moreover, subretinal delivery of miR-24 mimics represses laser-induced choroidal neovascularization (CNV) in vivo. Mechanistically, knockdown of miR-24 target protein LIMK2 or PAK4 inhibits stress fiber formation and tube formation in vitro, mimicking miR-24 overexpression phenotype in angiogenesis, while overexpression of LIMK2 and PAK4 by adenoviruses partially rescued the tube formation defects in miR-24 overexpressing ECs. Taken together, these findings suggest that miR-24 represses angiogenesis by simultaneously regulating multiple components in the actin cytoskeleton pathways. Manipulation of actin cytoskeleton pathways by miR-24 may represent an attractive therapeutic solution for the treatment of wet age-related macular degeneration (AMD) and other vascular diseases.
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Citoesqueleto de Actina/genética , Citoesqueleto de Actina/metabolismo , Neovascularização de Coroide/genética , Neovascularização de Coroide/metabolismo , MicroRNAs/genética , Transdução de Sinais , Regiões 3' não Traduzidas , Animais , Sequência de Bases , Linhagem Celular , Neovascularização de Coroide/patologia , Células Endoteliais/metabolismo , Regulação da Expressão Gênica , Inativação Gênica , Humanos , Quinases Lim/genética , Masculino , Camundongos , MicroRNAs/química , MicroRNAs/metabolismo , Modelos Biológicos , Fenótipo , Interferência de RNA , Quinases Ativadas por p21/genéticaRESUMO
Neovascularization (NV) in the cornea is a major cause of vision impairment and corneal blindness. Hemangiogenesis and lymphangiogenesis induced by inflammation underlie the pathogenesis of corneal NV. The current mainstay treatment, corticosteroid, treats the inflammation associated with corneal NV, but is not satisfactory due to such side effects as cataract and the increase in intraocular pressure. It is imperative to develop a novel therapy that specifically targets the hemangiogenesis, lymphangiogenesis, and inflammation pathways underlying corneal NV. Histone deacetylase inhibitors (HDACi) have been in clinical trials for cancer and other diseases. In particular, HDACi suberoylanilide hydroxamic acid (SAHA, vorinostat, Zolinza) has been approved by the FDA for the treatment of cutaneous T-cell lymphoma. The functional mechanism of SAHA in cancer and especially in corneal NV remains unclear. Here, we show that topical application of SAHA inhibits neovascularization in an alkali-burn corneal injury model. Mechanistically, SAHA inhibits corneal NV by repressing hemangiogenesis, inflammation pathways, and previously overlooked lymphangiogenesis. Topical SAHA is well tolerated on the ocular surface. In addition, the potency of SAHA in corneal NV appears to be comparable to the current steroid therapy. SAHA may possess promising therapeutic potential in alkali-burn corneal injury and other inflammatory neovascularization disorders.
Assuntos
Queimaduras Químicas/tratamento farmacológico , Doenças da Córnea/tratamento farmacológico , Lesões da Córnea , Queimaduras Oculares/tratamento farmacológico , Inibidores de Histona Desacetilases/farmacologia , Ácidos Hidroxâmicos/farmacologia , Álcalis , Animais , Queimaduras Químicas/patologia , Córnea/irrigação sanguínea , Córnea/efeitos dos fármacos , Córnea/enzimologia , Doenças da Córnea/patologia , Neovascularização da Córnea/induzido quimicamente , Neovascularização da Córnea/tratamento farmacológico , Neovascularização da Córnea/patologia , Modelos Animais de Doenças , Queimaduras Oculares/induzido quimicamente , Queimaduras Oculares/enzimologia , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/genética , Inflamação/tratamento farmacológico , Inflamação/patologia , Linfangiogênese/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/patologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , VorinostatRESUMO
Primitive erythropoiesis defines the onset of hematopoiesis in the yolk sac of the early embryo and is initiated by the emergence of progenitors assayed as colony-forming cells (EryP-CFCs). EryP-CFCs are detected for only a narrow window during embryonic development, suggesting that both their initiation and termination are tightly controlled. Using the embryonic stem differentiation system to model primitive erythropoiesis, we found that miR-126 regulates the termination of EryP-CFC development. Analyses of miR-126 null embryos revealed that this miR also regulates EryP-CFCs in vivo. We identified vascular cell adhesion molecule-1 (Vcam-1) expressed by a mesenchymal cell population as a relevant target of miR-126. Interaction of EryP-CFCs with Vcam-1 accelerated their maturation to ßh1-globin(+) and Ter119(+) cells through a Src family kinase. These findings uncover a cell nonautonomous regulatory pathway for primitive erythropoiesis that may provide insight into the mechanism(s) controlling the developmental switch from primitive to definitive hematopoiesis.