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1.
Cell Death Dis ; 14(11): 754, 2023 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-37980334

RESUMO

Glioma, the most common primary malignant tumor of the central nervous system, lacks effective targeted therapies. This study investigates the role of SOAT1, a key gene involved in cholesterol esterification, in glioma prognosis and its association with ferroptosis. Although the impact of SOAT1 on glioma prognosis has been recognized, its precise mechanism remains unclear. In this study, we demonstrate that inhibiting SOAT1 increases the sensitivity of glioma cells to ferroptosis, both in vitro and in vivo. Mechanistically, SOAT1 positively modulates the expression of SLC40A1, an iron transporter, resulting in enhanced intracellular iron outflow, reduced intracellular iron levels, and subsequent disruption of ferroptosis. Importantly, we find that SOAT1 regulates ferroptosis independently of SREBPs, which are known to be involved in ferroptosis regulation. Furthermore, we identify the involvement of the PI3K-AKT-mTOR signaling pathway in mediating the regulatory effects of SOAT1 on SLC40A1 expression and ferroptosis sensitivity. These findings highlight the contribution of intracellular signaling cascades in the modulation of ferroptosis by SOAT1. We show that inhibiting SOAT1 enhances the efficacy of radiotherapy in gliomas, both in vitro and in vivo, by promoting sensitivity to ferroptosis. This suggests that targeting SOAT1 could potentially improve therapeutic outcomes for glioma patients. In summary, this study uncovers the pivotal role of SOAT1 as a link between cholesterol esterification and ferroptosis in glioma. Our findings underscore the potential of SOAT1 as a promising clinical therapeutic target, providing new avenues for the development of effective treatments for glioma. Further research is warranted to unravel the complete regulatory mechanisms of SOAT1 and explore its clinical applications.


Assuntos
Ferroptose , Glioma , Humanos , Ferroptose/genética , Fosfatidilinositol 3-Quinases , Glioma/metabolismo , Colesterol/metabolismo , Ferro/farmacologia
2.
Oncoimmunology ; 12(1): 2265703, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37808405

RESUMO

Chimeric antigen receptor (CAR) T cell immunotherapy has demonstrated success in the treatment of hematological malignancies; however, its efficacy and applications in solid tumors remain limited. Immunosuppressive factors, particularly inhibitory checkpoint molecules, restrict CAR T cell activity inside solid tumors. The modulation of checkpoint pathways has emerged as a promising approach to promote anti-tumor responses in CAR T cells. Programmed cell death protein 1 (PD1) and T cell immunoreceptor with Ig and ITIM domains (TIGIT) are two critical immune-checkpoint molecules that suppress anti-tumor activity in T cells. Simultaneous targeting of these two inhibitory molecules could be an efficient checkpoint modulation strategy. Here, we developed a PD1-TIGIT chimeric immune-checkpoint switch receptor (CISR) that enhances the efficacy of CAR T cell immunotherapy by reversing the inhibitory checkpoint signals of PD1/PDL1 and/or TIGIT/CD155. In addition to neutralizing PDL1 and CD155, this chimeric receptor is engineered with the transmembrane region and intracellular domain of CD28, thereby effectively enhancing T cell survival and tumor-targeting functions. Notably, under simultaneous stimulation of PDL1 and CD155, CISR-CAR T cells demonstrate superior performance in terms of cell survival, proliferation, cytokine release, and cytotoxicity in vitro, compared with conventional CAR T cells. Experiments utilizing both cell line- and patient-derived xenotransplantation tumor models showed that CISR-CAR T cells exhibit robust infiltration and anti-tumor efficiency in vivo. Our results highlight the potential for the CISR strategy to enhance T cell anti-tumor efficacy and provide an alternative approach for T cell-based immunotherapies.


Assuntos
Neoplasias Hematológicas , Neoplasias , Humanos , Linfócitos T , Receptor de Morte Celular Programada 1 , Neoplasias/terapia , Imunoterapia , Neoplasias Hematológicas/metabolismo , Receptores Imunológicos/metabolismo
3.
Cell Stem Cell ; 30(9): 1130-1147, 2023 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-37625410

RESUMO

Chemical reprogramming offers an unprecedented opportunity to control somatic cell fate and generate desired cell types including pluripotent stem cells for applications in biomedicine in a precise, flexible, and controllable manner. Recent success in the chemical reprogramming of human somatic cells by activating a regeneration-like program provides an alternative way of producing stem cells for clinical translation. Likewise, chemical manipulation enables the capture of multiple (stem) cell states, ranging from totipotency to the stabilization of somatic fates in vitro. Here, we review progress in using chemical approaches for cell fate manipulation in addition to future opportunities in this promising field.


Assuntos
Células-Tronco Pluripotentes , Humanos , Diferenciação Celular
4.
Cell Rep ; 42(6): 112547, 2023 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-37224020

RESUMO

Human somatic cells can be reprogrammed to pluripotent stem cells by small molecules through an intermediate stage with a regeneration signature, but how this regeneration state is induced remains largely unknown. Here, through integrated single-cell analysis of transcriptome, we demonstrate that the pathway of human chemical reprogramming with regeneration state is distinct from that of transcription-factor-mediated reprogramming. Time-course construction of chromatin landscapes unveils hierarchical histone modification remodeling underlying the regeneration program, which involved sequential enhancer recommissioning and mirrored the reversal process of regeneration potential lost in organisms as they mature. In addition, LEF1 is identified as a key upstream regulator for regeneration gene program activation. Furthermore, we reveal that regeneration program activation requires sequential enhancer silencing of somatic and proinflammatory programs. Altogether, chemical reprogramming resets the epigenome through reversal of the loss of natural regeneration, representing a distinct concept for cellular reprogramming and advancing the development of regenerative therapeutic strategies.


Assuntos
Células-Tronco Pluripotentes Induzidas , Células-Tronco Pluripotentes , Humanos , Epigenoma , Epigênese Genética , Reprogramação Celular/genética , Células-Tronco Pluripotentes/metabolismo , Fatores de Transcrição/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo
5.
Immunol Rev ; 315(1): 154-170, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36939073

RESUMO

Lymphoid cells encompass the adaptive immune system, including T and B cells and Natural killer T cells (NKT), and innate immune cells (ILCs), including Natural Killer (NK) cells. During adult life, these lineages are thought to derive from the differentiation of long-term hematopoietic stem cells (HSCs) residing in the bone marrow. However, during embryogenesis and fetal development, the ontogeny of lymphoid cells is both complex and multifaceted, with a large body of evidence suggesting that lymphoid lineages arise from progenitor cell populations antedating the emergence of HSCs. Recently, the application of single cell RNA-sequencing technologies and pluripotent stem cell-based developmental models has provided new insights into lymphoid ontogeny during embryogenesis. Indeed, PSC differentiation platforms have enabled de novo generation of lymphoid immune cells independently of HSCs, supporting conclusions drawn from the study of hematopoiesis in vivo. Here, we examine lymphoid development from non-HSC progenitor cells and technological advances in the differentiation of human lymphoid cells from pluripotent stem cells for clinical translation.


Assuntos
Células-Tronco Pluripotentes , Adulto , Humanos , Diferenciação Celular , Células-Tronco Hematopoéticas , Células Matadoras Naturais , Hematopoese
6.
Cell Stem Cell ; 30(4): 450-459.e9, 2023 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-36944335

RESUMO

We recently demonstrated the chemical reprogramming of human somatic cells to pluripotent stem cells (hCiPSCs), which provides a robust approach for cell fate manipulation. However, the utility of this chemical approach is currently hampered by slow kinetics. Here, by screening for small molecule boosters and systematically optimizing the original condition, we have established a robust, chemically defined reprogramming protocol, which greatly shortens the induction time from ∼50 days to a minimum of 16 days and enables highly reproducible and efficient generation of hCiPSCs from all 17 tested donors. We found that this optimized protocol enabled a more direct reprogramming process by promoting cell proliferation and oxidative phosphorylation metabolic activities at the early stage. Our results highlight a distinct chemical reprogramming pathway that leads to a shortcut for the generation of human pluripotent stem cells, which represents a powerful strategy for human cell fate manipulation.


Assuntos
Células-Tronco Pluripotentes Induzidas , Células-Tronco Pluripotentes , Humanos , Reprogramação Celular , Células-Tronco Pluripotentes Induzidas/metabolismo , Diferenciação Celular , Proliferação de Células
7.
Nat Metab ; 5(1): 29-40, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36624157

RESUMO

Human pluripotent stem cell-derived islets (hPSC islets) are a promising alternative to primary human islets for the treatment of insulin-deficient diabetes. We previously demonstrated the feasibility of this approach in nonhuman primates; however, the therapeutic effects of hPSC islets can be limited by the maladaptive processes at the transplantation site. Here, we demonstrate successful implantation of hPSC-derived islets in a new transplantation site in the abdomen, the subanterior rectus sheath, in eight nonhuman primates (five male and three female). In this proof-of-principle study, we find that hPSC islets survive and gradually mature after transplantation, leading to improved glycemic control in diabetic primates. Notably, C-peptide secretion responds to meal challenge from 6 weeks post-transplantation (wpt), with stimulation indices comparable to those of native islets. The average post-prandial C-peptide level reaches approximately 2.0 ng ml-1 from 8 wpt, which is five times higher than the peak value we previously obtained after portal vein infusion of hPSC islets and was associated with a decrease of glycated hemoglobin levels by 44% at 12 wpt. Although additional studies in larger cohorts involving long-term follow-up of transplants are needed, our results indicate that the subanterior rectus sheath supports functional maturation and maintenance of hPSC islets, suggesting that it warrants further exploration as a transplantation target site in the context of for hPSC-based cell-replacement therapies.


Assuntos
Transplante das Ilhotas Pancreáticas , Ilhotas Pancreáticas , Animais , Masculino , Humanos , Feminino , Transplante das Ilhotas Pancreáticas/métodos , Peptídeo C , Primatas , Abdome
8.
Oxid Med Cell Longev ; 2022: 7862430, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36439690

RESUMO

Glioma is the most common primary brain tumor, with a high rate of recurrence and treatment resistance. Glioblastoma is highly invasive, infiltrating surrounding brain parenchyma, and is known to cause intracranial metastasis resulting in a dismal prognosis. Hypoxia contributes significantly to chemo- and radiotherapy resistance in cancer. Ferroptosis is a nonapoptotic oxidative cell death that has been identified as a potential anticancer mechanism. Sulfasalazine (SAS) activates ferroptosis and plays a potential role in tumor treatment. However, the relationship between hypoxia and SAS resistance has not been elucidated. This study is aimed at investigating the role of hypoxia in SAS-induced ferroptosis and the underlying mechanisms. Here, we found that hypoxia significantly suppressed SAS-induced ferroptosis by upregulating SLC7A11 expression in the U87 and U251 glioma cell lines. Hypoxia promotes SLC7A11 expression by enhancing the PI3K/AKT/HIF-1α pathway. The AKT inhibitor MK-2206 and HIF-1α inhibitor PX-478 significantly reversed this effect. In addition, under normoxia, PX-478 induced a higher lipid peroxidation level by decreasing SLC7A11 expression in the U87 and U251 cells but could not induce cell death directly; it could significantly enhance the tumor cell killing effect of SAS. In vivo, the combination of PX-478 and SAS had a coordinated synergistic effect on anticancer activity, as revealed by subcutaneous and orthotopic xenograft mouse models. In conclusion, hypoxia enhanced glioma resistance to SAS-induced ferroptosis by upregulating SLC7A11 via activating the PI3K/AKT/HIF-1α axis. Combination therapy with PX-478 and SAS may be a potential strategy against glioma.


Assuntos
Ferroptose , Glioma , Humanos , Animais , Camundongos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Sulfassalazina/farmacologia , Sulfassalazina/uso terapêutico , Transdução de Sinais , Glioma/metabolismo , Hipóxia/metabolismo , Sistema y+ de Transporte de Aminoácidos/metabolismo
9.
Stem Cell Reports ; 17(9): 2156-2166, 2022 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-35985333

RESUMO

Human macrophages are a natural host of many mycobacterium species, including Mycobacterium abscessus (M. abscessus), an emerging pathogen affecting immunocompromised and cystic fibrosis patients with few available treatments. The search for an effective treatment is hindered by the lack of a tractable in vitro intracellular infection model. Here, we established a reliable model for M. abscessus infection using human pluripotent stem cell-derived macrophages (hPSC-macrophages). hPSC differentiation permitted reproducible generation of functional macrophages that were highly susceptible to M. abscessus infection. Electron microscopy demonstrated that M. abscessus was present in the hPSC-macrophage vacuoles. RNA sequencing analysis revealed a time-dependent host cell response, with differing gene and protein expression patterns post-infection. Engineered tdTOMATO-expressing hPSC-macrophages with GFP-expressing mycobacteria enabled rapid image-based high-throughput analysis of intracellular infection and quantitative assessment of antibiotic efficacy. Our study describes the first to our knowledge hPSC-based model for M. abscessus infection, representing a novel and accessible system for studying pathogen-host interaction and drug discovery.


Assuntos
Infecções por Mycobacterium não Tuberculosas , Mycobacterium abscessus , Mycobacterium , Células-Tronco Pluripotentes , Humanos , Macrófagos/metabolismo , Infecções por Mycobacterium não Tuberculosas/metabolismo , Infecções por Mycobacterium não Tuberculosas/microbiologia
10.
Korean J Radiol ; 23(8): 821-827, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35695314

RESUMO

OBJECTIVE: To determine the anatomical characteristics of the petrous ridge and trigeminal nerve in trigeminal neuralgia (TN) without neurovascular compression (NVC). MATERIALS AND METHODS: From May 2017 to March 2021, 66 patients (49 female and 17 male; mean age ± standard deviation [SD], 56.8 ± 13.3 years) with TN without NVC and 57 controls (46 female and 11 male; 52.0 ± 15.6 years) were enrolled. The angle of the petrous ridge (APR) and angle of the trigeminal nerve (ATN) were measured using magnetic resonance imaging with a high-resolution three-dimensional T2 sequence. Data on the symptomatic side were compared with those on the asymptomatic side in patients and with the mean measurements of the bilateral sides in controls. Receiver operating characteristic (ROC) analysis was conducted to evaluate the performance of APR and ATN in distinguishing TN patients from controls. RESULTS: In TN patients without NVC, the mean ± standard deviation (SD) of APR on the symptomatic side (98.40° ± 19.75°) was significantly smaller than that of the asymptomatic side (105.59° ± 22.45°, p = 0.019) and controls (108.44° ± 15.98°, p = 0.003). The mean ATN ± SD on the symptomatic side (144.41° ± 8.92°) was significantly smaller than that of the asymptomatic side (149.67° ± 8.09°, p = 0.003) and controls (150.45° ± 8.48°, p = 0.001). The area under the ROC curve for distinguishing TN patients from controls was 0.673 (95% confidence interval [CI]: 0.579-0.758) for APR and 0.700 (CI: 0.607-0.782) for ATN. The sensitivity and specificity using the diagnostic cutoff yielding the highest Youden index were 81.8% (54/66) and 49.1% (28/57), respectively, for APR (with a cutoff score of 94.30°) and 65.2% (43/66) and 66.7% (38/57), respectively, for ATN (cutoff score, 148.25°). CONCLUSION: In patients with TN without NVC, APR and ATN were smaller than those in controls, which may explain the potential cause of TN and provide additional information for diagnosis.


Assuntos
Neuralgia do Trigêmeo , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Nervo Trigêmeo/diagnóstico por imagem , Nervo Trigêmeo/patologia , Neuralgia do Trigêmeo/diagnóstico por imagem , Neuralgia do Trigêmeo/etiologia
11.
Sensors (Basel) ; 22(9)2022 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-35590933

RESUMO

Ship recognition is a fundamental and essential step in maritime activities, and it can be widely used in maritime rescue, vessel management, and other applications. However, most studies conducted in this area use synthetic aperture radar (SAR) images and space-borne optical images, and those studies utilizing visible images are limited to the coarse-grained level. In this study, we constructed a fine-grained ship dataset with real images and simulation images that consisted of five categories of ships. To solve the problem of low accuracy in fine-grained ship classification with different angles in visible images, a network based on domain adaptation and a transformer was proposed. Concretely, style transfer was first used to reduce the gap between the simulation images and real images. Then, with the goal of utilizing the simulation images to execute classification tasks on the real images, a domain adaptation network based on local maximum mean discrepancy (LMMD) was used to align the different domain distributions. Furthermore, considering the innate attention mechanism of the transformer, a vision transformer (ViT) was chosen as the feature extraction module to extract the fine-grained features, and a fully connected layer was used as the classifier. Finally, the experimental results showed that our network had good performance on the fine-grained ship dataset with an overall accuracy rate of 96.0%, and the mean average precision (mAP) of detecting first and then classifying with our network was 87.5%, which also verified the feasibility of using images generated by computer simulation technology for auxiliary training.


Assuntos
Radar , Navios , Simulação por Computador , Tecnologia
12.
Appl Spectrosc ; 76(9): 1068-1079, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35583031

RESUMO

In order to extract useful information from X-ray fluorescence (XRF) spectra and establish a high-accuracy prediction model of soil heavy metal contents, a hybrid model combining a deep belief network (DBN) with a tree-based model was proposed. The DBN was first introduced into feature extraction of XRF spectral data, which can obtain deep layer features of spectra. Owing to the strong regression ability of the tree-based model, it can offset the deficiency of DBN in prediction ability so it was used for predicting heavy metal contents based on the extracted features. In order to further improve the performance of the model, the parameters of model can be optimized according to the prediction error, which was completed by sparrow search algorithm and the gird search. The hybrid model was applied to predict the contents of As and Pb based on spectral data of overlapping peaks. It can be obtained that R2 of As and Pb reached 0.9884 and 0.9358, the mean square error of As and Pb are as low as 0.0011 and 0.0058, which outperform other commonly used models. That proved the combination of DBN and tree-based model can obtain more accurate prediction results.


Assuntos
Metais Pesados , Solo , Algoritmos , Chumbo
13.
Front Immunol ; 13: 846281, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35371075

RESUMO

Thymic epithelium is critical for the structural integrity of the thymus and for T cell development. Within the fully formed thymus, large numbers of hematopoietic cells shape the thymic epithelium into a scaffold-like structure which bears little similarity to classical epithelial layers, such as those observed in the skin, intestine or pancreas. Here, we show that human thymic epithelial cells (TECs) possess an epithelial identity that also incorporates the expression of mesenchymal cell associated genes, whose expression levels vary between medullary and cortical TECs (m/cTECs). Using pluripotent stem cell (PSC) differentiation systems, we identified a unique population of cells that co-expressed the master TEC transcription factor FOXN1, as well as the epithelial associated marker EPCAM and the mesenchymal associated gene CD90. Using the same serum free culture conditions, we also observed co-expression of EPCAM and CD90 on cultured TECs derived from neonatal human thymus in vitro. Single cell RNA-sequencing revealed these cultured TECs possessed an immature mTEC phenotype and expressed epithelial and mesenchymal associated genes, such as EPCAM, CLDN4, CD90 and COL1A1. Importantly, flow cytometry and single cell RNA-sequencing analysis further confirmed the presence of an EPCAM+CD90+ population in the CD45- fraction of neonatal human thymic stromal cells in vivo. Using the human thymus cell atlas, we found that cTECs displayed more pronounced mesenchymal characteristics than mTECs during embryonic development. Collectively, these results suggest human TECs possess a hybrid gene expression program comprising both epithelial and mesenchymal elements, and provide a basis for the further exploration of thymus development from primary tissues and from the in vitro differentiation of PSCs.


Assuntos
Células Epiteliais , RNA , Diferenciação Celular , Molécula de Adesão da Célula Epitelial/genética , Células Epiteliais/metabolismo , Epitélio , Humanos , RNA/metabolismo , Antígenos Thy-1/metabolismo , Timo
14.
Nature ; 605(7909): 325-331, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35418683

RESUMO

Cellular reprogramming can manipulate the identity of cells to generate the desired cell types1-3. The use of cell intrinsic components, including oocyte cytoplasm and transcription factors, can enforce somatic cell reprogramming to pluripotent stem cells4-7. By contrast, chemical stimulation by exposure to small molecules offers an alternative approach that can manipulate cell fate in a simple and highly controllable manner8-10. However, human somatic cells are refractory to chemical stimulation owing to their stable epigenome2,11,12 and reduced plasticity13,14; it is therefore challenging to induce human pluripotent stem cells by chemical reprogramming. Here we demonstrate, by creating an intermediate plastic state, the chemical reprogramming of human somatic cells to human chemically induced pluripotent stem cells that exhibit key features of embryonic stem cells. The whole chemical reprogramming trajectory analysis delineated the induction of the intermediate plastic state at the early stage, during which chemical-induced dedifferentiation occurred, and this process was similar to the dedifferentiation process that occurs in axolotl limb regeneration. Moreover, we identified the JNK pathway as a major barrier to chemical reprogramming, the inhibition of which was indispensable for inducing cell plasticity and a regeneration-like program by suppressing pro-inflammatory pathways. Our chemical approach provides a platform for the generation and application of human pluripotent stem cells in biomedicine. This study lays foundations for developing regenerative therapeutic strategies that use well-defined chemicals to change cell fates in humans.


Assuntos
Diferenciação Celular , Reprogramação Celular , Células-Tronco Pluripotentes Induzidas , Linhagem da Célula , Humanos , Células-Tronco Pluripotentes Induzidas/citologia
15.
Nat Med ; 28(2): 272-282, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35115708

RESUMO

Human pluripotent stem-cell-derived islets (hPSC-islets) are a promising cell resource for diabetes treatment1,2. However, this therapeutic strategy has not been systematically assessed in large animal models physiologically similar to humans, such as non-human primates3. In this study, we generated islets from human chemically induced pluripotent stem cells (hCiPSC-islets) and show that a one-dose intraportal infusion of hCiPSC-islets into diabetic non-human primates effectively restored endogenous insulin secretion and improved glycemic control. Fasting and average pre-prandial blood glucose levels significantly decreased in all recipients, accompanied by meal or glucose-responsive C-peptide release and overall increase in body weight. Notably, in the four long-term follow-up macaques, average hemoglobin A1c dropped by over 2% compared with peak values, whereas the average exogenous insulin requirement reduced by 49% 15 weeks after transplantation. Collectively, our findings show the feasibility of hPSC-islets for diabetic treatment in a preclinical context, marking a substantial step forward in clinical translation of hPSC-islets.


Assuntos
Diabetes Mellitus Experimental , Transplante das Ilhotas Pancreáticas , Ilhotas Pancreáticas , Animais , Glicemia , Diabetes Mellitus Experimental/terapia , Humanos , Insulina , Transplante das Ilhotas Pancreáticas/fisiologia , Primatas
16.
Cell Death Dis ; 13(1): 73, 2022 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-35064112

RESUMO

Ferroptosis is a form of cell death characterized by lipid peroxidation. Previous studies have reported that knockout of NF-κB activating protein (NKAP), an RNA-binding protein, increased lipid peroxidation level in naive T cells and induced cell death in colon cancer cells. However, there was no literature reported the relationship between NKAP and ferroptosis in glioblastoma cells. Notably, the mechanism of NKAP modulating ferroptosis is still unknown. Here, we found NKAP knockdown induced cell death in glioblastoma cells. Silencing NKAP increased the cell sensitivity to ferroptosis inducers both in vitro and in vivo. Exogenous overexpression of NKAP promoted cell resistance to ferroptosis inducers by positively regulating a ferroptosis defense protein, namely cystine/glutamate antiporter (SLC7A11). The regulation of SLC7A11 by NKAP can be weakened by the m6A methylation inhibitor cycloleucine and knockdown of the m6A writer METTL3. NKAP combined the "RGAC" motif which was exactly in line with the m6A motif "RGACH" (R = A/G, H = A/U/C) uncovered by the m6A-sequence. RNA Immunoprecipitation (RIP) and Co-Immunoprecipitation (Co-IP) proved the interaction between NKAP and m6A on SLC7A11 transcript. Following its binding to m6A, NKAP recruited the splicing factor proline and glutamine-rich (SFPQ) to recognize the splice site and then conducted transcription termination site (TTS) splicing event on SLC7A11 transcript and the retention of the last exon, screened by RNA-sequence and Mass Spectrometry (MS). In conclusion, NKAP acted as a new ferroptosis suppressor by binding to m6A and then promoting SLC7A11 mRNA splicing and maturation.


Assuntos
Sistema y+ de Transporte de Aminoácidos , Ferroptose , Glioblastoma , Splicing de RNA , Proteínas Repressoras , Sistema y+ de Transporte de Aminoácidos/metabolismo , Ferroptose/genética , Glioblastoma/genética , Humanos , Metiltransferases/metabolismo , NF-kappa B/metabolismo , RNA Mensageiro , Proteínas de Ligação a RNA , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo
17.
BMC Cancer ; 21(1): 1181, 2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34740322

RESUMO

BACKGROUND: Increased expression of the transcription factor Forkhead box M1 (FOXM1) has been reported to play an important role in the progression and development of multiple tumors, but the molecular mechanisms that regulate FOXM1 expression remain unknown, and the role of FOXM1 in aerobic glycolysis is still not clear. METHODS: The expression of FOXM1 and NADPH oxidase 4 (NOX4) in normal brain tissues and glioma was detected in data from the TCGA database and in our specimens. The effect of NOX4 on the expression of FOXM1 was determined by Western blot, qPCR, reactive oxygen species (ROS) production assays, and luciferase assays. The functions of NOX4 and FOXM1 in aerobic glycolysis in glioblastoma cells were determined by a series of experiments, such as Western blot, extracellular acidification rate (ECAR), lactate production, and intracellular ATP level assays. A xenograft mouse model was established to test our findings in vivo. RESULTS: The expression of FOXM1 and NOX4 was increased in glioma specimens compared with normal brain tissues and correlated with poor clinical outcomes. Aberrant mitochondrial reactive oxygen species (ROS) generation of NOX4 induced FOXM1 expression. Mechanistic studies demonstrated that NOX4-derived MitoROS exert their regulatory role on FOXM1 by mediating hypoxia-inducible factor 1α (HIF-1α) stabilization. Further research showed that NOX4-derived MitoROS-induced HIF-1α directly activates the transcription of FOXM1 and results in increased FOXM1 expression. Overexpression of NOX4 or FOXM1 promoted aerobic glycolysis, whereas knockdown of NOX4 or FOXM1 significantly suppressed aerobic glycolysis, in glioblastoma cells. NOX4-induced aerobic glycolysis was dependent on elevated FOXM1 expression, as FOXM1 knockdown abolished NOX4-induced aerobic glycolysis in glioblastoma cells both in vitro and in vivo. CONCLUSION: Increased expression of FOXM1 induced by NOX4-derived MitoROS plays a pivotal role in aerobic glycolysis, and our findings suggest that inhibition of NOX4-FOXM1 signaling may present a potential therapeutic target for glioblastoma treatment.


Assuntos
Neoplasias Encefálicas/metabolismo , Proteína Forkhead Box M1/metabolismo , Glioblastoma/metabolismo , NADPH Oxidase 4/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Efeito Warburg em Oncologia , Trifosfato de Adenosina/metabolismo , Animais , Western Blotting , Encéfalo/metabolismo , Neoplasias Encefálicas/terapia , Linhagem Celular Tumoral , Proteína Forkhead Box M1/antagonistas & inibidores , Glioblastoma/terapia , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Ácido Láctico/biossíntese , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Mitocôndrias/metabolismo , NADPH Oxidase 4/antagonistas & inibidores , Proteínas de Neoplasias/metabolismo , Transplante de Neoplasias
18.
Oxid Med Cell Longev ; 2021: 5549047, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34257808

RESUMO

Current studies on tumor progression focus on the roles of cytokines in the tumor microenvironment (TME), and recent research shows that transforming growth factor-ß1 (TGF-ß1) released from TME plays a pivotal role in tumor development and malignant transformation. The alteration in cellular metabolism is a hallmark of cancer, which not only provides cancer cells with ATP for fuel cellular reactions, but also generates metabolic intermediates for the synthesis of essential cellular ingredients, to support cell proliferation, migration, and invasion. Interestingly, we found a distinct metabolic change during TGF-ß1-induced epithelial-mesenchymal transition (EMT) in glioblastoma cells. Indeed, TGF-ß1 participates in metabolic reprogramming, and the molecular basis is still not well understood. NADPH oxidases 4 (NOX4), a member of the Nox family, also plays a key role in the biological effects of glioblastoma. However, the relationship between NOX4, TGF-ß1, and cellular metabolic changes during EMT in glioblastoma remains obscure. Here, our findings demonstrated that TGF-ß1 upregulated NOX4 expression accompanied by reactive oxygen species (ROS) through Smad-dependent signaling and then induced hypoxia-inducible factor 1α (HIF-1α) overexpression and nuclear accumulation resulting in metabolic reprogramming and promoting EMT. Besides, inhibition of glycolysis reversed EMT suggesting a causal relationship between TGF-ß1-induced metabolic changes and tumorigenesis. Moreover, TGF-ß1-induced metabolic reprogramming and EMT which modulated by NOX4/ROS were blocked when the phosphoinositide3-kinase (PI3K)/AKT/HIF-1α signaling pathways were inhibited. In conclusion, these suggest that NOX4/ROS induction by TGF-ß1 can be one of the main mechanisms mediating the metabolic reprogramming during EMT of glioblastoma cells and provide promising strategies for cancer therapy.


Assuntos
Glioblastoma/genética , NADPH Oxidase 4/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Animais , Transição Epitelial-Mesenquimal , Glioblastoma/patologia , Humanos , Masculino , Camundongos , Camundongos Nus , Transdução de Sinais , Transfecção
19.
Cell Discov ; 7(1): 12, 2021 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-33649311

RESUMO

In mammals, many organs lack robust regenerative abilities. Lost cells in impaired tissue could potentially be compensated by converting nearby cells in situ through in vivo reprogramming. Small molecule-induced cell reprogramming offers a temporally flexible and non-integrative strategy for altering cell fate, which is, in principle, favorable for in vivo reprogramming in organs with notoriously poor regenerative abilities, such as the brain. Here, we demonstrate that in the adult mouse brain, small molecules can reprogram astrocytes into neurons. The in situ chemically induced neurons resemble endogenous neurons in terms of neuron-specific marker expression, electrophysiological properties, and synaptic connectivity. Our study demonstrates the feasibility of in vivo chemical reprogramming in the adult mouse brain and provides a potential approach for developing neuronal replacement therapies.

20.
Int Immunopharmacol ; 93: 107374, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33517222

RESUMO

Sodium glucose cotransporter-2 (SGLT-2) inhibitor has been reported to exert a glucose-lowering effect in the peritoneum exposed to peritoneal dialysis solution. However, whether SGLT-2 inhibitors can regulate peritoneal fibrosis by suppressing TGF-ß/Smad signaling is unclear. We aimed to (i) examine the effect of the SGLT-2 inhibitor empagliflozin in reducing inflammatory reaction and preventing peritoneal dialysis solution-induced peritoneal fibrosis and (ii) elucidate the underlying mechanisms. High-glucose peritoneal dialysis solution or transforming growth factor ß1 (TGF-ß1) was used to induce peritoneal fibrosis in vivo, in a mouse peritoneal dialysis model (C57BL/6 mice) and in human peritoneal mesothelial cells in vitro, to stimulate extracellular matrix accumulation. The effects of empagliflozin and adeno-associated virus-RNAi, which is used to suppress SGLT-2 activity, on peritoneal fibrosis and extracellular matrix were evaluated. The mice that received chronic peritoneal dialysis solution infusions showed typical features of peritoneal fibrosis, including markedly increased peritoneal thickness, excessive matrix deposition, increased peritoneal permeability, and upregulated α-smooth muscle actin and collagen I expression. Empagliflozin treatment or downregulation of SGLT-2 expression significantly ameliorated these pathological changes. Inflammatory cytokines (TNF-α, IL-1ß, IL-6) and TGF-ß/Smad signaling-associated proteins, such as TGF-ß1 and phosphorylated Smad (p-Smad3), decreased in the empagliflozin-treated and SGLT-2 downregulated groups. In addition, empagliflozin treatment and downregulation of SGLT-2 expression reduced the levels of inflammatory cytokines (TNF-α, IL-1ß, IL-6), TGF-ß1, α-smooth muscle actin, collagen I, and p-Smad3 accumulation in human peritoneal mesothelial cells. Collectively, these results indicated that empagliflozin exerted a clear protective effect on high-glucose peritoneal dialysis-induced peritoneal fibrosis via suppressing TGF-ß/Smad signaling.


Assuntos
Compostos Benzidrílicos/uso terapêutico , Glucosídeos/uso terapêutico , Fibrose Peritoneal/tratamento farmacológico , Proteínas Smad/metabolismo , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Fator de Crescimento Transformador beta1/metabolismo , Animais , Compostos Benzidrílicos/farmacologia , Células Cultivadas , Citocinas/metabolismo , Glucose , Glucosídeos/farmacologia , Humanos , Masculino , Camundongos Endogâmicos C57BL , Diálise Peritoneal , Fibrose Peritoneal/genética , Fibrose Peritoneal/metabolismo , Fibrose Peritoneal/patologia , Peritônio/citologia , Peritônio/patologia , Transdução de Sinais/efeitos dos fármacos , Proteínas Smad/genética , Inibidores do Transportador 2 de Sódio-Glicose/farmacologia , Fator de Crescimento Transformador beta1/genética
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