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1.
Breast Cancer Res ; 26(1): 94, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38844963

RESUMO

BACKGROUND: RNA m5C methylation has been extensively implicated in the occurrence and development of tumors. As the main methyltransferase, NSUN2 plays a crucial regulatory role across diverse tumor types. However, the precise impact of NSUN2-mediated m5C modification on breast cancer (BC) remains unclear. Our study aims to elucidate the molecular mechanism underlying how NSUN2 regulates the target gene HGH1 (also known as FAM203) through m5C modification, thereby promoting BC progression. Additionally, this study targets at preliminarily clarifying the biological roles of NSUN2 and HGH1 in BC. METHODS: Tumor and adjacent tissues from 5 BC patients were collected, and the m5C modification target HGH1 in BC was screened through RNA sequencing (RNA-seq) and single-base resolution m5C methylation sequencing (RNA-BisSeq). Methylation RNA immunoprecipitation-qPCR (MeRIP-qPCR) and RNA-binding protein immunoprecipitation-qPCR (RIP-qPCR) confirmed that the methylation molecules NSUN2 and YBX1 specifically recognized and bound to HGH1 through m5C modification. In addition, proteomics, co-immunoprecipitation (co-IP), and Ribosome sequencing (Ribo-Seq) were used to explore the biological role of HGH1 in BC. RESULTS: As the main m5C methylation molecule, NSUN2 is abnormally overexpressed in BC and increases the overall level of RNA m5C. Knocking down NSUN2 can inhibit BC progression in vitro or in vivo. Combined RNA-seq and RNA-BisSeq analysis identified HGH1 as a potential target of abnormal m5C modifications. We clarified the mechanism by which NSUN2 regulates HGH1 expression through m5C modification, a process that involves interactions with the YBX1 protein, which collectively impacts mRNA stability and protein synthesis. Furthermore, this study is the first to reveal the binding interaction between HGH1 and the translation elongation factor EEF2, providing a comprehensive understanding of its ability to regulate transcript translation efficiency and protein synthesis in BC cells. CONCLUSIONS: This study preliminarily clarifies the regulatory role of the NSUN2-YBX1-m5C-HGH1 axis from post-transcriptional modification to protein translation, revealing the key role of abnormal RNA m5C modification in BC and suggesting that HGH1 may be a new epigenetic biomarker and potential therapeutic target for BC.


Assuntos
Neoplasias da Mama , Progressão da Doença , Regulação Neoplásica da Expressão Gênica , Metiltransferases , Estabilidade de RNA , Proteína 1 de Ligação a Y-Box , Animais , Feminino , Humanos , Camundongos , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Metilação , Metiltransferases/metabolismo , Metiltransferases/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteína 1 de Ligação a Y-Box/metabolismo , Proteína 1 de Ligação a Y-Box/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo
2.
IEEE Trans Cybern ; 54(1): 219-229, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37027752

RESUMO

Gaze is a vital feature in analyzing natural human behavior and social interaction. Existing gaze target detection studies learn gaze from gaze orientations and scene cues via a neural network to model gaze in unconstrained scenes. Though achieve decent accuracy, these studies either employ complex model architectures or leverage additional depth information, which limits the model application. This article proposes a simple and effective gaze target detection model that employs dual regression to improve detection accuracy while maintaining low model complexity. Specifically, in the training phase, the model parameters are optimized under the supervision of coordinate labels and corresponding Gaussian-smoothed heatmap labels. In the inference phase, the model outputs the gaze target in the form of coordinates as prediction rather than heatmaps. Extensive experimental results on within-dataset and cross-dataset evaluations on public datasets and clinical data of autism screening demonstrate that our model has high accuracy and inference speed with solid generalization capabilities.


Assuntos
Sinais (Psicologia) , Fixação Ocular , Humanos , Redes Neurais de Computação , Interação Social
3.
Clin Chim Acta ; 553: 117732, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38128814

RESUMO

BACKGROUND: Detecting and identifying of clots and fibrins in serum is an important process in the analysis stage before laboratory analysis. Currently, visual examination is commonly employed in clinical laboratories for this purpose. However, this method is not only time-consuming but also highly subjective and may result in misjudgments. METHOD: A serum image blood clot and fibrin segmentation method based on improved UNeXt was proposed. The improved UNeXt segmentation network was used to train the self-built serum dataset, and the trained model was used for blood clot and fibrin segmentation in serum images. Whether the serum images contained blood clots and fibrins was identified according to the segmentation results. RESULTS: The average Dice coefficient of the serum image segmentation network output was 0.8707, which realized more accurate segmentation of blood clots and fibrins in serum images. In 13,230 clinical serum samples, the sensitivity, specificity, and accuracy of blood clot and fibrins segmentation in serum images were 95.74%, 98.11% and 97.93%, respectively, which meet clinical test requirements. CONCLUSIONS: The improved UNeXt segmentation network rapidly and accurately segmented and recognized blood clots and fibrins in serum images, which provided an accurate basis for the sampling height of the sampling needle in the automated biochemical and immunological assembly line.


Assuntos
Aprendizado Profundo , Trombose , Humanos , Fibrina , Processamento de Imagem Assistida por Computador/métodos
4.
Clin Exp Med ; 23(2): 203-218, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35066729

RESUMO

Gastric cancer (GC) is one of the most common types of tumors and the most common cause of cancer mortality worldwide. The diagnosis of GC is critical to its prevention and treatment. Available tumor markers are the crucial step for GC diagnosis. Recent studies have shown that proteins in exosomes are potential diagnostic and prognostic markers for GC. Exosomes, secreted by cells, are cup-shaped with a diameter of 30-150 nm under the electron microscope. They are also surrounded by lipid bilayers and are widely found in various body fluids. Exosomes contain proteins, lipids and nucleic acid. The examination of exosomal proteins has the advantages of quickness, easy sampling, and low pain and cost, as compared with the routine inspection method of GC, which may lead to marked developments in GC diagnosis. This article summarized the exosomal proteins with a diagnostic and prognostic potential in GC, as well as exosomal proteins involved in GC progression.


Assuntos
Exossomos , MicroRNAs , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/patologia , Prognóstico , Biomarcadores Tumorais/metabolismo , MicroRNAs/metabolismo
5.
Clin Exp Med ; 23(5): 1359-1373, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36173487

RESUMO

Tumor microenvironment (TME) consists of a dynamic network of non-tumoral stromal cells, including cancer-associated fibroblasts, endothelial cells, tumor-associated macrophages (TAMs), B and T cells. In the TME, TAMs support tumor initiation, progression, invasion and metastasis by promoting angiogenesis and immunosuppression of the tumor cells. There is close crosstalk between TAMs and tumor cells. Notably, chemokines are a significant messenger mediating the crosstalk between tumor cells and TAMs. TAMs can promote tumor progression via secretion of chemokines. Various chemokines secreted by tumors are involved in the generation and polarization of TAMs, the infiltration of TAMs in tumors, and the development of TAMs' suppressive function. This paper reviews CCL2-CCR2, CCL3/5-CCR5, CCL15-CCR1, CCL18-CCR8, CX3CL1/CCL26-CX3CR1, CXCL8-CXCR1/2, CXCL12-CXCR4/CXCR7 signaling pathways, their role in the recruitment, polarization and exertion of TAMs, and their correlation with tumor development, metastasis and prognosis. Furthermore, we present the current research progress on modulating the effects of TAMs with chemokine antagonists and discuss the prospects and potential challenges of using chemokine antagonists as therapeutic tools for cancer treatment. The TAMs targeting by chemokine receptor antagonists in combination with chemotherapy drugs, immune checkpoint inhibitors or radiotherapy appears to be a promising approach.


Assuntos
Neoplasias , Macrófagos Associados a Tumor , Humanos , Macrófagos Associados a Tumor/metabolismo , Macrófagos/metabolismo , Células Endoteliais , Neoplasias/patologia , Quimiocinas/metabolismo , Prognóstico , Microambiente Tumoral
6.
Front Oncol ; 12: 975261, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36237333

RESUMO

Metastasis is a complex process, which depends on the interaction between tumor cells and host organs. Driven by the primary tumor, the host organ will establish an environment suitable for the growth of tumor cells before their arrival, which is called the pre-metastasis niche. The formation of pre-metastasis niche requires the participation of a variety of cells, in which myeloid-derived suppressor cells play a very important role. They reach the host organ before the tumor cells, and promote the establishment of the pre-metastasis niche by influencing immunosuppression, vascular leakage, extracellular matrix remodeling, angiogenesis and so on. In this article, we introduced the formation of the pre-metastasis niche and discussed the important role of myeloid-derived suppressor cells. In addition, this paper also emphasized the targeting of myeloid-derived suppressor cells as a therapeutic strategy to inhibit the formation of pre-metastasis niche, which provided a research idea for curbing tumor metastasis.

7.
Front Immunol ; 13: 967051, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36159863

RESUMO

Background: BBIBP-CorV and CoronaVac inactivated COVID-19 vaccines are widely-used, World Health Organization-emergency-listed vaccines. Understanding antibody level changes over time after vaccination is important for booster dose policies. We evaluated neutralizing antibody (nAb) titers and associated factors for the first 12 months after primary-series vaccination with BBIBP-CorV and CoronaVac. Methods: Our study consisted of a set of cross-sectional sero-surveys in Zhejiang and Shanxi provinces, China. In 2021, we enrolled 1,527 consenting 18-59-year-olds who received two doses of BBIBP-CorV or CoronaVac 1, 3, 6, 9, or 12 months earlier and obtained blood samples and demographic and medical data. We obtained 6-month convalescent sera from 62 individuals in Hebei province. Serum nAb titers were measured by standard micro-neutralization cytopathic effect assay in Vero cells with ancestral SARS-CoV-2 strain HB01. We used the first WHO International Standard (IS) for anti-SARS-CoV-2 immunoglobulin (NIBSC code 20/136) to standardized geometric mean concentrations (IU/mL) derived from the nAb geometric mean titers (GMT over 1:4 was considered seropositive). We analyzed nAb titer trends using Chi-square and factors related to nAb titers with logistic regression and linear models. Results: Numbers of subjects in each of the five month-groupings ranged from 100 to 200 for each vaccine and met group-specific target sample sizes. Seropositivity rates from BBIBP-CorV were 98.0% at 1 month and 53.5% at 12 months, and GMTs were 25.0 and 4.0. Respective seropositivity rates from CoronaVac were 90.0% and 62.5%, and GMTs were 20.2 and 4.1. One-, three-, six-, nine-, and twelve-month GMCs were 217.2, 84.1, 85.7, 44.6, and 10.9 IU/mL in BBIBP-CorV recipients and 195.7, 94.6, 51.7, 27.6, and 13.4 IU/mL in CoronaVac recipients. Six-month convalescent seropositivity was 95.2%; GMC was 108.9 IU/mL. Seropositivity and GMCs were associated with age, sex, and time since vaccination. Conclusions: Neutralizing Ab levels against ancestral SARS-CoV-2 from BBIBP-CorV or CoronaVac vaccination were similar and decreased with increasing time since vaccination; over half of 12-month post-vaccination subjects were seropositive. Seropositivity and GMCs from BBIBP-CorV and CoronaVac six and nine months after vaccination were similar to or slightly lower than in six-month convalescent sera. These real-world data suggest necessity of six-month booster doses.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Animais , Anticorpos Neutralizantes , Anticorpos Antivirais , COVID-19/prevenção & controle , COVID-19/terapia , Chlorocebus aethiops , Estudos Transversais , Humanos , Imunização Passiva , SARS-CoV-2 , Vacinação , Células Vero , Soroterapia para COVID-19
8.
J Virol Methods ; 309: 114606, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35963582

RESUMO

Quantitative hepatitis B surface antigen assay is widely used for diagnosis of hepatitis B virus infection; however, specimens with high levels of the antigen can cause false-negative results (Hook effect), which needs to be resolved. The hook effect samples and non-hook effect samples were detected on the LiCA® 500 instrument using three methods, viz., 1, 2, and 3. Method 1, the currently used procedure, was performed in two steps with a total reaction time of 25 min in a final volume of 250 µL: first incubation was with two reagents for 15 min and then with one other reagent for 10 min. In Method 2, all three reagents were added in one step with a final volume of 250 µL, and the total reaction time was still 25 min. In Method 3, the improved method, all three reagents were added in one step while the final volume was only 130 µL and the total reaction time was only 1 min. Signal values of the non-hook effect samples obtained using Method 2 were significantly lower than those with Method 1, showing competitive inhibition. The hook effect samples tested with Method 2 approximated those obtained using Method 1. Method 3 took 1 min and differentiated hook effect samples successfully, similar to the results with Method 2 which took 25 min. Changing the timing of one reagent addition and incubation time in Method 3 provided a rapid and effective method for the identification of hook effect. The results were more clearly distinguishable due to the phenomenon of competitive inhibition. Method 3 can be considered an improvement on the chemiluminescence platform.


Assuntos
Antígenos de Superfície da Hepatite B , Hepatite B , Hepatite B/diagnóstico , Vírus da Hepatite B , Humanos , Indicadores e Reagentes , Luminescência
9.
Mol Immunol ; 145: 50-58, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35290812

RESUMO

Recently we identified the VRC01-like antibody DRVIA7(A7) from an HIV-1 B' subtype-infected individual (DRVI01) with broad neutralization activity, and almost all viruses from the individual were resistant to both VRC01 and A7 lineage antibodies. Here, we identified and characterized a panel of HIV-1 variants with resistance to VRC01 and A7 using site-directed mutagenesis and swapping amino acid fragments of gp120. Site-directed mutagenesis revealed that E279D/R282K/N460A/T464N of gp120 from DRVI01 produced VRC01-susceptible variants. Multiple mutations significantly increased the neutralization sensitivity to VRC01. Residues N464 located at the tip of the V5 loop were considered irrelevant to the neutralization of VRC01. For DRVI01-derived viruses, the single N464T change fully produced VRC01-resistant variants; conversely, a single T464N mutation generated VRC01-susceptible variants. Alanine scanning revealed that the N464 residue plays a vital role in binding with VRC01. Neutralizing assays against A7 lineage antibodies showed that DRVI01-derived viruses with multiple mutations could be neutralized by A7 lineage antibodies with different neutralizing breadths. Combining the changes in loops D and V5 produced variants that were totally sensitive variants to A7 lineage antibodies.


Assuntos
Infecções por HIV , HIV-1 , Anticorpos Monoclonais , Anticorpos Neutralizantes , Anticorpos Anti-HIV/genética , Proteína gp120 do Envelope de HIV/genética , Infecções por HIV/genética , HIV-1/genética , Humanos , Mutação/genética
10.
Drug Deliv Transl Res ; 12(10): 2385-2402, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-34973131

RESUMO

Exosomes are extracellular vesicles secreted by a variety of living cells, which have a certain degree of natural targeting as nano-carriers. Almost all exosomes released by cells will eventually enter the blood circulation or be absorbed by other cells. Under the action of content sorting mechanism, some specific surface molecules can be expressed on the surface of exosomes, such as tetraspanins protein and integrin. To some extent, these specific surface molecules can fuse with specific cells, so that exosomes show specific cell natural targeting. In recent years, exosomes have become a drug delivery system with low immunogenicity, high biocompatibility and high efficacy. Nucleic acids, polypeptides, lipids, or small molecule drugs with therapeutic function are organically loaded into exosomes, and then transported to specific types of cells or tissues in vivo, especially tumor tissues, to achieve targeting drug delivery. The natural targeting of exosome has been found and recognized in some studies, but there are still many challenges in effective clinical treatments. The use of the natural targeting of exosomes alone is incapable of accurately transporting the goods loaded to specific sites. Besides, the natural targeting of exosomes is still an open question in disease targeting and efficient gene/chemotherapy combined therapy. Engineering transformation and modification on exosomes can optimize its natural targeting and deliver the goods to a specific location, providing wide use in clinical treatment. This review summarizes the research progress of exosomal natural targeting and transformation strategy of obtained targeting after transformation. The mechanism of natural targeting and obtained targeting after transformation are also reviewed. The potential value of exosomal targeting in clinical application is also discussed.


Assuntos
Exossomos , Sistemas de Liberação de Medicamentos , Exossomos/química , Exossomos/metabolismo , Peptídeos
11.
BMC Cancer ; 21(1): 1290, 2021 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-34856955

RESUMO

BACKGROUND: RNA cargo in exosomes, especially microRNAs (miRNAs), play an important role in the chemotherapy drug resistance of human cancers. However, the role and mechanism of exosomal miR-107 on multidrug resistance of gastric cancer cells was still not clear. In this study, we sought to explore whether exosomal miR-107 could reverse the resistance of gastric cancer cells to the chemotherapy drugs. METHODS: We extracted exosomes from sensitive (SGC-7901, MGC-803) and resistant (SGC-7901/5-FU) gastric cancer cells by ultracentrifugation and the isolated exosomes were identified using transmission electron microscopy (TEM) and dynamic light scattering analysis (DLS). The expression of miR-107 and high mobility group A2 (HMGA2) were detected by real-time quantitative PCR (RT-qPCR). MTT assay was used to investigate the effect of exosomes on gastric cancer cells growth in vitro. The uptake of exosomes by recipient cells were observed using a fluorescence microscope. The predicted target relationship between miR-107 and HMGA2 was verified by gauss-luciferase reporter assay. The expression of HMGA2, p-mTOR/mTOR, P-gp and other exosomal indicated marker proteins was detected by western blot. RESULTS: Our results indicated that the isolated exosomes were typically cup-like lipid bilayer membranes structure. SGC-7901/5-FU cells were cross-resistant to chemotherapy drug cisplatin (CDDP), and the sensitive cells-secreted exosomes drastically reversed the resistance of the resistant GC cells to the chemotherapeutic drugs, which was verified by exosomal inhibitor GW4896. Mechanistically, the reversal effect was mainly mediated by exosome-secreted miR-107 through downregulating the expression of target molecular HMGA2 and inhibiting HMGA2/mTOR/P-gp pathway, which were supported by results from luciferase reporter assay and rescue assay. CONCLUSIONS: These findings demonstrated that exosome-transmitted miR-107 significantly enhanced the sensitivity of resistant gastric cancer cells to chemotherapeutic agents by mediating the HMGA2/mTOR/P-gp axis and exosomal miR-107 may be a novel target in gastric cancers treatment.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética , Exossomos/metabolismo , Proteína HMGA2/metabolismo , MicroRNAs/metabolismo , Neoplasias Gástricas/genética , Serina-Treonina Quinases TOR/metabolismo , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Cisplatino/uso terapêutico , Regulação para Baixo , Resistência a Múltiplos Medicamentos/genética , Exossomos/transplante , Exossomos/ultraestrutura , Corantes Fluorescentes , Fluoruracila/uso terapêutico , Proteína HMGA2/genética , Humanos , Microscopia Eletrônica de Transmissão , Compostos Orgânicos , Neoplasias Gástricas/tratamento farmacológico
12.
IEEE Trans Image Process ; 30: 1439-1452, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33332271

RESUMO

State-of-the-art multi-object tracking (MOT) methods follow the tracking-by-detection paradigm, where object trajectories are obtained by associating per-frame outputs of object detectors. In crowded scenes, however, detectors often fail to obtain accurate detections due to heavy occlusions and high crowd density. In this paper, we propose a new MOT paradigm, tracking-by-counting, tailored for crowded scenes. Using crowd density maps, we jointly model detection, counting, and tracking of multiple targets as a network flow program, which simultaneously finds the global optimal detections and trajectories of multiple targets over the whole video. This is in contrast to prior MOT methods that either ignore the crowd density and thus are prone to errors in crowded scenes, or rely on a suboptimal two-step process using heuristic density-aware point-tracks for matching targets. Our approach yields promising results on public benchmarks of various domains including people tracking, cell tracking, and fish tracking.

14.
Herz ; 46(3): 262-268, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32435839

RESUMO

BACKGROUND: The optimal coronary revascularization strategy for patients with unprotected left main coronary artery (ULMCA) disease and left ventricular systolic dysfunction (LVSD) remains uncertain. The purpose of this study was to evaluate the clinical outcomes after percutaneous coronary intervention (PCI) with a drug-eluting stent (DES) versus coronary artery bypass grafting (CABG) in patients with ULMCA disease with or without LVSD. METHODS: A total of 984 patients with ULMCA disease who received a DES (n = 511) or underwent CABG (n = 473) were included in this study. We retrospectively analyzed the clinical parameters and outcomes of ULMCA disease patients with different left ventricular ejection fraction levels. RESULTS: There were no significant differences in major adverse cardiac and cerebral events, all-cause death, cardiac death, myocardial infarction, or stroke between the CABG and DES groups with or without LVSD. The rate of target vessel revascularization was significantly higher with DES compared with CABG in patients without LVSD; however, the difference was not significant between the mild LVSD and severe LVSD groups. CONCLUSION: For patients with ULMCA disease and LVSD, there was no significant difference between DES and CABG in terms of efficacy and safety. Treatment with DES was an acceptable alternative to CABG.


Assuntos
Doença da Artéria Coronariana , Stents Farmacológicos , Intervenção Coronária Percutânea , Doença da Artéria Coronariana/cirurgia , Humanos , Estudos Retrospectivos , Volume Sistólico , Resultado do Tratamento , Função Ventricular Esquerda
15.
Sci Rep ; 10(1): 8056, 2020 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-32415175

RESUMO

Myeloid-derived suppressor cells (MDSCs) are a group of heterogeneous cells derived from immature myeloid cells (IMCs). MDSCs are known to play important roles in tumor immune evasion. While we know that there are a large number of circulating and tumor-infiltrating MDSCs existing in gastric cancer (GC) patients, the phenotypic characteristics and arginase 1 (ARG1) expression levels of these MDSCs remain very unclear. In our study, flow cytometric analysis of circulating MDSCs from 20 gastric adenocarcinoma (GAC) patients found that ≥80% ARG1-expressing MDSCs were mainly early-stage MDSCs (HLA-DR-CD33+CD14-CD15-MDSCs). In addition, our investigation showed that tumor-infiltrating MDSCs from 6 GAC patients consisted of >35% ARG1-expressing naïve MDSCs (HLA-DR-CD33-CD11b-CD14-CD15-MDSCs), >15% early-stage MDSCs and >40% monocytic MDSCs (HLA-DR-CD14+MDSCs). This preliminary study describes the phenotypic characteristics and ARG1 expression levels of MDSCs from GAC patients and shows that circulating and tumor-infiltrating ARG1-expressing cells were mainly immature and monocytic MDSCs, which provides information to better understand the mechanisms that allow gastric cancer cells to evade the immune system.


Assuntos
Adenocarcinoma/etiologia , Adenocarcinoma/patologia , Arginase/genética , Células Supressoras Mieloides/metabolismo , Neoplasias Gástricas/etiologia , Neoplasias Gástricas/patologia , Adenocarcinoma/metabolismo , Arginase/metabolismo , Expressão Gênica , Antígenos HLA-DR/imunologia , Antígenos HLA-DR/metabolismo , Humanos , Monócitos/imunologia , Monócitos/metabolismo , Células Supressoras Mieloides/patologia , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Neoplasias Gástricas/metabolismo , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo
16.
Int J Oncol ; 56(1): 7-17, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31789408

RESUMO

Although the majority of patients with follicular lymphoma (FL) harbor the t(14;18)(q32;q21) IGH/BCL2 gene rearrangement that leads to the overexpression of BCL2 protein, approximately 20% of FL cases lack t(14;18)(q32;q21). It is considered that BCL2 overexpression underscores the development of the majority of cases of FL and their transformation to more aggressive lymphoma [known as transformed FL (tFL)]. However, FL cases lacking the t(14;18)(q32;q21) translocation exhibit symptoms analogous to their t(14;18)­positive counterparts. An important goal of recent research on FL has been to clarify the distinctions between the two different forms of FL. Numerous studies have shed light onto the genetic and molecular features of t(14;18)­negative FL and the related clinical manifestations. In this review, we summarize the current knowledge of t(14;18)­negative FL occurring in the lymph nodes with an emphasis on the underlying molecular and clinical features. In addition, novel treatment directions are discussed.


Assuntos
Cromossomos Humanos Par 14/genética , Cromossomos Humanos Par 18/genética , Linfoma Folicular/genética , Linfoma Folicular/patologia , Translocação Genética , Humanos , Prognóstico
17.
Eur J Med Chem ; 187: 111989, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31881456

RESUMO

Lysine specific demethylase 1 (LSD1) plays an essential role in maintaining a balanced methylation status at histone tails. Overexpression of LSD1 has been involved in the development of a variety of human diseases, including cancers. Herein, on the basis of our previously developed LSD1 inhibitors, two series of new [1,2,3]triazolo[4,5-d]pyrimidine derivatives incorporating (thio)urea moiety were designed and evaluated for their LSD1 inhibitory abilities, leading to a novel chemical class of LSD1 inhibitors. Among them, compound 31 was found to moderately inhibit LSD1 activity, as well as increase the expression of H3K4me2 at the cellular level. This compound also showed good selectivity against MAO-A/-B, and a panel of kinases such as CDK and BTK. Besides, the MTT assay suggested that the selected compounds could inhibit the proliferation of LSD1-overexpressed cancer cells. Although this class of compounds only showed moderate anti-LSD1 activity in the micromolar range, this work presents a novel chemotype of LSD1 inhibitors with good enzyme selectivity as well as cellular LSD1 inhibitory activity, and could provide a useful template for the development of more potent LSD1 inhibitors for cancer treatment.


Assuntos
Antineoplásicos/farmacologia , Inibidores Enzimáticos/farmacologia , Histona Desmetilases/antagonistas & inibidores , Pirimidinas/farmacologia , Triazóis/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Histona Desmetilases/metabolismo , Humanos , Simulação de Acoplamento Molecular , Estrutura Molecular , Pirimidinas/síntese química , Pirimidinas/química , Relação Estrutura-Atividade , Triazóis/síntese química , Triazóis/química
18.
Cancer Manag Res ; 11: 4023-4040, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31190980

RESUMO

  Background: Myeloid-derived suppressor cells (MDSCs) promote immunosuppression in the tumor microenvironment, support tumor growth and survival, and may contribute to immunotherapy resistance. Recent studies showed that tumor-derived exosomes (TDEs) can induce MDSCs accumulation and expansion, the mechanisms of which are largely unknown. Methods: The morphologies and sizes of the exosomes was observed by using a JEM-1400 transmission electron microscope. MicroRNA(miR)-107 and ARG1, DICER1, PTEN, PI3K, AKT, mTOR, and NF-kB mRNAs were quantified by quantitative reverse tanscription PCR. Dual-Luciferase Reports Assay were used to examine the expression of genes which was targeted by miR-107. The expression of proteins were analyzed by using western blot. Results: MiR-107 was not only overexpressed in gastric cancer cells but also enriched in their secreted TDEs. Also, these miR-107 enriched TDEs could be taken up by HLA-DR-CD33+MDSCs, where miR-107 was able to target and suppress expression of DICER1 and PTEN genes. Dampened DICER1 expression supported expansion of MDSCs , while decreased PTEN led to activation of the PI3K pathway, resulting in increased ARG1 expression. Furthemore, gastric cancer-derived miR-107 TDEs, when dosed intravenously into mice, were also capable of inducing expansion of CD11b+Gr1+/high MDSCs in mouse peripheral blood and altering expression of DICER1, PTEN, ARG1, and NOS2 in the MDSCs. Conclusions: Our findings demonstrate for the first time that gastric cancer-secreted exosomes are able to deliver miR-107 to the host MDSCs where they induce their expansion and activition by targeting DICER1 and PTEN genes, thereby may provide novel cancer therapeutics target for gastric cancer.

19.
J Immunol ; 200(5): 1829-1838, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29367209

RESUMO

Thoracic aortic dissection (TAD), once ruptured, is devastating to patients, and no effective pharmaceutical therapy is available. Anaphylatoxins released by complement activation are involved in a variety of diseases. However, the role of the complement system in TAD is unknown. We found that plasma levels of C3a, C4a, and C5a were significantly increased in patients with TAD. Elevated circulating C3a levels were also detected in the developmental process of mouse TAD, which was induced by ß-aminopropionitrile monofumarate (BAPN) treatment, with enhanced expression of C1q and properdin in mouse dissected aortas. These findings indicated activation of classical and alternative complement pathways. Further, expression of C3aR was obviously increased in smooth muscle cells of human and mouse dissected aortas, and knockout of C3aR notably inhibited BAPN-induced formation and rupture of TAD in mice. C3aR antagonist administered pre- and post-BAPN treatment attenuated the development of TAD. We found that C3aR knockout decreased matrix metalloproteinase 2 (MMP2) expression in BAPN-treated mice. Additionally, recombinant C3a stimulation enhanced MMP2 expression and activation in smooth muscle cells that were subjected to mechanical stretch. Finally, we generated MMP2-knockdown mice by in vivo MMP2 short hairpin RNA delivery using recombinant adeno-associated virus and found that MMP2 deficiency significantly reduced the formation of TAD. Therefore, our study suggests that the C3a-C3aR axis contributes to the development of TAD via regulation of MMP2 expression. Targeting the C3a-C3aR axis may represent a strategy for inhibiting the formation of TAD.


Assuntos
Dissecção Aórtica/metabolismo , Complemento C3a/metabolismo , Metaloproteinase 2 da Matriz/metabolismo , Receptores de Complemento/metabolismo , Anafilatoxinas/metabolismo , Animais , Células Cultivadas , Ativação do Complemento/fisiologia , Complemento C5a/metabolismo , Modelos Animais de Doenças , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Miócitos de Músculo Liso/metabolismo , Receptor da Anafilatoxina C5a/metabolismo , Transdução de Sinais/fisiologia
20.
IEEE Trans Image Process ; 26(5): 2327-2337, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28252399

RESUMO

According to dichromatic reflection model, the previous methods of specular reflection separation in image processing often separate specular reflection from a single image using patch-based priors. Due to lack of global information, these methods often cannot completely separate the specular component of an image and are incline to degrade image textures. In this paper, we derive a global color-lines constraint from dichromatic reflection model to effectively recover specular and diffuse reflection. Our key observation is from that each image pixel lies along a color line in normalized RGB space and the different color lines representing distinct diffuse chromaticities intersect at one point, namely, the illumination chromaticity. For pixels along the same color line, they spread over the entire image and their distances to the illumination chromaticity reflect the amount of specular reflection components. With global (non-local) information from these color lines, our method can effectively separate specular and diffuse reflection components in a pixelwise way for a single image, and it is suitable for real-time applications. Our experimental results on synthetic and real images show that our method performs better than the state-of-the-art methods to separate specular reflection.

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