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1.
Cell Death Differ ; 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38714880

RESUMO

Obesity is endemic to many developed countries. Overweight or obesity is associated with an increased risk of developing cancer. Dysfunctional adipose tissue alters cancer cell proliferation and migration; however, whether and how neoplastic epithelial cells communicate with adipose tissue and the underlying mechanism are less clear. BTG3 is a member of the anti-proliferative BTG/Tob family and functions as a tumor suppressor. Here, we demonstrated that BTG3 levels are downregulated in basal cell carcinoma and squamous cell carcinoma compared to normal skin tissue, and Btg3 knockout in mice augmented the development of papilloma in a mouse model of DMBA/TPA-induced skin carcinogenesis. Mechanistically, BTG3-knockout keratinocytes promoted adipocyte differentiation mainly through the release of IL1α, IL10, and CCL4, as a result of elevated NF-κB activity. These adipocytes produced CCL20 and FGF7 in a feedback loop to promote keratinocyte migration. Thus, our findings showcased the role of BTG3 in guarding the interplay between keratinocytes and adjacent adipocytes, and identified the underlying neoplastic molecular mediators that may serve as possible targets in the treatment of skin cancer.

2.
Nat Commun ; 14(1): 7249, 2023 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-37945565

RESUMO

The gut microbiome and its metabolites are increasingly implicated in several cardiovascular diseases, but their role in human myocardial infarction (MI) injury responses have yet to be established. To address this, we examined stool samples from 77 ST-elevation MI (STEMI) patients using 16 S V3-V4 next-generation sequencing, metagenomics and machine learning. Our analysis identified an enriched population of butyrate-producing bacteria. These findings were then validated using a controlled ischemia/reperfusion model using eight nonhuman primates. To elucidate mechanisms, we inoculated gnotobiotic mice with these bacteria and found that they can produce beta-hydroxybutyrate, supporting cardiac function post-MI. This was further confirmed using HMGCS2-deficient mice which lack endogenous ketogenesis and have poor outcomes after MI. Inoculation increased plasma ketone levels and provided significant improvements in cardiac function post-MI. Together, this demonstrates a previously unknown role of gut butyrate-producers in the post-MI response.


Assuntos
Infarto do Miocárdio , Infarto do Miocárdio com Supradesnível do Segmento ST , Humanos , Animais , Camundongos , Butiratos/metabolismo , Coração , Corpos Cetônicos
3.
Circulation ; 148(18): 1395-1409, 2023 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-37732466

RESUMO

BACKGROUND: Remuscularization of the mammalian heart can be achieved after cell transplantation of human induced pluripotent stem cell (hiPSC)-derived cardiomyocytes (CMs). However, several hurdles remain before implementation into clinical practice. Poor survival of the implanted cells is related to insufficient vascularization, and the potential for fatal arrhythmogenesis is associated with the fetal cell-like nature of immature CMs. METHODS: We generated 3 lines of hiPSC-derived endothelial cells (ECs) and hiPSC-CMs from 3 independent donors and tested hiPSC-CM sarcomeric length, gap junction protein, and calcium-handling ability in coculture with ECs. Next, we examined the therapeutic effect of the cotransplantation of hiPSC-ECs and hiPSC-CMs in nonobese diabetic-severe combined immunodeficiency (NOD-SCID) mice undergoing myocardial infarction (n≥4). Cardiac function was assessed by echocardiography, whereas arrhythmic events were recorded using 3-lead ECGs. We further used healthy non-human primates (n=4) with cell injection to study the cell engraftment, maturation, and integration of transplanted hiPSC-CMs, alone or along with hiPSC-ECs, by histological analysis. Last, we tested the cell therapy in ischemic reperfusion injury in non-human primates (n=4, 3, and 4 for EC+CM, CM, and control, respectively). Cardiac function was evaluated by echocardiography and cardiac MRI, whereas arrhythmic events were monitored by telemetric ECG recorders. Cell engraftment, angiogenesis, and host-graft integration of human grafts were also investigated. RESULTS: We demonstrated that human iPSC-ECs promote the maturity and function of hiPSC-CMs in vitro and in vivo. When cocultured with ECs, CMs showed more mature phenotypes in cellular structure and function. In the mouse model, cotransplantation augmented the EC-accompanied vascularization in the grafts, promoted the maturity of CMs at the infarct area, and improved cardiac function after myocardial infarction. Furthermore, in non-human primates, transplantation of ECs and CMs significantly enhanced graft size and vasculature and improved cardiac function after ischemic reperfusion. CONCLUSIONS: These results demonstrate the synergistic effect of combining iPSC-derived ECs and CMs for therapy in the postmyocardial infarction heart, enabling a promising strategy toward clinical translation.


Assuntos
Células-Tronco Pluripotentes Induzidas , Infarto do Miocárdio , Humanos , Camundongos , Animais , Miócitos Cardíacos/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Células Endoteliais/metabolismo , Camundongos SCID , Camundongos Endogâmicos NOD , Infarto do Miocárdio/patologia , Primatas , Diferenciação Celular , Mamíferos
4.
J Chin Med Assoc ; 85(11): 1038-1043, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36343271

RESUMO

In mid-2022, the COVID-19 cases have reached close to 562 million, but its overall infection rate is hard to confirm. Even with effective vaccines, break-through infections with new variants occur, and safe and reliable testing still plays a critical role in isolation of infected individuals and in control of an outbreak of a COVID-19 pandemic. In response to this urgent need, the diagnostic tests for COVID-19 are rapidly evolving and improving these days. The health authorities of many countries issued requirements for detecting SARS-CoV-2 diagnosis tests during the pandemic and have timely access to these tests to ensure safety and effectiveness. In this study, we compared the requirements of EUA in Taiwan, Singapore, and the United States. For the performance evaluations of nucleic acid extraction, inclusivity, limit of detection (LoD), cross-reactivity, interference, cutoff, and stability, the requirements are similar in the three countries. The use of natural clinical specimens is needed for clinical evaluation in Taiwan and the United States. However, carry-over and cross-contamination studies can be exempted in Taiwan and the United States but are required in Singapore. This review outlines requirements and insight to guide the test developers on the development of IVDs. Considering the rapidly evolving viruses and severe pandemic of COVID-19, timely and accurate diagnostic testing is imperative to the management of diseases. As noted above, the performance requirements for SARS-CoV-2 nucleic acid tests are similar between Taiwan, Singapore and the United States. The differences are mainly in two points: the recommended microorganisms for cross-reactivity study, and the specimen requirement for clinical evaluation. This study provides an overview of current requirements of SARS-CoV-2 nucleic acid tests in Taiwan, Singapore, and the United States.


Assuntos
COVID-19 , Ácidos Nucleicos , Estados Unidos , Humanos , COVID-19/diagnóstico , Pandemias , SARS-CoV-2 , Teste para COVID-19 , Saúde Pública , Taiwan/epidemiologia , Singapura/epidemiologia
5.
Theranostics ; 12(17): 7319-7334, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36438501

RESUMO

Background: The gut microbiota plays a vital role in maintaining tissue homeostasis and regulating disease pathophysiology; however, the underlying mechanisms remain to be elucidated. We previously showed that mice depleted of gut microbiota with antibiotics (ABX mice) were more prone to cardiac rupture after infarction, suggesting that the gut microbiota impacts cardiac structural remodeling following injury. Here, we aimed to determine whether the gut microbiota is required for adaptive cardiac remodeling in response to pressure overload stress. Methods: Transverse aortic constriction (TAC) surgery was performed and cardiac function was evaluated by echocardiography and catheterization, followed by mechanical tests and extracellular matrix (ECM) studies. Germ-free mice with cecal microbiota transplantation were used for validation. 16S ribosomal DNA sequencing and PICRUSt2 analysis were applied to predict the key metabolic pathways. ABX mice were supplemented with the derived metabolic products and their efficacy was tested. To elucidate the underlying mechanism, we isolated mouse primary cardiac fibroblasts and treated them with the metabolites. Lastly, G-coupled protein receptor 41 (GPR41) and GPR43 double knockdown cardiac fibroblasts were generated and the anti-fibrogenic effect of metabolites was determined. Results: Cardiac hypertrophy and dysfunction were more severe in ABX-TAC mice compared to the controls. Moreover, TAC-induced fibrosis was more profound in ABX hearts, which was accompanied by disrupted ECM structure making the heart tissues mechanically weaker and more brittle. Reconstruction of healthy gut microbiota in germ-free mice successfully restored cardiac function and prevented excessive fibrosis and ECM disarray under stress. Furthermore, functional prediction identified acetate and propionate as critical mediators in the gut microbiota-modulated cardiac mechanics. Supplementation of acetate and propionate improved heart function, attenuated fibrosis, and reversed ECM disarray after TAC. In addition, treating primary cardiac fibroblasts with acetate and propionate attenuated cell contraction, inhibited myofibroblast formation, and reduced collagen formation after TGF-ß1 stimulus. Finally, knocking down GPR41 and GPR43 receptors in cardiac fibroblasts blunted the inhibitory effects of acetate and propionate. Conclusions: The gut microbiota is a potential therapeutic target for cardiac ECM remodeling and heart structural integrity. By establishing a healthy gut microbiome or replenishing the derived metabolites, we could improve cardiac health under dysbiosis after pressure-overload stress.


Assuntos
Microbioma Gastrointestinal , Camundongos , Animais , Propionatos/farmacologia , Coração , Fibrose , Acetatos
6.
Cells ; 11(11)2022 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-35681550

RESUMO

The advent of induced pluripotent stem cells (iPSCs) has advanced our understanding of the molecular mechanisms of human disease, drug discovery, and regenerative medicine. As such, the use of iPSCs in drug development and validation has shown a sharp increase in the past 15 years. Furthermore, many labs have been successful in reproducing many disease phenotypes, often difficult or impossible to capture, in commonly used cell lines or animal models. However, there still remain limitations such as the variability between iPSC lines as well as their maturity. Here, we aim to discuss the strategies in generating iPSC-derived cardiomyocytes and neurons for use in disease modeling, drug development and their use in cell therapy.


Assuntos
Células-Tronco Pluripotentes Induzidas , Células-Tronco Pluripotentes , Animais , Terapia Baseada em Transplante de Células e Tecidos , Desenvolvimento de Medicamentos , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Pluripotentes/metabolismo , Medicina Regenerativa
7.
Pharmaceuticals (Basel) ; 15(6)2022 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-35745684

RESUMO

Since December 2019, the novel coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has infected ~435 million people and caused ~6 million related deaths as of March 2022. To combat COVID-19, there have been many attempts to repurpose FDA-approved drugs or revive old drugs. However, many of the current treatment options have been known to cause adverse drug reactions. We employed a population-based drug screening platform using 13 human leukocyte antigen (HLA) homozygous human induced pluripotent cell (iPSC) lines to assess the cardiotoxicity and neurotoxicity of the first line of anti-COVID-19 drugs. We also infected iPSC-derived cells to understand the viral infection of cardiomyocytes and neurons. We found that iPSC-derived cardiomyocytes express the ACE2 receptor which correlated with a higher infection of the SARS-CoV-2 virus (r = 0.86). However, we were unable to detect ACE2 expression in neurons which correlated with a low infection rate. We then assessed the toxicity of anti-COVID-19 drugs and identified two cardiotoxic compounds (remdesivir and arbidol) and four neurotoxic compounds (arbidol, remdesivir, hydroxychloroquine, and chloroquine). These data show that this platform can quickly and easily be employed to further our understanding of cell-specific infection and identify drug toxicity of potential treatment options helping clinicians better decide on treatment options.

8.
Cell Rep ; 39(1): 110643, 2022 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-35385754

RESUMO

In this study, we establish a population-based human induced pluripotent stem cell (hiPSC) drug screening platform for toxicity assessment. After recruiting 1,000 healthy donors and screening for high-frequency human leukocyte antigen (HLA) haplotypes, we identify 13 HLA-homozygous "super donors" to represent the population. These "super donors" are also expected to represent at least 477,611,135 of the global population. By differentiating these representative hiPSCs into cardiomyocytes and neurons we show their utility in a high-throughput toxicity screen. To validate hit compounds, we demonstrate dose-dependent toxicity of the hit compounds and assess functional modulation. We also show reproducible in vivo drug toxicity results using mouse models with select hit compounds. This study shows the feasibility of using a population-based hiPSC drug screening platform to assess cytotoxicity, which can be used as an innovative tool to study inter-population differences in drug toxicity and adverse drug reactions in drug discovery applications.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Células-Tronco Pluripotentes Induzidas , Animais , Cardiotoxicidade , Diferenciação Celular , Células Cultivadas , Humanos , Camundongos , Miócitos Cardíacos , Neurônios
9.
Taiwan J Obstet Gynecol ; 61(2): 270-276, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35361387

RESUMO

OBJECTIVE: We tested the osteoblastic differentiation effects caused by physical stimulation such as hydrostatic pressure using placenta-derived multipotent cells. MATERIALS AND METHODS: The placenta-derived multipotent cells (PDMCs) were treated with osteogenic medium to induce PDMCs differentiation into osteoblast-like cells. The induced PDMCs were stimulated using hydrostatic pressure at a magnitude of 30 kPa for 1 h/day for up to 12 days. The calcium deposition monitored by Alizarin Red staining and the calcium content of each experimental group were quantified. RESULTS: The results demonstrated both the calcium deposition and concentration were elevated through hydrostatic pressure stimulation. Moreover, in order to indicate of PDMC osteodifferentiation, RT-qPCR analysis were performed and mRNA expression of osteoblast differentiation markers (type I collagen, alkaline phosphatase, RUNX2, and BGLAP), the bone morphogenetic protein family (BMP1-7) and BMP receptors (BMPR1A, BMPR1B, and BMPR2) were examined. Among them, the mRNA levels of RUNX2, COL1A1, BMP1, BMP3, and BMPR1A increased significantly in the hydrostatic-pressure-stimulated groups, whereas BGLAP, ALP, BMP2, BMP6, BMPR1B, and BMPR2 exhibited a slight upregulation between the control and experimental groups, indicating the specific signal route induced by hydrostatic pressure on PDMCs. CONCLUSION: Our results revealed the beneficial effects of stem cells stimulated using hydrostatic pressure, which could enhance calcium deposition considerably and facilitate osteodifferentiation, and the results may be applied to tissue regeneration in the near future.


Assuntos
Cálcio , Osteogênese , Feminino , Expressão Gênica , Humanos , Pressão Hidrostática , Osteogênese/genética , Placenta/metabolismo , Gravidez
10.
Stem Cell Rev Rep ; 18(2): 839-852, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35061207

RESUMO

Little is known about genes that induce stem cells differentiation into astrocytes. We previously described that heat shock protein 27 (HSP27) downregulation is directly related to neural differentiation under chemical induction in placenta-derived multipotent stem cells (PDMCs). Using this neural differentiation cell model, we cross-compared transcriptomic and proteomic data and selected 26 candidate genes with the same expression trends in both omics analyses. Those genes were further compared with a transcriptomic database derived from Alzheimer's disease (AD). Eighteen out of 26 candidates showed opposite expression trends between our data and the AD database. The mRNA and protein expression levels of those candidates showed downregulation of HSP27, S100 calcium-binding protein A16 (S100A16) and two other genes in our neural differentiation cell model. Silencing these four genes with various combinations showed that co-silencing HSP27 and S100A16 has stronger effects than other combinations for astrocyte differentiation. The induced astrocyte showed typical astrocytic star-shape and developed with ramified, stringy and filamentous processes as well as differentiated endfoot structures. Also, some of them connected with each other and formed continuous network. Immunofluorescence quantification of various neural markers indicated that HSP27 and S100A16 downregulation mainly drive PDMCs differentiation into astrocytes. Immunofluorescence and confocal microscopic images showed the classical star-like shape morphology and co-expression of crucial astrocyte markers in induced astrocytes, while electrophysiology and Ca2+ influx examination further confirmed their functional characteristics. In conclusion, co-silencing of S100A16 and HSP27 without chemical induction leads to PDMCs differentiation into functional astrocytes.


Assuntos
Astrócitos , Proteínas de Choque Térmico HSP27 , Células-Tronco Multipotentes , Astrócitos/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Proteínas de Ligação ao Cálcio/farmacologia , Feminino , Proteínas de Choque Térmico HSP27/genética , Proteínas de Choque Térmico HSP27/metabolismo , Proteínas de Choque Térmico HSP27/farmacologia , Humanos , Células-Tronco Multipotentes/citologia , Células-Tronco Multipotentes/metabolismo , Placenta/citologia , Placenta/metabolismo , Gravidez , Proteômica , Proteínas S100/genética , Proteínas S100/metabolismo
11.
Diagnostics (Basel) ; 11(12)2021 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-34943506

RESUMO

In bladder cancer, urothelial carcinoma is the most common histologic subtype, accounting for more than 90% of cases. Pathogenic effects due to the dysbiosis of gut microbiota are localized not only in the colon, but also in regulating bladder cancer distally. Butyrate, a short-chain fatty acid produced by gut microbial metabolism, is mainly studied in colon diseases. Therefore, the resolution of the anti-cancer effects of butyrate-producing microbes on bladder urothelial cells and knowledge of the butyrate-responsive molecules must have clinical significance. Here, we demonstrate a correlation between urothelial cancer of the bladder and Butyricicoccus pullicaecorum. This butyrate-producing microbe or their metabolite, butyrate, mediated anti-cancer effects on bladder urothelial cells by regulating cell cycle, cell growth, apoptosis, and gene expression. For example, a tumor suppressor against urothelial cancer of the bladder, bladder cancer-associated protein, was induced in butyrate-treated HT1376 cells, a human urinary bladder cancer cell line. In conclusion, urothelial cancer of the bladder is a significant health problem. To improve the health of bladder urothelial cells, supplementation of B. pullicaecorum may be necessary and can further regulate butyrate-responsive molecular signatures.

12.
Analyst ; 146(24): 7645-7652, 2021 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-34806730

RESUMO

Surface-enhanced Raman scattering (SERS) spectroscopy is a rapid and non-destructive optical detection method that has been applied in various applications. Recently, three-dimensional (3D) substrate-based silicon nanostructures have been widely used as SERS substrates due to their high detection sensitivity, repeatability, and reusability. This paper uses a simple and low-cost electroless etching deposition process to generate silver nanoparticle-decorated porous silicon (Ag-PS) substrates. We propose a contact deposition process to generate localized Ag-PS (LocAg-PS) for SERS analysis. Due to the hydrophilic LocAg-PS pad on the hydrophobic PS background, the sample droplets self-aligned to the predefined LocAg-PS pads and condensed into a higher local concentration for high sensitivity SERS detection without extensive search for the hot spot. The effects of critical fabrication parameters and SERS analysis on the LocAg-PS surface were evaluated.

13.
Polymers (Basel) ; 13(11)2021 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-34073347

RESUMO

Composite electrospun fibers were fabricated to develop drug loaded scaffolds to promote bone tissue regeneration. Multi-wall carbon nanotubes (MWCNTs) were incorporated to polylactic acid (PLA) to strengthen electrospun nanofibers. To modulate drug release behavior, different ratios of hydrophilic polyethylene glycol (PEG) were added to composite fibers. Glass transition temperature (Tg) can be reduced by the incorporated PEG to enhance the ductility of the nanofibers. The SEM images and the MTT results demonstrated that composite fibers are suitable scaffolds for cell adhesion and proliferation. Dexamethasone (DEX), an osteogenic inducer, was loaded to PLA/MWCNT/PEG fibers. The surface element analysis performed by XPS showed that fluorine of DEX in pristine PLA fibers was much higher than those of the MWCNT-containing fibers, suggesting that the pristine PLA fibers mainly load DEX on their surfaces, whereas MWCNTs can adsorb DEX with evenly distribution in nanofibers. Drug release experiments demonstrated that the release profiles of DEX were manipulated by the ratio of PEG, and that the more PEG in the nanofibers, the faster DEX was released. When rat bone marrow stromal cells (rBMSCs) were seeded on these nanofibers, the Alizarin Red S staining and calcium quantification results demonstrated that loaded DEX were released to promote osteogenic differentiation of rBMSCs and facilitate mineralized tissue formation. These results indicated that the DEX-loaded PLA/MWCNT/PEG nanofibers not only enhanced mechanical strength, but also promoted osteogenesis of stem cells via the continuous release of DEX. The nanofibers should be a potential scaffold for bone tissue engineering application.

14.
Methods Mol Biol ; 2267: 1-6, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33786781

RESUMO

Many proteins involved in the DNA damage pathway shuttle between the cytoplasm and nucleus, and their localizations are important for functions. In that regard, immunofluorescence microscopy has been widely used to delineate the temporal and spatial regulation of proteins. Here, we describe an unconventional method for studying the cellular localization of CHK1, a cell cycle checkpoint kinase that undergoes shuttling from the cytoplasm to the nucleus in response to genotoxic stress. In this study, we included an acid extraction step to better reveal the nuclear localization of CHK1.


Assuntos
Quinase 1 do Ponto de Checagem/metabolismo , Imunofluorescência/métodos , Células HCT116 , Humanos , Microscopia Confocal/métodos , Transporte Proteico
15.
Cell Death Dis ; 11(12): 1046, 2020 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-33311481

RESUMO

B-cell translocation gene 3 (BTG3) is a member of the antiproliferative BTG gene family and is a downstream target of p53. Here, we show that senescence triggered by BTG3 depletion was accompanied by a secretome enriched with cytokines, growth factors, and matrix-remodeling enzymes, which could promote angiogenesis and cell scattering in vitro. We present evidence that at least part of these activities can be explained by elevated HIF-1α activity. Mechanistically, the BTG3 C-terminal domain competes with the coactivator p300 for binding the HIF-1α transactivation domain. The angiogenic promoting effect of BTG3 knockdown was largely diminished upon co-depletion of HIF-1α, indicating that HIF-1α is a major downstream target of BTG3 in the control of angiogenesis. In vivo, ectopic expression of BTG3 suppresses angiogenesis in xenograft tumors; and syngenic tumor growth and metastasis were enhanced in Btg3-null mice. Moreover, analysis of clinical datasets revealed that a higher BTG3/VEGFA expression ratio correlates with improved patient survival in a number of cancer types. Taken together, our findings highlight the non-autonomous regulation of tumor microenvironment by BTG3 while suppressing tumor progression.


Assuntos
Proteínas de Ciclo Celular/deficiência , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Microambiente Tumoral , Proteínas Supressoras de Tumor/deficiência , Animais , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular , Proliferação de Células/genética , Senescência Celular , Fibroblastos/metabolismo , Deleção de Genes , Regulação Neoplásica da Expressão Gênica , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Camundongos , Neoplasias/irrigação sanguínea , Neoplasias/genética , Neoplasias/patologia , Neovascularização Fisiológica , Ligação Proteica , Análise de Sobrevida , Microambiente Tumoral/genética , Proteínas Supressoras de Tumor/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
16.
Aging (Albany NY) ; 12(22): 22700-22718, 2020 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-33196458

RESUMO

Malignant cancer may contain highly heterogeneous populations of cells, including stem-like cells which were resistant to chemotherapy agents, radiation, mechanical stress, and immune surveillance. The characterization of these specific subpopulations might be critical to develop novel strategy to remove malignant tumors. We selected and enriched small population of human melanoma A2058 cells by repetitive selection cycles (selection, restoration, and amplification). These subpopulation of melanoma cells persisted the characteristics of slower cell proliferation, enhanced drug-resistance, elevated percentage of side population as analyzed by Hoechst33342 exclusion, in vitro sphere formation, and in vivo xenograft tumor formation by small amount of tumor cells. The selected populations would be melanoma stem-like cells with high expression of stem cell markers and altered kinase activation. Microarray and bioinformatics analysis highlighted the high expression of angiopoietin-like 4 protein in drug-selected melanoma stem-like cells. Further validation by specific shRNA demonstrated the role of angiopoietin-like 4 protein in drug-selected subpopulation associated with enhanced drug-resistance, sphere formation, reduced kinase activation, in vitro tube-forming ability correlated with heparan-sulfate proteoglycans. Our finding would be applicable to explore the mechanism of melanoma stemness and use angiopoietin-like 4 as potential biomarkers to identify melanoma stem-like cells.


Assuntos
Proteína 4 Semelhante a Angiopoietina/metabolismo , Resistencia a Medicamentos Antineoplásicos , Proteoglicanas de Heparan Sulfato/metabolismo , Melanoma/metabolismo , Células-Tronco Neoplásicas/metabolismo , Neovascularização Patológica/metabolismo , Linhagem Celular Tumoral , Humanos , Melanoma/patologia , Células-Tronco Neoplásicas/patologia , Ligação Proteica
17.
J Biomed Sci ; 27(1): 92, 2020 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-32887585

RESUMO

BACKGROUND: The Taiwan Human Disease iPSC Service Consortium was established to accelerate Taiwan's growing stem cell research initiatives and provide a platform for researchers interested in utilizing induced pluripotent stem cell (iPSC) technology. The consortium has generated and characterized 83 iPSC lines: 11 normal and 72 disease iPSC lines covering 21 different diseases, several of which are of high incidence in Taiwan. Whether there are any reprogramming-induced recurrent copy number variant (CNV) hotspots in iPSCs is still largely unknown. METHODS: We performed genome-wide copy number variant screening of 83 Han Taiwanese iPSC lines and compared them with 1093 control subjects using an Affymetrix genome-wide human SNP array. RESULTS: In the iPSCs, we identified ten specific CNV loci and seven "polymorphic" CNV regions that are associated with the reprogramming process. Additionally, we established several differentiation protocols for our iPSC lines. We demonstrated that our iPSC-derived cardiomyocytes respond to pharmacological agents and were successfully engrafted into the mouse myocardium demonstrating their potential application in cell therapy. CONCLUSIONS: The CNV hotspots induced by cell reprogramming have successfully been identified in the current study. This finding may be used as a reference index for evaluating iPSC quality for future clinical applications. Our aim was to establish a national iPSC resource center generating iPSCs, made available to researchers, to benefit the stem cell community in Taiwan and throughout the world.


Assuntos
Diferenciação Celular , Variações do Número de Cópias de DNA , Células-Tronco Pluripotentes Induzidas/metabolismo , Miócitos Cardíacos/fisiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Reprogramação Celular , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Taiwan , Adulto Jovem
18.
Aging (Albany NY) ; 12(17): 16803-16819, 2020 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-32756007

RESUMO

The detachment of tumor cells from extracellular matrix and survival under anchorage-independence were recognized as the initial step of tumor metastasis. Previously we had demonstrated that anchorage-independence altered gene expressions and showed characteristics of cell invasiveness loss, enhanced chemosensitivity, and enhanced subcutaneous tumor formation. However, whether it affected histological phenotypes in tumor tissues remained unclear. Melanoma metastases were generated in nude mice using adherent or suspended melanoma cells. Examination of melanoma metastases revealed histological features of extensive vascular structures in adherent cell-derived tumors, while not seen in suspended cell-derived tumors. Quantitative proteomic analysis at adherent, suspended, and re-attached melanoma cells suggested that aminopeptidase N was potentially downregulated upon cell suspension or reattachment. Downregulation of aminopeptidase N by gene-specific shRNAs showed reduced cell invasiveness and enhanced subcutaneous tumor formation that was consistent with previous observations. Experiments by suppression or overexpression of aminopeptidase N expression demonstrated that aminopeptidase N regulated syndecan-1 and integrin ß4 expression through PKCδ pathway. Histological analysis at melanoma metastases further suggested that CD31+/aminopeptidase N+/syndecan-1+/integrin ß4+ phenotypes were associated with vascular structures. In summary, we suggested the expression axis of aminopeptidase N/syndecan-1/integrin ß4 in melanoma cells was suppressed by detachment stress, which diminished vascular phenotypes of melanoma metastases.

19.
Oncol Lett ; 19(4): 3021-3026, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32218859

RESUMO

Thyroid cancer is the most commonly diagnosed endocrine cancer. Anaplastic thyroid cancer (ATC) is the most aggressive type of thyroid cancer and has a poor prognosis. Loss of p53 function has been reported to lead to poorly differentiated thyroid tumors; therefore, mutant p53 protein can be considered a crucial therapeutic target in patients with ATC. Sorafenib, a multi-kinase inhibitor, has been approved for the treatment of metastatic and differentiated thyroid cancer. Combined targeted therapy, including sorafenib, may be clinically significant for patients with ATC harboring p53 mutations. In the present study, CP-31398, a p53-restoring agent, was used to improve the therapeutic efficacy of sorafenib in SW579 cells, an ATC cell line harboring p53 mutations. The molecular function of CP-31398 was evaluated using western blot analysis and a luciferase reporter assay. The decreased viability of SW579 cells, following CP-31398 treatment, was augmented by sorafenib, and CP-31398 enhanced the antimitogenic effect of sorafenib; thus, sorafenib and CP-31398 synergistically inhibited the growth of SW579 cells. These results indicate a potential clinical application of CP-31398 for patients with ATC harboring p53 abnormalities, since these individuals generally respond poorly to sorafenib alone.

20.
Stem Cell Res ; 44: 101734, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32151952

RESUMO

A hexanucleotide repeat expansion in chromosome 9 open reading frame 72 (C9orf72) gene causes a heterogeneous neurodegenerative disorder that includes amyotrophic lateral sclerosis (ALS), frontotemporal degeneration (FTD), and parkinsonism. Here, we used the Sendai virus delivery system to generate induced pluripotent stem cells (iPSCs) from peripheral blood mononuclear cells of a male patient with an increased hexanucleotide repeat expansion in C9orf72. The resulting iPSCs exhibited pluripotency, confirmed by immunofluorescent staining for pluripotency markers, and differentiated into three germ layers in vivo. This cellular model will provide a useful platform for further pathophysiological studies of C9orf72-related neurodegeneration.


Assuntos
Esclerose Lateral Amiotrófica , Linhagem Celular , Demência Frontotemporal , Células-Tronco Pluripotentes Induzidas , Transtornos Parkinsonianos , Esclerose Lateral Amiotrófica/genética , Proteína C9orf72/genética , Expansão das Repetições de DNA/genética , Demência Frontotemporal/genética , Humanos , Leucócitos Mononucleares , Masculino , Mutação
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