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1.
Cell ; 173(3): 624-633.e8, 2018 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-29656892

RESUMO

CTLA-4 immune checkpoint blockade is clinically effective in a subset of patients with metastatic melanoma. We identify a subcluster of MAGE-A cancer-germline antigens, located within a narrow 75 kb region of chromosome Xq28, that predicts resistance uniquely to blockade of CTLA-4, but not PD-1. We validate this gene expression signature in an independent anti-CTLA-4-treated cohort and show its specificity to the CTLA-4 pathway with two independent anti-PD-1-treated cohorts. Autophagy, a process critical for optimal anti-cancer immunity, has previously been shown to be suppressed by the MAGE-TRIM28 ubiquitin ligase in vitro. We now show that the expression of the key autophagosome component LC3B and other activators of autophagy are negatively associated with MAGE-A protein levels in human melanomas, including samples from patients with resistance to CTLA-4 blockade. Our findings implicate autophagy suppression in resistance to CTLA-4 blockade in melanoma, suggesting exploitation of autophagy induction for potential therapeutic synergy with CTLA-4 inhibitors.


Assuntos
Antígeno CTLA-4/genética , Antígeno CTLA-4/imunologia , Epigênese Genética , Mutação em Linhagem Germinativa , Neoplasias/genética , Neoplasias/imunologia , Animais , Anticorpos Monoclonais/uso terapêutico , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/imunologia , Autofagia , Linhagem Celular Tumoral , Metilação de DNA , Feminino , Perfilação da Expressão Gênica , Humanos , Imunoterapia , Ipilimumab/farmacologia , Masculino , Melanoma/genética , Melanoma/imunologia , Antígenos Específicos de Melanoma/genética , Antígenos Específicos de Melanoma/imunologia , Camundongos , Camundongos Transgênicos , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/imunologia
2.
Cell ; 162(6): 1242-56, 2015 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-26359984

RESUMO

Therapeutic antibodies targeting programmed cell death 1 (PD-1) activate tumor-specific immunity and have shown remarkable efficacy in the treatment of melanoma. Yet, little is known about tumor cell-intrinsic PD-1 pathway effects. Here, we show that murine and human melanomas contain PD-1-expressing cancer subpopulations and demonstrate that melanoma cell-intrinsic PD-1 promotes tumorigenesis, even in mice lacking adaptive immunity. PD-1 inhibition on melanoma cells by RNAi, blocking antibodies, or mutagenesis of melanoma-PD-1 signaling motifs suppresses tumor growth in immunocompetent, immunocompromised, and PD-1-deficient tumor graft recipient mice. Conversely, melanoma-specific PD-1 overexpression enhances tumorigenicity, as does engagement of melanoma-PD-1 by its ligand, PD-L1, whereas melanoma-PD-L1 inhibition or knockout of host-PD-L1 attenuate growth of PD-1-positive melanomas. Mechanistically, the melanoma-PD-1 receptor modulates downstream effectors of mTOR signaling. Our results identify melanoma cell-intrinsic functions of the PD-1:PD-L1 axis in tumor growth and suggest that blocking melanoma-PD-1 might contribute to the striking clinical efficacy of anti-PD-1 therapy.


Assuntos
Melanoma/genética , Receptor de Morte Celular Programada 1/metabolismo , Transdução de Sinais , Animais , Antineoplásicos/administração & dosagem , Antígeno B7-H1/genética , Linhagem Celular Tumoral , Células Cultivadas , Técnicas de Silenciamento de Genes , Xenoenxertos , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Transplante de Neoplasias
3.
Cell ; 150(6): 1135-46, 2012 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-22980977

RESUMO

DNA methylation at the 5 position of cytosine (5-mC) is a key epigenetic mark that is critical for various biological and pathological processes. 5-mC can be converted to 5-hydroxymethylcytosine (5-hmC) by the ten-eleven translocation (TET) family of DNA hydroxylases. Here, we report that "loss of 5-hmC" is an epigenetic hallmark of melanoma, with diagnostic and prognostic implications. Genome-wide mapping of 5-hmC reveals loss of the 5-hmC landscape in the melanoma epigenome. We show that downregulation of isocitrate dehydrogenase 2 (IDH2) and TET family enzymes is likely one of the mechanisms underlying 5-hmC loss in melanoma. Rebuilding the 5-hmC landscape in melanoma cells by reintroducing active TET2 or IDH2 suppresses melanoma growth and increases tumor-free survival in animal models. Thus, our study reveals a critical function of 5-hmC in melanoma development and directly links the IDH and TET activity-dependent epigenetic pathway to 5-hmC-mediated suppression of melanoma progression, suggesting a new strategy for epigenetic cancer therapy.


Assuntos
Citosina/análogos & derivados , Epigênese Genética , Regulação Neoplásica da Expressão Gênica , Melanoma/genética , Nevo/genética , 5-Metilcitosina/análogos & derivados , Citosina/metabolismo , Proteínas de Ligação a DNA/genética , Dioxigenases , Estudo de Associação Genômica Ampla , Humanos , Isocitrato Desidrogenase/genética , Melanócitos/metabolismo , Melanoma/patologia , Nevo/patologia , Proteínas Proto-Oncogênicas/genética
4.
J Intern Med ; 295(5): 634-650, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38439117

RESUMO

BACKGROUND: The immune reconstitution after allogeneic hematopoietic stem cell transplantation (allo-HSCT) is crucial for preventing infections and relapse and enhancing graft-versus-tumor effects. B cells play an important role in humoral immunity and immune regulation, but their reconstitution after allo-HSCT has not been well studied. METHODS: In this study, we analyzed the dynamics of B cells in 252 patients who underwent allo-HSCT for 2 years and assessed the impact of factors on B-cell reconstitution and their correlations with survival outcomes, as well as the development stages of B cells in the bone marrow and the subsets in the peripheral blood. RESULTS: We found that the B-cell reconstitution in the bone marrow was consistent with the peripheral blood (p = 0.232). B-cell reconstitution was delayed by the male gender, age >50, older donor age, the occurrence of chronic and acute graft-versus-host disease, and the infections of fungi and cytomegalovirus. The survival analysis revealed that patients with lower B cells had higher risks of death and relapse. More importantly, we used propensity score matching to obtain the conclusion that post-1-year B-cell reconstitution is better in females. Meanwhile, using mediation analysis, we proposed the age-B cells-survival axis and found that B-cell reconstitution at month 12 posttransplant mediated the effect of age on patient survival (p = 0.013). We also found that younger patients showed more immature B cells in the bone marrow after transplantation (p = 0.037). CONCLUSION: Our findings provide valuable insights for optimizing the management of B-cell reconstitution and improving the efficacy and safety of allo-HSCT.


Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Feminino , Humanos , Masculino , Transplante Homólogo , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Doença Enxerto-Hospedeiro/etiologia , Doença Enxerto-Hospedeiro/prevenção & controle , Doença Enxerto-Hospedeiro/epidemiologia , Linfócitos B , Recidiva
5.
Nephrol Dial Transplant ; 39(3): 520-530, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-37667508

RESUMO

BACKGROUND: The 2021 clinical guidelines of the Kidney Disease: Improving Global Outcomes emphasize the importance of the histological activity index (AI) in the management of lupus nephritis (LN). Patients with LN and a high AI have poor renal outcomes and high rates of nephritic relapse. In this study we constructed prediction models for the AI in LN. METHODS: The study population comprised 337 patients diagnosed with LN using kidney biopsy. The participants were randomly divided into training and testing cohorts. They were further divided into high-activity (AI >2) and low-activity (AI ≤2) groups. This study developed two clinical prediction models using logistic regression and least absolute shrinkage and selection operator (LASSO) analyses with laboratory test results collected at the time of kidney biopsy. The performance of models was assessed using 5-fold cross-validation and validated in the testing cohort. A nomogram for individual assessment was constructed based on the preferable model. RESULTS: Multivariate analysis showed that higher mean arterial pressure, lower estimated glomerular filtration rate, lower complement 3 level, higher urinary erythrocytes count and anti-double-stranded DNA seropositivity were independent risk factors for high histologic activity in LN. Both models performed well in the testing cohort regarding the discriminatory ability to identify patients with an AI >2. The average area under the curve of 5-fold cross-validation was 0.855 in the logistic model and 0.896 in the LASSO model. A webtool based on the LASSO model was created for clinicians to enter baseline clinical parameters to produce a probability score of an AI >2. CONCLUSIONS: The established nomogram provides a quantitative auxiliary tool for distinguishing LN patients with a high AI and helps physicians make clinical decisions in their comprehensive assessment.


Assuntos
Nefrite Lúpica , Humanos , Nefrite Lúpica/diagnóstico , Nefrite Lúpica/patologia , Nomogramas , Rim/patologia , Taxa de Filtração Glomerular , Projetos de Pesquisa
6.
Angew Chem Int Ed Engl ; 62(42): e202311387, 2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37650244

RESUMO

Diradicals based on the Blatter units and connected by acetylene and alkene spacers have been prepared. All the molecules show sizably large diradical character and low energy singlet-triplet gaps. Their photo-physical properties concerning their lowest energy excited state have been studied in detail by steady-state and time-resolved absorption spectroscopy. We have fully identified the main optical absorption band and full absence of emission from the lowest energy excited state. A computational study has been also carried out that has helped to identify the presence of a conical intersection between the lowest energy excited state and the ground state which produces a highly efficient light-to-heat conversion of the absorbed radiation. Furthermore, an outstanding photo-thermal conversion 77.23 % has been confirmed, close to the highest in the diradicaloid field. For the first time, stable diradicals are applied to photo-thermal therapy of tumor cells with good stability and satisfactory performance at near-infrared region.

7.
BMC Cancer ; 22(1): 649, 2022 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-35698045

RESUMO

BACKGROUND: Prognosis for patients recurred rapidly after resection of pancreatic ductal adenocarcinoma (PDAC) was extremely poor. We proposed the concept of postoperative hyper-progression disease (PO-HPD) to define recurrence within 2 months after surgery, explored the role of surgery for postoperative HPD patients and determined the predictive preoperative risk factors and genomic features of PO-HPD. METHODS: 976 patients undergoing curative resection of PDAC were enrolled. Survival data of 1733 stage IV patients from the US Surveillance, Epidemiology and End Results database was also collected. Patients relapsed were grouped into 3 groups regarding of the recurrence time (within 2 months were PO-HPD, within 2 to 12 months were early recurrence (ER) and within > 12 months were late recurrence (LR)). Risk factors for PO-HPD were explored with logistic regression models. Genomic features of 113 patients were investigated using next-generation sequencing-based gene panel testing. RESULTS: 718 of 976 cases relapsed, 101were PO-HPD, 418 were ER and 199 were LR. Total survival of PO-HPD was 12.5 months, shorter than that of ER (16.7 months) and LR (35.1 months), and verged on that of stage IV patients (10.6 months). Preoperative risk factors for PO-HPD included red blood cell count < 3.94*10^12/L, CA19-9 ≥ 288.6 U/mL, CA125 ≥ 22.3 U/mL and tumor size≥3.45 cm. Mutations of CEBPA, ATR and JAK1 were only identified in PO-HPD and they owned lower level of CN gain compared to others. CONCLUSIONS: Prognosis of PO-HPD was extremely poor and the role of surgery for PO-HPD should be prudently assessed.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/cirurgia , Humanos , Recidiva Local de Neoplasia/epidemiologia , Recidiva Local de Neoplasia/genética , Pancreatectomia/métodos , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/cirurgia , Prognóstico , Estudos Retrospectivos , Neoplasias Pancreáticas
8.
Neurosurg Rev ; 45(4): 2909-2918, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35589870

RESUMO

Seizures are the second most common manifestations of brain arteriovenous malformations (bAVMs). This study was conducted to investigate the clinical and angioarchitectural features of bAVMs with seizures and provide guidelines for the clinical management of these patients. We collected clinical and radiological data on patients with bAVMs diagnosed by digital subtraction angiography between January 2013 and December 2020 and dichotomized the patients into the seizures and non-seizures groups. We identified differences in demographic and angiographic features. Logistic regression and random forest (RF) models were developed and compared. The diagnostic capacity was assessed using receiver operating characteristic (ROC) curves. A nomogram was constructed, and the clinical impact was determined by decision curve analysis. A total of 414 patients with bAVMs were included in the analysis, of which 78 (18.8%) had bAVM-related seizures. In the multivariable logistic regression model, the location and side of bAVMs were independently associated with seizures. In RF models, the maximal diameter of veins and the cross-sectional area of feeding arteries and draining veins were the most important features. ROC curves showed that the RF model was not better than MLR in predicting seizures. Decision curve analysis revealed that the use of a constructed nomogram to stratify the seizure patients was beneficial at all threshold probabilities in our study. The side and location of bAVMs are specific angioarchitectural features independently associated with the occurrences of seizures with bAVMs.


Assuntos
Malformações Arteriovenosas Intracranianas , Angiografia Digital , Encéfalo , Humanos , Malformações Arteriovenosas Intracranianas/complicações , Malformações Arteriovenosas Intracranianas/diagnóstico por imagem , Curva ROC , Estudos Retrospectivos
9.
Proc Natl Acad Sci U S A ; 116(46): 23264-23273, 2019 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-31662475

RESUMO

Glycolytic enzyme phosphoglycerate mutase 1 (PGAM1) plays a critical role in cancer metabolism by coordinating glycolysis and biosynthesis. A well-validated PGAM1 inhibitor, however, has not been reported for treating pancreatic ductal adenocarcinoma (PDAC), which is one of the deadliest malignancies worldwide. By uncovering the elevated PGAM1 expressions were statistically related to worse prognosis of PDAC in a cohort of 50 patients, we developed a series of allosteric PGAM1 inhibitors by structure-guided optimization. The compound KH3 significantly suppressed proliferation of various PDAC cells by down-regulating the levels of glycolysis and mitochondrial respiration in correlation with PGAM1 expression. Similar to PGAM1 depletion, KH3 dramatically hampered the canonic pathways highly involved in cancer metabolism and development. Additionally, we observed the shared expression profiles of several signature pathways at 12 h after treatment in multiple PDAC primary cells of which the matched patient-derived xenograft (PDX) models responded similarly to KH3 in the 2 wk treatment. The better responses to KH3 in PDXs were associated with higher expression of PGAM1 and longer/stronger suppressions of cancer metabolic pathways. Taken together, our findings demonstrate a strategy of targeting cancer metabolism by PGAM1 inhibition in PDAC. Also, this work provided "proof of concept" for the potential application of metabolic treatment in clinical practice.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma Ductal Pancreático/tratamento farmacológico , Neoplasias Pancreáticas/tratamento farmacológico , Fosfoglicerato Mutase/antagonistas & inibidores , Regulação Alostérica , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Camundongos Nus , Camundongos SCID , Estrutura Molecular , Terapia de Alvo Molecular , Transplante de Neoplasias , Distribuição Aleatória , Transdução de Sinais/efeitos dos fármacos
10.
Genomics ; 113(2): 827-842, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33515675

RESUMO

O-GlcNAcylation is important in the development and progression of pancreatic ductal adenocarcinoma (PDAC). The glycosyltransferase EGF domain-specific O-linked GlcNAc transferase (EOGT) acts as a key participant in glycosylating NOTCH1. High-throughput sequencing of specimens from 30 advanced PDAC patients identified SHCBP1 and EOGT as factors of poor prognosis. We hypothesized that they could mediate PDAC progression by influencing NOTCH1 O-GlcNAcylation. Thus, 186 PDAC tissue specimens were immunostained for EOGT and SHCBP1. Pancreatic cancer cell lines and nude mouse models were used for in vitro and in vivo experiments. Respectively, The protein expression of EOGT and SHCBP1 was significantly elevated and correlated with worse prognosis in PDAC patients. In vitro, SHCBP1 overexpression promoted pancreatic cancer cell proliferation, migration and invasion, while knocking down SHCBP1 and EOGT inhibited these malignant processes. In vivo data showed that SHCBP1 overexpression promoted xenograft growth and lung metastasis and shortened survival in mice, whereas knocking down either EOGT or SHCBP1 expression suppressed xenograft growth and metastasis and prolonged survival. We further clarified the molecular mechanisms by which EOGT and SHCBP1 enhance the O-GlcNAcylation of NOTCH1, Subsequently promoting the nuclear localization of the Notch intracellular domain (NICD) and inhibiting the transcription of E-cadherin and P21 in pancreatic cancer cells.


Assuntos
N-Acetilglucosaminiltransferases/metabolismo , Neoplasias Pancreáticas/metabolismo , Receptor Notch1/metabolismo , Proteínas Adaptadoras da Sinalização Shc/metabolismo , Acetilação , Acetilglucosamina/metabolismo , Animais , Linhagem Celular Tumoral , Feminino , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , N-Acetilglucosaminiltransferases/genética , Metástase Neoplásica , Neoplasias Pancreáticas/patologia , Ligação Proteica , Proteínas Adaptadoras da Sinalização Shc/genética
11.
Molecules ; 27(20)2022 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-36296429

RESUMO

Two famous topological indices, the Gutman index and Schultz index, are studied in this article. We mainly calculate the exact analytical formulae for the expected values of the Gutman index and Schultz index of a random regular polygonal chain with n regular polygons. Moreover, we determine the average values and the extremal values of the indices in regard to the set of all these regular polygonal chains.

12.
J Magn Reson Imaging ; 53(3): 953-962, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33034113

RESUMO

BACKGROUND: The progression of atherosclerotic plaque is a dynamic process; however, the natural evolution process of plaque enhancement on MRI remains unclear. PURPOSE: To evaluate changes in enhancement characteristics of middle cerebral arterial (MCA) atherosclerotic plaques over time using MRI and to explore the relationship between the changes in plaque enhancement and stroke recurrence. STUDY TYPE: Prospective. POPULATION: Fifty-four patients with MCA atherosclerotic plaque underwent initial and follow-up examinations with a median interval of 519 days (range 84-1820 days), including 37 males and 16 patients with recurrent stroke. FIELD STRENGTH/SEQUENCE: Time-of-flight magnetic resonance angiography, diffusion-weighted imaging, T2 -weighted imaging, pre- and postcontrast T1 -weighted imaging at 3 T. ASSESSMENT: Clinical characteristics and differences in the changes in plaque enhancement among acute, subacute and chronic stroke groups and the changes in the degree of stenosis and plaque enhancement between the patients with and without recurrent stroke were compared. Risk factors for patients with recurrent stroke were assessed. Intra- and interobserver agreement in initial and the changes in plaque enhancement and stenosis, and the correlation between changes in plaque enhancement and recurrent stroke, were evaluated. STATISTICAL TESTS: Independent-samples t-test, Mann-Whitney U-test, chi-squared test, Spearman correlation, logistic regression and Cohen's kappa test. RESULTS: There were significant differences in the changes in stenosis and plaque enhancement (P < 0.05) between the patients with and without recurrent stroke. A significant correlation was observed between the changes in plaque enhancement and stroke recurrence (r = 0.415, P < 0.05). Multivariate regression analysis showed that a change in plaque enhancement was an independent factor for stroke recurrence after adjusting for confounding factors (odds ratio [OR] = 5.797, P < 0.05). There was excellent intra- and interobserver agreement in evaluating plaque enhancement and stenosis. DATA CONCLUSION: Stable or increased enhancement of MCA plaque was related to recurrent stroke events at follow-up. Change in plaque enhancement on MRI may be an important indicator for predicting recurrent stroke. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY STAGE: 2.


Assuntos
Placa Aterosclerótica , Acidente Vascular Cerebral , Humanos , Angiografia por Ressonância Magnética , Imageamento por Ressonância Magnética , Masculino , Artéria Cerebral Média/diagnóstico por imagem , Placa Aterosclerótica/diagnóstico por imagem , Estudos Prospectivos , Acidente Vascular Cerebral/diagnóstico por imagem
13.
Microb Cell Fact ; 20(1): 213, 2021 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-34794462

RESUMO

The intestinal microecological environment is critical to an infant's growth. For those infants consuming milk power, it is very important to improve the intestinal microecological environment to promote the healthy growth of infants. In this paper, Milk protein hydrolysate (MPH), consisting of different proportions of proteins and small molecule peptides (5:5, 4:6, 3:7, 2:8, 1:9) were added to infant formula powder (IFP). The effects of MFP-enriched IFP addition on proliferation and metabolism of Bifidobacterium L80 were studied. Compared with MPH-free IFP, MFP-enriched IFP with 1:9 of proteins to small molecule peptides significantly enhanced the proliferation of Bifidobacterium L80, resulting in higher cell density, greater viable counts and higher titratable acidity. MFP-enriched IFP increased the content of seven organic acids and H2O2 in the system, and improved the antibacterial activity to E. coli BL21. This study suggested that MPH could be an effective addition to infant formula powder to promote the growth of Bifidobacterium, so to improve the intestinal health of infants.


Assuntos
Bifidobacterium/crescimento & desenvolvimento , Bifidobacterium/metabolismo , Caseínas/metabolismo , Intestinos/microbiologia , Proteínas do Leite/metabolismo , Hidrolisados de Proteína/metabolismo , Proteínas do Soro do Leite/metabolismo , Animais , Caseínas/química , Humanos , Fórmulas Infantis/química , Proteínas do Leite/química , Hidrolisados de Proteína/química , Proteínas do Soro do Leite/química
14.
J Chem Phys ; 154(20): 204302, 2021 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-34241172

RESUMO

A systematic structure and property investigation of MnGen - (n = 3-14) was conducted by means of density functional theory coupled with mass-selected anion photoelectron spectroscopy. This combined theoretical and experimental study allows global minimum and coexistence structures to be identified. It is found that the pentagonal bipyramid shape is the basic framework for the nascent growth process of MnGen - (n = 3-10), and from n = 10, the endohedral structures can be found. For n = 12, the anion MnGe12 - cluster probably includes two isomers: a major isomer with a puckered hexagonal prism geometry and a minor isomer with a distorted icosahedron geometry. Specifically, the puckered hexagonal prism isomer follows the Wade-Mingos rules and can be suggested as a new kind of superatom with the magnetic property. Furthermore, the results of adaptive natural density partitioning and deformation density analyses suggest a polar covalent interaction between Ge and Mn for endohedral clusters of MnGe12 -. The spin density and natural population analysis indicate that MnGen - clusters have high magnetic moments localized on Mn. The density of states diagram visually shows the significant spin polarization for endohedral structures and reveals the weak interaction between the Ge 4p orbital and the 4s, 3d orbitals of Mn.

15.
J Viral Hepat ; 27(11): 1138-1149, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32559002

RESUMO

Immunopathological injury induced by persistent hepatitis B virus (HBV) infection contributes to the progression from chronic hepatitis B (CHB) to hepatic cirrhosis and hepatocellular carcinoma (HCC). Regulatory T cells (Tregs), CD4+ T helper (Th) cells, and hepatic stellate cells (HSCs) are considered to be the pivotal factors during this progression. In this study, our aim was to investigate the molecular mechanisms of liver immunopathological injury associated with Tregs, CD4+ Th cells, and HSCs. Liver tissues were collected to assay the cytokines and distribution and frequencies of CD4+ Th cells and Tregs. The chemotaxis of Th17 cells towards the liver and the interactions between IL-22, IL-17A, and HSCs were explored. The data showed the frequencies of Th17 cells, and their effector molecules IL-22 and IL-17A were increased along with the severity of chronic liver diseases. However, the frequencies of Tregs were decreased in HBV-associated cirrhotic tissues compared with those in CHB tissues and HCC tissues. hepatitis B virus X antigen (HBxAg)-activated HSCs recruited more Th17 cells into the liver and conduced to the secretion of IL-17A and IL-22 that could in turn stimulate the proliferation and fibrotic marker secretion of the HSCs. Therefore, we suggest that the interactions between Th17 cells, IL-17A, IL-22, and HSCs form a positive feedback loop that aggravated the progression of chronic liver disease with HBV infection through the phosphoinositide-3-kinase/protein kinase B (PI3K/AKT) signalling pathway. Our findings indicated the IL-17A/IL-22 pathway might become a new treatment target for liver cirrhosis and HCC.


Assuntos
Carcinoma Hepatocelular , Hepatite B Crônica , Neoplasias Hepáticas , Células Estreladas do Fígado , Vírus da Hepatite B , Humanos , Fosfatidilinositol 3-Quinases , Linfócitos T Reguladores , Células Th17 , Transativadores , Proteínas Virais Reguladoras e Acessórias
16.
Nature ; 511(7509): 353-7, 2014 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-25030174

RESUMO

Corneal epithelial homeostasis and regeneration are sustained by limbal stem cells (LSCs), and LSC deficiency is a major cause of blindness worldwide. Transplantation is often the only therapeutic option available to patients with LSC deficiency. However, while transplant success depends foremost on LSC frequency within grafts, a gene allowing for prospective LSC enrichment has not been identified so far. Here we show that ATP-binding cassette, sub-family B, member 5 (ABCB5) marks LSCs and is required for LSC maintenance, corneal development and repair. Furthermore, we demonstrate that prospectively isolated human or murine ABCB5-positive LSCs possess the exclusive capacity to fully restore the cornea upon grafting to LSC-deficient mice in xenogeneic or syngeneic transplantation models. ABCB5 is preferentially expressed on label-retaining LSCs in mice and p63α-positive LSCs in humans. Consistent with these findings, ABCB5-positive LSC frequency is reduced in LSC-deficient patients. Abcb5 loss of function in Abcb5 knockout mice causes depletion of quiescent LSCs due to enhanced proliferation and apoptosis, and results in defective corneal differentiation and wound healing. Our results from gene knockout studies, LSC tracing and transplantation models, as well as phenotypic and functional analyses of human biopsy specimens, provide converging lines of evidence that ABCB5 identifies mammalian LSCs. Identification and prospective isolation of molecularly defined LSCs with essential functions in corneal development and repair has important implications for the treatment of corneal disease, particularly corneal blindness due to LSC deficiency.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Transportadores de Cassetes de Ligação de ATP/metabolismo , Limbo da Córnea/citologia , Limbo da Córnea/fisiologia , Regeneração , Células-Tronco/metabolismo , Cicatrização , Subfamília B de Transportador de Cassetes de Ligação de ATP , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/deficiência , Transportadores de Cassetes de Ligação de ATP/deficiência , Animais , Apoptose , Biomarcadores/metabolismo , Diferenciação Celular , Proliferação de Células , Feminino , Humanos , Masculino , Camundongos , Camundongos Knockout , Dados de Sequência Molecular , Transplante de Células-Tronco , Células-Tronco/citologia , Fatores de Transcrição/metabolismo , Proteínas Supressoras de Tumor/metabolismo
17.
Hepatobiliary Pancreat Dis Int ; 19(2): 163-168, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31862346

RESUMO

BACKGROUND: Previous studies presented controversies in impact of body mass index (BMI) on perioperative complications in pancreatectomy, and mainly focused on Western population. This study aimed to explore the impact of BMI on perioperative outcomes in Chinese patients undergoing pancreaticoduodenectomy. METHODS: Seven hundred and seven adult patients undergoing open pancreaticoduodenectomy between January 2005 and December 2016 at Ruijin Hospital were studied retrospectively and categorized as obese (BMI ≥25 kg/m2), overweight (BMI ≥23 kg/m2 and <25 kg/m2), or normal weight (BMI ≥18.5 kg/m2 and <23 kg/m2). Associations of these BMI groups with perioperative outcomes were evaluated. RESULTS: The overweight and obese groups experienced higher risk of clinically related postoperative pancreatic fistula (CR-POPF) (7.6% vs. 9.9% vs. 17.6%, P = 0.002) and re-operation (1.1% vs. 2.5%  vs. 5.1%, P = 0.017), and longer systemic inflammation response syndrome (SIRS) duration [2 (1-9) d vs. 2 (1-7) d vs. 3 (1-10) d, P = 0.003] and postoperative hospital stay [19 (2-84) d vs. 19 (7-158) d vs. 23 (8-121) d, P = 0.023] than the normal weight group did. The multiple logistic regression models showed obese as an independent risk factor for CR-POPF (P = 0.013). The multiple linear regression analysis confirmed BMI as a predictor for prolonged postoperative hospital stay (P = 0.005). CONCLUSIONS: Higher BMI results in higher morbidity of Chinese patients undergoing open pancreaticoduodenectomy. Pancreaticoduodenectomy is still a safe surgery procedure for overweight and obese patients, with intensive perioperative management.


Assuntos
Índice de Massa Corporal , Tempo de Internação , Obesidade/complicações , Fístula Pancreática/etiologia , Pancreaticoduodenectomia/efeitos adversos , Idoso , China , Feminino , Humanos , Peso Corporal Ideal , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Reoperação , Estudos Retrospectivos , Fatores de Risco , Síndrome de Resposta Inflamatória Sistêmica/etiologia
18.
J Cell Biochem ; 119(1): 1027-1040, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28685847

RESUMO

The study aims to verify the hypothesis that up-regulation of microRNA-300 (miR-300) targeting CUL4B promotes apoptosis and suppresses proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) of pancreatic cancer cells by regulating the Wnt/ß-catenin signaling pathway. Pancreatic cancer tissues and adjacent tissues were collected from 110 pancreatic cancer patients. Expression of miR-300, CUL4B, Wnt, ß-catenin, E-cadherin, N-cadherin, Snail, GSK-3ß, and CyclinD1 were detected using qRT-PCR and Western blot. CFPAC-1, Capan-1, and PANC-1 were classified into blank, negative control (NC), miR-300 mimics, miR-300 inhibitors, siRNA-CUL4B, and miR-300 inhibitors + siRNA-CUL4B groups. The proliferation, migration, invasion abilities, the cell cycle distribution, and apoptosis rates were measured in CCK-8 and Transwell assays. Pancreatic cancer tissues showed increased CUL4B expression but decreased miR-300 expression. When miR-300 was lowly expressed, CUL4B was upregulated which in-turn activated the Wnt/ß-catenin pathway to protect the ß-catenin expression and thus induce EMT. When miR-300 was highly expressed, CUL4B was downregulated which in-turn inhibited the Wnt/ß-catenin pathway to prevent EMT. Weakened cell migration and invasion abilities and enhanced apoptosis were observed in the CUL4B group. The miR-300 inhibitors group exhibited an evident increase in growth rate accompanied the largest tumor volume. Smaller tumor volume and slower growth rate were observed in the miR-300 mimics and siRNA-CUL4B group. Our study concludes that lowly expressed miR-300 may contribute to highly expressed CUL4B activating the Wnt/ß-catenin signaling pathway and further stimulating EMT, thus promoting proliferation and migration but suppressing apoptosis of pancreatic cancer cells.


Assuntos
Proteínas Culina/genética , Proteínas Culina/metabolismo , Transição Epitelial-Mesenquimal , MicroRNAs/genética , Neoplasias Pancreáticas/metabolismo , Idoso , Animais , Apoptose , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Camundongos , Invasividade Neoplásica , Estadiamento de Neoplasias , Transplante de Neoplasias , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Via de Sinalização Wnt
19.
BMC Med Imaging ; 18(1): 49, 2018 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-30509197

RESUMO

BACKGROUND: To compare the Self-referenced and Referenced measurement methods in assessing basilar artery (BA) atherosclerotic plaque employing dark blood high-resolution MRI at 3 Tesla. METHODS: Forty patients with > 20% stenosis as identified by conventional MRA were recruited and evaluated on a 3 Tesla MRI system. The outer wall, inner wall and lumen areas of maximal lumen narrowing site and the outer wall and lumen areas of sites that were proximal and distal to the maximal lumen narrowing site were manually traced. Plaque area (PA), stenosis rate (SR) and percent plaque burden (PPB) were calculated using the Self-referenced and Referenced measurement methods, respectively. To assess intra-observer reproducibility, BA plaque was measured twice with a 2-week interval in between measurements. RESULTS: Thirty-seven patients were included in the final analysis. There were no significant differences in PA, SR and PPB measurements between the two methods. The intra-class coefficients and coefficient of variations (CV) ranged from 0.976 to 0.990 and from 3.73 to 5.61% for the Self-referenced method and ranged from 0.928 to 0.971 and from 4.64 to 9.95% for the Referenced method, respectively. Both methods are effective in the evaluation of BA plaque. However, the CVs of the Self-referenced method is lower than the Referenced measurement method. Moreover, Bland-Altman plots showed that the Self-referenced method has a narrower interval than the Referenced measurement method. CONCLUSIONS: The Self-referenced method is better and more convenient for evaluating BA plaque, and it may serve as a promising method for evaluation of basilar atherosclerotic plaque.


Assuntos
Artéria Basilar/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Placa Aterosclerótica/diagnóstico por imagem , Idoso , Artéria Basilar/patologia , Meios de Contraste , Feminino , Humanos , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional , Angiografia por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Placa Aterosclerótica/patologia , Estudos Prospectivos
20.
Mol Cancer ; 16(1): 169, 2017 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-29121972

RESUMO

BACKGROUND: Pancreatic cancer, one of the top two most fatal cancers, is characterized by a desmoplastic reaction that creates a dense microenvironment, promoting hypoxia and inducing the epithelial-to-mesenchymal transition (EMT) to facilitate invasion and metastasis. Recent evidence indicates that the long noncoding RNA NORAD may be a potential oncogenic gene and that this lncRNA is significantly upregulated during hypoxia. However, the overall biological role and clinical significance of NORAD remains largely unknown. METHODS: NORAD expression was measured in 33 paired cancerous and noncancerous tissue samples by real-time PCR. The effects of NORAD on pancreatic cancer cells were studied by overexpression and knockdown in vitro. Insights into the mechanism of competitive endogenous RNAs (ceRNAs) were gained from bioinformatics analyses and luciferase assays. In vivo, metastatic potential was identified using an orthotopic model of PDAC and quantified using bioluminescent signals. Alterations in RhoA expression and EMT levels were identified and verified by immunohistochemistry and Western blotting. RESULTS: NORAD is highly expressed in pancreatic cancer tissues and upregulated in hypoxic conditions. NORAD upregulation is correlated with shorter overall survival in pancreatic cancer patients. Furthermore, NORAD overexpression promoted the migration and invasion of pancreatic carcinoma cells, while NORAD depletion inhibited EMT and metastasis in vitro and in vivo. In particular, NORAD may function as a ceRNA to regulate the expression of the small GTP binding protein RhoA through competition for hsa-miR-125a-3p, thereby promoting EMT. CONCLUSIONS: Elevated expression of NORAD in pancreatic cancer tissues is linked to poor prognosis and may confer a malignant phenotype upon tumor cells. NORAD may function as a ceRNA to regulate the expression of the small GTP binding protein RhoA through competition for hsa-miR-125a-3p. This finding may contribute to a better understanding of the role played by lncRNAs in hypoxia-induced EMT and provide a potential novel diagnostic and therapeutic target for pancreatic cancer.


Assuntos
MicroRNAs/genética , Neoplasias Pancreáticas/genética , RNA Longo não Codificante/genética , Regulação para Cima , Proteína rhoA de Ligação ao GTP/genética , Animais , Hipóxia Celular , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Transição Epitelial-Mesenquimal , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Camundongos , MicroRNAs/metabolismo , Invasividade Neoplásica , Transplante de Neoplasias , Neoplasias Pancreáticas/metabolismo , RNA Longo não Codificante/metabolismo
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