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1.
Cell Rep ; 42(12): 113286, 2023 12 26.
Artigo em Inglês | MEDLINE | ID: mdl-37995179

RESUMO

Lung adenocarcinoma (LUAD) is the most prevalent subtype of lung cancer and presents clinically with a high degree of biological heterogeneity and distinct clinical outcomes. The current paradigm of LUAD etiology posits alveolar epithelial type II (AT2) cells as the primary cell of origin, while the role of AT1 cells in LUAD oncogenesis remains unknown. Here, we examine oncogenic transformation in mouse Gram-domain containing 2 (Gramd2)+ AT1 cells via oncogenic KRASG12D. Activation of KRASG12D in AT1 cells induces multifocal LUAD, primarily of papillary histology. Furthermore, KRT8+ intermediate cell states were observed in both AT2- and AT1-derived LUAD, but SCGB3A2+, another intermediate cell marker, was primarily associated with AT1 cells, suggesting different mechanisms of tumor evolution. Collectively, our study reveals that Gramd2+ AT1 cells can serve as a cell of origin for LUAD and suggests that distinct subtypes of LUAD based on cell of origin be considered in the development of therapeutics.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Animais , Camundongos , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/patologia , Transformação Celular Neoplásica/metabolismo , Neoplasias Pulmonares/patologia , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo
2.
Wiley Interdiscip Rev Dev Biol ; 10(6): e399, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33145915

RESUMO

The pulmonary system is comprised of two main compartments, airways and alveolar space. Their tissue and cellular complexity ensure lung function and protection from external agents, for example, virus. Two-dimensional (2D) in vitro systems and animal models have been largely employed to elucidate the molecular mechanisms underlying human lung development, physiology, and pathogenesis. However, neither of these models accurately recapitulate the human lung environment and cellular crosstalk. More recently, human-derived three-dimensional (3D) models have been generated allowing for a deeper understanding of cell-to-cell communication. However, the availability and accessibility of primary human cell sources from which generate the 2D and 3D models may be limited. In the past few years, protocols have been developed to successfully employ human pluripotent stem cells (hPSCs) and differentiate them toward pulmonary fate in vitro. In the present review, we discuss the advantages and pitfalls of hPSC-derived lung 2D and 3D models, including the main characteristics and potentials for these models and their current and future applications for modeling development and diseases. Lung organoids currently represent the closest model to the human pulmonary system. We further focus on the applications of lung organoids for the study of human diseases such as pulmonary fibrosis, infectious diseases, and lung cancer. Finally, we discuss the present limitations and potential future applications of 3D lung organoids. This article is categorized under: Adult Stem Cells, Tissue Renewal, and Regeneration > Stem Cells and Disease Adult Stem Cells, Tissue Renewal, and Regeneration > Stem Cell Differentiation and Reversion.


Assuntos
Organoides , Células-Tronco Pluripotentes , Animais , Diferenciação Celular , Humanos , Pulmão , Organogênese
3.
Int J Mol Sci ; 21(12)2020 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-32575472

RESUMO

Reactive oxygen species (ROS) affect many cellular functions and the proper redox balance between ROS and antioxidants contributes substantially to the physiological welfare of the cell. During pathological conditions, an altered redox equilibrium leads to increased production of ROS that in turn may cause oxidative damage. MicroRNAs (miRNAs) regulate gene expression at the post-transcriptional level contributing to all major cellular processes, including oxidative stress and cell death. Several miRNAs are expressed in response to ROS to mediate oxidative stress. Conversely, oxidative stress may lead to the upregulation of miRNAs that control mechanisms to buffer the damage induced by ROS. This review focuses on the complex crosstalk between miRNAs and ROS in diseases of the cardiac (i.e., cardiac hypertrophy, heart failure, myocardial infarction, ischemia/reperfusion injury, diabetic cardiomyopathy) and pulmonary (i.e., idiopathic pulmonary fibrosis, acute lung injury/acute respiratory distress syndrome, asthma, chronic obstructive pulmonary disease, lung cancer) compartments. Of note, miR-34a, miR-144, miR-421, miR-129, miR-181c, miR-16, miR-31, miR-155, miR-21, and miR-1/206 were found to play a role during oxidative stress in both heart and lung pathologies. This review comprehensively summarizes current knowledge in the field.


Assuntos
Cardiopatias/genética , Pneumopatias/genética , MicroRNAs/genética , Espécies Reativas de Oxigênio/metabolismo , Regulação da Expressão Gênica , Cardiopatias/metabolismo , Humanos , Pneumopatias/metabolismo , Estresse Oxidativo
4.
Am J Physiol Lung Cell Mol Physiol ; 319(1): L173-L184, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32432919

RESUMO

The alveolar epithelium is comprised of two cell types, alveolar epithelial type 1 (AT1) and type 2 (AT2) cells, the latter being capable of self-renewal and transdifferentiation into AT1 cells for normal maintenance and restoration of epithelial integrity following injury. MicroRNAs (miRNAs) are critical regulators of several biological processes, including cell differentiation; however, their role in establishment/maintenance of cellular identity in adult alveolar epithelium is not well understood. To investigate this question, we performed genome-wide analysis of sequential changes in miRNA and gene expression profiles using a well-established model in which human AT2 (hAT2) cells transdifferentiate into AT1-like cells over time in culture that recapitulates many aspects of transdifferentiation in vivo. We defined three phases of miRNA expression during the transdifferentiation process as "early," "late," and "consistently" changed, which were further subclassified as up- or downregulated. miRNAs with altered expression at all time points during transdifferentiation were the largest subgroup, suggesting the need for consistent regulation of signaling pathways to mediate this process. Target prediction analysis and integration with previously published gene expression data identified glucocorticoid signaling as the top pathway regulated by miRNAs. Serum/glucocorticoid-regulated kinase 1 (SGK1) emerged as a central regulatory factor, whose downregulation correlated temporally with gain of hsa-miR-424 and hsa-miR-503 expression. Functional validation demonstrated specific targeting of these miRNAs to the 3'-untranslated region of SGK1. These data demonstrate the time-related contribution of miRNAs to the alveolar transdifferentiation process and suggest that inhibition of glucocorticoid signaling is necessary to achieve the AT1-like cell phenotype.


Assuntos
Diferenciação Celular , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Genoma Humano , MicroRNAs/metabolismo , Alvéolos Pulmonares/metabolismo , Transcriptoma/genética , Sequência de Bases , Diferenciação Celular/genética , Linhagem Celular , Transdiferenciação Celular/genética , Regulação da Expressão Gênica , Glucocorticoides/metabolismo , Humanos , Proteínas Imediatamente Precoces/metabolismo , MicroRNAs/genética , Proteínas Serina-Treonina Quinases/metabolismo
5.
Int J Cancer ; 143(12): 3169-3180, 2018 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-30325015

RESUMO

Claudins are a family of transmembrane proteins integral to the structure and function of tight junctions (TJ). Disruption of TJ and alterations in claudin expression are important features of invasive and metastatic cancer cells. Expression of CLDN18.1, the lung-specific isoform of CLDN18, is markedly decreased in lung adenocarcinoma (LuAd). Furthermore, we recently observed that aged Cldn18 -/- mice have increased propensity to develop LuAd. We now demonstrate that CLDN18.1 expression correlates inversely with promoter methylation and with LuAd patient mortality. In addition, when restored in LuAd cells that have lost expression, CLDN18.1 markedly attenuates malignant properties including xenograft tumor growth in vivo as well as cell proliferation, migration, invasion and anchorage-independent colony formation in vitro. Based on high throughput analyses of Cldn18 -/- murine lung alveolar epithelial type II cells, as well as CLDN18.1-repleted human LuAd cells, we hypothesized and subsequently confirmed by Western analysis that CLDN18.1 inhibits insulin-like growth factor-1 receptor (IGF-1R) and AKT phosphorylation. Consistent with recent data in Cldn18 -/- knockout mice, expression of CLDN18.1 in human LuAd cells also decreased expression of transcriptional co-activator with PDZ-binding motif (TAZ) and Yes-associated protein (YAP) and their target genes, contributing to its tumor suppressor activity. Moreover, analysis of LuAd cells in which YAP and/or TAZ are silenced with siRNA suggests that inhibition of TAZ, and possibly YAP, is also involved in CLDN18.1-mediated AKT inactivation. Taken together, these data indicate a tumor suppressor role for CLDN18.1 in LuAd mediated by a regulatory network that encompasses YAP/TAZ, IGF-1R and AKT signaling.


Assuntos
Adenocarcinoma de Pulmão/metabolismo , Claudinas/fisiologia , Neoplasias Pulmonares/metabolismo , Transdução de Sinais/fisiologia , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/patologia , Animais , Western Blotting , Proliferação de Células , Claudinas/genética , Metilação de DNA , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Camundongos , Camundongos Knockout , Invasividade Neoplásica , Metástase Neoplásica , Fosforilação , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-yes/metabolismo , Receptor IGF Tipo 1/metabolismo , Transativadores , Fatores de Transcrição , Proteínas com Motivo de Ligação a PDZ com Coativador Transcricional
6.
J Physiol ; 595(19): 6249-6262, 2017 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-28737214

RESUMO

KEY POINTS: While autologous stem cell-based therapies are currently being tested on elderly patients, there are limited data on the function of aged stem cells and in particular c-kit+ cardiac progenitor cells (CPCs). We isolated c-kit+ cells from young (3 months) and aged (24 months) C57BL/6 mice to compare their biological properties. Aged CPCs have increased senescence, decreased stemness and reduced capacity to proliferate or to differentiate following dexamethasone (Dex) treatment in vitro, as evidenced by lack of cardiac lineage gene upregulation. Aged CPCs fail to activate mitochondrial biogenesis and increase proteins involved in mitochondrial oxidative phosphorylation in response to Dex. Aged CPCs fail to upregulate paracrine factors that are potentially important for proliferation, survival and angiogenesis in response to Dex. The results highlight marked differences between young and aged CPCs, which may impact future design of autologous stem cell-based therapies. ABSTRACT: Therapeutic use of c-kit+ cardiac progenitor cells (CPCs) is being evaluated for regenerative therapy in older patients with ischaemic heart failure. Our understanding of the biology of these CPCs has, however, largely come from studies of young cells and animal models. In the present study we examined characteristics of CPCs isolated from young (3 months) and aged (24 months) mice that could underlie the diverse outcomes reported for CPC-based therapeutics. We observed morphological differences and altered senescence indicated by increased senescence-associated markers ß-galactosidase and p16 mRNA in aged CPCs. The aged CPCs also proliferated more slowly than their young counterparts and expressed lower levels of the stemness marker LIN28. We subsequently treated the cells with dexamethasone (Dex), routinely used to induce commitment in CPCs, for 7 days and analysed expression of cardiac lineage marker genes. While MEF2C, GATA4, GATA6 and PECAM mRNAs were significantly upregulated in response to Dex treatment in young CPCs, their expression was not increased in aged CPCs. Interestingly, Dex treatment of aged CPCs also failed to increase mitochondrial biogenesis and expression of the mitochondrial proteins Complex III and IV, consistent with a defect in mitochondria complex assembly in the aged CPCs. Dex-treated aged CPCs also had impaired ability to upregulate expression of paracrine factor genes and the conditioned media from these cells had reduced ability to induce angiogenesis in vitro. These findings could impact the design of future CPC-based therapeutic approaches for the treatment of older patients suffering from cardiac injury.


Assuntos
Células-Tronco Adultas/metabolismo , Envelhecimento/metabolismo , Senescência Celular , Miócitos Cardíacos/metabolismo , Células-Tronco Adultas/citologia , Células-Tronco Adultas/efeitos dos fármacos , Animais , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Dexametasona/farmacologia , Complexo de Proteínas da Cadeia de Transporte de Elétrons/genética , Complexo de Proteínas da Cadeia de Transporte de Elétrons/metabolismo , Fatores de Transcrição GATA/genética , Fatores de Transcrição GATA/metabolismo , Fatores de Transcrição MEF2/genética , Fatores de Transcrição MEF2/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Miócitos Cardíacos/citologia , Miócitos Cardíacos/efeitos dos fármacos , Biogênese de Organelas , Molécula-1 de Adesão Celular Endotelial a Plaquetas/genética , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Proteínas Proto-Oncogênicas c-kit/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo
7.
Circ Res ; 115(2): 273-83, 2014 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-24807785

RESUMO

RATIONALE: The sympathetic nervous system plays a fundamental role in the regulation of myocardial function. During chronic pressure overload, overactivation of the sympathetic nervous system induces the release of catecholamines, which activate ß-adrenergic receptors in cardiomyocytes and lead to increased heart rate and cardiac contractility. However, chronic stimulation of ß-adrenergic receptors leads to impaired cardiac function, and ß-blockers are widely used as therapeutic agents for the treatment of cardiac disease. MicroRNA-133 (miR-133) is highly expressed in the myocardium and is involved in controlling cardiac function through regulation of messenger RNA translation/stability. OBJECTIVE: To determine whether miR-133 affects ß-adrenergic receptor signaling during progression to heart failure. METHODS AND RESULTS: Based on bioinformatic analysis, ß1-adrenergic receptor (ß1AR) and other components of the ß1AR signal transduction cascade, including adenylate cyclase VI and the catalytic subunit of the cAMP-dependent protein kinase A, were predicted as direct targets of miR-133 and subsequently validated by experimental studies. Consistently, cAMP accumulation and activation of downstream targets were repressed by miR-133 overexpression in both neonatal and adult cardiomyocytes following selective ß1AR stimulation. Furthermore, gain-of-function and loss-of-function studies of miR-133 revealed its role in counteracting the deleterious apoptotic effects caused by chronic ß1AR stimulation. This was confirmed in vivo using a novel cardiac-specific TetON-miR-133 inducible transgenic mouse model. When subjected to transaortic constriction, TetON-miR-133 inducible transgenic mice maintained cardiac performance and showed attenuated apoptosis and reduced fibrosis compared with control mice. CONCLUSIONS: miR-133 controls multiple components of the ß1AR transduction cascade and is cardioprotective during heart failure.


Assuntos
AMP Cíclico/fisiologia , MicroRNAs/fisiologia , Miócitos Cardíacos/fisiologia , Receptores Adrenérgicos beta 1/fisiologia , Sistemas do Segundo Mensageiro/fisiologia , Regiões 3' não Traduzidas/fisiologia , Adenilil Ciclases/fisiologia , Animais , Apoptose , Células Cultivadas , Proteínas Quinases Dependentes de AMP Cíclico/fisiologia , Progressão da Doença , Regulação da Expressão Gênica/efeitos dos fármacos , Genes Reporter , Fatores de Troca do Nucleotídeo Guanina/fisiologia , Masculino , Metoprolol/farmacologia , Metoprolol/uso terapêutico , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , MicroRNAs/genética , Miocárdio/metabolismo , Miocárdio/patologia , Miócitos Cardíacos/efeitos dos fármacos , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes de Fusão/genética
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