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1.
Cell ; 176(1-2): 334-347.e12, 2019 01 10.
Article in English | MEDLINE | ID: mdl-30580966

ABSTRACT

Lymphocyte-activation gene 3 (LAG-3) is an immune inhibitory receptor, with major histocompatibility complex class II (MHC-II) as a canonical ligand. However, it remains controversial whether MHC-II is solely responsible for the inhibitory function of LAG-3. Here, we demonstrate that fibrinogen-like protein 1 (FGL1), a liver-secreted protein, is a major LAG-3 functional ligand independent from MHC-II. FGL1 inhibits antigen-specific T cell activation, and ablation of FGL1 in mice promotes T cell immunity. Blockade of the FGL1-LAG-3 interaction by monoclonal antibodies stimulates tumor immunity and is therapeutic against established mouse tumors in a receptor-ligand inter-dependent manner. FGL1 is highly produced by human cancer cells, and elevated FGL1 in the plasma of cancer patients is associated with a poor prognosis and resistance to anti-PD-1/B7-H1 therapy. Our findings reveal an immune evasion mechanism and have implications for the design of cancer immunotherapy.


Subject(s)
Antigens, CD/metabolism , Neoplasm Proteins/metabolism , Neoplasm Proteins/physiology , Animals , Antigens, CD/immunology , Cell Line , Fibrinogen/immunology , Fibrinogen/metabolism , Genes, MHC Class II/genetics , Genes, MHC Class II/immunology , Histocompatibility Antigens Class II/genetics , Histocompatibility Antigens Class II/immunology , Histocompatibility Antigens Class II/metabolism , Humans , Immunotherapy , Ligands , Liver/metabolism , Lymphocyte Activation/immunology , Mice , Mice, Inbred C57BL , Mice, Knockout , Neoplasm Proteins/genetics , Neoplasms/immunology , T-Lymphocytes, Cytotoxic/immunology , Lymphocyte Activation Gene 3 Protein
2.
Mol Cell ; 84(9): 1711-1726.e11, 2024 May 02.
Article in English | MEDLINE | ID: mdl-38569554

ABSTRACT

N6-methyladenosine (m6A) is a crucial RNA modification that regulates diverse biological processes in human cells, but its co-transcriptional deposition and functions remain poorly understood. Here, we identified the RNA helicase DDX21 with a previously unrecognized role in directing m6A modification on nascent RNA for co-transcriptional regulation. DDX21 interacts with METTL3 for co-recruitment to chromatin through its recognition of R-loops, which can be formed co-transcriptionally as nascent transcripts hybridize onto the template DNA strand. Moreover, DDX21's helicase activity is needed for METTL3-mediated m6A deposition onto nascent RNA following recruitment. At transcription termination regions, this nexus of actions promotes XRN2-mediated termination of RNAPII transcription. Disruption of any of these steps, including the loss of DDX21, METTL3, or their enzymatic activities, leads to defective termination that can induce DNA damage. Therefore, we propose that the R-loop-DDX21-METTL3 nexus forges the missing link for co-transcriptional modification of m6A, coordinating transcription termination and genome stability.


Subject(s)
Adenosine , Adenosine/analogs & derivatives , DEAD-box RNA Helicases , Exoribonucleases , Genomic Instability , Methyltransferases , R-Loop Structures , RNA Polymerase II , Transcription Termination, Genetic , Humans , DEAD-box RNA Helicases/metabolism , DEAD-box RNA Helicases/genetics , Methyltransferases/metabolism , Methyltransferases/genetics , Adenosine/metabolism , Adenosine/genetics , Exoribonucleases/metabolism , Exoribonucleases/genetics , RNA Polymerase II/metabolism , RNA Polymerase II/genetics , HEK293 Cells , Chromatin/metabolism , Chromatin/genetics , DNA Damage , HeLa Cells , RNA/metabolism , RNA/genetics , Transcription, Genetic , RNA Methylation
3.
Nature ; 612(7938): 72-77, 2022 12.
Article in English | MEDLINE | ID: mdl-36352229

ABSTRACT

Advancements in many modern technologies rely on the continuous need for materials discovery. However, the design of synthesis routes leading to new and targeted solid-state materials requires understanding of reactivity patterns1-3. Advances in synthesis science are necessary to increase efficiency and accelerate materials discovery4-10. We present a highly effective methodology for the rational discovery of materials using high-temperature solutions or fluxes having tunable solubility. This methodology facilitates product selection by projecting the free-energy landscape into real synthetic variables: temperature and flux ratio. We demonstrate the effectiveness of this technique by synthesizing compounds in the chalcogenide system of A(Ba)-Cu-Q(O) (Q = S or Se; A = Na, K or Rb) using mixed AOH/AX (A = Li, Na, K or Rb; X = Cl or I) fluxes. We present 30 unreported compounds or compositions, including more than ten unique structural types, by systematically varying the temperature and flux ratios without requiring changing the proportions of starting materials. Also, we found that the structural dimensionality of the compounds decreases with increasing reactant solubility and temperature. This methodology serves as an effective general strategy for the rational discovery of inorganic solids.

4.
Mol Cell ; 75(6): 1188-1202.e11, 2019 09 19.
Article in English | MEDLINE | ID: mdl-31399345

ABSTRACT

The maternal-to-zygotic transition (MZT) is a conserved and fundamental process during which the maternal environment is converted to an environment of embryonic-driven development through dramatic reprogramming. However, how maternally supplied transcripts are dynamically regulated during MZT remains largely unknown. Herein, through genome-wide profiling of RNA 5-methylcytosine (m5C) modification in zebrafish early embryos, we found that m5C-modified maternal mRNAs display higher stability than non-m5C-modified mRNAs during MZT. We discovered that Y-box binding protein 1 (Ybx1) preferentially recognizes m5C-modified mRNAs through π-π interactions with a key residue, Trp45, in Ybx1's cold shock domain (CSD), which plays essential roles in maternal mRNA stability and early embryogenesis of zebrafish. Together with the mRNA stabilizer Pabpc1a, Ybx1 promotes the stability of its target mRNAs in an m5C-dependent manner. Our study demonstrates an unexpected mechanism of RNA m5C-regulated maternal mRNA stabilization during zebrafish MZT, highlighting the critical role of m5C mRNA modification in early development.


Subject(s)
5-Methylcytosine/metabolism , Embryo, Nonmammalian/embryology , Embryonic Development/physiology , RNA Stability/physiology , RNA, Messenger, Stored/metabolism , Zebrafish/embryology , Animals , HeLa Cells , Humans , Mice , RNA, Messenger, Stored/genetics , Zebrafish/genetics
5.
Cancer Immunol Immunother ; 73(4): 61, 2024 Mar 02.
Article in English | MEDLINE | ID: mdl-38430267

ABSTRACT

BACKGROUND: Recent progressions in CAR-T cell therapy against pancreatic ductal adenocarcinoma (PDAC) remain disappointing, which are partially attributed to the immunosuppressive microenvironment including macrophage-mediated T cell repletion. METHODS: We first characterized the expression patterns of macrophage-relevant chemokines and identified CXCR2 as the key factor regulating T cell trafficking and tumor-specific accumulation in PDAC microenvironment. After that, we synthesized and introduced a CXCR2 expression cascade into Claudin18.2 CAR-T cells and compared the behaviors of CAR-T cells in vitro and in vivo. The therapeutic potential of CXCR2 CAR-T was evaluated in two different allogeneic models: subcutaneous allografts and metastatic PDAC models. RESULTS: The results showed that CXCR2 CAR-T not only reduced the size of allografted PDAC tumors, but also completely eliminated the formation of metastases. Lastly, we investigated the tumor tissues and found that expression of ectopic CXCR2 significantly improved tumor-targeted infiltration and residence of T cells and reduced the presence of MDSCs and CXCR2 + macrophages in PDAC microenvironment. CONCLUSION: Our studies suggested that ectopic CXCR2 played a significant and promising role in improving the efficiency of CAR-T therapy against primary and metastatic PDAC and partially reversed the immune-suppressive microenvironment.


Subject(s)
Adenocarcinoma , Carcinoma, Pancreatic Ductal , Pancreatic Neoplasms , Receptors, Chimeric Antigen , Humans , Pancreatic Neoplasms/therapy , Carcinoma, Pancreatic Ductal/therapy , Disease Progression , Tumor Microenvironment
6.
Opt Express ; 32(11): 20092-20108, 2024 May 20.
Article in English | MEDLINE | ID: mdl-38859126

ABSTRACT

This paper introduces a new plenoptic 3D particle tracking velocimetry (3D-PTV) technique called raw-image ray-bundling (RIRB), which combines the 3D clustering algorithm of light-field ray-bundling (LFRB) with the raw image segmentation concept of epipolar triangular connectivity (ETC). The combined approach provides flexibility towards accommodating both unfocused and focused plenoptic cameras. Additionally, the RIRB algorithm bypasses the computational step of perspective-view generation in LFRB, thereby allowing lower specification microlens arrays (MLA) to be used without excessive loss of measurement resolution. As part of RIRB's development, synthetic particle-field data and experimental dot-panel targets were used to demonstrate the viability of RIRB. The latter was performed through a VEO640 high-speed camera retrofitted for plenoptic imaging with a 2.5 mm focal-length, F/10 MLA. For the synthetic dataset, RIRB demonstrated better performance than LFRB in processing low-resolution images, with mean errors below 0.85% of the field-of-view (FOV). Additionally, a synthetic Hagen-Poiseuille flow dataset was used to demonstrate the feasibility of RIRB for 3D flow velocimetry using both high and low-resolution images. For the experimental dataset, x/y errors below 0.15% of the FOV and z error below 1.0% were achieved. The combination of synthetic and experimental validations suggests RIRB is a promising approach for 3D triangulation from both focused and unfocused raw plenoptic images, overcoming the low-resolution issue inherent with perspective-view decoding in plenoptic systems.

7.
Phys Rev Lett ; 132(15): 156701, 2024 Apr 12.
Article in English | MEDLINE | ID: mdl-38682975

ABSTRACT

A new perovskite KOsO_{3} has been stabilized under high-pressure and high-temperature conditions. It is cubic at 500 K (Pm-3m) and undergoes subsequent phase transitions to tetragonal at 320 K (P4/mmm) and rhombohedral (R-3m) at 230 K as shown from refining synchrotron x-ray powder diffraction (SXRD) data. The larger orbital overlap integral and the extended wave function of 5d electrons in the perovskite KOsO_{3} allow to explore physics from the regime where Mott and Hund's rule couplings dominate to the state where the multiple interactions are on equal footing. We demonstrate an exotic magnetic ordering phase found by neutron powder diffraction along with physical properties via a suite of measurements including magnetic and transport properties, differential scanning calorimetry, and specific heat, which provide comprehensive information for a system at the crossover from localized to itinerant electronic behavior.

8.
Anticancer Drugs ; 35(1): 93-96, 2024 01 01.
Article in English | MEDLINE | ID: mdl-37449979

ABSTRACT

Third-generation EGFR-TKIs can be used to treat advanced non-small cell lung cancer patients with T790M resistance mutation induced by first- or second-generation EGFR-TKIs. However, it will also result in drug resistance, and the resistance mechanisms of third-generation EGFR-TKIs are complex. Here we reported a patient diagnosed with advanced lung adenocarcinoma and EGFR positive in September 2016. Following first-line targeted therapy with gefitinib, genetic testing showed EGFR T790M positive, which resulted in a change to osimertinib targeted therapy. In May 2021, troponin and creatinine levels were elevated, and the tumor hyperprogressed to severe lung cancer. Repeated genetic testing revealed that EGFR genotype converted to a non-classical mutation and EGFR T790M turned negative, which caused third-generation EGFR-TKI resistance. As a result, afatinib combined with anlotinib was selected to stabilize the patient's condition. We were inspired by the case that it reflects the significance and necessity of exploring the resistance mechanism and dynamically detecting genetic status throughout the course of treatment, which may help realize individualized precision therapy, and maximize the potential of patient.


Subject(s)
Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Humans , Lung Neoplasms/drug therapy , Lung Neoplasms/genetics , Lung Neoplasms/pathology , Afatinib/therapeutic use , Carcinoma, Non-Small-Cell Lung/drug therapy , Carcinoma, Non-Small-Cell Lung/genetics , Carcinoma, Non-Small-Cell Lung/pathology , ErbB Receptors/genetics , Protein Kinase Inhibitors/therapeutic use , Protein Kinase Inhibitors/pharmacology , Mutation , Drug Resistance, Neoplasm
9.
Br J Nutr ; : 1-28, 2024 Jun 04.
Article in English | MEDLINE | ID: mdl-38832664

ABSTRACT

Achieving optimal nutritional status in patients with penetrating Crohn's disease (CD) is crucial in preparing for surgical resection. However, there is a dearth of literature comparing the efficacy of total parenteral nutrition (TPN) versus exclusive enteral nutrition (EEN) in optimizing postoperative outcomes. Hence, we conducted a case-matched study to assess the impact of preoperative EEN versus TPN on the incidence of postoperative adverse outcomes, encompassing overall postoperative morbidity and stoma formation, among penetrating CD patients undergoing bowel surgery. From December 1, 2012 to December 1, 2021, a retrospective study was conducted at a tertiary center to enroll consecutive patients with penetrating CD who underwent surgical resection. Propensity score matching (PSM) was utilized to compare the incidence of postoperative adverse outcomes. Furthermore, univariate and multivariate logistic regression analyses were conducted to identify the risk factors associated with adverse outcomes. The study included 510 patients meeting the criteria. Among them, 101 patients in the TPN group showed significant improvements in laboratory indicators at the time of surgery compared to pre-optimization levels. After matching, TPN was increased occurrence of postoperative adverse outcomes (92.2% vs. 64.1%, p = 0.001) when compared to EEN group. In the multivariate analysis, TPN showed a significantly higher odds ratio for adverse outcomes than EEN (OR = 4.241; 95% CI 1.567-11.478; p = 0.004). The study revealed that penetrating CD patients who were able to fulfill their nutritional requirements through EEN exhibited superior nutritional and surgical outcomes in comparison to those who received TPN.

10.
Scand J Gastroenterol ; 59(1): 39-45, 2024.
Article in English | MEDLINE | ID: mdl-37622924

ABSTRACT

BACKGROUND: Few studies have compared endoscopic balloon dilation (EBD) and surgery in the treatment of duodenal stricture in patients with Crohn's disease (CD). METHODS: We performed a retrospective study to compare the efficacy and safety among patients with CD-associated duodenal stricture treated with EBD or surgery from October 2013 to December 2021. Univariate and multivariate analyses were performed to evaluate factors associated with recurrence-free or surgery-free survival. RESULTS: A total of 48 eligible patients were included, including 30 patients treated with EBD only and 18 patients treated with surgery. Patients treated with surgery experienced more symptomatic improvement (100% vs. 63.33%, p = 0.003) and significantly longer recurrence-free survival (6.31 [IQR: 3.00-8.39] years vs. 2.96 [IQR: 1.06-5.42] years, p = 0.01) but suffered more postprocedural adverse events (16.67% vs. 0.74% per procedure, p = 0.001). In patients initially treated with EBD (n = 41), a total of 11 (26.83%) required subsequent surgical intervention. Younger age at CD diagnosis (HR = 0.90, 95% CI: 0.81-1.00, p = 0.04) was associated with a higher risk for subsequent surgery. CONCLUSIONS: Surgery for CD-associated duodenal strictures was associated with a longer recurrence-free survival. EBD was safe and effective with minimal postprocedural adverse events but led to a high frequency of recurrence.


Subject(s)
Crohn Disease , Intestinal Obstruction , Humans , Crohn Disease/surgery , Constriction, Pathologic/etiology , Constriction, Pathologic/surgery , Retrospective Studies , Dilatation/adverse effects , Intestinal Obstruction/etiology , Treatment Outcome , Endoscopy, Gastrointestinal/methods
11.
Mol Cell ; 61(4): 507-519, 2016 Feb 18.
Article in English | MEDLINE | ID: mdl-26876937

ABSTRACT

The regulatory role of N(6)-methyladenosine (m(6)A) and its nuclear binding protein YTHDC1 in pre-mRNA splicing remains an enigma. Here we show that YTHDC1 promotes exon inclusion in targeted mRNAs through recruiting pre-mRNA splicing factor SRSF3 (SRp20) while blocking SRSF10 (SRp38) mRNA binding. Transcriptome assay with PAR-CLIP-seq analysis revealed that YTHDC1-regulated exon-inclusion patterns were similar to those of SRSF3 but opposite of SRSF10. In vitro pull-down assay illustrated a competitive binding of SRSF3 and SRSF10 to YTHDC1. Moreover, YTHDC1 facilitates SRSF3 but represses SRSF10 in their nuclear speckle localization, RNA-binding affinity, and associated splicing events, dysregulation of which, as the result of YTHDC1 depletion, can be restored by reconstitution with wild-type, but not m(6)A-binding-defective, YTHDC1. Our findings provide the direct evidence that m(6)A reader YTHDC1 regulates mRNA splicing through recruiting and modulating pre-mRNA splicing factors for their access to the binding regions of targeted mRNAs.


Subject(s)
Cell Cycle Proteins/metabolism , Nerve Tissue Proteins/metabolism , RNA Splicing , RNA-Binding Proteins/metabolism , Repressor Proteins/metabolism , Adenosine/analogs & derivatives , Adenosine/metabolism , Binding Sites , Exons , HeLa Cells , Humans , RNA Splicing Factors , RNA, Messenger/metabolism , Serine-Arginine Splicing Factors
12.
Appl Opt ; 63(10): 2503-2508, 2024 Apr 01.
Article in English | MEDLINE | ID: mdl-38568529

ABSTRACT

We propose a methodology to mitigate angular color variation in full-color micron-scale LED arrays. By simulating light field distribution for red (AlGaAs) and green/blue (GaN) light across various RGB micro-LED sizes, we can select matching light field patterns for RGB chips, reducing angular color variation from 0.0201 to 0.0030. Applying this method to full-color mini-LED assemblies achieves a reduction from 0.0128 to 0.0032 by matching light field patterns with varying substrate thicknesses. This straightforward approach aligns with current mass transfer processes, offering practical implementation.

13.
J Am Chem Soc ; 145(6): 3491-3498, 2023 02 15.
Article in English | MEDLINE | ID: mdl-36749207

ABSTRACT

Class Ic ribonucleotide reductases (RNRIc) and R2-like ligand-binding oxidases (R2lox) are known to contain heterobimetallic MnIIFeII cofactors. How these enzymes assemble MnIIFeII cofactors has been a long-standing puzzle due to the weaker binding affinity of MnII versus FeII. In addition, the heterobimetallic selectivity of RNRIc and R2lox has yet to be reproduced with coordination complexes, leading to the hypothesis that RNRIc and R2lox overcome the thermodynamic preference for coordination of FeII over MnII with their carefully constructed three-dimensional protein structures. Herein, we report the selective formation of a heterobimetallic MnIIFeII complex accomplished in the absence of a protein scaffold. Treatment of the ligand Py4DMcT (L) with equimolar amounts of FeII and MnII along with two equivalents of acetate (OAc) affords [LMnIIFeII (OAc)2(OTf)]+ (MnIIFeII) in 80% yield, while the diiron complex [LFeIIFeII(OAc)2(OTf)]+ (FeIIFeII) is produced in only 8% yield. The formation of MnIIFeII is favored regardless of the order of addition of FeII and MnII sources. X-ray diffraction (XRD) of single crystals of MnIIFeII reveals an unsymmetrically coordinated carboxylate ligand─a primary coordination sphere feature shared by both RNRIc and R2lox that differentiates the two metal binding sites. Anomalous XRD studies confirm that MnIIFeII exhibits the same site selectivity as R2lox and RNRIc, with the FeII (d6) center preferentially occupying the distorted octahedral site. We conclude that the successful assembly of MnIIFeII originates from (1) Fe-deficient conditions, (2) site differentiation, and (3) the inability of ligand L to house a dimanganese complex.


Subject(s)
Iron , Ribonucleotide Reductases , Iron/chemistry , Ligands , Oxidoreductases/metabolism , Ribonucleotide Reductases/chemistry , Ferrous Compounds
14.
Chemistry ; 29(41): e202300899, 2023 Jul 20.
Article in English | MEDLINE | ID: mdl-37156722

ABSTRACT

The supramolecular recognition of anions is increasingly harnessed to achieve the self-assembly of supramolecular architectures, ranging from cages and polymers to (pseudo)rotaxanes. The cyanostar (CS) macrocycle has previously been shown to form 2 : 1 complexes with organophosphate anions that can be turned into [3]rotaxanes by stoppering. Here we achieved steric control over the assembly of pseudorotaxanes comprising the cyanostar macrocycle and a thread that is based, for the first time, on organo-pyrophosphonates. Subtle differences in steric bulk on the threads allowed formation of either [3]pseudorotaxanes or [2]pseudorotaxanes. We demonstrate that the threading kinetics are governed by the steric demand of the organo-pyrophosphonates and in one case, slows down to the timescale of minutes. Calculations show that the dianions are sterically offset inside the macrocycles. Our findings broaden the scope of cyanostar-anion assemblies and may have relevance for the design of molecular machines whose directionality is a result of relatively slow slipping.

15.
Chemistry ; 29(59): e202301389, 2023 Oct 23.
Article in English | MEDLINE | ID: mdl-37498734

ABSTRACT

Organofunctionalized tetranuclear clusters [(MII Cl)2 (VIV O)2 {((HOCH2 CH2 )(H)N(CH2 CH2 O))(HN(CH2 CH2 O)2 )}2 ] (1, M=Co, 2: M=Zn) containing an unprecedented oxometallacyclic {M2 V2 Cl2 N4 O8 } (M=Co, Zn) framework have been prepared by solvothermal reactions. The new oxo-alkoxide compounds were fully characterized by spectroscopic methods, magnetic susceptibility measurement, DFT and ab initio computational methods, and complete single-crystal X-ray diffraction structure analysis. The isostructural clusters are formed of edge-sharing octahedral {VO5 N} and trigonal bipyramidal {MO3 NCl} units. Diethanolamine ligates the bimetallic lacunary double cubane core of 1 and 2 in an unusual two-mode fashion, unobserved previously. In the crystalline state, the clusters of 1 and 2 are joined by hydrogen bonds to form a three-dimensional network structure. Magnetic susceptibility data indicate weakly antiferromagnetic interactions between the vanadium centers [Jiso (VIV -VIV )=-5.4(1); -3.9(2) cm-1 ], and inequivalent antiferromagnetic interactions between the cobalt and vanadium centers [Jiso (VIV -CoII )=-12.6 and -7.5 cm-1 ] contained in 1.

16.
BMC Cancer ; 23(1): 455, 2023 May 18.
Article in English | MEDLINE | ID: mdl-37202742

ABSTRACT

BACKGROUND: PVT1, a previously uncharacterized lncRNA, was identified as a critical regulator involved in multiple functions in tumor, including cell proliferation, cell motility, angiogenesis and so on. However, the clinical significance and underlying mechanism of PVT1 was not be fully explored in glioma. METHODS: In this study, 1210 glioma samples with transcriptome data from three independent databases (CGGA RNA-seq, TCGA RNA-seq and GSE16011 cohorts) were enrolled in this study. Clinical information and genomic profiles containing somatic mutations and DNA copy numbers were collected from TCGA cohort. The R software was performed for statistical calculations and graphics. Furthermore, we validated the function of PVT1 in vitro. RESULTS: The results indicated that higher PVT1 expression was associated with aggressive progression of glioma. Cases with higher PVT1 expression always accompanied by PTEN and EGFR alteration. In addition, functional analyses and western blot results suggested that PVT1 inhibited the sensitivity of TMZ chemotherapy via JAK/STAT signaling. Meanwhile, knockdown of PVT1 increased the sensitivity of TZM chemotherapy in vitro. Finally, high PVT1 expression was associated with reduced survival time and may serve as a strong prognostic indicator for gliomas. CONCLUSIONS: This study demonstrated that PVT1 expression strongly correlated with tumor progression and chemo-resistance. PVT1 may become a potential biomarker for the diagnosis and treatment in glioma.


Subject(s)
Drug Resistance, Neoplasm , Gene Expression Regulation, Neoplastic , Glioma , RNA, Long Noncoding , Temozolomide , RNA, Long Noncoding/genetics , RNA, Long Noncoding/metabolism , Temozolomide/pharmacology , Temozolomide/therapeutic use , Drug Resistance, Neoplasm/genetics , Gene Knockdown Techniques , Carcinogenesis/genetics , Gene Expression Regulation, Neoplastic/genetics , Glioma/drug therapy , Glioma/genetics , Glioma/physiopathology , Survival Analysis , STAT Transcription Factors/metabolism , Janus Kinases/metabolism , Cell Line, Tumor , Humans , Male , Female , Adult , Middle Aged , Biomarkers, Tumor/metabolism
17.
J Neurooncol ; 165(3): 487-497, 2023 Dec.
Article in English | MEDLINE | ID: mdl-38057505

ABSTRACT

PURPOSE: Spinal ependymoma (SE) is a rare tumor that is most commonly low-grade and tends to recur when complete tumor resection is not feasible. We investigated the molecular mechanism induces stem cell features in SE. METHODS: Immunohistochemical staining was conducted to analyze the expression of RFX2 in tumor tissues of SE patients at different stages. The expression of tumor stemness markers (Netsin and CD133) was analyzed using western blot analysis and IF, and the efficiency of sphere formation in SE cells was analyzed. The biological activities of SE cells were analyzed by EdU proliferation assay, TUNEL, wound healing, and Transwell assays. The regulatory relationship of RFX2 on PAF1 was verified by ChIP-qPCR and the dual-luciferase assay. SE cells were injected into the spinal cord of nude mice for in vivo assays. RESULTS: RFX2 was higher in the tumor tissues of SE-III patients than in the tumor tissues of SE-I patients. RFX2 knockdown reduced the expression of tumor stemness markers in SE cells and inhibited the sphere formation efficiency. Moreover, RFX2 knockdown ameliorated the malignant progression of SE in nude mice, as manifested by prolonged survival and alleviated SE tumor infiltration. RFX2 bound to the PAF1 promoter to induce its transcription. Overexpression of PAF1 overturned the effects of RFX2 knockdown on stem cell features and biological activities of SE cells, thereby reducing survival in mice. CONCLUSIONS: RFX2 activates PAF1 transcription, which promotes tumor stemness of SE cells and leads to the malignant progression of SE.


Subject(s)
Ependymoma , Epigenesis, Genetic , Humans , Animals , Mice , Mice, Nude , Cell Line, Tumor , Neoplasm Recurrence, Local/pathology , Ependymoma/pathology , Cell Proliferation , Gene Expression Regulation, Neoplastic , Neoplastic Stem Cells/pathology , Regulatory Factor X Transcription Factors/metabolism , Transcription Factors/genetics , Transcription Factors/metabolism
18.
Inorg Chem ; 62(37): 15267-15276, 2023 Sep 18.
Article in English | MEDLINE | ID: mdl-37651726

ABSTRACT

Studies of multinuclear metal complexes are greatly enhanced by resonant diffraction measurements, which probe X-ray absorption profiles of crystallographically independent metal sites within a cluster. In particular, X-ray diffraction anomalous fine structure (DAFS) analysis provides data that can be interpreted akin to site-specific XANES, allowing for differences in metal K-edge resonances to be deconvoluted even for different metal sites within a homometallic system. Despite the prevalence of Cu-containing clusters in biology and energy science, DAFS has yet to be used to analyze multicopper complexes of any type until now. Here, we report an evaluation of trends using a series of strategically chosen Cu(I) and Cu(II) complexes to determine how energy dependencies of anomalous scattering factors are impacted by coordination geometry, ligand shell, cluster nuclearity, and oxidation state. This calibration data is used to analyze a formally tricopper(I) complex that was found by DAFS to be site-differentiated due to the unsymmetrical influence on different Cu sites of the electrostatic field from a proximal K+ cation.

19.
BMC Gastroenterol ; 23(1): 113, 2023 Apr 06.
Article in English | MEDLINE | ID: mdl-37024802

ABSTRACT

BACKGROUND: Pancreatic adenocarcinoma (PAAD) remains a lethal malignancy making the detection of novel prognostic biomarkers urgent. Limited studies have investigated the predictive capability of immune checkpoints in PAAD. METHOD: Gene expression data and correlative clinical information of PAAD cohort were obtained from public databases, including TCGA, ICGC, GTEX and GEO databases. Risk factors were screened and used to establish a risk score model through LASSO and Cox regression analyses. The prognostic ability of the risk score model was demonstrated. The association between risk score with immune cells infiltration, immune checkpoint genes expression, immunogenic cell death, somatic mutations and signaling pathways enrichment were analysed. scRNA-seq data were collected to confirmed the immune checkpoints expression in PAAD samples. The prognosis prediction ability of OX40/TNFRSF4 was identified. The mRNA and protein expression of OX40 in our clinical specimens were examined by RT-PCR and IHC method and its prognosis ability was verified. RESULTS: First of all, the difference of immune microenvironment between pancreatic cancer and adjacent tissues was shown. A risk score system based on three immune checkpoints (OX40, TNFSF14 and KIR3DL1) was established. The risk score model was an independent prognostic factor and performed well regarding overall survival (OS) predictions among PAAD patients. A nomogram was established to facilitate the risk model application in clinical prognosis. Immune cells including naive B cells, CD8+ T cells and Tregs were negatively correlated with the risk score. The risk score was associated with expression of immune checkpoint genes, immunogenic cell death related genes and somatic mutations. Glycolysis processes, IL-2-STAT5, IL-6-STAT3, and mTORC1 signaling pathways were enriched in the high-risk score group. Furthermore, scRNA-seq data confirmed that TNFRSF4, TNFSF14 and KIR3DL1 were expressed on immune cells in PAAD samples. We then identified OX40 as an independent prognosis-related gene, and a higher OX40 expression was associated with increased survival rate and immune environment change. In 84 PAAD clinical specimens collected from our center, we confirmed that higher OX40 mRNA expression levels were related to a good prognosis. The protein expression of OX40 on tumor-infiltrating immune cells (TIICs), endothelial cells and tumor cells was verified in PAAD tissues by immunohistochemistry (IHC) method. CONCLUSIONS: Overall, our findings strongly suggested that the three-immune checkpoints score system might be useful in the prognosis and design of personalized treatments for PAAD patients. Finally, we identified OX40 as an independent potential biomarker for PAAD prognosis prediction.


Subject(s)
Adenocarcinoma , Pancreatic Neoplasms , Humans , Prognosis , Adenocarcinoma/genetics , Pancreatic Neoplasms/genetics , CD8-Positive T-Lymphocytes , Endothelial Cells , Gene Expression Regulation, Neoplastic , Tumor Microenvironment , Pancreatic Neoplasms
20.
BMC Infect Dis ; 23(1): 231, 2023 Apr 14.
Article in English | MEDLINE | ID: mdl-37059987

ABSTRACT

BACKGROUND: Community-acquired pneumonia (CAP) is a major public health challenge worldwide. However, the aetiological and disease severity-related pathogens associated with CAP in adults in China are not well established based on the detection of both viral and bacterial agents. METHODS: A multicentre, prospective study was conducted involving 10 hospitals located in nine geographical regions in China from 2014 to 2019. Sputum or bronchoalveolar lavage fluid (BALF) samples were collected from each recruited CAP patient. Multiplex real-time PCR and bacteria culture methods were used to detect respiratory pathogens. The association between detected pathogens and CAP severity was evaluated. RESULTS: Among the 3,403 recruited eligible patients, 462 (13.58%) had severe CAP, and the in-hospital mortality rate was 1.94% (66/3,403). At least one pathogen was detected in 2,054 (60.36%) patients, with two or more pathogens were co-detected in 725 patients. The ten major pathogens detected were Mycoplasma pneumoniae (11.05%), Haemophilus influenzae (10.67%), Klebsiella pneumoniae (10.43%), influenza A virus (9.49%), human rhinovirus (9.02%), Streptococcus pneumoniae (7.43%), Staphylococcus aureus (4.50%), adenovirus (2.94%), respiratory syncytial viruses (2.35%), and Legionella pneumophila (1.03%), which accounted for 76.06-92.52% of all positive detection results across sampling sites. Klebsiella pneumoniae (p < 0.001) and influenza viruses (p = 0.005) were more frequently detected in older patients, whereas Mycoplasma pneumoniae was more frequently detected in younger patients (p < 0.001). Infections with Klebsiella pneumoniae, Staphylococcus aureus, influenza viruses and respiratory syncytial viruses were risk factors for severe CAP. CONCLUSIONS: The major respiratory pathogens causing CAP in adults in China were different from those in USA and European countries, which were consistent across different geographical regions over study years. Given the detection rate of pathogens and their association with severe CAP, we propose to include the ten major pathogens as priorities for clinical pathogen screening in China.


Subject(s)
Community-Acquired Infections , Legionella pneumophila , Pneumonia, Bacterial , Pneumonia , Humans , Adult , Aged , Pneumonia, Bacterial/diagnosis , Pneumonia, Bacterial/epidemiology , Pneumonia, Bacterial/complications , Prospective Studies , Pneumonia/diagnosis , Pneumonia/epidemiology , Pneumonia/etiology , Streptococcus pneumoniae , Mycoplasma pneumoniae , Respiratory Syncytial Viruses , Klebsiella pneumoniae , Community-Acquired Infections/diagnosis , Community-Acquired Infections/epidemiology , Community-Acquired Infections/etiology
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