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1.
bioRxiv ; 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38405985

RESUMO

A central problem in cancer immunotherapy with immune checkpoint blockade (ICB) is the development of resistance, which affects 50% of patients with metastatic melanoma1,2. T cell exhaustion, resulting from chronic antigen exposure in the tumour microenvironment, is a major driver of ICB resistance3. Here, we show that CD38, an ecto-enzyme involved in nicotinamide adenine dinucleotide (NAD+) catabolism, is highly expressed in exhausted CD8+ T cells in melanoma and is associated with ICB resistance. Tumour-derived CD38hiCD8+ T cells are dysfunctional, characterised by impaired proliferative capacity, effector function, and dysregulated mitochondrial bioenergetics. Genetic and pharmacological blockade of CD38 in murine and patient-derived organotypic tumour models (MDOTS/PDOTS) enhanced tumour immunity and overcame ICB resistance. Mechanistically, disrupting CD38 activity in T cells restored cellular NAD+ pools, improved mitochondrial function, increased proliferation, augmented effector function, and restored ICB sensitivity. Taken together, these data demonstrate a role for the CD38-NAD+ axis in promoting T cell exhaustion and ICB resistance, and establish the efficacy of CD38 directed therapeutic strategies to overcome ICB resistance using clinically relevant, patient-derived 3D tumour models.

2.
J Immunother Cancer ; 12(1)2024 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-38233101

RESUMO

BACKGROUND: Immune-related adverse events (irAEs) are major barriers of clinical management and further development of immune checkpoint inhibitors (ICIs) for cancer therapy. Therefore, biomarkers associated with the onset of severe irAEs are needed. In this study, we aimed to identify immune features detectable in peripheral blood and associated with the development of severe irAEs that required clinical intervention. METHODS: We used a 43-marker mass cytometry panel to characterize peripheral blood mononuclear cells from 28 unique patients with melanoma across 29 lines of ICI therapy before treatment (baseline), before the onset of irAEs (pre-irAE) and at the peak of irAEs (irAE-max). In the 29 lines of ICI therapy, 18 resulted in severe irAEs and 11 did not. RESULTS: Unsupervised and gated population analysis showed that patients with severe irAEs had a higher frequency of CD4+ naïve T cells and lower frequency of CD16+ natural killer (NK) cells at all time points. Gated population analysis additionally showed that patients with severe irAEs had fewer T cell immunoreceptor with Ig and ITIM domain (TIGIT+) regulatory T cells at baseline and more activated CD38+ CD4+ central memory T cells (TCM) and CD39+ and Human Leukocyte Antigen-DR Isotype (HLA-DR)+ CD8+ TCM at peak of irAEs. The differentiating immune features at baseline were predominantly seen in patients with gastrointestinal and cutaneous irAEs and type 1 diabetes. Higher frequencies of CD4+ naïve T cells and lower frequencies of CD16+ NK cells were also associated with clinical benefit to ICI therapy. CONCLUSIONS: This study demonstrates that high-dimensional immune profiling can reveal novel blood-based immune signatures associated with risk and mechanism of severe irAEs. Development of severe irAEs in melanoma could be the result of reduced immune inhibitory capacity pre-ICI treatment, resulting in more activated TCM cells after treatment.


Assuntos
Melanoma , Linfócitos T Reguladores , Humanos , Inibidores de Checkpoint Imunológico/efeitos adversos , Leucócitos Mononucleares , Melanoma/tratamento farmacológico , Células Matadoras Naturais
3.
Cell Death Dis ; 14(10): 660, 2023 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-37816733

RESUMO

Colorectal cancer (CRC) is a prevalent malignancy worldwide and is associated with a high mortality rate. Changes in bioenergy metabolism, such as the Warburg effect, are often observed in CRC. Aldolase B (ALDOB) has been identified as a potential regulator of these changes, but its exact role in CRC cell behavior and bioenergetic homeostasis is not fully understood. To investigate this, two cohorts of CRC patients were analyzed independently. The results showed that higher ALDOB expression was linked to unfavorable prognosis, increased circulating carcinoembryonic antigen (CEA) levels, and altered bioenergetics in CRC. Further analysis using cell-based assays demonstrated that ALDOB promoted cell proliferation, chemoresistance, and increased expression of CEA in CRC cells. The activation of pyruvate dehydrogenase kinase-1 (PDK1) by ALDOB-induced lactagenesis and secretion, which in turn mediated the effects on CEA expression. Secreted lactate was found to enhance lactate dehydrogenase B (LDHB) expression in adjacent cells and to be a crucial modulator of ALDOB-mediated phenotypes. Additionally, the effect of ALDOB on CEA expression was downstream of the bioenergetic changes mediated by secreted lactate. The study also identified CEA cell adhesion molecule-6 (CEACAM6) as a downstream effector of ALDOB that controlled CRC cell proliferation and chemoresistance. Notably, CEACAM6 activation was shown to enhance protein stability through lysine lactylation, downstream of ALDOB-mediated lactagenesis. The ALDOB/PDK1/lactate/CEACAM6 axis plays an essential role in CRC cell behavior and bioenergetic homeostasis, providing new insights into the involvement of CEACAM6 in CRC and the Warburg effect. These findings may lead to the development of new treatment strategies for CRC patients.


Assuntos
Neoplasias Colorretais , Frutose-Bifosfato Aldolase , Humanos , Frutose-Bifosfato Aldolase/metabolismo , Antígeno Carcinoembrionário , Resistencia a Medicamentos Antineoplásicos , Moléculas de Adesão Celular , Neoplasias Colorretais/patologia , Lactatos , Linhagem Celular Tumoral , Antígenos CD/genética , Proteínas Ligadas por GPI
4.
Life Sci Alliance ; 6(9)2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37433644

RESUMO

The nuclear envelope (NE) is a subdomain of the ER with prominent roles in nuclear organization, which are largely mediated by its distinctive protein composition. We developed methods to reveal low-abundance transmembrane (TM) proteins concentrated at the NE relative to the peripheral ER. Using label-free proteomics that compared isolated NEs with cytoplasmic membranes, we first identified proteins with apparent NE enrichment. In subsequent authentication, ectopically expressed candidates were analyzed by immunofluorescence microscopy to quantify their targeting to the NE in cultured cells. Ten proteins from a validation set were found to associate preferentially with the NE, including oxidoreductases, enzymes for lipid biosynthesis, and regulators of cell growth and survival. We determined that one of the validated candidates, the palmitoyltransferase Zdhhc6, modifies the NE oxidoreductase Tmx4 and thereby modulates its NE levels. This provides a functional rationale for the NE concentration of Zdhhc6. Overall, our methodology has revealed a group of previously unrecognized proteins concentrated at the NE and additional candidates. Future analysis of these can potentially unveil new mechanistic pathways associated with the NE.


Assuntos
Membrana Nuclear , Proteômica , Membrana Celular , Ciclo Celular , Proliferação de Células
5.
bioRxiv ; 2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36824861

RESUMO

The nuclear envelope (NE) is a subdomain of the ER with prominent roles in nuclear organization, largely mediated by its distinctive protein composition. We developed methods to reveal novel, low abundance transmembrane (TM) proteins concentrated at the NE relative to the peripheral ER. Using label-free proteomics that compared isolated NEs to cytoplasmic membranes, we first identified proteins with apparent NE enrichment. In subsequent authentication, ectopically expressed candidates were analyzed by immunofluorescence microscopy to quantify their targeting to the NE in cultured cells. Ten proteins from a validation set were found to associate preferentially with the NE, including oxidoreductases, enzymes for lipid biosynthesis and regulators of cell growth and survival. We determined that one of the validated candidates, the palmitoyltransferase Zdhhc6, modifies the NE oxidoreductase Tmx4 and thereby modulates its NE levels. This provides a functional rationale for the NE concentration of Zdhhc6. Overall, our methodology has revealed a group of previously unrecognized proteins concentrated at the NE and additional candidates. Future analysis of these can potentially unveil new mechanistic pathways associated with the NE.

6.
Am J Chin Med ; 50(7): 1845-1868, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36185015

RESUMO

Tanshinone IIA (TanIIA) has neuroprotective effects against cerebral ischemia reperfusion injury (CIRI), but its clinical application is limited due to poor water solubility and robust first pass elimination property. In this study, we developed microemulsion loaded with TanIIA (TanIIA ME) to break through these limitations, and explored the neuroprotective effect of TanIIA ME against CIRI and the epigenetic regulation mechanism of this neuroprotection. In vivo, middle cerebral artery occlusion (MCAO) models were treated with TanIIA ME and TanIIA solution or sodium valproate as a control. The effect of TanIIA ME on HDAC activity was determined by ELISA assay. In addition, we used primary hippocampal neurons to establish oxygen-glucose deprivation and reoxygenation (OGD/R) models. Lactate dehydrogenase (LDH) assay and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay were performed to investigate the neuroprotective efficacy of TanIIA ME. Subsequently, the expression of H3K18ac, H4K8ac, NMDAR1, caspase-3, and MAP-2 were investigated in MCAO or OGD/R models treated with TanIIA ME, TanIIA solution or sodium valproate. In vivo experimental results indicated that TanIIA ME significantly reduced neurological scores, infarction volume, and HDAC activity compared with TanIIA solution and MCAO group, accompanied by upregulation of H3K18ac, H4K8ac, and MAP-2 expression and downregulation of NMDAR1 and caspase-3 expression. Additionally, in OGD/R models, the results demonstrated that TanIIA ME treatment had a better neuroprotective effect along with increased H3K18ac, H4K8ac, and MAP-2 expression and decreased NMDAR1 and caspase-3 expression, compared with the other treatments except sodium valproate. Overall, TanIIA ME treatment exhibited superior efficacy in protecting against CIRI through mechanisms that might involve the inhibition of NMDAR1 and caspase-3 expression and the enhancement of MAP-2 expression by regulating histone H3K18 and H4K8 acetylation. Thus, TanIIA ME could be potentially used to develop a promising drug for the treatment of ischemic stroke.


Assuntos
Isquemia Encefálica , Fármacos Neuroprotetores , Traumatismo por Reperfusão , Humanos , Caspase 3/genética , Caspase 3/metabolismo , Fármacos Neuroprotetores/farmacologia , Ácido Valproico/farmacologia , Ácido Valproico/uso terapêutico , Epigênese Genética , Apoptose , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/prevenção & controle , Infarto da Artéria Cerebral Média/tratamento farmacológico , Infarto da Artéria Cerebral Média/complicações , Glucose , Isquemia Encefálica/genética
7.
J Biomed Sci ; 29(1): 74, 2022 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-36154922

RESUMO

The major concept of "oxidative stress" is an excess elevated level of reactive oxygen species (ROS) which are generated from vigorous metabolism and consumption of oxygen. The precise harmonization of oxidative stresses between mitochondria and other organelles in the cell is absolutely vital to cell survival. Under oxidative stress, ROS produced from mitochondria and are the major mediator for tumorigenesis in different aspects, such as proliferation, migration/invasion, angiogenesis, inflammation, and immunoescape to allow cancer cells to adapt to the rigorous environment. Accordingly, the dynamic balance of oxidative stresses not only orchestrate complex cell signaling events in cancer cells but also affect other components in the tumor microenvironment (TME). Immune cells, such as M2 macrophages, dendritic cells, and T cells are the major components of the immunosuppressive TME from the ROS-induced inflammation. Based on this notion, numerous strategies to mitigate oxidative stresses in tumors have been tested for cancer prevention or therapies; however, these manipulations are devised from different sources and mechanisms without established effectiveness. Herein, we integrate current progress regarding the impact of mitochondrial ROS in the TME, not only in cancer cells but also in immune cells, and discuss the combination of emerging ROS-modulating strategies with immunotherapies to achieve antitumor effects.


Assuntos
Neoplasias , Microambiente Tumoral , Humanos , Inflamação , Neoplasias/metabolismo , Estresse Oxidativo , Oxigênio , Espécies Reativas de Oxigênio/metabolismo
8.
J Proteome Res ; 21(9): 2197-2210, 2022 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-35972904

RESUMO

Emerin and lamin B receptor (LBR) are abundant transmembrane proteins of the nuclear envelope that are concentrated at the inner nuclear membrane (INM). Although both proteins interact with chromatin and nuclear lamins, they have distinctive biochemical and functional properties. Here, we have deployed proximity labeling using the engineered biotin ligase TurboID (TbID) and quantitative proteomics to compare the neighborhoods of emerin and LBR in cultured mouse embryonic fibroblasts. Our analysis revealed 232 high confidence proximity partners that interact selectively with emerin and/or LBR, 49 of which are shared by both. These included previously characterized NE-concentrated proteins, as well as a host of additional proteins not previously linked to emerin or LBR functions. Many of these are TM proteins of the ER, including two E3 ubiquitin ligases. Supporting these results, we found that 11/12 representative proximity relationships identified by TbID also were detected at the NE with the proximity ligation assay. Overall, this work presents methodology that may be used for large-scale mapping of the landscape of the INM and reveals a group of new proteins with potential functional connections to emerin and LBR.


Assuntos
Lamina Tipo A , Proteômica , Animais , Fibroblastos/metabolismo , Lamina Tipo A/metabolismo , Proteínas de Membrana , Camundongos , Proteínas Nucleares , Receptores Citoplasmáticos e Nucleares , Receptor de Lamina B
9.
J Immunother Cancer ; 8(2)2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33268351

RESUMO

BACKGROUND: Mitochondrial Lon is a chaperone and DNA-binding protein that functions in protein quality control and stress response pathways. The level of Lon regulates mitochondrial DNA (mtDNA) metabolism and the production of mitochondrial reactive oxygen species (ROS). However, there is little information in detail on how mitochondrial Lon regulates ROS-dependent cancer immunoescape through mtDNA metabolism in the tumor microenvironment (TME). METHODS: We explored the understanding of the intricate interplay between mitochondria and the innate immune response in the inflammatory TME. RESULTS: We found that oxidized mtDNA is released into the cytosol when Lon is overexpressed and then it induces interferon (IFN) signaling via cGAS-STING-TBK1, which upregulates PD-L1 and IDO-1 expression to inhibit T-cell activation. Unexpectedly, upregulation of Lon also induces the secretion of extracellular vehicles (EVs), which carry mtDNA and PD-L1. Lon-induced EVs further induce the production of IFN and IL-6 from macrophages, which attenuates T-cell immunity in the TME. CONCLUSIONS: The levels of mtDNA and PD-L1 in EVs in patients with oral cancer function as a potential diagnostic biomarker for anti-PD-L1 immunotherapy. Our studies provide an insight into the immunosuppression on mitochondrial stress and suggest a therapeutic synergy between anti-inflammation therapy and immunotherapy in cancer.


Assuntos
Antígeno B7-H1/metabolismo , DNA Mitocondrial/metabolismo , Vesículas Extracelulares/metabolismo , Interferons/metabolismo , Proteínas de Membrana/metabolismo , Receptor de Morte Celular Programada 1/metabolismo , Animais , Antígeno B7-H1/imunologia , Biomarcadores Tumorais/imunologia , Biomarcadores Tumorais/metabolismo , DNA Mitocondrial/imunologia , Vesículas Extracelulares/imunologia , Humanos , Interferons/imunologia , Masculino , Melanoma Experimental/imunologia , Melanoma Experimental/metabolismo , Proteínas de Membrana/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Receptor de Morte Celular Programada 1/imunologia , Células RAW 264.7 , Transdução de Sinais , Transfecção , Microambiente Tumoral
10.
BMC Pregnancy Childbirth ; 20(1): 538, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32933509

RESUMO

BACKGROUND: We aimed to develop and validate a nomogram for effective prediction of vaginal birth after cesarean (VBAC) and guide future clinical application. METHODS: We retrospectively analyzed data from hospitalized pregnant women who underwent trial of labor after cesarean (TOLAC), at the Fujian Provincial Maternity and Children's Hospital, between October 2015 and October 2017. Briefly, we included singleton pregnant women, at a gestational age above 37 weeks who underwent a primary cesarean section, in the study. We then extracted their sociodemographic data and clinical characteristics, and randomly divided the samples into training and validation sets. We employed the least absolute shrinkage and selection operator (LASSO) regression to select variables and construct VBAC success rate in the training set. Thereafter, we validated the nomogram using the concordance index (C-index), decision curve analysis (DCA), and calibration curves. Finally, we adopted the Grobman's model to perform comparisons with published VBAC prediction models. RESULTS: Among the 708 pregnant women included according to inclusion criteria, 586 (82.77%) patients were successfully for VBAC. Multivariate logistic regression models revealed that maternal height (OR, 1.11; 95% CI, 1.04 to 1.19), maternal BMI at delivery (OR, 0.89; 95% CI, 0.79 to 1.00), fundal height (OR, 0.71; 95% CI, 0.58 to 0.88), cervix Bishop score (OR, 3.27; 95% CI, 2.49 to 4.45), maternal age at delivery (OR, 0.90; 95% CI, 0.82 to 0.98), gestational age (OR, 0.33; 95% CI, 0.17 to 0.62) and history of vaginal delivery (OR, 2.92; 95% CI, 1.42 to 6.48) were independently associated with successful VBAC. The constructed predictive model showed better discrimination than that from the Grobman's model in the validation series (c-index 0.906 VS 0.694, respectively). On the other hand, decision curve analysis revealed that the new model had better clinical net benefits than the Grobman's model. CONCLUSIONS: VBAC will aid in reducing the rate of cesarean sections in China. In clinical practice, the TOLAC prediction model will help improve VBAC's success rate, owing to its contribution to reducing secondary cesarean section.


Assuntos
Cesárea , Nomogramas , Nascimento Vaginal Após Cesárea/estatística & dados numéricos , Adulto , China , Feminino , Humanos , Gravidez , Estudos Retrospectivos
11.
Sci Rep ; 9(1): 16922, 2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31729427

RESUMO

AXL is expressed in many types of cancer and promotes cancer cell survival, metastasis and drug resistance. Here, we focus on identifying modulators that regulate AXL at the mRNA level. We have previously observed that the AXL promoter activity is inversely correlated with the AXL expression levels, suggesting that post-transcriptional mechanisms exist that down-regulate the expression of AXL mRNA. Here we show that the RNA binding protein PTBP1 (polypyrimidine tract-binding protein) directly targets the 5'-UTR of AXL mRNA in vitro and in vivo. Moreover, we also demonstrate that PTBP1, but not PTBP2, inhibits the expression of AXL mRNA and the RNA recognition motif 1 (RRM1) of PTBP1 is crucial for this interaction. To clarify how PTBP1 regulates AXL expression at the mRNA level, we found that, while the transcription rate of AXL was not significantly different, PTBP1 decreased the stability of AXL mRNA. In addition, over-expression of AXL may counteract the PTBP1-mediated apoptosis. Knock-down of PTBP1 expression could enhance tumor growth in animal models. Finally, PTBP1 was found to be negatively correlated with AXL expression in lung tumor tissues in Oncomine datasets and in tissue micro-array (TMA) analysis. In conclusion, we have identified a molecular mechanism of AXL expression regulation by PTBP1 through controlling the AXL mRNA stability. These findings may represent new thoughts alternative to current approaches that directly inhibit AXL signaling and may eventually help to develop novel therapeutics to avoid cancer metastasis and drug resistance.


Assuntos
Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Regulação da Expressão Gênica , Ribonucleoproteínas Nucleares Heterogêneas/metabolismo , Proteína de Ligação a Regiões Ricas em Polipirimidinas/metabolismo , Proteínas Proto-Oncogênicas/genética , Estabilidade de RNA , RNA Mensageiro/genética , Receptores Proteína Tirosina Quinases/genética , Regiões 5' não Traduzidas , Apoptose , Linhagem Celular Tumoral , Movimento Celular , Sobrevivência Celular , Expressão Gênica , Genes Reporter , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Receptor Tirosina Quinase Axl
12.
Nucleus ; 10(1): 126-143, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31142202

RESUMO

The double membrane nuclear envelope (NE), which is contiguous with the ER, contains nuclear pore complexes (NPCs) - the channels for nucleocytoplasmic transport, and the nuclear lamina (NL) - a scaffold for NE and chromatin organization. Since numerous human diseases linked to NE proteins occur in mesenchyme-derived cells, we used proteomics to characterize NE and other subcellular fractions isolated from mesenchymal stem cells and from adipocytes and myocytes. Based on spectral abundance, we calculated enrichment scores for proteins in the NE fractions. We demonstrated by quantitative immunofluorescence microscopy that five little-characterized proteins with high enrichment scores are substantially concentrated at the NE, with Itprip exposed at the outer nuclear membrane, Smpd4 enriched at the NPC, and Mfsd10, Tmx4, and Arl6ip6 likely residing in the inner nuclear membrane. These proteins provide new focal points for studying the functions of the NE. Moreover, our datasets provide a resource for evaluating additional potential NE proteins.


Assuntos
Proteínas de Membrana/análise , Células-Tronco Mesenquimais/química , Membrana Nuclear/química , Organelas/química , Proteômica , Células Cultivadas , Células HEK293 , Humanos , Células-Tronco Mesenquimais/metabolismo , Membrana Nuclear/metabolismo , Organelas/metabolismo
13.
J Biomed Sci ; 25(1): 80, 2018 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-30419905

RESUMO

BACKGROUND: TNS2 is a focal adhesions protein and a binding partner for many proteins, including the receptor tyrosine kinase Axl. Although TNS2 can bind with Axl, the details of their interactions have not been elucidated. TNS2 is involved in IRS-1 signaling pathway. In this study, we confirmed the relationship between TNS2 expression and the expression of Axl, IRS-1, PDK1 and Glut4 in pancreatic cancer patients. METHODS: The expression levels of TNS2, Axl, IRS-1, PDK1 and Glut4 in human cancer cells were measured by Western blot and/or IP-Western blot assays. Paired samples of pancreatic cancer and non-cancer tissues were obtained from 33 patients and were used to construct tissue microarrays. The expression levels of these markers in the tissue microarrays were measured by enzyme-linked Immunohistochemistry assay, and the relationships were analyzed by Pearson's chi-square test and two-tailed t-test analysis. RESULTS: We demonstrated for the first time that TNS2 is a phosphorylation substrate of Axl. Moreover, we found a positive relationship between TNS2 expression and the expression of Axl, IRS-1, PDK1 and Glut4 in pancreatic cancer patients. Based on these results, we suggest that Axl modulates glucose metabolism potentially through TNS2 and IRS-1. We hypothesize that there exists a novel mechanism whereby Axl binds to and phosphorylates TNS2, releasing TNS2 from interaction with IRS-1 and resulting in increased stability of IRS-1. The two key enzymes of aerobic glycolysis (Glut4 and PDK1) were found to be up-regulated by Axl/TNS2/IRS-1 cross-talk and may play a critical role in glucose metabolism of cancer cells. CONCLUSIONS: Our results revealed for the first time that Axl binds to and phosphorylates TNS2 and that Axl/TNS2/IRS-1 cross-talk may potentially play a critical role in glucose metabolism of cancer cells.


Assuntos
Regulação Neoplásica da Expressão Gênica , Proteínas Substratos do Receptor de Insulina/genética , Proteínas Proto-Oncogênicas/genética , Receptores Proteína Tirosina Quinases/genética , Tensinas/genética , Linhagem Celular Tumoral , Células HEK293 , Humanos , Proteínas Substratos do Receptor de Insulina/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Tensinas/metabolismo , Regulação para Cima , Receptor Tirosina Quinase Axl
14.
Methods Mol Biol ; 1774: 423-434, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29916168

RESUMO

Detection of cell proliferation based on the incorporation of 5'-bromo-2'-deoxyuridine (BrdU) has become a standard approach for studying stem cell and progenitor cell populations in developing and adult tissue. In this chapter, we describe three BrdU administration methods for planarians and a staining protocol combining BrdU detection with whole-mount fluorescence in situ hybridization (FISH). Collectively, these protocols enable the combined analysis of BrdU-incorporation and endogenous gene expression, as for example during lineage tracing applications.


Assuntos
Bromodesoxiuridina/química , Planárias/genética , Animais , Proliferação de Células/genética , Expressão Gênica/genética , Hibridização in Situ Fluorescente/métodos
15.
Cell ; 173(7): 1593-1608.e20, 2018 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-29906446

RESUMO

Proliferating cells known as neoblasts include pluripotent stem cells (PSCs) that sustain tissue homeostasis and regeneration of lost body parts in planarians. However, the lack of markers to prospectively identify and isolate these adult PSCs has significantly hampered their characterization. We used single-cell RNA sequencing (scRNA-seq) and single-cell transplantation to address this long-standing issue. Large-scale scRNA-seq of sorted neoblasts unveiled a novel subtype of neoblast (Nb2) characterized by high levels of PIWI-1 mRNA and protein and marked by a conserved cell-surface protein-coding gene, tetraspanin 1 (tspan-1). tspan-1-positive cells survived sub-lethal irradiation, underwent clonal expansion to repopulate whole animals, and when purified with an anti-TSPAN-1 antibody, rescued the viability of lethally irradiated animals after single-cell transplantation. The first prospective isolation of an adult PSC bridges a conceptual dichotomy between functionally and molecularly defined neoblasts, shedding light on mechanisms governing in vivo pluripotency and a source of regeneration in animals. VIDEO ABSTRACT.


Assuntos
Proteínas Argonautas/metabolismo , Proteínas de Helminto/metabolismo , Planárias/fisiologia , Tetraspaninas/metabolismo , Animais , Proteínas Argonautas/antagonistas & inibidores , Proteínas Argonautas/genética , Ciclo Celular/efeitos da radiação , Regulação da Expressão Gênica , Proteínas de Helminto/antagonistas & inibidores , Proteínas de Helminto/genética , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/metabolismo , Células-Tronco Pluripotentes/transplante , Análise de Componente Principal , Interferência de RNA , RNA de Cadeia Dupla/metabolismo , RNA de Helmintos/química , RNA de Helmintos/isolamento & purificação , RNA de Helmintos/metabolismo , Regeneração/genética , Análise de Sequência de RNA , Análise de Célula Única , Tetraspaninas/genética , Irradiação Corporal Total
16.
Dev Biol ; 433(2): 357-373, 2018 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-29100657

RESUMO

The epidermis is essential for animal survival, providing both a protective barrier and cellular sensor to external environments. The generally conserved embryonic origin of the epidermis, but the broad morphological and functional diversity of this organ across animals is puzzling. We define the transcriptional regulators underlying epidermal lineage differentiation in the planarian Schmidtea mediterranea, an invertebrate organism that, unlike fruitflies and nematodes, continuously replaces its epidermal cells. We find that Smed-p53, Sox and Pax transcription factors are essential regulators of epidermal homeostasis, and act cooperatively to regulate genes associated with early epidermal precursor cell differentiation, including a tandemly arrayed novel gene family (prog) of secreted proteins. Additionally, we report on the discovery of distinct and previously undescribed secreted organelles whose production is dependent on the transcriptional activity of soxP-3, and which we term Hyman vesicles.


Assuntos
Células Epidérmicas , Proteínas de Helminto/fisiologia , Planárias/citologia , Estruturas Animais/ultraestrutura , Animais , Anticorpos Anti-Helmínticos/imunologia , Diferenciação Celular/genética , Linhagem da Célula , Movimento Celular , Epiderme/metabolismo , Epiderme/efeitos da radiação , Epiderme/ultraestrutura , Regulação da Expressão Gênica no Desenvolvimento , Ontologia Genética , Genes de Helmintos , Proteínas de Helminto/genética , Proteínas de Helminto/imunologia , Mesoderma/citologia , Microscopia Eletrônica , Família Multigênica , Organelas/ultraestrutura , Planárias/metabolismo , Planárias/ultraestrutura , Interferência de RNA , Fatores de Transcrição/fisiologia
17.
Artigo em Inglês | MEDLINE | ID: mdl-28630657

RESUMO

Adenosine diphosphate (ADP)-ribosylation factor-like tumour suppressor gene 1(ARLTS1) might be associated with an increased risk of several types of familial cancers. However, previous studies have shown that cancer susceptibility is not completely consistent with ARLTS1 polymorphisms, and the precise mechanism remains unknown. Therefore, we conducted a meta-analysis of case-control studies by searching the PubMed, Embase, OVID, Science Direct and Chinese National Knowledge Infrastructure (CNKI) databases. In total, 12 studies met the inclusion criteria and were included in this meta-analysis. Statistical analyses were performed using STATA 11.0 software. Overall, the Cys148Arg T > C variant significantly increased cancer risk (CC vs. TT: OR = 1.27, 95% CI = 1.15-1.41, P < 0.05). The stratification indicated that the Cys148Arg variant is significantly associated with sporadic cancer (CC vs. TT: OR = 1.36, 95% CI = 1.18-1.55) and familial cancer (CC vs. TT: OR = 1.26, 95% CI = 1.12-1.43). Trp149Stop, Pro131Leu, Ser99Ser and Leu132Leu were not correlated with cancer susceptibility. Based on these results, we demonstrated that the ARLTS1 Cys148Arg polymorphism is associated with an increased risk of sporadic cancer and familial cancer, and there were no associations between the other four SNPs (i.e., Trp149Stop, Pro131Leu, Ser99Ser and Leu132Leu) and cancer risk.

18.
Oncotarget ; 8(2): 3315-3326, 2017 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-27926514

RESUMO

In order to decrease the toxicity of paclitaxel (PTX) and increase the efficiency, we developed an amphiphilic PTX injection system using a biodegradable and biocompatible polymer synthesized by folic acid, cholesterol, and chitosan (FACC). This FACC-based polymer had a low critical concentration (64.13µg/ml) and could self-assemble in aqueous condition to form nanoscale micelles. The particle sizes of FACC-PTX micelles were 253.2±0.56 nm, the encapsulation efficiency and loading capacity of these FACC-PTX micelles were 65.1±0.23% and 9.1±0.16%, respectively. The cumulative release rate was about 85% at pH 5.0 which was higher than that at pH 7.4 (76%). This pH-dependent release behavior was highly suggesting that PTX release from FACC-PTX micelles might be higher in a weak acidic tumor microenvironment and lower toxic for normal cells. The anti-cancer effectiveness of FACC-PTX micelles was investigated by in vitro cytotoxicity and targeting study. The results revealed that FACC micelles have non-toxic on cells as evidenced by high cell viability found (86% to 100%) in the cells cultured with various concentrations of FACC micelles (1 to 500 µg/ml). Targeting study indicated that the cytotoxic efficacy of FACC-PTX micelles was significantly higher than that with Taxol® in the Hela cells (folate receptor-positive cells). These findings indicated that the anticancer efficiency of PTX can be enhanced by adding some cancer cell positive receptor into drug carrier and the FACC micelle was a potential tumor targeting carrier for PXT delivery.


Assuntos
Antineoplásicos Fitogênicos/administração & dosagem , Quitosana , Colesterol , Ácido Fólico , Micelas , Paclitaxel/administração & dosagem , Antineoplásicos Fitogênicos/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Quitosana/química , Colesterol/química , Liberação Controlada de Fármacos , Ácido Fólico/química , Humanos , Concentração de Íons de Hidrogênio , Paclitaxel/química , Tamanho da Partícula , Espectroscopia de Prótons por Ressonância Magnética
19.
Elife ; 4: e10501, 2015 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-26457503

RESUMO

Neoblasts are an abundant, heterogeneous population of adult stem cells (ASCs) that facilitate the maintenance of planarian tissues and organs, providing a powerful system to study ASC self-renewal and differentiation dynamics. It is unknown how the collective output of neoblasts transit through differentiation pathways to produce specific cell types. The planarian epidermis is a simple tissue that undergoes rapid turnover. We found that as epidermal progeny differentiate, they progress through multiple spatiotemporal transition states with distinct gene expression profiles. We also identified a conserved early growth response family transcription factor, egr-5, that is essential for epidermal differentiation. Disruption of epidermal integrity by egr-5 RNAi triggers a global stress response that induces the proliferation of neoblasts and the concomitant expansion of not only epidermal, but also multiple progenitor cell populations. Our results further establish the planarian epidermis as a novel paradigm to uncover the molecular mechanisms regulating ASC specification in vivo.


Assuntos
Células-Tronco Adultas/fisiologia , Diferenciação Celular , Fatores de Transcrição de Resposta de Crescimento Precoce/metabolismo , Células Epiteliais/fisiologia , Animais , Fatores de Transcrição de Resposta de Crescimento Precoce/antagonistas & inibidores , Fatores de Transcrição de Resposta de Crescimento Precoce/genética , Epiderme/fisiologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Inativação Gênica , Planárias
20.
J Air Waste Manag Assoc ; 63(10): 1182-9, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24282970

RESUMO

This study investigates how reducing additives governed the vitrification of prepared specimens. In the experiments, pure CaO/CaCO3 and SiO2 served as the major components of glassy matrix (basicity = mass ratio of CaO/SiO2 = 2/3) with doping of hazardous metals (Cr Cu, and Ni). The substitution ratio of CaCO3 for CaO was used as an operating parameter. The specimens were vitrified at 1400 degrees C and a sequential extraction protocol was used to determine the phase distribution of Cr, Cu, and Ni. The volume fractions of crystalline and amorphous phases were measured using semiquantitative x-ray diffraction (XRD) analysis. A commercial software package (HSC Chemistry 6.0) was used to simulate the experiment to acquire additional information. The simulation results showed the addition of CaCO3 generated CO and CO2 at high temperature. This reducing atmosphere might enhance Cu and Ni to be easily separated from slags and elevated the levels of Cu and Ni in ingots. At higher CaCO3 mol(%), the polymerization of silicate (from sorosilicate to inosilicate) in slag rose and the CaSiO3 amount increased. In addition, the immobilization of metals and the acid resistance of slags were improved. The results indicate that CaCO3 addition is favorable for increasing the metal level in ingots and the metal encapsulation in slag in vitrification.


Assuntos
Resíduos Perigosos/análise , Eliminação de Resíduos/métodos , Simulação por Computador , Modelos Teóricos , Vitrificação
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