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1.
Nat Commun ; 15(1): 4216, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38760394

RESUMO

Antimicrobial peptides (AMPs), ancient scavengers of bacteria, are very poorly induced in macrophages infected by Mycobacterium tuberculosis (M. tuberculosis), but the underlying mechanism remains unknown. Here, we report that L-alanine interacts with PRSS1 and unfreezes the inhibitory effect of PRSS1 on the activation of NF-κB pathway to induce the expression of AMPs, but mycobacterial alanine dehydrogenase (Ald) Rv2780 hydrolyzes L-alanine and reduces the level of L-alanine in macrophages, thereby suppressing the expression of AMPs to facilitate survival of mycobacteria. Mechanistically, PRSS1 associates with TAK1 and disruptes the formation of TAK1/TAB1 complex to inhibit TAK1-mediated activation of NF-κB pathway, but interaction of L-alanine with PRSS1, disables PRSS1-mediated impairment on TAK1/TAB1 complex formation, thereby triggering the activation of NF-κB pathway to induce expression of AMPs. Moreover, deletion of antimicrobial peptide gene ß-defensin 4 (Defb4) impairs the virulence by Rv2780 during infection in mice. Both L-alanine and the Rv2780 inhibitor, GWP-042, exhibits excellent inhibitory activity against M. tuberculosis infection in vivo. Our findings identify a previously unrecognized mechanism that M. tuberculosis uses its own alanine dehydrogenase to suppress host immunity, and provide insights relevant to the development of effective immunomodulators that target M. tuberculosis.


Assuntos
Alanina , Peptídeos Antimicrobianos , Macrófagos , Mycobacterium tuberculosis , NF-kappa B , Tuberculose , Mycobacterium tuberculosis/patogenicidade , Mycobacterium tuberculosis/metabolismo , Animais , Camundongos , NF-kappa B/metabolismo , Humanos , Macrófagos/microbiologia , Macrófagos/metabolismo , Macrófagos/imunologia , Alanina/metabolismo , Peptídeos Antimicrobianos/metabolismo , Peptídeos Antimicrobianos/genética , Tuberculose/microbiologia , Tuberculose/imunologia , Alanina Desidrogenase/metabolismo , Alanina Desidrogenase/genética , MAP Quinase Quinase Quinases/metabolismo , MAP Quinase Quinase Quinases/genética , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Transdução de Sinais , Camundongos Endogâmicos C57BL , Células RAW 264.7 , Feminino
2.
Lab Chip ; 24(9): 2561-2574, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38629978

RESUMO

Tumor spheroids are now intensively investigated toward preclinical and clinical applications, necessitating the establishment of accessible and cost-effective methods for routine operations. Without losing the advantage of organ-chip technologies, we developed a rocking system for facile formation and culture of tumor spheroids in hydrogel microwells of a suspended membrane under microfluidic conditions. While the rocking is controlled with a step motor, the microfluidic device is made of two plastic plates, allowing plugging directly syringe tubes with Luer connectors. Upon injection of the culture medium into the tubes and subsequent rocking of the chip, the medium flows back and forth in the channel underneath the membrane, ensuring a diffusion-based culture. Our results showed that such a rocking- and diffusion-based culture method significantly improved the quality of the tumor spheroids when compared to the static culture, particularly in terms of growth rate, roundness, junction formation and compactness of the spheroids. Notably, dynamically cultured tumor spheroids showed increased drug resistance, suggesting alternative assay conditions. Overall, the present method is pumpless, connectionless, and user-friendly, thereby facilitating the advancement of tumor-spheroid-based applications.


Assuntos
Dispositivos Lab-On-A-Chip , Esferoides Celulares , Esferoides Celulares/citologia , Esferoides Celulares/patologia , Humanos , Técnicas de Cultura de Células/instrumentação , Difusão , Técnicas Analíticas Microfluídicas/instrumentação , Hidrogéis/química , Linhagem Celular Tumoral , Células Tumorais Cultivadas , Desenho de Equipamento
3.
RSC Adv ; 14(20): 13694-13702, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38681839

RESUMO

Currently, the photostability of photosensitizer curcumin is the main bottleneck limiting their application, reducing the bioavailability of curcumin. Studying the effect of different light sources on the photostabilities of curcumin and loading it onto polydopamine nanocarriers with better biocompatibility will help improve its light utilization efficiency. In this study, we investigated the photostabilities of curcumin and a polydopamine-based nanoparticle (polydopamine-curcumin composite nanoparticles, PDA-Cur NPs) loaded with curcumin through in vitro and in vivo experiments to achieve better antitumor effects. The results demonstrated that curcumin has good photostability in dark, but with significant photodegradation rates in both red and blue light. Blue light has a faster effect on the photodegradation of curcumin, with a degradation rate of 42.1% after 10 minutes, which is about 1.7 times that of the red light. Our study successfully synthesized PDA-Cur NPs, demonstrating its ability to stably load and release curcumin, with a loading percentage of 65.7% after 2 hours and 41.9% release in 8 hours (pH 6.0). Compared with single curcumin treatments, the photodegradation rates of PDA-Cur NPs in red and blue light treatments were reduced by 46% and 50%, respectively. Meanwhile, PDA-Cur NPs exhibited remarkable antitumor efficacy due to PDT and promote apoptosis in cancer cells, which both better than that of single curcumin treatments. Moreover, in MCF-7 tumor-bearing mice, the PDA-Cur NPs led to significant tumor growth inhibition effects, without causing evident systemic damage in vivo. The findings highlight the potential of PDA-Cur NPs as anticancer photosensitizer with greatly increased utilization of curcumin in PDT.

4.
Int Immunopharmacol ; 127: 111286, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38064818

RESUMO

PURPOSE: Since TNM staging has limitations for predicting post-operative outcomes and relapse, more effective prediction tools need to be researched and developed. Lymphovascular invasion, LVI, as a histopathological feature, has been widely shown to have a correlation with poor prognosis and early recurrence of lung adenocarcinoma (LUAD). However, LVI assessment is limited by subjective bias, and therefore its efficacy in practical clinical application needs further clarification. The aim of this study was to formulate a new signature based on LVI-related genes to predict prognosis and recurrence in patients with lung adenocarcinoma. METHODS: Clinicopathological information, gene sequencing data and whole slide images (WSIs) of LUAD patients were downloaded from the Cancer Genome Atlas (TCGA) databases. LVI statue were evaluated by professional pathologists, and then the differentially expressed genes (LVI DEGs) associated with LVI were screened. The least absolute shrinkage and selection operator (LASSO) and Step Cox regression models were used to construct LVI-associated risk scores (LVRS), including PAQR4, ARGHEF6, CKS1B, CFTR and SEC14L4. The validity of the LVRS score was evaluated on multiple external datasets and our JSSZL cohort dataset. Using LVRS scores and clinical information, nomogram were constructed for use by clinicians. In addition, we further explored the relationship between LVRS score and clinicopathological features, immune infiltration, tumor mutational load, and immunotherapy response, and confirmed the expression of key genes in LVRS score in lung adenocarcinoma tissues using qRT-PCR and immunohistochemistry (IHC) techniques. RESULTS: Based on the LVRS, patients could be classified into high-LVRS and low-LVRS groups. It was found that OS and PFS were significantly worse in the high-LVRS group than in the low-LVRS group (p < 0.001). By ROC curve analysis, it could be found that the nomogram combining LVRS and clinical information could accurately predict the prognosis of LUAD patients with the area under the curve of 1,3,5-year survival rate could reach 0.754, 0.741 and 0.735. The results of univariate and multivariate analysis showed that LVRS was an independent prognostic factor. At the same time, there were significant differences in the mutation profiles and immune microenvironment between the high-LVRS and low-LVRS groups, with the high-LVRS group having a significantly higher mutation rate than the low-LVRS group and exhibiting immunological "cold" features. By the experimental results, higher expression levels of PAQR4 and CKS1B were found in LUAD tissues, while lower expression levels of ARGHEF6, CFTR and SEC14L4 were observed. CONCLUSIONS: The LVRS established in this study serves as a valid tool to predict the prognosis and recurrence status of lung adenocarcinoma patients and has a predictive effect on the response to postoperative treatment. The establishment of LVRS may offer some theoretical support to clinical treatment strategies for patients with lung adenocarcinoma following surgical intervention.


Assuntos
Adenocarcinoma de Pulmão , Adenocarcinoma , Neoplasias Pulmonares , Humanos , Microambiente Tumoral/genética , Regulador de Condutância Transmembrana em Fibrose Cística , Recidiva Local de Neoplasia , Perfilação da Expressão Gênica , Transcriptoma , Adenocarcinoma de Pulmão/genética , Adenocarcinoma/genética , Neoplasias Pulmonares/genética , Prognóstico
5.
Cell Host Microbe ; 31(11): 1820-1836.e10, 2023 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-37848028

RESUMO

Mycobacterium tuberculosis (Mtb) triggers distinct changes in macrophages, resulting in the formation of lipid droplets that serve as a nutrient source. We discover that Mtb promotes lipid droplets by inhibiting DNA repair responses, resulting in the activation of the type-I IFN pathway and scavenger receptor-A1 (SR-A1)-mediated lipid droplet formation. Bacterial urease C (UreC, Rv1850) inhibits host DNA repair by interacting with RuvB-like protein 2 (RUVBL2) and impeding the formation of the RUVBL1-RUVBL2-RAD51 DNA repair complex. The suppression of this repair pathway increases the abundance of micronuclei that trigger the cyclic GMP-AMP synthase (cGAS)/stimulator of interferon genes (STING) pathway and subsequent interferon-ß (IFN-ß) production. UreC-mediated activation of the IFN-ß pathway upregulates the expression of SR-A1 to form lipid droplets that facilitate Mtb replication. UreC inhibition via a urease inhibitor impaired Mtb growth within macrophages and in vivo. Thus, our findings identify mechanisms by which Mtb triggers a cascade of cellular events that establish a nutrient-rich replicative niche.


Assuntos
Interferon Tipo I , Mycobacterium tuberculosis , Mycobacterium tuberculosis/genética , Urease/metabolismo , Interferon beta/metabolismo , Interferon Tipo I/metabolismo , Macrófagos/metabolismo , Nucleotidiltransferases/genética
6.
Int Immunopharmacol ; 124(Pt B): 111058, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37844466

RESUMO

Mycobacterium tuberculosis (M.tb), the most successful pathogen responsible for approximately 1.6 million deaths in 2021, employs various strategies to evade host antibacterial defenses, including mechanisms to counteract nitric oxide (NO) and certain cytokines. While Amyloid ß (A4) precursor-like protein 2 (Aplp2) has been implicated in various physiological and pathological processes, its role in tuberculosis (TB) pathogenesis remains largely uncharted. This study unveils a significant reduction in Aplp2 levels in TB patients, M.tb-infected macrophages, and mice. Intriguingly, Aplp2 mutation or knockdown results in diminished macrophage-mediated killing of M.tb, accompanied by decreased inducible nitric oxide synthase (iNOS) expression and reduced cytokine production, notably interleukin-1ß (Il-1ß). Notably, Aplp2 mutant mice exhibit heightened susceptibility to mycobacterial infection, evident through aggravated histopathological damage and increased lung bacterial loads, in contrast to Mycobacterium bovis BCG-infected wild-type (WT) mice. Mechanistically, the cleaved product of APLP2, AICD2, generated by γ-secretase, translocates to the nucleus, where it interacts with p65, culminating in enhanced the nuclear factor κB (NF-κB) transcriptional activity. This interaction triggers the upregulation of Il-1ß and iNOS expression. Collectively, our findings illuminate Aplp2's pivotal role in safeguarding against mycobacterial infections by promoting M.tb clearance through NO- or IL-1ß-mediated bactericidal effects. Therefore, we unveil a novel immune evasion strategy employed by M.tb, which could potentially serve as a target for innovative TB interventions.


Assuntos
Mycobacterium tuberculosis , Tuberculose , Humanos , Animais , Camundongos , Peptídeos beta-Amiloides/metabolismo , Macrófagos , NF-kappa B/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo
7.
Pathogens ; 12(5)2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37242324

RESUMO

Caused by the intracellular pathogen Mycobacterium tuberculosis (Mtb), tuberculosis (TB) remains a massive global public health issue. A well-known and key TB trait is caseous necrotic granuloma, which allows mycobacteria to reactivate and disseminate, thus confounding TB eradication programs. Amino acid (AA) metabolism is key to regulating immune responses in Mtb infections; however, it is currently unclear if AAs can be used to treat tuberculous granulomas. Here, we screened 20 proteinogenic AAs using a Mycobacterium marinum-infected zebrafish granuloma model. Only L-tyrosine simultaneously reduced Mycobacterium marinum (M. marinum) levels in zebrafish larvae and adults and inhibited intracellular pathogen survival levels. Mechanistically, L-tyrosine significantly upregulated interferon-γ (IFN-γ) expression in M. marinum -infected zebrafish adults but not in larvae. Using N-acetylcysteine (NAC) to inhibit reactive oxygen species (ROS), L-tyrosine appeared to inhibit Mtb intracellular survival by promoting ROS production. Thus, L-tyrosine as a non-essential AA may reduce mycobacterial survival in both macrophages and tuberculous granulomas. Our research provides a platform for the clinical development of AAs for active or latent TB patients infected with drug-sensitive or drug-resistant Mtb.

8.
Cancer Sci ; 114(5): 1830-1845, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36718950

RESUMO

Immune microenvironment could affect the biological progress in prostate cancer (PCa) through N6 methyl adenosine (m6A) methylation. The purpose of this study was to investigate the crosstalk between m6A methylation and immune microenvironment and explore potential biomarkers to improve the immunotherapeutic response. Firstly, according to 11 differentially expressed m6A genes between normal and tumor samples, PCa patients were divided into immune microenvironment subtype 1 (IMS1) and IMS2 based on m6A gene profiles extracted from The Cancer Genome Atlas (TCGA) database. IMS2 showed an immune "cold" phenotype with worse prognoses, and HNRNPC was identified as the biomarker of IMS2 by the protein-protein interaction network. Furthermore, through bioinformatics analyses and in vitro experiments, we found that HNRNPC-high patients showed a suppressive immune-infiltrating tumor microenvironment with a higher infiltration of regulatory T (Treg) cells. Finally, we cocultured transfected PCa cells with peripheral blood mononuclear cells (PBMC) and verified that HNRNPC inhibits tumor immunity by elevating the activation of Treg cells and suppression of effector CD8 T cell. In conclusion, we identified a "cold" immune phenotype in PCa, and HNRNPC regulating the activation of Treg cells. Activation of the immune microenvironment through targeting HNRNPC may be a potential therapeutic option for advanced PCa.


Assuntos
Neoplasias da Próstata , Linfócitos T Reguladores , Masculino , Humanos , Leucócitos Mononucleares , Microambiente Tumoral/genética , Neoplasias da Próstata/genética , Adenosina , Ribonucleoproteínas Nucleares Heterogêneas Grupo C
9.
Front Mol Biosci ; 9: 887887, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36090038

RESUMO

Intraductal papillary mucinous neoplasm (IPMN) is a common pancreatic precancerous lesion, with increasing incidence in recent years. However, the mechanisms of IPMN progression into invasive cancer remain unclear. The mRNA expression data of IPMN/PAAD patients were extracted from the TCGA and GEO databases. First, based on GSE19650, we analyzed the molecular alterations, tumor stemness, immune landscape, and transcriptional regulation of IPMN progression. The results indicated that gene expression changed dramatically, specifically at the intraductal papillary-mucinous adenoma (IPMA) stage. Gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and Kyoto Encyclopedia of Genes and Genomes (GSEA) pathway analyses showed that glycoprotein-related, cell cycle, and P53 pathways displayed the most significant changes during progression. With IPMN progression, tumor stemness increased continuously, and KRAS, ERBB3, RUNX1, and ELF3 are essential driver genes affecting tumor stemness. Motif analysis suggested that KLF4 may be a specific transcription factor that regulates gene expression in the IPMA stage, while MYB and MYBL1 control gene expression in the IPMC and invasive stages, respectively. Then, GSE19650 and GSE71729 transcriptome data were combined to perform the least absolute shrinkage and selection operator (LASSO) method and Cox regression analysis to develop an 11-gene prediction model (KCNK1, FHL2, LAMC2, CDCA7, GPX3, C7, VIP, HBA1, BTG2, MT1E, and LYVE1) to predict the prognosis of pancreatic cancer patients. The reliability of the model was validated in the GSE71729 and TCGA databases. Finally, 11 additional IPMN patients treated in our hospital were included, and the immune microenvironment changes during IPMN progression were analyzed by immunohistochemistry (IHC). IHC results suggest that Myeloid-derived suppressor cells (MDSCs) and macrophages may be key in the formation of immunosuppressive microenvironment of IPMN progression. Our study deepens our understanding of IPMN progression, especially the changes in the immune microenvironment. The findings of this work may contribute to the development of new therapeutic strategies for IPMN.

10.
Front Med (Lausanne) ; 9: 832052, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35445039

RESUMO

Background: Silicosis poses a threat to workers' health due to the irreversible lung lesions. Design: A retrospective cohort study. Methods: A total of 259 patients [80 worked with artificial stone (AS), 179 with non-artificial stone (non-AS)] with confirmed silicosis were included in this study. Forty-one of AS and 91 of non-AS had approximately 2 years' follow-up records [lung function tests and high-resolution computer tomography (HRCT)]. Compared with the first records, increased, densified, or newly emerging lesions in lung HRCT images were judged as progression of the disease. Cox proportional hazards models were used to determine the risk factors. Kaplan-Meier survival curve and log-rank test were used to compare prognostic factors for cumulative risk of progression. Results: In 132 patients with median follow-up of 24.0 months (IQR, 13.8, 24.9), 66 patients showed progression, in them, 36 (87.8%) were from AS group and 30 (32.9%) from non-AS group. Working experience of AS processing (hazard ratio, 5.671; 95% CI, 3.048-10.550) and complicated silicosis in CT images (hazard ratio, 2.373; 95% CI, 1.379-4.082) were the main risk factors associated with progression. Forced vital capacity decreased after 1-year (241.5 vs. 55.2 mL) and 2-year (328.1 vs. 68.8 mL) follow-up in the two groups (AS vs. non-AS). History of anti-tuberculosis medication, chest oppression and pain, ground-glass opacity, pleural abnormalities, and restrictive pulmonary dysfunction were more frequently found on HRCT images in the AS group than non-AS group. Lung functions (DLCO, %) were lower in the current/former smokers than the non-smokers (P < 0.05) in AS patients. Conclusion: Prevention and protection rules are needed to be enforced in the occupation involving AS processing; smoking may be associated with declined lung function in AS patients.

11.
Cell Discov ; 7(1): 90, 2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34608123

RESUMO

Pathogenic mycobacteria induce the formation of hypoxic granulomas during latent tuberculosis (TB) infection, in which the immune system contains, but fails to eliminate the mycobacteria. Fatty acid metabolism-related genes are relatively overrepresented in the mycobacterial genome and mycobacteria favor host-derived fatty acids as nutrient sources. However, whether and how mycobacteria modulate host fatty acid metabolism to drive granuloma progression remains unknown. Here, we report that mycobacteria under hypoxia markedly secrete the protein Rv0859/MMAR_4677 (Fatty-acid degradation A, FadA), which is also enriched in tuberculous granulomas. FadA acts as an acetyltransferase that converts host acetyl-CoA to acetoacetyl-CoA. The reduced acetyl-CoA level suppresses H3K9Ac-mediated expression of the host proinflammatory cytokine Il6, thus promoting granuloma progression. Moreover, supplementation of acetate increases the level of acetyl-CoA and inhibits the formation of granulomas. Our findings suggest an unexpected mechanism of a hypoxia-induced mycobacterial protein suppressing host immunity via modulation of host fatty acid metabolism and raise the possibility of a novel therapeutic strategy for TB infection.

12.
Mitochondrial DNA B Resour ; 6(9): 2575-2577, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34377833

RESUMO

The genus Cuneopsis Simpson, 1900 comprises seven valid species, and Cuneopsis celtiformis (Heude, 1874) is the type species of this genus. Previous phylogenetic studies using complete mitochondrial genomes showed that Cuneopsis was not monophyletic, but the result was hampered by incomplete species sampling and lack of the type species of this genus. In this study, we collected C. celtiformis from the type locality and determined its complete maternal mitochondrial genome. This mitogenome is 15,922 bp in length and contains 14 protein-coding genes (including one F-orf), two rRNA genes, 22 tRNA genes, and 1 putative control region. Our mitochondrial phylogenomic analysis confirms that currently recognized genus Cuneopsis is polyphyletic, and C. celtiformis is the closest to C. heudei with high maximum likelihood bootstrap support value. Comprehensive sampling of all Cuneopsis species is needed for phylogenetic analysis to erect new genera in future studies.

13.
Environ Sci Pollut Res Int ; 28(42): 59784-59791, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34145544

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) are environmental chemicals that are formed due to incomplete combustion of the organic matters, or during heat treatment of the food. The objectives of the present study were first to estimate levels of the 15-priority PAHs in the edible vegetable oil (corn oil, sunflower oil, olive oil, and canola oil) collected from Egypt. Furthermore, the effect of heat treatment on the formation of PAHs in the canola oil was further examined. In addition, dietary intakes and cancer risk among Egyptian consumers were additionally calculated. The achieved results indicated presence of 15-priority PAHs in all examined oil samples. Canola oil had the highest residual concentrations of PAHs compared with the other tested oil species. Heat treatment of canola oil led to a drastic increase in the formed B[a]P (316.55%), total 2-PAHs (322.47%), total 4-PAHs (297.42%), total 8-PAHs (285.26%), and total 15-PAHs (443.32%), respectively. The incremental lifetime cancer risk among the Egyptian population is considered safe when was calculated for all examined oil samples.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Monitoramento Ambiental , Óleos de Plantas , Hidrocarbonetos Policíclicos Aromáticos/análise , Óleo de Brassica napus , Medição de Risco , Verduras
14.
Appl Bionics Biomech ; 2021: 8898311, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33574891

RESUMO

In interventional surgery, the manual operation of the catheter is not accurate. It is necessary to operate the catheter skillfully and effectively to protect the surgeon from radiation injury. The purpose of this paper is to design a new robot catheter operating system, which can help surgeons to complete the operation with high mechanical precision. On the basis of the original mechanical structure-real catheter, the operation information of the main end operator is collected. After the information is collected, the control algorithm of the system is improved, and the BP neural network is combined with the traditional PID controller to adjust the PID control parameters more effectively and intelligently so that the motor can reflect the output of the controller better and faster. The feasibility and superiority of the BP neural network PID controller are verified by simulation experiments.

15.
J Biomed Res ; 36(1): 10-21, 2021 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-35403606

RESUMO

c-Met is a hepatocyte growth factor receptor overexpressed in many tumors such as hepatocellular carcinoma (HCC). Therefore, c-Met may serve as a promising target for HCC immunotherapy. Modifying T cells to express c-Met-specific chimeric antigen receptor (CAR) is an attractive strategy in treating c-Met-positive HCC. This study aimed to systematically evaluate the inhibitory effects of 2 nd- and 3 rd-generation c-Met CAR-T cells on hepatocellular carcinoma (HCC) cells. Here, 2 nd- and 3 rd-generation c-Met CARs containing an anti-c-Met single-chain variable fragment (scFv) as well as the CD28 signaling domain and CD3ζ (c-Met-28-3ζ), the CD137 signaling domain and CD3ζ (c-Met-137-3ζ), or the CD28 and CD137 signaling domains and CD3ζ (c-Met-28-137-3ζ) were constructed, and their abilities to target c-Met-positive HCC cells were evaluated in vitro and in vivo. All c-Met CARs were stably expressed on T cell membrane, and c-Met CAR-T cells aggregated around c-Met-positive HCC cells and specifically killed them in vitro. c-Met-28-137-3ζ CAR-T cells secreted more interferon-gamma (IFN-γ) and interleukin 2 (IL-2) than c-Met-28-3ζ CAR-T cells and c-Met-137-3ζ CAR-T cells. Compared with c-Met low-expressed cells, c-Met CAR-T cells secreted more cytokines when co-cultured with c-Met high-expressed cells. Moreover, c-Met-28-137-3ζ CAR-T cells eradicated HCC more effectively in xenograft tumor models compared with the control groups. This study suggests that 3 rd-generation c-Met CAR-T cells are more effective in inhibiting c-Met-positive HCC cells than 2 nd-generation c-Met CAR-T cells, thereby providing a promising therapeutic intervention for c-Met-positive HCC.

16.
Nature ; 577(7792): 682-688, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31942069

RESUMO

Mycobacterium tuberculosis is an intracellular pathogen that uses several strategies to interfere with the signalling functions of host immune molecules. Many other bacterial pathogens exploit the host ubiquitination system to promote pathogenesis1,2, but whether this same system modulates the ubiquitination of M. tuberculosis proteins is unknown. Here we report that the host E3 ubiquitin ligase ANAPC2-a core subunit of the anaphase-promoting complex/cyclosome-interacts with the mycobacterial protein Rv0222 and promotes the attachment of lysine-11-linked ubiquitin chains to lysine 76 of Rv0222 in order to suppress the expression of proinflammatory cytokines. Inhibition of ANAPC2 by specific short hairpin RNA abolishes the inhibitory effect of Rv0222 on proinflammatory responses. Moreover, mutation of the ubiquitination site on Rv0222 impairs the inhibition of proinflammatory cytokines by Rv0222 and reduces virulence during infection in mice. Mechanistically, lysine-11-linked ubiquitination of Rv0222 by ANAPC2 facilitates the recruitment of the protein tyrosine phosphatase SHP1 to the adaptor protein TRAF6, preventing the lysine-63-linked ubiquitination and activation of TRAF6. Our findings identify a previously unrecognized mechanism that M. tuberculosis uses to suppress host immunity, and provide insights relevant to the development of effective immunomodulators that target M. tuberculosis.


Assuntos
Proteínas de Bactérias/imunologia , Proteínas de Bactérias/metabolismo , Interações Hospedeiro-Patógeno/imunologia , Mycobacterium tuberculosis/imunologia , Tuberculose/imunologia , Ubiquitinação , Ciclossomo-Complexo Promotor de Anáfase/química , Animais , Subunidade Apc2 do Ciclossomo-Complexo Promotor de Anáfase/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Células Cultivadas , Citocinas/antagonistas & inibidores , Citocinas/imunologia , Citocinas/metabolismo , Feminino , Mediadores da Inflamação/antagonistas & inibidores , Mediadores da Inflamação/imunologia , Mediadores da Inflamação/metabolismo , Lisina/metabolismo , Macrófagos/imunologia , Macrófagos/metabolismo , Macrófagos/microbiologia , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 6/metabolismo , Transdução de Sinais , Fator 6 Associado a Receptor de TNF/antagonistas & inibidores , Fator 6 Associado a Receptor de TNF/metabolismo , Fator de Transcrição AP-1/metabolismo , Tuberculose/microbiologia , Virulência/imunologia
17.
Med Sci Monit ; 26: e919566, 2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31964857

RESUMO

BACKGROUND Chemotherapy is widely used in gastric cancer treatment, but multidrug resistance remains a leading cause of chemotherapy failure. Trop2 is highly expressed in gastric tumor tissues and greatly influences cancer progression. However, little is known about the relationship between Trop2 and drug resistance in gastric cancer. MATERIAL AND METHODS In the present study, Trop2 was knocked down in BGC823 cells and overexpressed in HGC27. CCK-8 assay was performed to explore the relationship of Trop2 expression and cell proliferation treated with anticancer drugs. Flow cytometry was performed to assess the relationship between Trop2 and cell apoptosis after chemotherapy. Subcutaneous xenograft models were generated to explore the curative effect of DDP to GC in vivo. MRP1 and Notch1 expressions were assessed by Western blot. RESULTS Trop2 decreased cell proliferation inhibition and apoptosis after chemotherapeutic treatments. DDP showed stronger therapeutic effects on Trop2-knockdown tumor than control in vivo. MRP1 and Notch1 signaling pathway were confirmed to participate in Trop2-induced drug resistance. CONCLUSIONS Our findings suggest that Trop2 promotes the resistance of gastric cancer to chemotherapy by activating the Notch1 pathway.


Assuntos
Antígenos de Neoplasias/genética , Moléculas de Adesão Celular/genética , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/metabolismo , Antígenos de Neoplasias/metabolismo , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Moléculas de Adesão Celular/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cisplatino/farmacologia , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos , Humanos , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , RNA Longo não Codificante/metabolismo , RNA Interferente Pequeno/farmacologia , Receptor Notch1/deficiência , Receptor Notch1/metabolismo , Transdução de Sinais/efeitos dos fármacos , Neoplasias Gástricas/patologia
18.
Ann Bot ; 125(1): 29-47, 2020 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-31314080

RESUMO

BACKGROUND AND AIMS: Whole-genome duplication (WGD) events are considered important driving forces of diversification. At least 11 out of 52 Brassicaceae tribes had independent mesopolyploid WGDs followed by diploidization processes. However, the association between mesopolyploidy and subsequent diversification is equivocal. Herein we show the results from a family-wide diversification analysis on Brassicaceae, and elaborate on the hypothesis that polyploidization per se is a fundamental driver in Brassicaceae evolution. METHODS: We established a time-calibrated chronogram based on whole plastid genomes comprising representative Brassicaceae taxa and published data spanning the entire Rosidae clade. This allowed us to set multiple calibration points and anchored various Brassicaceae taxa for subsequent downstream analyses. All major splits among Brassicaceae lineages were used in BEAST analyses of 48 individually analysed tribes comprising 2101 taxa in total using the internal transcribed spacers of nuclear ribosomal DNA. Diversification patterns were investigated on these tribe-wide chronograms using BAMM and were compared with family-wide data on genome size variation and species richness. KEY RESULTS: Brassicaceae diverged 29.9 million years ago (Mya) during the Oligocene, and the majority of tribes started diversification in the Miocene with an average crown group age of about 12.5 Mya. This matches the cooling phase right after the Mid Miocene climatic optimum. Significant rate shifts were detected in 12 out of 52 tribes during the Mio- and Pliocene, decoupled from preceding mesopolyploid WGDs. Among the various factors analysed, the combined effect of tribal crown group age and net diversification rate (speciation minus extinction) is likely to explain sufficiently species richness across Brassicaceae tribes. CONCLUSIONS: The onset of the evolutionary splits among tribes took place under cooler and drier conditions. Pleistocene glacial cycles may have contributed to the maintenance of high diversification rates. Rate shifts are not consistently associated with mesopolyploid WGD. We propose, therefore, that WGDs in general serve as a constant 'pump' for continuous and high species diversification.


Assuntos
Brassicaceae , Magnoliopsida , Evolução Molecular , Filogenia
19.
Onco Targets Ther ; 12: 9341-9350, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31807014

RESUMO

PURPOSE: In previous research, we have found that LMP1-specific chimeric antigen (HELA/CAR) T cells can specifically recognize and kill LMP1-positive NPC cells. However, the tumor-inhibitory effectiveness of HELA/CART cells needs to be enhanced. METHODS: We created two CARs that contain the T cell receptor-ζ (TCR-ζ) signal transduction domain with the CD28 and CD137 (4-1BB) or CD134 (OX-40) intracellular domains in tandem (HELA/137CAR or HELA/134CAR). Then, the tumor-inhibitory functions of two new CAR-T cells were investigated, both in vitro and in vivo. RESULTS: The results showed that, after short-term expansion, primary human T cells were subjected to lentiviral gene transfer, resulting in large numbers of cells with >80% CAR expression. All CART cells were effective in killing SUNE1-LMP1 and C1R-neo cells, while HELA/137CART cells produced greater quantities of IFN-γ and IL-2 than HELA/CART cells. However, the level of IL-2 not INF-γ secreted by HELA/134CART cells was increased under the stimulation of LMP1 antigen. In an LMP1-positive NPC mouse xenograft model, HELA/137CART cells exhibited better antitumor activity and longer survival time in vivo compared with HELA/CAR T cells. CONCLUSION: The findings suggest that CD137 and CD28 is a better costimulatory signaling domain than CD28 only for optimizing tumor-inhibitory roles.

20.
Biomed Res Int ; 2019: 7604851, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31687396

RESUMO

Pyrene is one of the major polycyclic aromatic hydrocarbons formed during heat treatment of meat and in car exhausts; however, few studies have investigated pyrene-induced adverse effects on human cell lines. This study aimed at the investigation of pyrene-induced cytotoxicity and oxidative damage in human liver HepG2 cells at environmentally relevant concentrations. Pyrene-induced changes in mRNA expression of xenobiotic metabolizing enzymes (XMEs), xenobiotic transporters, antioxidant enzymes, and inflammatory markers were investigated using real-time PCR. As a protection trial, the ameliorative effects of lycopene, a carotenoid abundantly found in tomato, were investigated. The possible mechanisms behind such effects were examined via studying the co exposure effects of pyrene and lycopene on regulatory elements including the aryl hydrocarbon receptor (Air) and elytroid 2-related factor 2 (RF). The achieved results indicated that pyrene caused significant cytotoxicity at 50 n, with a clear production of reactive oxygen species (ROS) in a dose-dependent manner. Pyrene upregulated mRNA expression of phase I enzymes including CYP1A1, 1A2, and CYP1B1 and inflammatory markers including TNFα and Cox2. However, pyrene significantly downregulated phase II enzymes, xenobiotic transporters, and antioxidant enzymes. Interestingly, lycopene significantly reduced pyrene-induced cytotoxicity and ROS production. Moreover, lycopene upregulated detoxification and antioxidant enzymes, probably via its regulatory effects on Air- and RF-dependent pathways.


Assuntos
Biomarcadores Tumorais/metabolismo , Inflamação/tratamento farmacológico , Fígado/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Pirenos/farmacologia , Transcriptoma/efeitos dos fármacos , Xenobióticos/farmacologia , Antioxidantes/farmacologia , Carotenoides/farmacologia , Citotoxinas/farmacologia , Regulação para Baixo/efeitos dos fármacos , Células Hep G2 , Humanos , Inativação Metabólica/efeitos dos fármacos , Inflamação/metabolismo , Fígado/metabolismo , Licopeno/farmacologia , Oxirredução/efeitos dos fármacos , Hidrocarbonetos Policíclicos Aromáticos/farmacologia , RNA Mensageiro/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Receptores de Hidrocarboneto Arílico/metabolismo , Regulação para Cima/efeitos dos fármacos
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