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1.
Cell Mol Life Sci ; 81(1): 424, 2024 Oct 05.
Article de Anglais | MEDLINE | ID: mdl-39367988

RÉSUMÉ

BACKGROUND: Our previous study found that tumor suppressor nitrogen permease regulator like-2(NPRL2) is frequently downregulated in glioma, leading to malignant growth. However, NPRL2-mediated crosstalk between tumor cells and immune cells remains unclear. METHODS: The regulatory effects of NPRL2 on tripartite motif-containing protein 16(TRIM16) dependent ubiquitination degradation of Galectin-3(Gal-3) were explored. The effects of Gal-3 on copper uptake, immunocompetence and cuproptosis were investigated in CD8+T lymphocytes(CD8+T cells). The ability of NPRL2 to protect CD8+T cells from Gal-3 damage was evaluated. Furthermore, the correlations among NPRL2, TRIM16, Gal-3 and CD8+T cell accumulation were analyzed in glioma clinical specimens. RESULTS: NPRL2 increased the TRIM16 expression via inactivation of ERK1/2, which in turn promoted the ubiquitination-mediated degradation of Gal-3 and diminished Gal-3 release from glioma cells. Moreover, Gal-3 accelerated copper uptake and triggered cuproptosis in CD8+T cells, whereas NPRL2 increased CD8+T cell recruitment and prevented impairment of CD8+T cells by Gal-3. Clinical samples revealed that NPRL2 expression was positively associated with TRIM16 expression and negatively correlated with Gal-3, but Gal-3 expression was negatively associated with CD8+T cell accumulation. CONCLUSION: Glioma-derived NPRL2/TRIM16/Gal-3 axis participates in the regulation of CD8+T cell cuproptosis, which provides a promising strategy to rescue the immune activity of CD8+T cells and reverse immunosuppression in glioma.


Sujet(s)
Lymphocytes T CD8+ , Galectine -3 , Gliome , Protéines à motif tripartite , Ubiquitin-protein ligases , Ubiquitination , Humains , Lymphocytes T CD8+/métabolisme , Lymphocytes T CD8+/immunologie , Gliome/métabolisme , Gliome/anatomopathologie , Gliome/immunologie , Gliome/génétique , Protéines à motif tripartite/métabolisme , Protéines à motif tripartite/génétique , Ubiquitin-protein ligases/métabolisme , Ubiquitin-protein ligases/génétique , Galectine -3/métabolisme , Galectine -3/génétique , Lignée cellulaire tumorale , Femelle , Mâle , Animaux , Tumeurs du cerveau/métabolisme , Tumeurs du cerveau/anatomopathologie , Tumeurs du cerveau/immunologie , Protéines suppresseurs de tumeurs/métabolisme , Protéines suppresseurs de tumeurs/génétique
2.
J Cancer ; 15(17): 5691-5709, 2024.
Article de Anglais | MEDLINE | ID: mdl-39308687

RÉSUMÉ

Background: Several studies have reported the relationship between α2C-adrenergic receptor (ADRA2C) and both neoplastic and non-neoplastic diseases. However, a comprehensive pan-cancer analysis is currently lacking. Methods: Utilizing the RNA sequencing (RNA-seq) datasets from The Cancer Genome Atlas (TCGA) database, the roles of ADRA2C in human pan-cancer were analyzed through a variety of bioinformatics approaches, including R programming language and single-cell sequencing data analysis, et al. Besides, cell migration assay and immunochemistry were employed to further validate the role of ADRA2C in glioblastoma multiforme (GBM) cell lines and GBM mouse model. Results: A total of 33 cancer types were involved in this study. It was revealed that the expression level of ADRA2C varied across different clinical stages in patients with breast invasive carcinoma (BRCA), esophageal adenocarcinoma (ESCA), kidney renal papillary cell carcinoma (KIRP) and lung squamous cell carcinoma (LUSC). Meanwhile, it was found that ADRA2C may play roles in prognosis of adrenocortical carcinoma (ACC), glioblastoma multiforme and lower grade glioma (GBM-LGG), and uveal melanoma (UVM). Functional enrichment analysis suggested that ADRA2C expression level was highly correlated with neuronal system-related pathways. Moreover, ADRA2C may be a promising diagnostic marker for cervical squamous cell carcinoma and endocervical adenocarcinoma (CESC), cholangiocarcinoma (CHOL), GBM, GBMLGG, kidney chromophobe (KICH), and KIRP. Additionally, ADRA2C expression level was correlated with the levels of several infiltrating cells and immune checkpoint genes. Besides, the single-cell sequencing data analysis indicated that ADRA2C played a role in multiple tumor development processes in GBM, retinoblastoma (RB), and UVM. Finally, in vitro and in vivo experiments confirmed that the expression level of ADRA2C may be associated with glioma cell migration, apoptosis, and invasion. Conclusion: ADRA2C exhibited to play a notable role in several cancer types, suggesting that ADRA2C could serve as a promising biomarker or target for cancer diagnosis, prognosis, and treatment, particularly for GBM.

3.
Glob Health Res Policy ; 9(1): 39, 2024 Sep 26.
Article de Anglais | MEDLINE | ID: mdl-39327625

RÉSUMÉ

BACKGROUND: Infectious diseases persistently pose global threats, and it is imperative to accelerate the professionalization of public health workforce. This study aimed to develop and validate the infectious disease control competency scale (IDCCS) for public health professionals to fill a theoretical gap and elevate practical capabilities by informing public health professionals' development goals. METHODS: The initial item pool was generated through a literature review, and categorized into three dimensions (knowledge, practical skills, and leadership) based on the competency iceberg model and public health leadership framework. A two-round Delphi process was conducted to determine indicators within the scale. A pilot survey was utilized for item analysis and exploratory factor analysis (EFA). A formal survey was employed for confirmatory factor analysis (CFA). The weight value of each indicator was calculated using the analytic hierarchy process. RESULTS: An initial scale with three primary items, 14 secondary items, and 81 tertiary items was generated. Twenty experts participated in the two rounds of the Delphi process. Authority coefficients exceeded 0.9 in both rounds. Kendall's W was 0.29 and 0.19, respectively (both P < 0.001). Item analysis presented a Cronbach's Alpha of 0.98, with corrected item-total correlation coefficients ranging from 0.33 to 0.78. EFA demonstrated that cumulative variance explanations for the four primary dimensions (knowledge, practical skills, leadership, and personal quality) were 77.463%, 73.976%, 81.174%, and 68.654%, respectively. CFA indicated that all composite reliability values and average variance extracted surpassed 0.8 and 0.5, respectively. The standardized factor loadings of the items ranged from 0.630 to 0.977. Among the seven model fit indices, each of the four dimensions satisfied at least five criteria. A final three-level scale comprising four primary items, 14 secondary items, and 64 tertiary items was constructed. The weight values for the four primary items were 0.4064, 0.2878, 0.2082, and 0.0981, respectively. CONCLUSIONS: The IDCCS was established to evaluate the competencies of knowledge, practical skills, leadership, and personal quality for public health professionals in infectious disease control. This scale demonstrates good reliability and validity, and can be used for performance evaluation, recruitment processes, curriculum development, and individual self-assessment.


Sujet(s)
Méthode Delphi , Humains , Compétence professionnelle/statistiques et données numériques , Contrôle des maladies transmissibles/méthodes , Contrôle des maladies transmissibles/statistiques et données numériques , Leadership , Santé publique/statistiques et données numériques , Enquêtes et questionnaires , Personnel de santé/statistiques et données numériques , Personnel de santé/psychologie , Reproductibilité des résultats , Adulte , Femelle , Mâle
5.
Eur Rev Aging Phys Act ; 21(1): 22, 2024 Aug 30.
Article de Anglais | MEDLINE | ID: mdl-39215230

RÉSUMÉ

Physical exercise is recognized for its beneficial effects on brain health and executive function, particularly through the careful manipulation of key exercise parameters, including type, intensity, and duration. The aim of this systematic review and meta-analysis was to delineate the optimal types, intensities, and durations of exercise that improve cognitive functions in older adults with mild cognitive impairment (MCI) or dementia. A comprehensive search was conducted in Scopus, Web of Science, and PubMed from their inception until December 2023. The methodological quality and publication bias of the included studies were assessed using the PEDro scale and Egger's regression test, respectively. Separate meta-analyses were performed to assess the overall impact of exercise on cognitive assessments and to explore the effects of different exercise types (i.e., aerobic, resistance, dual-task, mind-body, and multi-component exercises) and intensities (i.e., low, moderate, and high) on executive function. Results were presented as standardized mean differences (SMD) and 95% confidence intervals (95% CI). A meta-regression analysis was conducted to examine the correlation between exercise duration and mean effects. In total, 15,087 articles were retrieved from three databases, of which 35 studies were included in our final analyses. The results indicated high overall methodological quality (PEDro score = 8) but a potential for publication bias (t = 2.08, p = 0.045). Meta-analyses revealed that all types of exercise (SMD = 0.691, CI [0.498 to 0.885], p < 0.001) and intensities (SMD = 0.694, CI [0.485 to 0.903], p < 0.001) show significant effects favoring exercise. Notably, dual-task exercises (SMD = 1.136, CI [0.236 to 2.035], p < 0.001) and moderate-intensity exercises (SMD = 0.876, CI [0.533 to 1.219], p < 0.001) exhibited the greatest effect. No significant correlation was observed between exercise duration and SMD (R² = 0.038, p = 0.313). Overall, our meta-analyses support the role of physical exercise in enhancing executive function in older adults with MCI or dementia. It is essential to carefully tailor exercise parameters, particularly type and intensity, to meet the specific needs of older adults with MCI or dementia. Such customization is crucial for optimizing executive function outcomes and improving overall brain health.

6.
Cancer Commun (Lond) ; 2024 Aug 01.
Article de Anglais | MEDLINE | ID: mdl-39087354

RÉSUMÉ

The intratumoral microbiome (TM) refers to the microorganisms in the tumor tissues, including bacteria, fungi, viruses, and so on, and is distinct from the gut microbiome and circulating microbiota. TM is strongly associated with tumorigenesis, progression, metastasis, and response to therapy. This paper highlights the current status of TM. Tract sources, adjacent normal tissue, circulatory system, and concomitant tumor co-metastasis are the main origin of TM. The advanced techniques in TM analysis are comprehensively summarized. Besides, TM is involved in tumor progression through several mechanisms, including DNA damage, activation of oncogenic signaling pathways (phosphoinositide 3-kinase [PI3K], signal transducer and activator of transcription [STAT], WNT/ß-catenin, and extracellular regulated protein kinases [ERK]), influence of cytokines and induce inflammatory responses, and interaction with the tumor microenvironment (anti-tumor immunity, pro-tumor immunity, and microbial-derived metabolites). Moreover, promising directions of TM in tumor therapy include immunotherapy, chemotherapy, radiotherapy, the application of probiotics/prebiotics/synbiotics, fecal microbiome transplantation, engineered microbiota, phage therapy, and oncolytic virus therapy. The inherent challenges of clinical application are also summarized. This review provides a comprehensive landscape for analyzing TM, especially the TM-related mechanisms and TM-based treatment in cancer.

7.
Plant Physiol Biochem ; 215: 109018, 2024 Oct.
Article de Anglais | MEDLINE | ID: mdl-39137678

RÉSUMÉ

Polyphenol oxidase (PPO) activity drives walnut fruit browning, but the roles of its only two-family genes, JrPPO1 and JrPPO2, remain unclear. This study explores the spatiotemporal expression and enzymatic characteristics of JrPPO1 and JrPPO2 in walnut. Treatment with the PPO activator CuSO4 and H2O2 accelerated fruit browning and up-regulated JrPPO1/2 expression, whereas treatment with the PPO inhibitor ascorbic acid delayed browning, down-regulating JrPPO1 and up-regulating JrPPO2 expression. Compared to mJrPPO1, mJrPPO2 can exhibited better enzyme activity at higher temperatures (47 °C) and in more acidic environments (pH 4.25). mJrPPO2 exhibited a higher substrate specificity over mJrPPO1, and the preferred substrates are catechol, chlorogenic acid, and epicatechin. Additionally, mJrPPO2 adapted better to low concentration of oxygen (as low as 1.0% O2) and slightly elevated CO2 levels compared to mJrPPO1. Subcellular localization and spatiotemporal expression patterns showed that JrPPO1 is only expressed in green tissues and located in chloroplasts, while JrPPO2 is also located in chloroplasts, partly associated with membranes, and is expressed in both green and non-green tissues. Silencing JrPPO1/2 with virus-induced gene silencing (VIGS) reduced fruit browning, maintained higher total phenols, and decreased MDA production. Notably, silencing JrPPO1 had a greater impact on browning than JrPPO2, indicating JrPPO1's greater contribution to PPO activity and fruit browning in walnut fruits. Consequently, JrPPO1 can be effectively regulated both at the molecular level and by manipulating environmental conditions, to achieve the objective of controlling fruit browning.


Sujet(s)
Catechol oxidase , Fruit , Régulation de l'expression des gènes végétaux , Juglans , Protéines végétales , Protéines végétales/métabolisme , Protéines végétales/génétique , Fruit/génétique , Fruit/métabolisme , Juglans/génétique , Juglans/métabolisme , Catechol oxidase/métabolisme
8.
Materials (Basel) ; 17(15)2024 Aug 03.
Article de Anglais | MEDLINE | ID: mdl-39124516

RÉSUMÉ

Crack generation and propagation are critical aspects of grinding processes for hard and brittle materials. Despite extensive research, the impact of residual cracks from coarse grinding on the cracks generated during fine grinding remains unexplored. This study aims to bridge this gap by examining the propagation law of existing cracks under indentation using the extended finite element method. The results reveal that prefabricated cracks with depths less than the crack depth produced on an undamaged surface tend to extend further without surpassing the latter. Conversely, deeper prefabricated cracks do not exhibit significant expansion. A novel method combining indentation and prefabricated cracks with fracture strength tests is proposed to determine crack propagation. Silicon wafers with varying damaged surfaces are analyzed, and changes in fracture strength, measured by the ball-on-ring method, are utilized to determine crack propagation. The experimental results confirm the proposed crack evolution law, validated by damage assessments across different grinding processes, which is suitable for crack damage. The findings demonstrate that residual cracks from coarse grinding are negligible in predicting the maximum crack depth during fine grinding. This research provides a crucial foundation for optimizing the wafer thinning process in 3D stacked chip manufacturing, establishing that changes in fracture strength are a reliable indicator of crack propagation feasibility.

9.
Angew Chem Int Ed Engl ; : e202412553, 2024 Aug 12.
Article de Anglais | MEDLINE | ID: mdl-39133133

RÉSUMÉ

Efficient photocatalytic CO2 reduction coupled with the photosynthesis of pure H2O2 is a challenging and significant task. Herein, using classical CO2 photoreduction site iron porphyrinate as the linker, Ag(I) clusters were spatially separated and evenly distributed within a new metal-organic framework (MOF), namely Ag27TPyP-Fe. With water as electron donors, Ag27TPyP-Fe exhibited remarkable performances in artificial photosynthetic overall reaction with CO yield of 36.5 µmol g-1 h-1 and ca. 100% selectivity, as well as H2O2 evolution rate of 35.9 µmol g-1 h-1. Since H2O2 in the liquid phase can be more readily separated from the gaseous products of CO2 photoreduction, high-purity H2O2 with a concentration up to 0.1 mM was obtained. Confirmed by theoretical calculations and the established energy level diagram, the reductive iron(II) porphyrinates and oxidative Ag(I) clusters within an integrated framework functioned synergistically to achieve artificial photosynthesis. Furthermore, photoluminescence spectroscopy and photoelectrochemical measurements revealed that the robust connection of Ag(I) clusters and iron porphyrinate ligands facilitated efficient charge separation and rapid electron transfer, thereby enhancing the photocatalytic activity.

10.
J Exp Bot ; 2024 Aug 22.
Article de Anglais | MEDLINE | ID: mdl-39171750

RÉSUMÉ

Amino acid homeostasis is interconnected with the immune network of plants. During plant-pathogen interaction, amino acid transporters (AATs) have been shown to be involved in plant immune responses. However, the molecular mechanism by which how AATs function in this process remains elusive. In this study, we identify OsMP1 that acts as a quantitative trait locus against blast fungus from a joint analysis of GWAS and QTL mapping in rice. Heterogeneous expression of OsMP1 in yeast supports its function in transporting a wide range of amino acids, including Thr, Ser, Phe, His and Glu. OsMP1 could also mediate 15N-Glu efflux and influx in Xenopus oocyte cells. The expression of OsMP1 is dramatically induced by Magnaporthe oryzae in the resistant landrace Heikezijing, while remaining unresponsive in the susceptible landrace Suyunuo. Overexpressing OsMP1 in Suyunuo enhances disease resistance to blast fungus and leaf-blight bacterium without yield penalty. Furthermore, the overexpression of OsMP1 leads to increased accumulation of Thr, Ser, Phe and His in the leaves. And the heightened levels of these amino acids contribute to reduced disease susceptibility, which is associated with upregulated jasmonic acid pathway. Thus, our results elucidate the pivotal role of OsMP1 in disease resistance and provide a potential target for breeding more resistant rice cultivars without compromising yield.

11.
ChemSusChem ; : e202401500, 2024 Aug 24.
Article de Anglais | MEDLINE | ID: mdl-39180755

RÉSUMÉ

To mitigate the greenhouse effect, a number of porous organic polymers (POPs) has been developed for carbon capture. Considering the permanent quadrupole of symmetrical CO2 molecules, the integration of electron-rich groups into POPs is a feasible way to enhance the dipole-quadrupole interactions between host and guest. To comprehensively explore the effect of pore environment, including specific surface area, pore size, and number of heteroatoms, on carbon dioxide adsorption capacity, we synthesized a series of microporous POPs with different content of ß-ketoenamine structures via Schiff-base condensation reactions. These materials exhibit high BET specific surface areas, high stability, and excellent CO2 adsorption capacity. It is worth mentioning that the CO2 adsorption capacity and CO2/N2 selectivity of TAPPy-TFP reaches 3.87 mmol g-1 and 27. This work demonstrates that the introduction of ß-ketoenamine sites directly through condensation reaction is an effective strategy to improve the carbon dioxide adsorption performance of carbon dioxide.

12.
J Immunother Cancer ; 12(8)2024 Aug 06.
Article de Anglais | MEDLINE | ID: mdl-39107131

RÉSUMÉ

BACKGROUND: Checkpoint inhibitor therapy has demonstrated overall survival benefit in multiple tumor types. Tumor mutational burden (TMB) is a predictive biomarker for response to immunotherapies. This study evaluated the efficacy of nivolumab+ipilimumab in multiple tumor types based on TMB status evaluated using either tumor tissue (tTMB) or circulating tumor DNA in the blood (bTMB). PATIENTS AND METHODS: Patients with metastatic or unresectable solid tumors with high (≥10 mutations per megabase) tTMB (tTMB-H) and/or bTMB (bTMB-H) who were refractory to standard therapies were randomized 2:1 to receive nivolumab+ipilimumab or nivolumab monotherapy in an open-label, phase 2 study (CheckMate 848; NCT03668119). tTMB and bTMB were determined by the Foundation Medicine FoundationOne® CDx test and bTMB Clinical Trial Assay, respectively. The dual primary endpoints were objective response rate (ORR) in patients with tTMB-H and/or bTMB-H tumors treated with nivolumab+ipilimumab. RESULTS: In total, 201 patients refractory to standard therapies were randomized: 135 had tTMB-H and 125 had bTMB-H; 82 patients had dual tTMB-H/bTMB-H. In patients with tTMB-H, ORR was 38.6% (95% CI 28.4% to 49.6%) with nivolumab+ipilimumab and 29.8% (95% CI 17.3% to 44.9%) with nivolumab monotherapy. In patients with bTMB-H, ORR was 22.5% (95% CI 13.9% to 33.2%) with nivolumab+ipilimumab and 15.6% (95% CI 6.5% to 29.5%) with nivolumab monotherapy. Early and durable responses to treatment with nivolumab+ipilimumab were seen in patients with tTMB-H or bTMB-H. The safety profile of nivolumab+ipilimumab was manageable, with no new safety signals. CONCLUSIONS: Patients with metastatic or unresectable solid tumors with TMB-H, as determined by tissue biopsy or by blood sample when tissue biopsy is unavailable, who have no other treatment options, may benefit from nivolumab+ipilimumab. TRIAL REGISTRATION NUMBER: NCT03668119.


Sujet(s)
Protocoles de polychimiothérapie antinéoplasique , Ipilimumab , Tumeurs , Nivolumab , Humains , Nivolumab/usage thérapeutique , Nivolumab/administration et posologie , Nivolumab/pharmacologie , Femelle , Ipilimumab/usage thérapeutique , Ipilimumab/administration et posologie , Ipilimumab/pharmacologie , Mâle , Tumeurs/traitement médicamenteux , Tumeurs/génétique , Adulte d'âge moyen , Sujet âgé , Protocoles de polychimiothérapie antinéoplasique/usage thérapeutique , Adulte , Mutation , Sujet âgé de 80 ans ou plus , Métastase tumorale
13.
Angew Chem Int Ed Engl ; : e202411188, 2024 Jul 08.
Article de Anglais | MEDLINE | ID: mdl-38975980

RÉSUMÉ

Electrocatalytic carbon dioxide reduction reaction (CO2RR) is an effective way of converting CO2 into value-added products using renewable energy, whose activity and selectivity can be in principle maneuvered by tuning the microenvironment near catalytic sites. Here, we demonstrate a strategy for tuning the microenvironment of CO2RR by learning from the natural chlorophyll and heme. Specifically, the conductive covalent organic frameworks (COFs) linked by piperazine serve as versatile supports for single-atom catalysts (SACs), and the pendant groups modified on the COFs can be readily tailored to offer different push-pull electronic effects for tunable microenvironment. As a result, while all the COFs exhibit high chemical structure stability under harsh conditions and good conductivity, the addition of -CH2NH2 can greatly enhance the activity and selectivity of CO2RR. As proven by experimental characterization and theoretical simulation, the electron-donating group (-CH2NH2) not only reduces the surface work function of COF, but also improves the adsorption energy of the key intermediate *COOH, compared with the COFs with electron-withdrawing groups (-CN, -COOH) near the active sites. This work provides insights into the microenvironment modulation of CO2RR electrocatalysts at the molecular level.

14.
J Am Chem Soc ; 146(29): 19680-19685, 2024 Jul 24.
Article de Anglais | MEDLINE | ID: mdl-38979969

RÉSUMÉ

The pore shapes of two-dimensional covalent organic frameworks (2D COFs) significantly limit their practical applications in separation and catalysis. Although various 2D COFs with polygonal pores have been well developed, constructing COFs with pentagonal pores remains an enormous challenge. In this work, we developed one kind of pentagonal COFs with the mcm topological structure for the first time, through the rational combination of C4 and C2 symmetric building blocks. The resulting pentagonal COFs exhibit high crystallinity, excellent porosity, and strong robustness. Moreover, the inbuilt porphyrin units render these COFs as efficient electrocatalytic catalysts toward oxygen reduction reaction with a half-wave potential of up to 0.81 V, which ranks as one of the highest values among COFs-based electrocatalysts. This work not only verified the possibility of constructing 2D COFs with pentagonal pores but also developed a strategy for the construction of functional 2D COFs for interesting applications.

15.
Heliyon ; 10(13): e33652, 2024 Jul 15.
Article de Anglais | MEDLINE | ID: mdl-39040341

RÉSUMÉ

Soil freeze-thaw processes and snowmelt infiltration have a significant impact on the hydrological cycle and ecosystem productivity in alpine pastoral areas. To investigate the driving mechanism of snow on soil freeze-thaw processes, a meteorological station was established in the southern part of Namatso Lake, Tibet to collect environmental data. The study included analyzing the relationship between soil temperature and humity, as well as assessing soil freeze-thaw characteristics and the evolution of soil frost heave over time. The freeze-thaw frequency was significantly 43% lower at the surface soil, and the freeze-thaw intensity decreased when the ground was snow-covered. During the initial freezing period, precipitation and soil humidity remain relatively low, and soil moisture decreases linearly with decreasing soil temperature, which occurs in the phenomenon of soil freeze-shrink. During the initial thawing period, snowmelt infiltration impacts soil humidity, and soil frost heave increases logarithmically, reaching a maximum of 5.2 mm, driven by freeze-thaw. Soil moisture decreases under topsoil evaporation in the later stage and again follows a linear trend with the soil temperature. This study not only reveals the correlation between soil temperature and humidity during different freeze-thaw periods but also enhances the understanding of soil deformation patterns under the influence of snow accumulation.

16.
Cell ; 187(17): 4733-4750.e26, 2024 Aug 22.
Article de Anglais | MEDLINE | ID: mdl-38971152

RÉSUMÉ

We identify a population of Protogenin-positive (PRTG+ve) MYChigh NESTINlow stem cells in the four-week-old human embryonic hindbrain that subsequently localizes to the ventricular zone of the rhombic lip (RLVZ). Oncogenic transformation of early Prtg+ve rhombic lip stem cells initiates group 3 medulloblastoma (Gr3-MB)-like tumors. PRTG+ve stem cells grow adjacent to a human-specific interposed vascular plexus in the RLVZ, a phenotype that is recapitulated in Gr3-MB but not in other types of medulloblastoma. Co-culture of Gr3-MB with endothelial cells promotes tumor stem cell growth, with the endothelial cells adopting an immature phenotype. Targeting the PRTGhigh compartment of Gr3-MB in vivo using either the diphtheria toxin system or chimeric antigen receptor T cells constitutes effective therapy. Human Gr3-MBs likely arise from early embryonic RLVZ PRTG+ve stem cells inhabiting a specific perivascular niche. Targeting the PRTGhigh compartment and/or the perivascular niche represents an approach to treat children with Gr3-MB.


Sujet(s)
Médulloblastome , Cellules souches tumorales , Humains , Médulloblastome/anatomopathologie , Médulloblastome/métabolisme , Animaux , Cellules souches tumorales/métabolisme , Cellules souches tumorales/anatomopathologie , Souris , Rhombencéphale/métabolisme , Rhombencéphale/embryologie , Tumeurs du cervelet/métabolisme , Tumeurs du cervelet/anatomopathologie , Cellules endothéliales/métabolisme , Niche de cellules souches , Cellules souches/métabolisme , Techniques de coculture , Structures de l'embryon , Métencéphale/embryologie
17.
Ann Surg Oncol ; 31(9): 6320-6330, 2024 Sep.
Article de Anglais | MEDLINE | ID: mdl-38985229

RÉSUMÉ

BACKGROUND: Colorectal cancer (CRC) patients with mismatch repair-deficient/microsatellite instability-high (dMMR/MSI-H) status are conventionally perceived as unresponsive to adjuvant chemotherapy (ACT). The mitochondrial transcription factor A (TFAM) is required for mitochondrial DNA copy number (mtDNA-CN) expression. In light of previous findings indicating that the frequent truncating-mutation of TFAM affects the chemotherapy resistance of MSI CRC cells, this study aimed to explore the potential of mtDNA-CN as a predictive biomarker for ACT efficacy in dMMR CRC patients. METHODS: Levels of MtDNA-CN were assessed using quantitative real-time polymerase chain reaction (qRT-PCR) in a cohort of 308 CRC patients with dMMR comprising 180 stage II and 128 stage III patients. Clinicopathologic and therapeutic data were collected. The study examined the association between mtDNA-CN levels and prognosis, as well as the impact of ACT benefit on dMMR CRC patients. Subgroup analyses were performed based mainly on tumor stage and mtDNA-CN level. Kaplan-Meier and Cox regression models were used to evaluate the effect of mtDNA-CN on disease-free survival (DFS) and overall survival (OS). RESULTS: A substantial reduction in mtDNA-CN expression was observed in tumor tissue, and higher mtDNA-CN levels were correlated with improved DFS (73.4% vs 85.7%; P = 0.0055) and OS (82.5% vs 90.3%; P = 0.0366) in dMMR CRC patients. Cox regression analysis identified high mtDNA-CN as an independent protective factor for DFS (hazard ratio [HR] 0.547; 95% confidence interval [CI] 0.321-0.934; P = 0.0270) and OS (HR 0.520; 95% CI 0.272-0.998; P = 0.0492). Notably, for dMMR CRC patients with elevated mtDNA-CN, ACT significantly improved DFS (74.6% vs 93.4%; P = 0.0015) and OS (81.0% vs 96.7%; P = 0.0017), including those with stage II or III disease. CONCLUSIONS: The mtDNA-CN levels exhibited a correlation with the prognosis of stage II or III CRC patients with dMMR. Elevated mtDNA-CN emerges as a robust prognostic factor, indicating improved ACT outcomes for stages II and III CRC patients with dMMR. These findings suggest the potential utility of mtDNA-CN as a biomarker for guiding personalized ACT treatment in this population.


Sujet(s)
Marqueurs biologiques tumoraux , Tumeurs colorectales , Variations de nombre de copies de segment d'ADN , Réparation de mésappariement de l'ADN , ADN mitochondrial , Instabilité des microsatellites , Stadification tumorale , Humains , Tumeurs colorectales/anatomopathologie , Tumeurs colorectales/génétique , Tumeurs colorectales/traitement médicamenteux , ADN mitochondrial/génétique , Femelle , Mâle , Traitement médicamenteux adjuvant , Marqueurs biologiques tumoraux/génétique , Marqueurs biologiques tumoraux/métabolisme , Adulte d'âge moyen , Pronostic , Taux de survie , Sujet âgé , Études de suivi , Protocoles de polychimiothérapie antinéoplasique/usage thérapeutique , Adulte
18.
Int Immunopharmacol ; 138: 112634, 2024 Sep 10.
Article de Anglais | MEDLINE | ID: mdl-38971107

RÉSUMÉ

Metabolic dysfunction-associated steatohepatitis (MASH) is a severe metabolic dysfunction-associated steatotic liver disease (MASLD) characterized by abnormal hepatic steatosis and inflammation. Previous studies have shown that Patchouli alcohol (PA), the primary component of Pogostemonis Herba, can alleviate digestive system diseases. However, its protection against MASH remains unclear. This study explored the protective effects and underlying mechanism of PA against high-fat diet-induced MASH in rats. Results showed that PA considerably reduced body weight, epididymal fat, and liver index and attenuated liver histological injury in MASH rats. PA alleviated hepatic injury by inhibiting steatosis and inflammation. These effects are associated with the improvement of SREBP-1c- and PPARα-mediated lipid metabolism and inhibition of the STING-signaling pathway-mediated inflammatory response. Moreover, PA-inhibited hepatic endoplasmic reticulum (ER) stress and mitochondrial dysfunction, reducing SREBP-1c and STING expressions and enhance PPARα expression. PA treatment had the strongest effect on the regulation of mitogen fusion protein 2 (Mfn2) in inhibiting mitochondrial dysfunction. Mfn2 is an important structural protein for binding ERs and mitochondria to form mitochondria-associated ER membranes (MAMs). MASH-mediated disruption of MAMs was inhibited after PA treatment-induced Mfn2 activation. Therefore, the pharmacological effect of PA on MASH is mainly attributed to the inhibition of MAM disruption-induced hepatic steatosis and inflammation. The findings of this study may have implications for MASH treatment that do not neglect the role of Mfn2-mediated MAMs.


Sujet(s)
Alimentation riche en graisse , Stress du réticulum endoplasmique , Réticulum endoplasmique , Récepteur PPAR alpha , Rat Sprague-Dawley , Sesquiterpènes , Animaux , Mâle , Réticulum endoplasmique/métabolisme , Réticulum endoplasmique/effets des médicaments et des substances chimiques , Alimentation riche en graisse/effets indésirables , Rats , Sesquiterpènes/usage thérapeutique , Sesquiterpènes/pharmacologie , Récepteur PPAR alpha/métabolisme , Stress du réticulum endoplasmique/effets des médicaments et des substances chimiques , Foie/anatomopathologie , Foie/effets des médicaments et des substances chimiques , Foie/métabolisme , Mitochondries/effets des médicaments et des substances chimiques , Mitochondries/métabolisme , Stéatose hépatique/traitement médicamenteux , Stéatose hépatique/métabolisme , Stéatose hépatique/anatomopathologie , Protéine-1 de liaison à l'élément de régulation des stérols/métabolisme , Protéine-1 de liaison à l'élément de régulation des stérols/génétique , Métabolisme lipidique/effets des médicaments et des substances chimiques , Anti-inflammatoires/usage thérapeutique , Anti-inflammatoires/pharmacologie , Inflammation/traitement médicamenteux , Pogostemon , Transduction du signal/effets des médicaments et des substances chimiques
19.
Elife ; 132024 Jul 09.
Article de Anglais | MEDLINE | ID: mdl-38980810

RÉSUMÉ

Background: Diffuse large B-cell lymphoma (DLBCL) is the predominant type of malignant B-cell lymphoma. Although various treatments have been developed, the limited efficacy calls for more and further exploration of its characteristics. Methods: Datasets from the Gene Expression Omnibus (GEO) database were used for identifying the tumor purity of DLBCL. Survival analysis was employed for analyzing the prognosis of DLBCL patients. Immunohistochemistry was conducted to detect the important factors that influenced the prognosis. Drug-sensitive prediction was performed to evaluate the value of the model. Results: VCAN, CD3G, and C1QB were identified as three key genes that impacted the outcome of DLBCL patients both in GEO datasets and samples from our center. Among them, VCAN and CD3G+ T cells were correlated with favorable prognosis, and C1QB was correlated with worse prognosis. The ratio of CD68 + macrophages and CD8 + T cells was associated with better prognosis. In addition, CD3G+T cells ratio was significantly correlated with CD68 + macrophages, CD4 + T cells, and CD8 +T cells ratio, indicating it could play an important role in the anti-tumor immunity in DLBCL. The riskScore model constructed based on the RNASeq data of VCAN, C1QB, and CD3G work well in predicting the prognosis and drug sensitivity. Conclusions: VCAN, CD3G, and C1QB were three key genes that influenced the tumor purity of DLBCL, and could also exert certain impact on drug sensitivity and prognosis of DLBCL patients. Funding: This work is supported by the Shenzhen High-level Hospital Construction Fund and CAMS Innovation Fund for Medical Sciences (CIFMS) (2022-I2M-C&T-B-062).


Sujet(s)
Lymphome B diffus à grandes cellules , Humains , Lymphome B diffus à grandes cellules/génétique , Lymphome B diffus à grandes cellules/traitement médicamenteux , Lymphome B diffus à grandes cellules/mortalité , Lymphome B diffus à grandes cellules/immunologie , Pronostic , Femelle , Mâle , Marqueurs biologiques tumoraux/génétique , Marqueurs biologiques tumoraux/métabolisme , Résistance aux médicaments antinéoplasiques/génétique , Régulation de l'expression des gènes tumoraux , Adulte d'âge moyen , Analyse de survie
20.
Angew Chem Int Ed Engl ; : e202411806, 2024 Jul 10.
Article de Anglais | MEDLINE | ID: mdl-38988007

RÉSUMÉ

Covalent organic frameworks are a class of crystalline porous polymers formed by linking organic units into periodically aligned skeletons and pores. Here we report a strategy for wiring these frameworks with conducting polymers via wall engineering and polymerization. We anchored each edge site with one pyrrole unit, which is densely packed along the z direction yet protruded from pore walls. This assembly enables the polymerization of pyrrole units to form polypyrrole and creates a new polypyrrole chain conformation. The resultant framework constitutes six single file polypyrrole chains in each pore and develop spatially segregated yet built-in single molecular wires with exceptional stable polarons. Hall effect measurements revealed that the materials are p-type semiconductors, increase conductivity by eight orders of magnitude compared to the pristine frameworks, and achieve a carrier mobility as large as 13.2 cm2 V-1 s-1. Our results open an avenue to π electronic frameworks by interlayer molecular wiring with conducting polymers.

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