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1.
iScience ; 26(9): 107734, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37680473

RESUMO

Tumor vasculature often exhibits disorder and inefficiency. Vascular normalization offers potential for alleviating hypoxia and optimizing drug delivery in tumors. However, identifying effective agents is hindered by a lack of robust screening. We aimed to establish a comprehensive method using the zebrafish functional xenograft vasculature platform (zFXVP) to visualize and quantify tumor vasculature changes. Employing zFXVP, we systematically screened compounds, identifying PF-502 as a robust vascular normalization agent. Mechanistic studies showed PF-502 induces endothelial cell-cycle arrest, streamlines vasculature, and activates Notch1 signaling, enhancing stability and hemodynamics. In murine models, PF-502 exhibited pronounced vascular normalization and improved drug delivery at a sub-maximum tolerated dose. These findings highlight zFXVP's utility and suggest PF-502 as a promising adjunctive for vascular normalization in clinical settings.

2.
PLoS Biol ; 21(5): e3002088, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37130348

RESUMO

Leukemogenesis is proposed to be a multistep process by which normal hematopoietic stem and progenitor cells are transformed into full-blown leukemic cells, the details of which are not fully understood. Here, we performed serial single-cell transcriptome analyses of preleukemic and leukemic cells (PLCs) and constructed the cellular and molecular transformation trajectory in a Myc-driven acute myeloid leukemia (AML) model in mice, which represented the transformation course in patients. We found that the Myc targets were gradually up-regulated along the trajectory. Among them were splicing factors, which showed stage-specific prognosis for AML patients. Furthermore, we dissected the detailed gene network of a tipping point for hematopoietic stem and progenitor cells (HSPCs) to generate initiating PLCs, which was characterized by dramatically increased splicing factors and unusual RNA velocity. In the late stage, PLCs acquired explosive heterogeneity through RNA alternative splicing. Among them, the Hsp90aa1hi subpopulation was conserved in both human and mouse AML and associated with poor prognosis. Exon 4 skipping of Tmem134 was identified in these cells. While the exon skipping product Tmem134ß promoted the cell cycle, full-length Tmem134α delayed tumorigenesis. Our study emphasized the critical roles of RNA splicing in the full process of leukemogenesis.


Assuntos
Leucemia Mieloide Aguda , Análise da Expressão Gênica de Célula Única , Humanos , Animais , Camundongos , Leucemia Mieloide Aguda/genética , Splicing de RNA/genética , RNA , Fatores de Processamento de RNA/genética , Transcriptoma/genética
3.
Front Pharmacol ; 14: 1276788, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38161699

RESUMO

The immune checkpoint inhibitor (ICI), anti-programmed cell death receptor-1 (PD-1) antibody, has gained widespread approval for treating various malignancies. Among the immune-related adverse reactions (irAEs) during ICI treatment, the lichenoid reaction is noteworthy. Sintilimab, a new PD-1 inhibitor, has secured approval in China for treating refractory non-Hodgkin's lymphoma, and phase I/II clinical trials for other solid tumors are ongoing both domestically and abroad. This paper presents a case of a mucocutaneous lichenoid reaction associated with sintilimab therapy, its diagnosis, and management. Our study, using multiplex immunofluorescence staining, reveals localized infiltration of CD4+ and CD8+ T lymphocytes in the subepithelial lamina propria region with upregulated PD-1 expression, implying an association between PD-1 expression upregulation and lichenoid reactions provoked by PD-1 monoclonal antibody. We provide a summary of clinical characteristics and treatment guidelines for lichenoid reactions induced by ICIs from previous reports, highlighting the success of a combined therapeutic regimen of oral antihistamines and topical corticosteroids in controlling symptoms without interrupting ICI treatment.

4.
Proc Natl Acad Sci U S A ; 119(50): e2201097119, 2022 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-36469766

RESUMO

Despite the robust healing capacity of the liver, regenerative failure underlies numerous hepatic diseases, including the JAG1 haploinsufficient disorder, Alagille syndrome (ALGS). Cholestasis due to intrahepatic duct (IHD) paucity resolves in certain ALGS cases but fails in most with no clear mechanisms or therapeutic interventions. We find that modulating jag1b and jag2b allele dosage is sufficient to stratify these distinct outcomes, which can be either exacerbated or rescued with genetic manipulation of Notch signaling, demonstrating that perturbations of Jag/Notch signaling may be causal for the spectrum of ALGS liver severities. Although regenerating IHD cells proliferate, they remain clustered in mutants that fail to recover due to a blunted elevation of Notch signaling in the distal-most IHD cells. Increased Notch signaling is required for regenerating IHD cells to branch and segregate into the peripheral region of the growing liver, where biliary paucity is commonly observed in ALGS. Mosaic loss- and-gain-of-function analysis reveals Sox9b to be a key Notch transcriptional effector required cell autonomously to regulate these cellular dynamics during IHD regeneration. Treatment with a small-molecule putative Notch agonist stimulates Sox9 expression in ALGS patient fibroblasts and enhances hepatic sox9b expression, rescues IHD paucity and cholestasis, and increases survival in zebrafish mutants, thereby providing a proof-of-concept therapeutic avenue for this disorder.


Assuntos
Síndrome de Alagille , Ductos Biliares Intra-Hepáticos , Transdução de Sinais , Animais , Humanos , Síndrome de Alagille/genética , Síndrome de Alagille/metabolismo , Proteína Jagged-1/genética , Proteína Jagged-1/metabolismo , Mosaicismo , Fatores de Transcrição SOX9/genética , Fatores de Transcrição SOX9/metabolismo , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Receptores Notch/genética , Receptores Notch/metabolismo , Regeneração , Ductos Biliares Intra-Hepáticos/citologia , Ductos Biliares Intra-Hepáticos/patologia , Fibroblastos
5.
Cell Rep ; 41(3): 111482, 2022 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-36261019

RESUMO

Gastric cancer (GC) is one of the most frequent and lethal malignancies in the world. However, our understanding of the mechanisms underlying its initiation and progression is limited. Here, we generate a series of primary GC models in mice with genome-edited gastric organoids, which elucidate the genetic drivers for sequential transformation from dysplasia to well-differentiated and poorly differentiated GC. Further, we find that the orthotopic GC, but not the subcutaneous GC even with the same genetic drivers, display remote metastasis, suggesting critical roles of the microenvironment in GC metastasis. Through single-cell RNA-seq analyses and functional studies, we show that the interaction between fibronectin 1 on stomach-specific macrophages and integrin a6ß4 on GC cells promotes remote metastases. Taken together, our studies propose a strategy to model GC and dissect the genetic and microenvironmental factors driving the full-range gastric tumorigenesis.


Assuntos
Fibronectinas , Neoplasias Gástricas , Camundongos , Animais , Linhagem Celular Tumoral , Carcinogênese/genética , Carcinogênese/patologia , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Transformação Celular Neoplásica , Integrinas , Microambiente Tumoral
6.
Cancer Cell ; 40(9): 1044-1059.e8, 2022 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-36099882

RESUMO

Cisplatin-based chemotherapy remains the primary treatment for unresectable and metastatic muscle-invasive bladder cancers (MIBCs). However, tumors frequently develop chemoresistance. Here, we established a primary and orthotopic MIBC mouse model with gene-edited organoids to recapitulate the full course of chemotherapy in patients. We found that partial squamous differentiation, called semi-squamatization, is associated with acquired chemoresistance in both mice and human MIBCs. Multi-omics analyses showed that cathepsin H (CTSH) is correlated with chemoresistance and semi-squamatization. Cathepsin inhibition by E64 treatment induces full squamous differentiation and pyroptosis, and thus specifically restrains chemoresistant MIBCs. Mechanistically, E64 treatment activates the tumor necrosis factor pathway, which is required for the terminal differentiation and pyroptosis of chemoresistant MIBC cells. Our study revealed that semi-squamatization is a type of lineage plasticity associated with chemoresistance, suggesting that differentiation via targeting of CTSH is a potential therapeutic strategy for the treatment of chemoresistant MIBCs.


Assuntos
Carcinoma de Células Escamosas , Neoplasias da Bexiga Urinária , Animais , Carcinoma de Células Escamosas/tratamento farmacológico , Diferenciação Celular , Cisplatino , Humanos , Camundongos , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/patologia
7.
Artigo em Inglês | MEDLINE | ID: mdl-35911170

RESUMO

Maoji Jiu (MJ), a medicinal wine, has been used commonly by the Chinese to enrich and nourish the blood. In this study, the aim is to examine the hematopoietic function of MJ and investigate its hematopoietic regulation mechanism. Thirty-six female Sprague-Dawley rats (200 ± 20 g) were randomly divided into six groups with six rats in each group. The blood deficiency model was induced by injecting hypodermically with N-acetylphenylhydrazine (APH) and injecting intraperitoneally with cyclophosphamide (CTX), and treatment drugs were given by oral gavage twice a day for continuous 10 days from the start of the experiments. The administration of MJ improved the levels of white blood cells (WBCs), red blood cells (RBCs), hemoglobin (HGB), and hematocrit (HCT) in the blood deficiency model rats. Hematopoietic effect involves regulating the antioxidant activity in the liver and the levels of Bcl-2, Bax, erythropoietin (EPO), transforming growth factor-beta-1 (TGF-ß1), and macrophage colony-stimulating factor (M-CSF) mRNA in spleen tissues to enhance extramedullary hematopoiesis. This study suggests that MJ has a beneficial effect on blood deficiency model rats.

8.
Mol Biomed ; 3(1): 18, 2022 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-35695994

RESUMO

The 'angiogenic switch' is critical for tumor progression. However, the pathological details and molecular mechanisms remain incompletely characterized. In this study, we established mammal xenografts in zebrafish to visually investigate the first vessel growth (angiogenic switch) in real-time, by inoculating tumor cells into the perivitelline space of live optically transparent Transgenic (flk1:EGFP) zebrafish larvae. Using this model, we found that hypoxia and hypoxia-inducible factor (HIF) signaling were unnecessary for the angiogenic switch, whereas vascular endothelial growth factor A gene (Vegfa) played a crucial role. Mechanistically, transcriptome analysis showed that the angiogenic switch was characterized by inhibition of translation, but not hypoxia. Phosphorylation of eukaryotic translation initiation factor 2 alpha (Eif2α) and the expression of Vegfa were increased in the angiogenic switch microtumors, and 3D tumor spheroids, and puromycin-treated tumor cells. Vegfa overexpression promoted early onset of the angiogenic switch, whereas Vegfa knockout prevented the first tumor vessel from sprouting. Pretreatment of tumor cells with puromycin promoted the angiogenic switch in vivo similarly to Vegfa overexpression, whereas Vegfa knockdown suppressed the increase. This study provides direc and dynamic in vivo evidences that inhibition of translation, but not hypoxia or HIF signaling promotes the angiogenic switch in tumor by increasing Vegfa transcription.

9.
Nat Cancer ; 3(6): 753-767, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35449309

RESUMO

Small cell lung cancer (SCLC) is notorious for its early and frequent metastases, which contribute to it as a recalcitrant malignancy. To understand the molecular mechanisms underlying SCLC metastasis, we generated SCLC mouse models with orthotopically transplanted genome-edited lung organoids and performed multiomics analyses. We found that a deficiency of KMT2C, a histone H3 lysine 4 methyltransferase frequently mutated in extensive-stage SCLC, promoted multiple-organ metastases in mice. Metastatic and KMT2C-deficient SCLC displayed both histone and DNA hypomethylation. Mechanistically, KMT2C directly regulated the expression of DNMT3A, a de novo DNA methyltransferase, through histone methylation. Forced DNMT3A expression restrained metastasis of KMT2C-deficient SCLC through repressing metastasis-promoting MEIS/HOX genes. Further, S-(5'-adenosyl)-L-methionine, the common cofactor of histone and DNA methyltransferases, inhibited SCLC metastasis. Thus, our study revealed a concerted epigenetic reprogramming of KMT2C- and DNMT3A-mediated histone and DNA hypomethylation underlying SCLC metastasis, which suggested a potential epigenetic therapeutic vulnerability.


Assuntos
DNA Metiltransferase 3A , Histona-Lisina N-Metiltransferase , Neoplasias Pulmonares , Carcinoma de Pequenas Células do Pulmão , Animais , DNA/metabolismo , DNA (Citosina-5-)-Metiltransferases/genética , Metilação de DNA/genética , DNA Metiltransferase 3A/genética , Metilases de Modificação do DNA/genética , Epigênese Genética/genética , Histona-Lisina N-Metiltransferase/deficiência , Histona-Lisina N-Metiltransferase/genética , Histonas/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Metiltransferases/genética , Camundongos , Carcinoma de Pequenas Células do Pulmão/genética , Carcinoma de Pequenas Células do Pulmão/secundário
10.
Front Oncol ; 12: 852095, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35392237

RESUMO

In this study, we aimed to reveal the resistance mechanism of hepatocellular carcinoma (HCC) cells to sorafenib by exploring the effect of FNDC5 on sorafenib-induced ferroptosis in HCC cells. We compared the expression level of FNDC5 between sorafenib-resistant and sorafenib-sensitive HCC cell lines and the level of ferroptosis between the groups after treatment with sorafenib. We knocked down FNDC5 in drug-resistant cell lines and overexpressed it in sorafenib-sensitive HCC cell lines to further demonstrate the role of FNDC5 in sorafenib-induced ferroptosis. Using PI3K inhibitors, we revealed the specific mechanism by which FNDC5 functions. In addition, we verified our findings obtained in in vitro experiments using a subcutaneous tumorigenic nude mouse model. The findings revealed that FNDC5 inhibits sorafenib-induced ferroptosis in HCC cells. In addition, FNDC5 activated the PI3K/Akt pathway, which in turn promoted the nuclear translocation of Nrf2 and increased the intracellular antioxidant response, thereby conferring resistance to ferroptosis. Our study provides novel insights for improving the efficacy of sorafenib.

11.
Dis Model Mech ; 15(4)2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35199829

RESUMO

An accurate prediction of the intracranial infiltration tendency and drug response of individual glioblastoma (GBM) cells is essential for personalized prognosis and treatment for this disease. However, the clinical utility of mouse patient-derived orthotopic xenograft (PDOX) models remains limited given current technical constraints, including difficulty in generating sufficient sample numbers from small tissue samples and a long latency period for results. To overcome these issues, we established zebrafish GBM xenografts of diverse origin, which can tolerate intracranial engraftment and maintain their unique histological features. Subsequent single-cell RNA-sequencing (scRNA-seq) analysis confirmed significant transcriptional identity to that of invading GBM microtumors observed in the proportionally larger brains of model animals and humans. Endothelial scRNA-seq confirmed that the zebrafish blood-brain barrier is homologous to the mammalian blood-brain barrier. Finally, we established a rapid and efficient zebrafish PDOX (zPDOX) model, which can predict long-term outcomes of GBM patients within 20 days. The zPDOX model provides a novel avenue for precision medicine of GBM, especially for the evaluation of intracranial infiltration tendency and prediction of individual drug sensitivity.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Animais , Neoplasias Encefálicas/patologia , Modelos Animais de Doenças , Glioblastoma/patologia , Xenoenxertos , Humanos , Mamíferos , Camundongos , Ensaios Antitumorais Modelo de Xenoenxerto , Peixe-Zebra
12.
Hepatology ; 75(3): 567-583, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34569629

RESUMO

BACKGROUND AND AIMS: Alagille Syndrome (ALGS) is a congenital disorder caused by mutations in the Notch ligand gene JAGGED1, leading to neonatal loss of intrahepatic duct (IHD) cells and cholestasis. Cholestasis can resolve in certain patients with ALGS, suggesting regeneration of IHD cells. However, the mechanisms driving IHD cell regeneration following Jagged loss remains unclear. Here, we show that cholestasis due to developmental loss of IHD cells can be consistently phenocopied in zebrafish with compound jagged1b and jagged2b mutations or knockdown. APPROACH AND RESULTS: Leveraging the transience of jagged knockdown in juvenile zebrafish, we find that resumption of Jagged expression leads to robust regeneration of IHD cells through a Notch-dependent mechanism. Combining multiple lineage tracing strategies with whole-liver three-dimensional imaging, we demonstrate that the extrahepatic duct (EHD) is the primary source of multipotent progenitors that contribute to the regeneration, but not to the development, of IHD cells. Hepatocyte-to-IHD cell transdifferentiation is possible but rarely detected. Progenitors in the EHD proliferate and migrate into the liver with Notch signaling loss and differentiate into IHD cells if Notch signaling increases. Tissue-specific mosaic analysis with an inducible dominant-negative Fgf receptor suggests that Fgf signaling from the surrounding mesenchymal cells maintains this extrahepatic niche by directly preventing premature differentiation and allocation of EHD progenitors to the liver. Indeed, transcriptional profiling and functional analysis of adult mouse EHD organoids uncover their distinct differentiation and proliferative potential relative to IHD organoids. CONCLUSIONS: Our data show that IHD cells regenerate upon resumption of Jagged/Notch signaling, from multipotent progenitors originating from an Fgf-dependent extrahepatic stem cell niche. We posit that if Jagged/Notch signaling is augmented, through normal stochastic variation, gene therapy, or a Notch agonist, regeneration of IHD cells in patients with ALGS may be enhanced.


Assuntos
Síndrome de Alagille , Ductos Biliares Extra-Hepáticos , Ductos Biliares Intra-Hepáticos , Proteínas de Ligação ao Cálcio , Proteína Jagged-1 , Regeneração Hepática/fisiologia , Receptores Notch/metabolismo , Proteínas de Peixe-Zebra , Síndrome de Alagille/genética , Síndrome de Alagille/metabolismo , Animais , Ductos Biliares Extra-Hepáticos/crescimento & desenvolvimento , Ductos Biliares Extra-Hepáticos/fisiologia , Ductos Biliares Intra-Hepáticos/crescimento & desenvolvimento , Ductos Biliares Intra-Hepáticos/fisiologia , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/metabolismo , Transdiferenciação Celular , Modelos Animais de Doenças , Humanos , Proteína Jagged-1/genética , Proteína Jagged-1/metabolismo , Fígado/crescimento & desenvolvimento , Fígado/metabolismo , Receptores de Fatores de Crescimento de Fibroblastos/metabolismo , Transdução de Sinais , Peixe-Zebra , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
14.
Cancer Discov ; 11(1): 194-207, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32978226

RESUMO

Chromosome copy-number variations are a hallmark of cancer. Among them, the prevalent chromosome 17p deletions are associated with poor prognosis and can promote tumorigenesis more than TP53 loss. Here, we use multiple functional genetic strategies and identify a new 17p tumor suppressor gene (TSG), plant homeodomain finger protein 23 (PHF23). Its deficiency impairs B-cell differentiation and promotes immature B-lymphoblastic malignancy. Mechanistically, we demonstrate that PHF23, an H3K4me3 reader, directly binds the SIN3-HDAC complex through its N-terminus and represses its deacetylation activity on H3K27ac. Thus, the PHF23-SIN3-HDAC (PSH) complex coordinates these two major active histone markers for the activation of downstream TSGs and differentiation-related genes. Furthermore, dysregulation of the PSH complex is essential for the development and maintenance of PHF23-deficient and 17p-deleted tumors. Hence, our study reveals a novel epigenetic regulatory mechanism that contributes to the pathology of 17p-deleted cancers and suggests a susceptibility in this disease. SIGNIFICANCE: We identify PHF23, encoding an H3K4me3 reader, as a new TSG on chromosome 17p, which is frequently deleted in human cancers. Mechanistically, PHF23 forms a previously unreported histone-modifying complex, the PSH complex, which regulates gene activation through a synergistic link between H3K4me3 and H3K27ac.This article is highlighted in the In This Issue feature, p. 1.


Assuntos
Aberrações Cromossômicas , Deleção Cromossômica , Transformação Celular Neoplásica/genética , Cromossomos , Epigênese Genética , Proteínas de Homeodomínio , Humanos
15.
Cell Metab ; 33(2): 395-410.e4, 2021 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-33357457

RESUMO

Regenerative capacity is frequently impaired in aged organs. Stress to aged organs often causes scar formation (fibrosis) at the expense of regeneration. It remains to be defined how hematopoietic and vascular cells contribute to aging-induced regeneration to fibrotic transition. Here, we find that aging aberrantly reprograms the crosstalk between hematopoietic and vascular cells to impede the regenerative capacity and enhance fibrosis. In aged lung, liver, and kidney, induction of Neuropilin-1/hypoxia-inducible-factor 2α (HIF2α) suppresses anti-thrombotic and anti-inflammatory endothelial protein C receptor (EPCR) pathway, leading to formation of pro-fibrotic platelet-macrophage rosette. Activated platelets via supplying interleukin 1α synergize with endothelial-produced angiocrine chemokine to recruit fibrogenic TIMP1high macrophages. In mouse models, genetic targeting of endothelial Neuropilin-1-HIF2α, platelet interleukin 1α, or macrophage TIMP1 normalized the pro-fibrotic hematopoietic-vascular niche and restored the regenerative capacity of old organs. Targeting of aberrant endothelial node molecules might help propel "regeneration without scarring" in the repair of multiple organs.


Assuntos
Envelhecimento/metabolismo , Fibrose/metabolismo , Nicho de Células-Tronco , Animais , Camundongos , Camundongos Transgênicos
16.
Acta Pharm Sin B ; 10(8): 1453-1475, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32963943

RESUMO

Angiokinases, such as vascular endothelial-, fibroblast- and platelet-derived growth factor receptors (VEGFRs, FGFRs and PDGFRs) play crucial roles in tumor angiogenesis. Anti-angiogenesis therapy using multi-angiokinase inhibitor has achieved great success in recent years. In this study, we presented the design, synthesis, target identification, molecular mechanism, pharmacodynamics (PD) and pharmacokinetics (PK) research of a novel triple-angiokinase inhibitor WXFL-152. WXFL-152, identified from a series of 4-oxyquinoline derivatives based on a structure-activity relationship study, inhibited the proliferation of vascular endothelial cells (ECs) and pericytes by blocking the angiokinase signals VEGF/VEGFR2, FGF/FGFRs and PDGF/PDGFRß simultaneously in vitro. Significant anticancer effects of WXFL-152 were confirmed in multiple preclinical tumor xenograft models, including a patient-derived tumor xenograft (PDX) model. Pharmacokinetic studies of WXFL-152 demonstrated high favourable bioavailability with single-dose and continuous multi-dose by oral administration in rats and beagles. In conclusion, WXFL-152, which is currently in phase Ib clinical trials, is a novel and effective triple-angiokinase inhibitor with clear PD and PK in tumor therapy.

18.
Sci Rep ; 10(1): 614, 2020 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-31953486

RESUMO

Toxicity to central nervous system tissues is the common side effects for radiotherapy of brain tumor. The radiation toxicity has been thought to be related to the damage of cerebral endothelium. However, because of lacking a suitable high-resolution vivo model, cellular response of cerebral capillaries to radiation remained unclear. Here, we present the flk:eGFP transgenic zebrafish larvae as a feasible model to study the radiation toxicity to cerebral capillary. We showed that, in living zebrafish larvae, radiation could induce acute cerebral capillary shrinkage and blood-flow obstruction, resulting brain hypoxia and glycolysis retardant. Although in vivo neuron damage was also observed after the radiation exposure, further investigation found that they didn't response to the same dosage of radiation in vitro, indicating that radiation induced neuron damage was a secondary-effect of cerebral vascular function damage. In addition, transgenic labeling and qPCR results showed that the radiation-induced acute cerebral endothelial damage was correlated with intensive endothelial autophagy. Different autophagy inhibitors could significantly alleviate the radiation-induced cerebral capillary damage and prolong the survival of zebrafish larvae. Therefore, we showed that radiation could directly damage cerebral capillary, resulting to blood flow deficiency and neuron death, which suggested endothelial autophagy as a potential target for radiation-induced brain toxicity.


Assuntos
Lesões Encefálicas/metabolismo , Endotélio/citologia , Proteínas de Fluorescência Verde/genética , Proteínas Associadas aos Microtúbulos/genética , Neurônios/citologia , Fatores de Transcrição/genética , Proteínas de Peixe-Zebra/genética , Animais , Animais Geneticamente Modificados , Autofagia , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Encéfalo/efeitos da radiação , Lesões Encefálicas/diagnóstico por imagem , Lesões Encefálicas/etiologia , Lesões Encefálicas/genética , Células Cultivadas , Angiografia Cerebral , Técnicas de Cocultura , Irradiação Craniana/efeitos adversos , Modelos Animais de Doenças , Endotélio/efeitos da radiação , Proteínas de Fluorescência Verde/metabolismo , Microscopia Confocal , Proteínas Associadas aos Microtúbulos/metabolismo , Neurônios/efeitos da radiação , Fatores de Transcrição/metabolismo , Peixe-Zebra , Proteínas de Peixe-Zebra/metabolismo
19.
Nat Commun ; 10(1): 5083, 2019 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-31704937

RESUMO

Nanoscale transport through nanopores and live-cell membranes plays a vital role in both key biological processes as well as biosensing and DNA sequencing. Active translocation of DNA through these nanopores usually needs enzyme assistance. Here we present a nanopore derived from truncated helicase E1 of bovine papillomavirus (BPV) with a lumen diameter of c.a. 1.3 nm. Cryogenic electron microscopy (cryo-EM) imaging and single channel recording confirm its insertion into planar lipid bilayer (BLM). The helicase nanopore in BLM allows the passive single-stranded DNA (ssDNA) transport and retains the helicase activity in vitro. Furthermore, we incorporate this helicase nanopore into the live cell membrane of HEK293T cells, and monitor the ssDNA delivery into the cell real-time at single molecule level. This type of nanopore is expected to provide an interesting tool to study the biophysics of biomotors in vitro, with potential applications in biosensing, drug delivery and real-time single cell analysis.


Assuntos
DNA Helicases/metabolismo , DNA de Cadeia Simples/metabolismo , Proteínas de Ligação a DNA/metabolismo , Bicamadas Lipídicas/metabolismo , Nanoporos/ultraestrutura , Proteínas Virais/metabolismo , Microscopia Crioeletrônica , DNA Helicases/ultraestrutura , Proteínas de Ligação a DNA/ultraestrutura , Células HEK293 , Humanos , Microscopia Confocal , Técnicas de Patch-Clamp , Transfecção , Proteínas Virais/ultraestrutura
20.
Exp Ther Med ; 16(4): 3445-3451, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30233694

RESUMO

The aim of the present study was to measure the expression of Claudin (CLDN) 1 in nasopharyngeal carcinoma (NPC) and to determine its biological function and mechanism of action. Reverse transcription-quantitative polymerase chain reaction and western blotting were performed to measure the expression of CLDN1 mRNA and protein, respectively, in the immortalized human nasopharyngeal epithelial cell line NP69 and NPC-TW01 cells. Subsequently, small interfering RNA against CLDN1 and the LV-GFP-PURO-CLDN1 lentivirus were transfected into NPC-TW01 cells. Western blotting was used to determine the effects of CLDN1 down- and upregulation on the expression of the epithelial mesenchymal transition (EMT) markers E-cadherin and vimentin. In addition, the effect of CLDN1 on the expression of ß-Catenin was determined. The results demonstrated that levels of CLDN1 mRNA and protein in NPC cells were significantly higher than in NP69 cells. Furthermore, the downregulation of CLDN1 inhibited the proliferation, invasion and migration of NPC-TW01 cells. The results of western blotting demonstrated that the downregulation of CLDN1 resulted in the upregulation of E-cadherin and inhibition of vimentin in NPC-TW01 cells. By contrast, the overexpression of CLDN1 resulted in the downregulation of E-cadherin and upregulation of vimentin in NPC-TW01 cells. The downregulation of ß-catenin attenuated the cancer-promoting effect of CLDN1 on NPC-TW01 cells, whereas the upregulation of ß-catenin reversed the tumor-suppressing effect of CLDN1 downregulation on NPC-TW01 cells. The results of the present study therefore demonstrate that CLDN1 expression is elevated in NPC cells. As an oncogene, CLDN1 promotes the proliferation, invasion and migration of NPC cells by upregulating the expression and nuclear entry of ß-catenin.

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