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1.
Int J Mol Sci ; 22(5)2021 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-33652988

RESUMO

In this Review, we briefly describe the basic virology and pathogenesis of SARS-CoV-2, highlighting how stem cell technology and organoids can contribute to the understanding of SARS-CoV-2 cell tropisms and the mechanism of disease in the human host, supporting and clarifying findings from clinical studies in infected individuals. We summarize here the results of studies, which used these technologies to investigate SARS-CoV-2 pathogenesis in different organs. Studies with in vitro models of lung epithelia showed that alveolar epithelial type II cells, but not differentiated lung alveolar epithelial type I cells, are key targets of SARS-CoV-2, which triggers cell apoptosis and inflammation, while impairing surfactant production. Experiments with human small intestinal organoids and colonic organoids showed that the gastrointestinal tract is another relevant target for SARS-CoV-2. The virus can infect and replicate in enterocytes and cholangiocytes, inducing cell damage and inflammation. Direct viral damage was also demonstrated in in vitro models of human cardiomyocytes and choroid plexus epithelial cells. At variance, endothelial cells and neurons are poorly susceptible to viral infection, thus supporting the hypothesis that neurological symptoms and vascular damage result from the indirect effects of systemic inflammatory and immunological hyper-responses to SARS-CoV-2 infection.


Assuntos
/patologia , Organoides/virologia , Células-Tronco/virologia , Animais , Apoptose , Sistema Cardiovascular/citologia , Sistema Cardiovascular/patologia , Sistema Cardiovascular/virologia , Sistema Nervoso Central/citologia , Sistema Nervoso Central/patologia , Sistema Nervoso Central/virologia , Trato Gastrointestinal/citologia , Trato Gastrointestinal/patologia , Trato Gastrointestinal/virologia , Humanos , Inflamação/patologia , Inflamação/virologia , Pulmão/citologia , Pulmão/patologia , Pulmão/virologia , Organoides/patologia , Células-Tronco/patologia , Tropismo Viral , Internalização do Vírus
2.
Methods Mol Biol ; 2269: 125-137, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33687676

RESUMO

Ex vivo neuroretina cultures closely resemble in vivo conditions, retaining the complex neuroretina cells dynamics, connections, and functionality, under controlled conditions. Therefore, these models have allowed advancing in the knowledge of retinal physiology and pathobiology over the years. Furthermore, the ex vivo neuroretina models represent an adequate tool for evaluating stem cell therapies over neuroretinal degeneration processes.Here, we describe a physically separated co-culture of neuroretina explants with stem cells to evaluate the effect of stem cells paracrine properties on spontaneous neuroretinal degeneration.


Assuntos
Modelos Neurológicos , Comunicação Parácrina , Retina , Degeneração Retiniana , Células-Tronco , Animais , Técnicas de Cocultura , Humanos , Retina/metabolismo , Retina/patologia , Degeneração Retiniana/metabolismo , Degeneração Retiniana/patologia , Células-Tronco/metabolismo , Células-Tronco/patologia
3.
Nat Commun ; 12(1): 1502, 2021 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-33686070

RESUMO

It is unclear how genetic aberrations impact the state of nascent tumour cells and their microenvironment. BRCA1 driven triple negative breast cancer (TNBC) has been shown to arise from luminal progenitors yet little is known about how BRCA1 loss-of-function (LOF) and concomitant mutations affect the luminal progenitor cell state. Here we demonstrate how time-resolved single-cell profiling of genetically engineered mouse models before tumour formation can address this challenge. We found that perturbing Brca1/p53 in luminal progenitors induces aberrant alveolar differentiation pre-malignancy accompanied by pro-tumourigenic changes in the immune compartment. Unlike alveolar differentiation during gestation, this process is cell autonomous and characterised by the dysregulation of transcription factors driving alveologenesis. Based on our data we propose a model where Brca1/p53 LOF inadvertently promotes a differentiation program hardwired in luminal progenitors, highlighting the deterministic role of the cell-of-origin and offering a potential explanation for the tissue specificity of BRCA1 tumours.


Assuntos
Proteína BRCA1/genética , Transformação Celular Neoplásica/genética , Neoplasias Mamárias Experimentais/genética , Fenobarbital/metabolismo , Análise de Célula Única/métodos , Células-Tronco/patologia , Animais , Proteína BRCA1/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Comunicação Celular/fisiologia , Diferenciação Celular/fisiologia , Transformação Celular Neoplásica/metabolismo , Feminino , Humanos , Neoplasias Mamárias Experimentais/metabolismo , Neoplasias Mamárias Experimentais/patologia , Camundongos , Mutação , Células-Tronco/fisiologia , Microambiente Tumoral/genética , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
4.
Int J Mol Med ; 47(4): 1, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33537804

RESUMO

Quercetin (Quer) is a typical antioxidant flavonoid from plants that is involved in bone metabolism, as well as in the progression of inflammatory diseases. Elevated levels of tumor necrosis factor­α (TNF­α), a typical pro­inflammatory cytokine, can affect osteogenesis. In the present study, TNF­α was used to establish an in vitro model of periodontitis. The effects of Quer on, as well as its potential role in the osteogenic response of human periodontal ligament stem cells (hPDLSCs) under TNF­α­induced inflammatory conditions and the underlying mechanisms were then investigated. Within the appropriate concentration range, Quer did not exhibit any cytotoxicity. More importantly, Quer significantly attenuated the TNF­α induced the suppression of osteogenesis­related genes and proteins, alkaline phosphatase (ALP) activity and mineralized matrix in the hPDLSCs. These findings were associated with the fact that Quer inhibited the activation of the NF­κB signaling pathway, as well as the expression of NLRP3 inflammation­associated proteins in the inflammatory microenvironment. Moreover, the silencing of NLRP3 by small interfering RNA (siRNA) was found to protect the hPDLSCs against TNF­α­induced osteogenic damage, which was in accordance with the effects of Quer. On the whole, the present study demonstrates that Quer reduces the impaired osteogenesis of hPDLSCs under TNF­α­induced inflammatory conditions by inhibiting the NF­κB/NLRP3 inflammasome pathway. Thus, Quer may prove to be a potential remedy against periodontal bone defects.


Assuntos
Inflamassomos/metabolismo , NF-kappa B/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Osteogênese/efeitos dos fármacos , Ligamento Periodontal/patologia , Quercetina/farmacologia , Células-Tronco/patologia , Fator de Necrose Tumoral alfa/toxicidade , Adolescente , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Citocinas/metabolismo , Regulação para Baixo/efeitos dos fármacos , Inativação Gênica/efeitos dos fármacos , Humanos , Mediadores da Inflamação/metabolismo , Substâncias Protetoras/farmacologia , Transdução de Sinais/efeitos dos fármacos , Células-Tronco/efeitos dos fármacos , Adulto Jovem
5.
Ecotoxicol Environ Saf ; 210: 111892, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33429317

RESUMO

Human activities have generated air pollution, with extremely small particles (PM 2.5, particulate matter less than 2.5 µm in diameter) and liquid droplets, which become a menace to human health. Among the pollutants, polycyclic aromatic hydrocarbons (PAHs), which enhance the risks of pulmonary dysfunction and cancer development, have been extensively studied. Numerous studies have addressed the effects of PAHs on the respiratory system, whereas the effects on lung stem/progenitor cells remain unknown. Here, we provide evidence that benzo[a]pyrene (BaP), a major toxic PAH, induces fibrotic changes with a loss of α-1,6-fucosylation in CD54+CD157+CD45- cells (lung stem cells). In studies with aryl hydrocarbon receptor (AHR) antagonist, we found that these effects by BaP are independent of the canonical AHR pathway. In addition, these BaP-induced fibrotic changes are reduced by TGF-ß antagonist, suggesting an alternative pathway of BaP toxicity is different from other PAH/AHR signaling pathways. Finally, it was observed that BaP impairs the spheroid formation and the podoplanin expression of CD54+CD157+CD45- cells, indicating that BaP suppresses the differentiation of lung stem cells. Taken together, our findings reveal specific BaP-induced injuries in CD54+CD157+CD45- cells.


Assuntos
Poluentes Atmosféricos/toxicidade , Benzo(a)pireno/toxicidade , Pulmão/citologia , Células-Tronco/efeitos dos fármacos , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/antagonistas & inibidores , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Fibrose , Camundongos , Receptores de Hidrocarboneto Arílico/antagonistas & inibidores , Células-Tronco/patologia , Fator de Crescimento Transformador beta/antagonistas & inibidores
6.
Cells ; 10(1)2021 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-33430424

RESUMO

The new strain of coronavirus (severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2)) emerged in 2019 and hence is often referred to as coronavirus disease 2019 (COVID-19). This disease causes hypoxic respiratory failure and acute respiratory distress syndrome (ARDS), and is considered as the cause of a global pandemic. Very limited reports in addition to ex vivo model systems are available to understand the mechanism of action of this virus, which can be used for testing of any drug efficacy against virus infectivity. COVID-19 induces tissue stem cell loss, resulting inhibition of epithelial repair followed by inflammatory fibrotic consequences. Development of clinically relevant models is important to examine the impact of the COVID-19 virus in tissue stem cells among different organs. In this review, we discuss ex vivo experimental models available to study the effect of COVID-19 on tissue stem cells.


Assuntos
/patologia , Modelos Teóricos , Células-Tronco/patologia , Células Cultivadas , Humanos
7.
Stem Cell Rev Rep ; 17(1): 214-230, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33403490

RESUMO

The COVID-19 pandemic has profoundly influenced public health and contributed to global economic divergences of unprecedented dimensions. Due to the high prevalence and mortality rates, it is then expected that the consequence and public health challenges will last for long periods. The rapid global spread of COVID-19 and lack of enough data regarding the virus pathogenicity multiplies the complexity and forced governments to react quickly against this pandemic. Stem cells represent a small fraction of cells located in different tissues. These cells play a critical role in the regeneration and restoration of injured sites. Because of their specific niche and a limited number of stem cells, the key question is whether there are different anti-viral mechanisms against viral infection notably COVID-19. Here, we aimed to highlight the intrinsic antiviral resistance in different stem cells against viral infection. These data could help us to understand the possible viral infections in different stem cells and the activation of specific molecular mechanisms upon viral entrance.


Assuntos
/terapia , Pandemias , Transplante de Células-Tronco , Viroses/terapia , /virologia , Surtos de Doenças/prevenção & controle , Humanos , Células-Tronco/patologia , Viroses/virologia
8.
Nat Cell Biol ; 23(2): 184-197, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33462395

RESUMO

The transition zones of the squamous and columnar epithelia constitute hotspots for the emergence of cancer, often preceded by metaplasia, in which one epithelial type is replaced by another. It remains unclear how the epithelial spatial organization is maintained and how the transition zone niche is remodelled during metaplasia. Here we used single-cell RNA sequencing to characterize epithelial subpopulations and the underlying stromal compartment of endo- and ectocervix, encompassing the transition zone. Mouse lineage tracing, organoid culture and single-molecule RNA in situ hybridizations revealed that the two epithelia derive from separate cervix-resident lineage-specific stem cell populations regulated by opposing Wnt signals from the stroma. Using a mouse model of cervical metaplasia, we further show that the endocervical stroma undergoes remodelling and increases expression of the Wnt inhibitor Dickkopf-2 (DKK2), promoting the outgrowth of ectocervical stem cells. Our data indicate that homeostasis at the transition zone results from divergent stromal signals, driving the differential proliferation of resident epithelial lineages.


Assuntos
Colo do Útero/patologia , Epitélio/patologia , Homeostase , Via de Sinalização Wnt , Adenocarcinoma/genética , Adenocarcinoma/patologia , Animais , Biomarcadores Tumorais/metabolismo , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Diferenciação Celular , Linhagem da Célula , Microambiente Celular , Receptores ErbB/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Queratinas/metabolismo , Metaplasia , Camundongos Endogâmicos C57BL , Organoides/patologia , Receptores Notch/metabolismo , Células-Tronco/patologia , Células Estromais/patologia , Transcrição Genética , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/patologia
9.
Biomed Pharmacother ; 134: 111129, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33348308

RESUMO

Ulcerative colitis (UC) is an inflammatory bowel disease with complex pathogenesis, which is affected by genetic factors, intestinal immune status and intestinal microbial homeostasis. Intestinal epithelial barrier defect is crucial to the development of UC. Berberine, extracted from Chinese medicine, can identify bitter taste receptor on intestinal Tuft cells and activate IL-25-ILC2-IL-13 immune pathway to impair damaged intestinal tract by promoting differentiation of intestinal stem cells, which might be a potential approach for the treatment of UC.


Assuntos
Anti-Inflamatórios/uso terapêutico , Berberina/uso terapêutico , Colite Ulcerativa/tratamento farmacológico , Colo/efeitos dos fármacos , Mucosa Intestinal/efeitos dos fármacos , Células-Tronco/efeitos dos fármacos , Animais , Colite Ulcerativa/imunologia , Colite Ulcerativa/metabolismo , Colite Ulcerativa/patologia , Colo/imunologia , Colo/metabolismo , Colo/patologia , Citocinas/metabolismo , Humanos , Mediadores da Inflamação/metabolismo , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Receptores Acoplados a Proteínas-G/agonistas , Receptores Acoplados a Proteínas-G/metabolismo , Transdução de Sinais , Células-Tronco/imunologia , Células-Tronco/metabolismo , Células-Tronco/patologia
10.
Nat Metab ; 2(12): 1482-1497, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33324010

RESUMO

White and beige adipocytes in subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT) are maintained by proliferation and differentiation of adipose progenitor cells (APCs). Here we use mice with tissue-specific telomerase reverse transcriptase (TERT) gene knockout (KO), which undergo premature telomere shortening and proliferative senescence in APCs, to investigate the effect of over-nutrition on APC exhaustion and metabolic dysfunction. We find that TERT KO in the Pdgfra+ cell lineage results in adipocyte hypertrophy, inflammation and fibrosis in SAT, while TERT KO in the Pdgfrb+ lineage leads to adipocyte hypertrophy in both SAT and VAT. Systemic insulin resistance is observed in both KO models and is aggravated by a high-fat diet. Analysis of human biopsies demonstrates that telomere shortening in SAT is associated with metabolic disease progression after bariatric surgery. Our data indicate that over-nutrition can promote APC senescence and provide a mechanistic link between ageing, obesity and diabetes.


Assuntos
Adipócitos/patologia , Envelhecimento/patologia , Doenças Metabólicas/patologia , Células-Tronco/patologia , Homeostase do Telômero , Adipócitos Bege/metabolismo , Adipócitos Brancos/metabolismo , Animais , Diferenciação Celular , Linhagem da Célula/genética , Proliferação de Células , Dieta Hiperlipídica , Feminino , Humanos , Resistência à Insulina/genética , Gordura Intra-Abdominal , Masculino , Doenças Metabólicas/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/genética , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Gordura Subcutânea/metabolismo , Gordura Subcutânea/patologia , Telomerase/genética , Telomerase/metabolismo
11.
J Leukoc Biol ; 108(4): 1037-1050, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33311847

RESUMO

Bone destruction in inflammatory osteolytic diseases including periodontitis is related to excessive activity of osteoclasts (OC), which originate from precursor cells of the myeloid lineage, termed osteoclast precursors (OCP). In contrast to ample knowledge that we currently have on mature OC, little is known about OCP and their regulation during bacterial infection. Therefore, this study aimed to identify and characterize OCP following chronic infection with a periodontal bacteria Porphyromonas gingivalis (Pg). We used a micro-osmotic pump to continually release Pg subcutaneously in a murine model. Two weeks after Pg infection, the frequency of CD11b+c-fms+Ly6Chi population is significantly elevated within the bone marrow, spleen and peripheral blood. In vitro and in vivo studies identified these cells as the OCP-containing population and Pg infection significantly enhanced the osteoclastogenic activity of these cells. Furthermore, mRNA sequencing analysis indicated a unique gene and pathway profile in CD11b+c-fms+Ly6Chi population following Pg infection, with changes in genes and pathways related to OC differentiation, cell proliferation and apoptosis, inflammatory response, phagocytosis and immunity, as well as antigen processing and presentation. Moreover, using IL-6 knockout mice, we found that IL-6 is important for Pg-induced accumulation of CD11b+c-fms+Ly6Chi population from the bone marrow and periphery. Our results provide new insights into the characterization and regulation of OCP following a chronic bacterial infection. This knowledge is relevant to the understanding of the pathogenesis of bacteria-induced bone loss, and to the identification of potential therapeutic targets of bone loss diseases.


Assuntos
Infecções por Bacteroidaceae/imunologia , Diferenciação Celular/imunologia , Osteoclastos/imunologia , Osteólise/imunologia , Porphyromonas gingivalis/imunologia , Células-Tronco/imunologia , Animais , Infecções por Bacteroidaceae/genética , Infecções por Bacteroidaceae/patologia , Diferenciação Celular/genética , Doença Crônica , Modelos Animais de Doenças , Interleucina-6/genética , Interleucina-6/imunologia , Camundongos , Camundongos Knockout , Osteoclastos/patologia , Osteólise/genética , Osteólise/microbiologia , Osteólise/patologia , Células-Tronco/patologia
12.
Ecotoxicol Environ Saf ; 205: 111283, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32977282

RESUMO

Fine particulate matter (PM2.5) airborne pollution increases the risk of chronic respiratory diseases, such as idiopathic pulmonary fibrosis (IPF), which is characterized by non-specific inflammation of the interstitial lung and extensive deposition of collagen fibers. Type 2 alveolar epithelial cells (AEC2s) are alveolar stem cells in the adult lung that contribute to the lung repair process through complex signaling. Our previous studies demonstrated that OGG1, a kind of DNA repair enzyme, have a critical role in protecting cells from oxidative damage and apoptosis induced by PM2.5, but the contribution of OGG1 in proliferation and self-renewal of AEC2s is not known. Here, we constructed OGG1-/-mice to test the effect and mechanism of OGG1 on PM2.5-induced pulmonary fibrosis and injury in vivo. We detected proliferation and self-renewal of OGG1 overexpression or OGG1 knockout AEC2s after PM2.5 injury by flow cytometry and clone formation. We observed that knockout of OGG1 aggravated pulmonary fibrosis, oxidative stress, and AEC2 cell death in PM2.5-injured mice. In addition, OGG1 is required for the proliferation and renewal of AEC2s after PM2.5 injury. Overexpression of OGG1 promotes the proliferation and self-renewal of AEC2s by inhibiting PM2.5-mediated oxidative stress and NF-κB signaling hyperactivation in vitro. Furthermore, NF-κB inhibitors promoted proliferation and self-renewal of OGG1-deficient AEC2s cells after PM2.5 injury, and attenuated PM2.5-induced pulmonary fibrosis and injury in mice. These data establish OGG1 as a regulator of NF-κB signal that serves to regulate AEC2 cell proliferation and self-renewal, and suggest a mechanism that inhibition of the NF-κB signaling pathway may represent a potential therapeutic strategy for IPF patients with low-expression of OGG1.


Assuntos
Poluentes Atmosféricos/toxicidade , Células Epiteliais Alveolares/efeitos dos fármacos , Autorrenovação Celular/genética , DNA Glicosilases/metabolismo , Material Particulado/toxicidade , Fibrose Pulmonar/induzido quimicamente , Células-Tronco/efeitos dos fármacos , Células Epiteliais Alveolares/metabolismo , Células Epiteliais Alveolares/patologia , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , DNA Glicosilases/genética , Humanos , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Pulmão/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , NF-kappa B/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/genética , Fibrose Pulmonar/genética , Fibrose Pulmonar/patologia , Transdução de Sinais , Células-Tronco/metabolismo , Células-Tronco/patologia
13.
Arch Biochem Biophys ; 692: 108531, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-32745464

RESUMO

Adipose-derived stem cell (ADSC) therapy is a promising treatment strategy for wound healing; however, the mechanism underlying this effect remains unclear. In the present study, we aimed to explore the influence of ADSC-derived VEGF on diabetic wounds and its role in modulating endothelial progenitor cells. The effect of ADSCs and ADSC-derived VEGF in vivo was investigated using a diabetic wound healing model, and inflammatory factors, such as IL-6, IL-10, and TNF-α, were detected. RT-qPCR and western blot analysis were used to detect the expression of downstream targets. In addition, the role of ADSC-derived VEGF in modulating endothelial progenitor cells (EPCs) was investigated using EdU assay, CD-31 immunofluorescence, and Transwell assay in vitro. The results show that ADSCs accelerated diabetic wound tissue closure and decreased the expression of inflammatory factors, such as IL-6, IL-10, and TNF-α. Further molecular mechanism studies indicated that coculturing EPCs with ADSC--conditioned medium enhanced the proliferation, mobilization and differentiation of EPCs into endothelial cells. This enhancement was inhibited when the expression of the VEGF downstream signal molecules VEGFR2, PLCγ, and ERK1/ERK2 was blocked, indicating that ADSCs might accelerate diabetic wound healing through the recruitment and differentiation of EPCs mediated by VEGF. Overall, the results of the study revealed that ADSCs could promote diabetic wound healing through the recruitment and differentiation of EPCs via angiogenesis effects regulated by the VEGF-PLCγ-ERK1/ERK2 pathway and suppression of the inflammatory response. In addition, it will be helpful to establish further understanding of ADSC therapy for clinical application.


Assuntos
Tecido Adiposo/metabolismo , Diabetes Mellitus Experimental , Angiopatias Diabéticas , Sistema de Sinalização das MAP Quinases , Fosfolipase C gama/metabolismo , Transplante de Células-Tronco , Células-Tronco/metabolismo , Fator A de Crescimento do Endotélio Vascular/biossíntese , Cicatrização , Tecido Adiposo/patologia , Aloenxertos , Animais , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Experimental/terapia , Angiopatias Diabéticas/metabolismo , Angiopatias Diabéticas/patologia , Angiopatias Diabéticas/terapia , Ratos , Ratos Sprague-Dawley , Células-Tronco/patologia
14.
Oncogene ; 39(32): 5468-5478, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32616888

RESUMO

Melanoma stem cells (MSCs) are characterized by their unique cell surface proteins and aberrant signaling pathways. These stemness properties are either in a causal or consequential relationship to melanoma progression, treatment resistance and recurrence. The functional analysis of CD133+ and CD133- cells in vitro and in vivo revealed that melanoma progression and treatment resistance are the consequences of CD133 signal to PI3K pathway. CD133 signal to PI3K pathway drives two downstream pathways, the PI3K/Akt/MDM2 and the PI3K/Akt/MKP-1 pathways. Activation of PI3K/Akt/MDM2 pathway results in the destabilization of p53 protein, while the activation of PI3K/Akt/MKP-1 pathway results in the inhibition of mitogen-activated protein kinases (MAPKs) JNK and p38. Activation of both pathways leads to the inhibition of fotemustine-induced apoptosis. Thus, the disruption of CD133 signal to PI3K pathway is essential to overcome Melanoma resistance to fotemustine. The pre-clinical verification of in vitro data using xenograft mouse model of MSCs confirmed the clinical relevance of CD133 signal as a therapeutic target for melanoma treatment. In conclusion, our study provides an insight into the mechanisms regulating MSCs growth and chemo-resistance and suggested a clinically relevant approach for melanoma treatment.


Assuntos
Antígeno AC133/metabolismo , Melanoma/patologia , Fosfatidilinositol 3-Quinases/metabolismo , Células-Tronco/metabolismo , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Fosfatase 1 de Especificidade Dupla/metabolismo , Humanos , Melanoma/tratamento farmacológico , Melanoma/metabolismo , Compostos de Nitrosoureia/farmacologia , Compostos Organofosforados/farmacologia , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Transdução de Sinais , Células-Tronco/efeitos dos fármacos , Células-Tronco/patologia
15.
Sci Rep ; 10(1): 9393, 2020 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-32523078

RESUMO

Three-dimensional (3D) organoid culture holds great promises in cancer precision medicine. However, Matrigel and stem cell-stimulating supplements are necessary for culturing 3D organoid cells. It costs a lot of money and consumes more time and effort compared with 2D cultured cells. Therefore, the establishment of cheaper and Matrigel-free organoid culture that can maintain the characteristics of a part of 3D organoids is demanded. In the previous study, we established a dog bladder cancer (BC) 3D organoid culture system by using their urine samples. Here, we successfully isolated cells named "2.5D organoid" from multiple strains of dog BC 3D organoids using 2.5 organoid media. The cell proliferation speed of 2.5D organoids was faster than parental 3D organoid cells. The expression pattern of stem cell markers was close to 3D organoids. Injection of 2.5D organoid cells into immunodeficient mice formed tumors and showed the histopathological characteristics of urothelial carcinoma similar to the injection of dog BC 3D organoids. The 2.5D organoids had a similar sensitivity profile for anti-cancer drug treatment to their parental 3D organoids. These data suggest that our established 2.5D organoid culture method might become a reasonable and useful tool instead of 3D organoids in dog BC research and therapy.


Assuntos
Organoides/patologia , Neoplasias da Bexiga Urinária/patologia , Animais , Antineoplásicos/farmacologia , Biomarcadores Tumorais/metabolismo , Técnicas de Cultura de Células/métodos , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/fisiologia , Cães , Ensaios de Seleção de Medicamentos Antitumorais/métodos , Masculino , Camundongos , Organoides/efeitos dos fármacos , Organoides/metabolismo , Células-Tronco/efeitos dos fármacos , Células-Tronco/metabolismo , Células-Tronco/patologia , Células Tumorais Cultivadas , Neoplasias da Bexiga Urinária/tratamento farmacológico
16.
Nat Cell Biol ; 22(7): 779-790, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32451440

RESUMO

Tissue stem cells are the cell of origin for many malignancies. Metabolites regulate the balance between self-renewal and differentiation, but whether endogenous metabolic pathways or nutrient availability predispose stem cells towards transformation remains unknown. Here, we address this question in epidermal stem cells (EpdSCs), which are a cell of origin for squamous cell carcinoma. We find that oncogenic EpdSCs are serine auxotrophs whose growth and self-renewal require abundant exogenous serine. When extracellular serine is limited, EpdSCs activate de novo serine synthesis, which in turn stimulates α-ketoglutarate-dependent dioxygenases that remove the repressive histone modification H3K27me3 and activate differentiation programmes. Accordingly, serine starvation or enforced α-ketoglutarate production antagonizes squamous cell carcinoma growth. Conversely, blocking serine synthesis or repressing α-ketoglutarate-driven demethylation facilitates malignant progression. Together, these findings reveal that extracellular serine is a critical determinant of EpdSC fate and provide insight into how nutrient availability is integrated with stem cell fate decisions during tumour initiation.


Assuntos
Carcinoma de Células Escamosas/patologia , Transformação Celular Neoplásica/patologia , Células Epidérmicas/patologia , Ácidos Cetoglutáricos/metabolismo , Serina/metabolismo , Células-Tronco/patologia , Animais , Carcinoma de Células Escamosas/metabolismo , Diferenciação Celular , Transformação Celular Neoplásica/metabolismo , Células Cultivadas , Células Epidérmicas/metabolismo , Feminino , Humanos , Masculino , Camundongos , Células-Tronco/metabolismo
17.
Oncogene ; 39(24): 4756-4769, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32427988

RESUMO

Pak1 (serine/threonine p21-activated kinases) was previously reported to have oncogenic activity in several cancers. However, its roles in the cancer microenvironment are poorly understood. We demonstrated that Pak1 expression in Langerhans cells (LCs) is essential for the maintenance of epidermal stem cells and skin tumor development. We found that PAK1 is localized in LCs by immunohistochemistry. Furthermore, the number of LCs significantly decreased in MSM/Ms Pak1 homozygous knockout mice (MSM/Ms-Pak1-/-). F1 hybrid (FVB/N×MSM/Ms) Pak1 heterozygous knockout mice (F1-Pak1+/-) had increased numbers of Th17 cells in the skin. Therefore, Pak1 knockdown cells were prepared using LC-derived XS52 cells (XS52-Pak1KD) and co-cultured with keratinocyte-derived C5N cells. As a result, XS52-Pak1KD cell supernatants promoted C5N cell proliferation. We then carried out DMBA/TPA skin carcinogenesis experiments using F1-Pak1+/- mice. Of note, F1-Pak1+/- mice exhibited stronger resistance to skin tumors than control mice. F1-Pak1+/- mice had fewer epidermal stem cells in the skin bulge. Our study suggested that Pak1 regulates the epidermal stem cell number by changing the properties of LCs and functions in skin carcinogenesis. We clarified a novel role of Pak1 in regulating LCs as a potential therapeutic target in skin immune disease and carcinogenesis.


Assuntos
Carcinogênese/metabolismo , Epiderme/metabolismo , Células de Langerhans/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias Cutâneas/metabolismo , Células-Tronco/metabolismo , Quinases Ativadas por p21/metabolismo , Animais , Carcinogênese/genética , Carcinogênese/patologia , Epiderme/patologia , Células de Langerhans/patologia , Camundongos , Camundongos Knockout , Proteínas de Neoplasias/genética , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia , Células-Tronco/patologia , Quinases Ativadas por p21/genética
18.
PLoS One ; 15(4): e0229593, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32324791

RESUMO

Acute myeloid leukaemia (AML) is characterised by phenotypic heterogeneity, which we hypothesise is a consequence of deregulated differentiation with transcriptional reminiscence of the normal compartment or cell-of-origin. Here, we propose a classification system based on normal myeloid progenitor cell subset-associated gene signatures (MAGS) for individual assignments of AML subtypes. We generated a MAGS classifier including the progenitor compartments CD34+/CD38- for haematopoietic stem cells (HSCs), CD34+/CD38+/CD45RA- for megakaryocyte-erythroid progenitors (MEPs), and CD34+/CD38+/CD45RA+ for granulocytic-monocytic progenitors (GMPs) using regularised multinomial regression with three discrete outcomes and an elastic net penalty. The regularisation parameters were chosen by cross-validation, and MAGS assignment accuracy was validated in an independent data set (N = 38; accuracy = 0.79) of sorted normal myeloid subpopulations. The prognostic value of MAGS assignment was studied in two clinical cohorts (TCGA: N = 171; GSE6891: N = 520) and had a significant prognostic impact. Furthermore, multivariate Cox regression analysis using the MAGS subtype, FAB subtype, cytogenetics, molecular genetics, and age as explanatory variables showed independent prognostic value. Molecular characterisation of subtypes by differential gene expression analysis, gene set enrichment analysis, and mutation patterns indicated reduced proliferation and overrepresentation of RUNX1 and IDH2 mutations in the HSC subtype; increased proliferation and overrepresentation of CEBPA mutations in the MEP subtype; and innate immune activation and overrepresentation of WT1 mutations in the GMP subtype. We present a differentiation-dependent classification system for AML subtypes with distinct pathogenetic and prognostic importance that can help identify candidates poorly responding to combination chemotherapy and potentially guide alternative treatments.


Assuntos
Células-Tronco Hematopoéticas/metabolismo , Leucemia Mieloide Aguda/genética , Células Mieloides/metabolismo , Células-Tronco/metabolismo , ADP-Ribosil Ciclase 1/genética , Antígenos CD34/genética , Diferenciação Celular/genética , Linhagem da Célula/genética , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Células-Tronco Hematopoéticas/patologia , Humanos , Isocitrato Desidrogenase/genética , Leucemia Mieloide Aguda/patologia , Antígenos Comuns de Leucócito/genética , Masculino , Pessoa de Meia-Idade , Mutação/genética , Células Mieloides/patologia , Análise de Componente Principal , Análise de Regressão , Células-Tronco/patologia , Proteínas WT1/genética
19.
Muscle Nerve ; 62(1): 128-136, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32304242

RESUMO

INTRODUCTION: Emery-Dreifuss muscular dystrophy (EDMD) is a disease characterized by skeletal muscle wasting, major tendon contractures, and cardiac conduction defects. Mutations in the gene encoding emerin cause EDMD1. Our previous studies suggested that emerin activation of histone deacetylase 3 (HDAC3) to reduce histone 4-lysine 5 (H4K5) acetylation (ac) is important for myogenic differentiation. METHODS: Pharmacological inhibitors (Nu9056, L002) of histone acetyltransferases targeting acetylated H4K5 were used to test whether increased acetylated H4K5 was responsible for the impaired differentiation seen in emerin-deficient myogenic progenitors. RESULTS: Nu9056 and L002 rescued impaired differentiation in emerin deficiency. SRT1720, which inhibits the nicotinamide adenine dinucleotide (NAD)+ -dependent deacetylase sirtuin 1 (SIRT1), failed to rescue myotube formation. DISCUSSION: We conclude that emerin regulation of HDAC3 activity to affect H4K5 acetylation dynamics is important for myogenic differentiation. Targeting H4K5ac dynamics represents a potential new strategy for ameliorating the skeletal muscle wasting seen in EDMD1.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Histona Acetiltransferases/antagonistas & inibidores , Distrofia Muscular de Emery-Dreifuss/tratamento farmacológico , Distrofia Muscular de Emery-Dreifuss/patologia , Células-Tronco/efeitos dos fármacos , Tiazóis/uso terapêutico , Animais , Diferenciação Celular/fisiologia , Células Cultivadas , Histona Acetiltransferases/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Células-Tronco/patologia , Tiazóis/farmacologia
20.
Proc Natl Acad Sci U S A ; 117(19): 10357-10367, 2020 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-32345720

RESUMO

Cystic fibrosis (CF) is a recessive disease caused by mutations in the CF transmembrane conductance regulator (CFTR) gene. The most common symptoms include progressive lung disease and chronic digestive conditions. CF is the first human genetic disease to benefit from having five different species of animal models. Despite the phenotypic differences among the animal models and human CF, these models have provided invaluable insight into understanding disease mechanisms at the organ-system level. Here, we identify a member of the ABCC4 family, CG5789, that has the structural and functional properties expected for encoding the Drosophila equivalent of human CFTR, and thus refer to it as Drosophila CFTR (Dmel\CFTR). We show that knockdown of Dmel\CFTR in the adult intestine disrupts osmotic homeostasis and displays CF-like phenotypes that lead to intestinal stem cell hyperplasia. We also show that expression of wild-type human CFTR, but not mutant variants of CFTR that prevent plasma membrane expression, rescues the mutant phenotypes of Dmel\CFTR Furthermore, we performed RNA sequencing (RNA-Seq)-based transcriptomic analysis using Dmel\CFTR fly intestine and identified a mucin gene, Muc68D, which is required for proper intestinal barrier protection. Altogether, our findings suggest that Drosophila can be a powerful model organism for studying CF pathophysiology.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Fibrose Cística/patologia , Modelos Animais de Doenças , Proteínas de Drosophila/metabolismo , Intestinos/patologia , Mutação , Células-Tronco/patologia , Animais , Fibrose Cística/genética , Fibrose Cística/metabolismo , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Proteínas de Drosophila/genética , Drosophila melanogaster , Sequenciamento de Nucleotídeos em Larga Escala , Homeostase , Humanos , Mucinas/genética , Mucinas/metabolismo , Fenótipo , Células-Tronco/metabolismo
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