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1.
China CDC Wkly ; 6(26): 619-623, 2024 Jun 28.
Article in English | MEDLINE | ID: mdl-38966310

ABSTRACT

What is already known about this topic?: Since May 2022, a global outbreak of mpox has emerged in more than 100 non-endemic countries. As of December 2023, over 90,000 cases had been reported. The outbreak has predominantly affected men who have sex with men (MSM), with sexual contact identified as the principal mode of transmission. What is added by this report?: Since June 2023, China has faced an occurrence of mpox, predominantly affecting the MSM population. Approximately 90% of those affected reported engaging in homosexual behavior within 21 days prior to symptom onset, a trend that aligns with the global outbreak pattern. The prompt identification of cases, diligent tracing of close contacts, and the implementation of appropriate management strategies have successfully mitigated the spread of mpox virus in China. What are the implications for public health practice?: We propose that mpox is transmitted locally within China. Drawing from our experiences in controlling the virus spread, it is crucial to investigate and formulate effective surveillance and educational strategies. Importantly, we must encourage high-risk populations to promptly seek medical care upon the onset of symptoms.

2.
mSystems ; : e0043024, 2024 07 02.
Article in English | MEDLINE | ID: mdl-38953319

ABSTRACT

The erythromycin resistance RNA methyltransferase (erm) confers cross-resistance to all therapeutically important macrolides, lincosamides, and streptogramins (MLS phenotype). The expression of erm is often induced by the macrolide-mediated ribosome stalling in the upstream co-transcribed leader sequence, thereby triggering a conformational switch of the intergenic RNA hairpins to allow the translational initiation of erm. We investigated the evolutionary emergence of the upstream erm regulatory elements and the impact of allelic variation on erm expression and the MLS phenotype. Through systematic profiling of the upstream regulatory sequences across all known erm operons, we observed that specific erm subfamilies, such as ermB and ermC, have independently evolved distinct configurations of small upstream ORFs and palindromic repeats. A population-wide genomic analysis of the upstream ermB regions revealed substantial non-random allelic variation at numerous positions. Utilizing machine learning-based classification coupled with RNA structure modeling, we found that many alleles cooperatively influence the stability of alternative RNA hairpin structures formed by the palindromic repeats, which, in turn, affects the inducibility of ermB expression and MLS phenotypes. Subsequent experimental validation of 11 randomly selected variants demonstrated an impressive 91% accuracy in predicting MLS phenotypes. Furthermore, we uncovered a mixed distribution of MLS-sensitive and MLS-resistant ermB loci within the evolutionary tree, indicating repeated and independent evolution of MLS resistance. Taken together, this study not only elucidates the evolutionary processes driving the emergence and development of MLS resistance but also highlights the potential of using non-coding genomic allele data to predict antibiotic resistance phenotypes. IMPORTANCE: Antibiotic resistance (AR) poses a global health threat as the efficacy of available antibiotics has rapidly eroded due to the widespread transmission of AR genes. Using Erm-dependent MLS resistance as a model, this study highlights the significance of non-coding genomic allelic variations. Through a comprehensive analysis of upstream regulatory elements within the erm family, we elucidated the evolutionary emergence and development of AR mechanisms. Leveraging population-wide machine learning (ML)-based genomic analysis, we transformed substantial non-random allelic variations into discernible clusters of elements, enabling precise prediction of MLS phenotypes from non-coding regions. These findings offer deeper insight into AR evolution and demonstrate the potential of harnessing non-coding genomic allele data for accurately predicting AR phenotypes.

3.
Article in English | MEDLINE | ID: mdl-38970800

ABSTRACT

The multiattribute method (MAM) has emerged as a powerful tool for simultaneously screening multiple product quality attributes of therapeutic antibodies. One such potential critical quality attribute (CQA) is glycation, a common modification that can impact the heterogeneity, functional activity, and immunogenicity of therapeutic antibodies. However, current methods for monitoring glycation levels in MAM are rare and not sufficiently rapid and accurate. In this study, an improved mass spectrometry (MS)-based MAM was developed to simultaneously monitor glycation and other quality attributes including afucosylation. The method was evaluated using two therapeutic antibodies with different glycosylation site numbers. Treatment with IdeS, Endo F2, and dithiothreitol generated three distinct subunits, and the glycation results obtained were similar to those treated with PNGase F, which is routinely used to release glycans; the sample processing time was greatly reduced while providing additional quality attribute information. The MS-based MAM was also employed to assess the glycation progression following forced glycation in various buffer solutions. A significant increase in oxidation was observed when forced glycation was conducted in an ammonium bicarbonate buffer solution, and a total of 23 potential glycation sites and 4 significantly oxidized sites were identified. Notably, we found that ammonium bicarbonate was found to specifically stimulate oxidation, while glycation had a synergistic effect on oxidation. These findings establish this study as a novel methodology for achieving a technologically advanced platform and concept that enhances the efficacy of product development and quality control, characterized by its broad-spectrum, rapid, and accurate nature.

6.
Adv Sci (Weinh) ; : e2401990, 2024 Jun 13.
Article in English | MEDLINE | ID: mdl-38868931

ABSTRACT

Photocatalytic CO2 reduction is considered as a promising strategy for CO2 utilization and producing renewable energy, however, it remains challenge in the improvement of photocatalytic performance for wide-band-gap photocatalyst with controllable product selectivity. Herein, the sulfur-doped In(OH)3 (In(OH)xSy-z) nanocubes are developed for selective photocatalytic reduction of CO2 to CH4 under simulated light irradiation. The CH4 yield of the optimal In(OH)xSy-1.0 can be enhanced up to 39 times and the CH4 selectivity can be regulated as high as 80.75% compared to that of pristine In(OH)3. The substitution of sulfur atoms for hydroxyl groups in In(OH)3 enhances the visible light absorption capability, and further improves the hydrophilicity behavior, which promotes the H2O dissociation into protons (H*) and accelerates the dynamic proton-feeding CO2 hydrogenation. In situ DRIFTs and DFT calculation confirm that the non-metal sulfur sites significantly weaken the over-potential of the H2O oxidation and prevent the formation of ·OH radicals, enabling the stabilization of *CHO intermediates and thus facilitating CH4 production. This work highlights the promotion effect of the non-metal doping engineering on wide-band-gap photocatalysts for tailoring the product selectivity in photocatalytic CO2 reduction.

7.
PLoS One ; 19(6): e0305932, 2024.
Article in English | MEDLINE | ID: mdl-38924047

ABSTRACT

Spatial interaction models with spatial origin-destination (OD) filters are powerful tools to characterize trip flows in space, which is a classic and important problem in regional science. To the authors' knowledge, existing studies adopting OD filters mostly specify the spatial dependence as an autoregressive process, which may not be the full picture of spatial effects. To examine the problem, this paper proposes the hypotheses that 1) spatial OD dependences can take place in both the spatial autoregressive term and the spatial error term in a spatial interaction model. 2) Estimating a spatial autoregressive model with spatial autoregressive disturbances (SARAR) model with OD filters would disentangle where the spatial dependence exists and by how much. 3) The marginal effects obtained from SARAR models would be preferred to analysts when SARAR models outperform spatial autoregressive (SAR) models and spatial error models (SEM) from the statistical point of view. To assess these hypotheses, this paper specifies, estimates, and applies SARAR models with OD filters to investigate trip distributions. By comparing against alternative models, this paper investigates the estimation results in SAR, SEM and SARAR models using an empirical data collected from Hangzhou, China. The contribution of this paper is to be the first in developing an SARAR model with OD filters for trip distribution analyses and examining its performance.


Subject(s)
Models, Statistical , China , Spatial Regression , Humans
8.
Molecules ; 29(12)2024 Jun 14.
Article in English | MEDLINE | ID: mdl-38930907

ABSTRACT

This study presents a quantum chemical investigation into the structural analysis and calculated Raman spectra of modeled amylose with varying units of linked glucose molecules. We systematically examined the rotation of hydroxymethyl groups and intramolecular hydrogen bonds within these amylose models. Our study found that as the number of linked glucose units increases, the linear structure becomes more complex, resulting in curled, cyclic, or helical structures facilitated by establishing various intramolecular interactions. The hydroxymethyl groups were confirmed to form interactions with oxygen atoms and with hydroxymethyl and hydroxyl groups from adjacent rings in the molecular structures. We identified distinct peaks and selected specific bands applicable in various analytical contexts by comparing their calculated Raman spectra. Representative vibrational modes within selected regions were identified across the different lengths of amylose models, serving as characteristic signatures for linear and more coiled structural conformations. Our findings contribute to a deeper understanding of amylose structures and spectroscopic signatures, with implications for theoretical studies and potential applications. This work provides valuable reference points for the detailed assignment of Raman peaks of amylose structure, facilitating their application in broader research on carbohydrate structures and their associated spectroscopic properties.


Subject(s)
Amylose , Glucose , Hydrogen Bonding , Spectrum Analysis, Raman , Amylose/chemistry , Glucose/chemistry , Quantum Theory , Models, Molecular , Molecular Structure
9.
J Pharm Biomed Anal ; 245: 116185, 2024 Aug 01.
Article in English | MEDLINE | ID: mdl-38723556

ABSTRACT

Human epidermal growth factor receptor 2 (HER2) is a key player in the pathogenesis and progression of breast cancer and is currently a primary target for breast cancer immunotherapy. Bioactivity determination is necessary to guarantee the safety and efficacy of therapeutic antibodies targeting HER2. Nevertheless, currently available bioassays for measuring the bioactivity of anti-HER2 mAbs are either not representative or have high variability. Here, we established a reliable reporter gene assay (RGA) based on T47D-SRE-Luc cell line that expresses endogenous HER2 and luciferase controlled by serum response element (SRE) to measure the bioactivity of anti-HER2 antibodies. Neuregulin-1 (NRG-1) can lead to the heterodimerization of HER2 on the cell membrane and induce the expression of downstream SRE-controlled luciferase, while pertuzumab can dose-dependently reverse the reaction, resulting in a good dose-response curve reflecting the activity of the antibody. After optimizing the relevant assay parameters, the established RGA was fully validated based on ICH-Q2 (R1), which demonstrated that the method had excellent specificity, accuracy, precision, linearity, and stability. In summary, this robust and innovative bioactivity determination assay can be applied in the development and screening, release control, biosimilar assessment and stability studies of anti-HER2 mAbs.


Subject(s)
Antibodies, Monoclonal, Humanized , Biological Assay , Genes, Reporter , Luciferases , Neuregulin-1 , Receptor, ErbB-2 , Receptor, ErbB-2/genetics , Receptor, ErbB-2/immunology , Receptor, ErbB-2/antagonists & inhibitors , Humans , Cell Line, Tumor , Antibodies, Monoclonal, Humanized/pharmacology , Biological Assay/methods , Luciferases/genetics , Neuregulin-1/genetics , Breast Neoplasms/drug therapy , Breast Neoplasms/immunology , Breast Neoplasms/genetics , Female , Antineoplastic Agents, Immunological/pharmacology , Reproducibility of Results , Response Elements
10.
Sci Data ; 11(1): 369, 2024 Apr 11.
Article in English | MEDLINE | ID: mdl-38605066

ABSTRACT

Theobroma cacao, the chocolate tree, is indigenous to the Amazon basin, the greatest biodiversity hotspot on earth. Recent advancement in plant genomics highlights the importance of de novo sequencing of multiple reference genomes to capture the genome diversity present in different cacao populations. In this study, three high-quality chromosome-level genomes of wild cacao were constructed, de novo assembled with HiFi long reads sequencing, and scaffolded using a reference-free strategy. These genomes represent the three most important genetic clusters of cacao trees from the Upper Amazon region. The three wild cacao genomes were compared with two reference genomes of domesticated cacao. The five cacao genetic clusters were inferred to have diverged in the early and middle Pleistocene period, approximately 1.83-0.69 million years ago. The results shown here serve as an example of understanding how the Amazonian biodiversity was developed. The three wild cacao genomes provide valuable resources for studying genetic diversity and advancing genetic improvement of this species.


Subject(s)
Cacao , Genome, Plant , Cacao/genetics
11.
MedComm (2020) ; 5(4): e543, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38585233

ABSTRACT

High metastatic propensity of osteosarcoma leads to its therapeutic failure and poor prognosis. Although nuclear activation miRNAs (NamiRNAs) are reported to activate gene transcription via targeting enhancer and further promote tumor metastasis, it remains uncertain whether NamiRNAs regulate osteosarcoma metastasis and their exact mechanism. Here, we found that extracellular vesicles of the malignant osteosarcoma cells (143B) remarkably increased the migratory abilities of MNNG cells representing the benign osteosarcoma cells by two folds, which attributed to their high miR-1246 levels. Specially, miR-1246 located in nucleus could activate the migration gene expression (such as MMP1) to accelerate MNNG cell migration through elevating the enhancer activities via increasing H3K27ac enrichment. Instead, MMP1 expression was dramatically inhibited after Argonaute 2 (AGO2) knockdown. Notably, in vitro assays demonstrated that AGO2 recognized the hybrids of miR-1246 and its enhancer DNA via PAZ domains to prevent their degradation from RNase H and these protective roles of AGO2 may favor the gene activation by miR-1246 in vivo. Collectively, our findings suggest that miR-1246 could facilitate osteosarcoma metastasis through interacting with enhancer to activate gene expression dependent on AGO2, highlighting the nuclear AGO2 as a guardian for NamiRNA-targeted gene activation and the potential of miR-1246 for osteosarcoma metastasis therapy.

12.
Front Bioeng Biotechnol ; 12: 1352098, 2024.
Article in English | MEDLINE | ID: mdl-38585708

ABSTRACT

The Chinese hamster ovarian (CHO) cells serve as a common choice in biopharmaceutical production, traditionally cultivated in stirred tank bioreactors (STRs). Nevertheless, the pursuit of improved protein quality and production output for commercial purposes demand exploration into new bioreactor types. In this context, inverted frustoconical shaking bioreactors (IFSB) present unique physical properties distinct from STRs. This study aims to compare the production processes of an antibody-based biotherapeutic in both bioreactor types, to enhance production flexibility. The findings indicate that, when compared to STRs, IFSB demonstrates the capability to produce an antibody-based biotherapeutic with either comparable or enhanced bioprocess performance and product quality. IFSB reduces shear damage to cells, enhances viable cell density (VCD), and improves cell state at a 5-L scale. Consequently, this leads to increased protein expression (3.70 g/L vs 2.56 g/L) and improved protein quality, as evidenced by a reduction in acidic variants from 27.0% to 21.5%. Scaling up the culture utilizing the Froude constant and superficial gas velocity ensures stable operation, effective mixing, and gas transfer. The IFSB maintains a high VCD and cell viability at both 50-L and 500-L scales. Product expression levels range from 3.0 to 3.6 g/L, accompanied by an improved acidic variants attribute of 20.6%-22.7%. The IFSB exhibits superior productivity and product quality, underscoring its potential for incorporation into the manufacturing process for antibody-based biotherapeutics. These results establish the foundation for IFSB to become a viable option in producing antibody-based biotherapeutics for clinical and manufacturing applications.

13.
Chem Biodivers ; : e202400277, 2024 Apr 30.
Article in English | MEDLINE | ID: mdl-38686912

ABSTRACT

The classical Chinese Medicine prescription, Quanzhenyiqitang (QZYQT), containing seven tonic herbs (Shudi, Dangshen, Maidong, Baizhu, Niuxi, Fuzi, and Wuweizi) is clinically used to treat chronic obstructive pulmonary disease (COPD). Although there are studies on the pharmacological effects of QZYQT, little attention has been paid to its active carbohydrate ingredients. We performed a systematic chemical analysis of the crude glycan isolates from the seven-herb decoction (GI-QZYQT) after confirming its anti-COPD activity. GI-QZYQT could enhance lung function, reduce lung damage, and alleviate inflammatory response in mice with COPD. Moreover, two monosaccharides (fructose and glucose) and six oligosaccharides (sucrose, melibiose, 1-kestose, raffinose, mannotriose, and stachyose), accounting for 40.23 % of GI-QZYQT, were discovered using hydrophilic interaction liquid chromatography-evaporative light-scattering detection. Inulin-type fructan with an average molecular weight of 2112 Da was identified using high-performance gel-permeation chromatography in combination with monosaccharide mapping analysis, accounting for 20.10 % of GI-QZYQT in mass. The comparison study showed that the identified monosaccharides, oligosaccharides, and the inulin-type fructan of GI-QZYQT were mainly derived from herbs of Shudi, Dangshen, Maidong, Baizhu, and Niuxi. These findings provide crucial information on the chemical composition of GI-QZYQT, which is vital for the in-depth understanding of its bioactivity, mechanism, and product development.

14.
Nature ; 629(8010): 165-173, 2024 May.
Article in English | MEDLINE | ID: mdl-38632398

ABSTRACT

Streptomyces are a genus of ubiquitous soil bacteria from which the majority of clinically utilized antibiotics derive1. The production of these antibacterial molecules reflects the relentless competition Streptomyces engage in with other bacteria, including other Streptomyces species1,2. Here we show that in addition to small-molecule antibiotics, Streptomyces produce and secrete antibacterial protein complexes that feature a large, degenerate repeat-containing polymorphic toxin protein. A cryo-electron microscopy structure of these particles reveals an extended stalk topped by a ringed crown comprising the toxin repeats scaffolding five lectin-tipped spokes, which led us to name them umbrella particles. Streptomyces coelicolor encodes three umbrella particles with distinct toxin and lectin composition. Notably, supernatant containing these toxins specifically and potently inhibits the growth of select Streptomyces species from among a diverse collection of bacteria screened. For one target, Streptomyces griseus, inhibition relies on a single toxin and that intoxication manifests as rapid cessation of vegetative hyphal growth. Our data show that Streptomyces umbrella particles mediate competition among vegetative mycelia of related species, a function distinct from small-molecule antibiotics, which are produced at the onset of reproductive growth and act broadly3,4. Sequence analyses suggest that this role of umbrella particles extends beyond Streptomyces, as we identified umbrella loci in nearly 1,000 species across Actinobacteria.


Subject(s)
Antibiosis , Bacterial Proteins , Bacterial Toxins , Streptomyces , Anti-Bacterial Agents/biosynthesis , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/metabolism , Anti-Bacterial Agents/pharmacology , Antibiosis/drug effects , Bacterial Proteins/chemistry , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Bacterial Proteins/pharmacology , Bacterial Proteins/ultrastructure , Bacterial Toxins/chemistry , Bacterial Toxins/genetics , Bacterial Toxins/metabolism , Bacterial Toxins/pharmacology , Cryoelectron Microscopy , Lectins/chemistry , Lectins/genetics , Lectins/metabolism , Lectins/ultrastructure , Microbial Sensitivity Tests , Models, Molecular , Streptomyces/chemistry , Streptomyces/drug effects , Streptomyces/genetics , Streptomyces/growth & development , Streptomyces coelicolor/chemistry , Streptomyces coelicolor/genetics , Streptomyces coelicolor/metabolism , Streptomyces griseus/drug effects , Streptomyces griseus/genetics , Streptomyces griseus/growth & development , Streptomyces griseus/metabolism
15.
Plant Cell Rep ; 43(5): 128, 2024 Apr 23.
Article in English | MEDLINE | ID: mdl-38652306

ABSTRACT

KEY MESSAGE: GWAS identified six loci at 25 kb downstream of WAK2, a crucial gene for cell wall and callus formation, enabling development of a SNP marker for enhanced callus induction potential. Efficient callus induction is vital for successful oil palm tissue culture, yet identifying genomic loci and markers for early detection of genotypes with high potential of callus induction remains unclear. In this study, immature male inflorescences from 198 oil palm accessions (dura, tenera and pisifera) were used as explants for tissue culture. Callus induction rates were collected at one-, two- and three-months after inoculation (C1, C2 and C3) as phenotypes. Resequencing generated 11,475,258 high quality single nucleotide polymorphisms (SNPs) as genotypes. GWAS was then performed, and correlation analysis revealed a positive association of C1 with both C2 (R = 0.81) and C3 (R = 0.50), indicating that C1 could be used as the major phenotype for callus induction rate. Therefore, only significant SNPs (P ≤ 0.05) in C1 were identified to develop markers for screening individuals with high potential of callus induction. Among 21 significant SNPs in C1, LD block analysis revealed six SNPs on chromosome 12 (Chr12) potentially linked to callus formation. Subsequently, 13 SNP markers were identified from these loci and electrophoresis results showed that marker C-12 at locus Chr12_12704856 can be used effectively to distinguish the GG allele, which showed the highest probability (69%) of callus induction. Furthermore, a rapid SNP variant detection method without electrophoresis was established via qPCR-based melting curve analysis. Our findings facilitated marker-assisted selection for specific palms with high potential of callus induction using immature male inflorescence as explant, aiding ortet palm selection in oil palm tissue culture.


Subject(s)
Arecaceae , Genome-Wide Association Study , Polymorphism, Single Nucleotide , Polymorphism, Single Nucleotide/genetics , Arecaceae/genetics , Tissue Culture Techniques/methods , Phenotype , Genotype , Genetic Loci/genetics , Linkage Disequilibrium/genetics , Quantitative Trait Loci/genetics
16.
J Pharm Pharmacol ; 2024 Apr 26.
Article in English | MEDLINE | ID: mdl-38666699

ABSTRACT

OBJECTIVE: Quanzhen Yiqi decoction (QZYQ) is a traditional Chinese medicine for treating chronic obstructive pulmonary disease. METHODS: Mice were exposed to cigarette smoke (CS) 6 days/week (40 cigarettes/day) for 24 weeks and then intragastrically administered QZYQ (4.72, 9.45, or 18.89 g/kg) or dexamethasone (DEX, 0.6 mg/kg) for 6 weeks. We examined the lung function and collected bronchoalveolar lavage fluid for inflammatory cell and cytokine quantification. The pathological lung changes, ROS and oxidative biomarkers were measured. We used immunohistochemistry and western blotting to evaluate the levels of Nrf2/HO-1, NLRP3/ASC/Caspase1/IL-1ß/IL-18. RESULTS: The CS group showed significant increases in the forced vital capacity, lung resistance, and chord compliance and a lower FEV50/FVC compared with the control, and QZYQ improved these changes. In addition, QZYQ effectively reduced emphysema, immune cell infiltration, and airway remodeling. QZYQ stimulated HO-1 expression and reduced oxidative stress through the Nrf2 pathway. QZYQ inhibited the production of NLRP3/ASC/Caspase-1 to inhibit IL-1ß and IL-18. CONCLUSION: Our study suggested that QZYQ can improve the function and histology of the lungs and reduce inflammatory cell recruitment. QZYQ inhibits ROS production and NLRP3 inflammasome activation by upregulating Nrf2 to reduce lung injury. The anti-inflammatory effects of QZYQ are similar to those of DEX.

17.
PLoS One ; 19(4): e0299493, 2024.
Article in English | MEDLINE | ID: mdl-38625928

ABSTRACT

Though facing significant challenges, coffee (Coffea arabica) grown in Haitian agroforestry systems are important contributors to rural livelihoods and provide several ecosystem services. However, little is known about their genetic diversity and the variety mixtures used. In light of this, there is a need to characterize Haitian coffee diversity to help inform revitalization of this sector. We sampled 28 diverse farms in historically important coffee growing regions of northern and southern Haiti. We performed KASP-genotyping of SNP markers and HiPlex multiplex amplicon sequencing for haplotype calling on our samples, as well as several Ethiopian and commercial accessions from international collections. This allowed us to assign Haitian samples to varietal groups. Our analyses revealed considerable genetic diversity in Haitian farms, higher in fact than many farmers realized. Notably, genetic structure analyses revealed the presence of clusters related to Typica, Bourbon, and Catimor groups, another group that was not represented in our reference accession panel, and several admixed individuals. Across the study areas, we found both mixed-variety farms and monovarietal farms with the historical and traditional Typica variety. This study is, to our knowledge, the first to genetically characterize Haitian C. arabica variety mixtures, and report the limited cultivation of C. canephora (Robusta coffee) in the study area. Our results show that some coffee farms are repositories of historical, widely-abandoned varieties while others are generators of new diversity through genetic mixing.


Subject(s)
Coffea , Coffee , Humans , Haiti , Ecosystem , Coffea/genetics , Genetic Variation
18.
MedComm (2020) ; 5(4): e528, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38606362

ABSTRACT

Lipid metabolic reprogramming is closely related to tumor progression with the mechanism not fully elucidated. Here, we report the immune-regulated role of lanosterol synthase (LSS), an essential enzyme in cholesterol synthesis. Database analysis and clinical sample experiments suggest that LSS was lowly expressed in colon and breast cancer tissues, which indicates poor prognosis. The biological activity of tumor cell lines and tumor progression in NOD scid gamma (NSG) mice were not affected after LSS knockdown, whereas LSS deficiency obviously aggravated tumor burden in fully immunized mice. Flow cytometry analysis showed that LSS knockdown significantly promoted the formation of tumor immunosuppressive microenvironment, characterized by the increase in M2 macrophages and polymorphonuclear myeloid-derived suppressor cells (PMN-MDSCs), as well as the decrease in anti-tumoral T lymphocytes. With the inhibition of myeloid infiltration or loss function of T lymphocytes, the propulsive effect of LSS knockdown on tumor progression disappeared. Mechanistically, LSS knockdown increased programmed death ligand 1 (PDL1) protein stability by 2,3-oxidosqualene (OS) binding to PDL1 protein. Anti-PDL1 therapy abolished LSS deficiency-induced immunosuppressive microenvironment and cancer progression. In conclusion, our results show that LSS deficiency promotes tumor progression by establishing an OS-PDL1 axis-dependent immunosuppressive microenvironment, indicative of LSS or OS as a potential hallmark of response to immune checkpoint blockade.

19.
Adv Sci (Weinh) ; 11(21): e2308993, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38516757

ABSTRACT

Neural stem cells (NSCs) transplantation is an attractive and promising treatment strategy for spinal cord injury (SCI). Various pathological processes including the severe inflammatory cascade and difficulty in stable proliferation and differentiation of NSCs limit its application and translation. Here, a novel physico-chemical bifunctional neural stem cells delivery system containing magnetic nanoparticles (MNPs and methylprednisolone (MP) is designed to repair SCI, the former regulates NSCs differentiation through magnetic mechanical stimulation in the chronic phase, while the latter alleviates inflammatory response in the acute phase. The delivery system releases MP to promote microglial M2 polarization, inhibit M1 polarization, and reduce neuronal apoptosis. Meanwhile, NSCs tend to differentiate into functional neurons with magnetic mechanical stimulation generated by MNPs in the static magnetic field, which is related to the activation of the PI3K/AKT/mTOR pathway. SCI mice achieve better functional recovery after receiving NSCs transplantation via physico-chemical bifunctional delivery system, which has milder inflammation, higher number of M2 microglia, more functional neurons, and axonal regeneration. Together, this bifunctional NSCs delivery system combined physical mechanical stimulation and chemical drug therapy is demonstrated to be effective, which provides new treatment insights into clinical transformation of SCI repair.


Subject(s)
Disease Models, Animal , Magnetite Nanoparticles , Methylprednisolone , Neural Stem Cells , Spinal Cord Injuries , Animals , Spinal Cord Injuries/therapy , Methylprednisolone/pharmacology , Mice , Neural Stem Cells/transplantation , Neural Stem Cells/drug effects , Magnetite Nanoparticles/chemistry , Magnetite Nanoparticles/therapeutic use , Cell Differentiation/drug effects , Stem Cell Transplantation/methods
20.
Dig Dis Sci ; 69(4): 1274-1286, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38446308

ABSTRACT

BACKGROUND & AIMS: Kinesin family member 18A (KIF18A) is notable for its aberrant expression across various cancer types and its pivotal role is driving cancer progression. In this study, we aim to investigate the intricate molecular mechanisms underlying the impact of KIF18A on the progression of HCC. METHODS: Western blotting assays, a quantitative real-time PCR and immunohistochemical analyses were performed to quantitatively assess KIF18A expression in HCC tissues. We then performed genetic manipulations within HCC cells by silencing endogenous KIF18A using short hairpin RNA (shRNA) and introducing exogenous plasmids to overexpress KIF18A. We monitored cell progression, analyzed cell cycle and cell apoptosis and assessed cell migration and invasion both in vitro and in vivo. Moreover, we conducted RNA-sequencing to explore KIF18A-related signaling pathways utilizing Reactome and KEGG enrichment methods and validated these critical mediators in these pathways. RESULTS: Analysis of the TCGA-LIHC database revealed pronounced overexpression of KIF18A in HCC tissues, the finding was subsequently confirmed through the analysis of clinical samples obtained from HCC patients. Notably, silencing KIF18A in cells led to an obvious inhibition of cell proliferation, migration and invasion in vitro. Furthermore, in subcutaneous and orthotopic xenograft models, suppression of KIF18A sgnificantly redudce tumor weight and the number of lung metastatic nodules. Mechanistically, KIF18A appears to facilitate cell proliferation by upregulating MAD2 and CDK1/CyclinB1 expression levels, with the activation of SMAD2/3 signaling contributing to KIF18A-driven metastasis. CONCLUSION: Our study elucidates the molecular mechanism by which KIF18A mediates proliferation and metastasis in HCC cells, offering new insights into potential therapeutic targets.


Subject(s)
Carcinoma, Hepatocellular , Kinesins , Liver Neoplasms , Humans , Carcinoma, Hepatocellular/genetics , Cell Line, Tumor , Cell Movement , Cell Proliferation , Gene Expression Regulation, Neoplastic , Kinesins/genetics , Kinesins/metabolism , Liver Neoplasms/genetics , Liver Neoplasms/metabolism , Liver Neoplasms/pathology , RNA, Small Interfering
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