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1.
Nat Commun ; 15(1): 3149, 2024 Apr 11.
Article in English | MEDLINE | ID: mdl-38605037

ABSTRACT

Pancreatic ductal adenocarcinoma (PDAC) develops through step-wise genetic and molecular alterations including Kras mutation and inactivation of various apoptotic pathways. Here, we find that development of apoptotic resistance and metastasis of KrasG12D-driven PDAC in mice is accelerated by deleting Plk3, explaining the often-reduced Plk3 expression in human PDAC. Importantly, a 41-kDa Plk3 (p41Plk3) that contains the entire kinase domain at the N-terminus (1-353 aa) is activated by scission of the precursor p72Plk3 at Arg354 by metalloendopeptidase nardilysin (NRDC), and the resulting p32Plk3 C-terminal Polo-box domain (PBD) is removed by proteasome degradation, preventing the inhibition of p41Plk3 by PBD. We find that p41Plk3 is the activated form of Plk3 that regulates a feed-forward mechanism to promote apoptosis and suppress PDAC and metastasis. p41Plk3 phosphorylates c-Fos on Thr164, which in turn induces expression of Plk3 and pro-apoptotic genes. These findings uncover an NRDC-regulated post-translational mechanism that activates Plk3, establishing a prototypic regulation by scission mechanism.


Subject(s)
Carcinoma, Pancreatic Ductal , Pancreatic Neoplasms , Humans , Mice , Animals , Proto-Oncogene Proteins p21(ras)/genetics , Proto-Oncogene Proteins p21(ras)/metabolism , Pancreatic Neoplasms/pathology , Carcinoma, Pancreatic Ductal/pathology , Metalloendopeptidases/genetics , Metalloendopeptidases/metabolism
2.
ACS Nano ; 18(14): 9958-9968, 2024 Apr 09.
Article in English | MEDLINE | ID: mdl-38547522

ABSTRACT

Single-molecule fluorescence in situ hybridization (smFISH) represents a promising approach for the quantitative analysis of nucleic acid biomarkers in clinical tissue samples. However, low signal intensity and high background noise are complications that arise from diagnostic pathology when performed with smFISH-based RNA imaging in formalin-fixed paraffin-embedded (FFPE) tissue specimens. Moreover, the associated complex procedures can produce uncertain results and poor image quality. Herein, by combining the high specificity of split DNA probes with the high signal readout of ZnCdSe/ZnS quantum dot (QD) labeling, we introduce QD split-FISH, a high-brightness smFISH technology, to quantify the expression of mRNA in both cell lines and clinical FFPE tissue samples of breast cancer and lung squamous carcinoma. Owing to its high signal-to-noise ratio, QD split-FISH is a fast, inexpensive, and sensitive method for quantifying mRNA expression in FFPE tumor tissues, making it suitable for biomarker imaging and diagnostic pathology.


Subject(s)
Breast Neoplasms , Quantum Dots , Humans , Female , RNA/analysis , Paraffin Embedding , In Situ Hybridization, Fluorescence/methods , RNA, Messenger/genetics , Breast Neoplasms/diagnostic imaging , Breast Neoplasms/genetics , Breast Neoplasms/metabolism , Formaldehyde
3.
Adv Healthc Mater ; 13(10): e2304207, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38175149

ABSTRACT

Myocardial infarction (MI) results in cardiomyocyte necrosis and conductive system damage, leading to sudden cardiac death and heart failure. Studies have shown that conductive biomaterials can restore cardiac conduction, but cannot facilitate tissue regeneration. This study aims to add regenerative capabilities to the conductive biomaterial by incorporating human endometrial mesenchymal stem cell (hEMSC)-derived exosomes (hEMSC-Exo) into poly-pyrrole-chitosan (PPY-CHI), to yield an injectable hydrogel that can effectively treat MI. In vitro, PPY-CHI/hEMSC-Exo, compared to untreated controls, PPY-CHI, or hEMSC-Exo alone, alleviates H2O2-induced apoptosis and promotes tubule formation, while in vivo, PPY-CHI/hEMSC-Exo improves post-MI cardiac functioning, along with counteracting against ventricular remodeling and fibrosis. All these activities are facilitated via increased epidermal growth factor (EGF)/phosphoinositide 3-kinase (PI3K)/AKT signaling. Furthermore, the conductive properties of PPY-CHI/hEMSC-Exo are able to resynchronize cardiac electrical transmission to alleviate arrythmia. Overall, PPY-CHI/hEMSC-Exo synergistically combines the cardiac regenerative capabilities of hEMSC-Exo with the conductive properties of PPY-CHI to improve cardiac functioning, via promoting angiogenesis and inhibiting apoptosis, as well as resynchronizing electrical conduction, to ultimately enable more effective MI treatment. Therefore, incorporating exosomes into a conductive hydrogel provides dual benefits in terms of maintaining conductivity, along with facilitating long-term exosome release and sustained application of their beneficial effects.


Subject(s)
Chitosan , Exosomes , Mesenchymal Stem Cells , Myocardial Infarction , Humans , Polymers/metabolism , Hydrogels/pharmacology , Hydrogels/metabolism , Pyrroles , Exosomes/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Delayed-Action Preparations/pharmacology , Hydrogen Peroxide/metabolism , Myocardial Infarction/therapy , Biocompatible Materials/pharmacology , Biocompatible Materials/metabolism , Myocytes, Cardiac/metabolism
4.
ACS Infect Dis ; 10(2): 377-383, 2024 Feb 09.
Article in English | MEDLINE | ID: mdl-38252850

ABSTRACT

Shigellosis poses an ongoing global public health threat. The presence and length of the O-antigen in lipopolysaccharide play critical roles in Shigella pathogenesis. The plasmid-mediated opt gene encodes a phosphoethanolamine (PEtN) transferase that catalyzes the addition of PEtN to the O-antigen of Shigella flexneri serotype X and Y strains, converting them into serotype Xv and Yv strains, respectively. Since 2002, these modified strains have become prevalent in China. Here we demonstrate that PEtN-mediated O-antigen modification in S. flexneri increase the severity of corneal infection in guinea pigs without any adaptive cost. This heightened virulence is associated with epithelial cell adhesion and invasion, as well as an enhanced inflammatory response of macrophage. Notably, PEtN addition allow S. flexneri to attenuate the binding of complement C3 and better resist phagocytosis, potentially contributing to the retention of S. flexneri in the host environment.


Subject(s)
Ethanolamines , O Antigens , Shigella flexneri , Animals , Guinea Pigs , O Antigens/genetics , O Antigens/metabolism , Serotyping , Plasmids , Shigella flexneri/genetics , Shigella flexneri/metabolism
5.
Am J Cancer Res ; 13(4): 1240-1258, 2023.
Article in English | MEDLINE | ID: mdl-37168356

ABSTRACT

Pancreatic adenocarcinoma (PAAD) has a poor prognosis and is relatively unresponsive to immunotherapy. Gasdermin C (GSDMC) induces pyroptosis in cancer cells and inflammation in the tumor microenvironment. However, whether GSDMC expression in PAAD is associated with survival or response to immunotherapy remains unknown. GSDMC expression and the relationship between GSDMC and patient survival or immune infiltration in PAAD were examined using data in the The Cancer Genome Atlas (TCGA), Gene Expression Ominbus (GEO), Genotype-Tissue Expression (GTEx) and Cancer Cell Line Encyclopedia (CCLE) databases. The TCGA PAAD cohort could be divided into two distinct risk groups based on the expression of GSDMC-related genes (GRGs). The TIDE algorithm predicted that the low-risk group was more responsive to immune checkpoint blockade therapy than the high-risk group. A novel 15-gene signature was constructed and could predict the prognosis of PAAD. In addition, the 15-gene signature model predicted the infiltration of immune cells and Immune checkpoint blockade (ICB) treatment response. Immunohistochemical staining assessment of patient-derived human tissue microarray (TMA) from 139 cases of local PAAD patients revealed a positive correlation between GSDMC expression and PD-L1 expression but a negative correlation between GSDMC expression and infiltration of low CD8+ T cells. Moreover, the overexpression of GSDMC was related to poor overall survival (OS). This study suggests that GSDMC is a valuable biomarker for predicting PAAD prognosis and predicts the immunotherapy response of PAAD.

7.
J Oncol ; 2023: 1904309, 2023.
Article in English | MEDLINE | ID: mdl-36814558

ABSTRACT

Background: TP53 is a very common tumor suppressor gene and has implicated in various cancers. A systematic immunological analysis of TP53 somatic mutation classification in multiple cancers is still lacking. Methods: To assess the immunological value of TP53 somatic mutation classification in various cancers, we integrated a series of bioinformatics methods to analyze the role of TP53 gene across the public databases, such as UCSC Xena, Cancer Cell Line Encyclopedia (CCLE), Ensembl, and Genotype-Tissue Expression (GTEx). Results: The results revealed that the TP53 expression level had significant difference in tumor tissues and normal tissues, and it had a high expression level in most malignant tumors. Moreover, the missense mutation is the most common type of TP53 mutation in most cancers. In addition, the Cox proportional hazards model analysis and Kaplan-Meier (KM) survival analysis demonstrated that the TP53 expression is a high-risk factor in brain lower-grade glioma (LGG), prostate adenocarcinoma (PRAD), and uterine carcinosarcoma (UCS), which is opposite in uterine corpus endometrial carcinoma (UCEC). Besides, compared to the TP53 nontruncating mutation classification samples, we found that TP53 truncating mutation samples had lower TP53 expression levels in certain types of cancer. Notably, TP53 was associated with the mismatch repair (MMR) gene in some cancers which contained truncating or nontruncating mutation. Based on the classification of truncating or nontruncating mutation, we also discovered that TP53 expression was positively or negatively correlated with the immune score, stromal score, and the levels of immune cell infiltration in different cancers. Conclusions: Our research reveals an overarching landscape of immunological value on TP53 status in various malignant tumors. According to our results, we demonstrate that TP53 also plays an immunological role in various cancers.

8.
Mol Carcinog ; 62(5): 716-726, 2023 05.
Article in English | MEDLINE | ID: mdl-36807309

ABSTRACT

The therapeutic effects of existing drug regimens against pancreatic neuroendocrine neoplasms (pNENs) remain limited, and identifying ideal therapeutic targets is warranted. PDZ binding kinase (PBK) may play an oncogenic role in most solid tumors. However, its function in pNEN remains unclear. In this study, pNEN samples and International Cancer Genome Consortium data were used to determine the clinical significance of PBK. Cell counting and CCK8 assays were used to assess cell proliferation. Flow cytometry was used to assess drug-induced apoptosis and cell cycle arrest. An in vivo PBK-targeting experiment was performed in mice bearing pNENs. Western blotting, quantitative PCR, and immunohistochemistry were performed to assess the molecular mechanisms. PBK was significantly upregulated in pNEN tissues compared with paracancerous tissues. Additionally, PBK was a poor prognostic factor for pNEN patients. PBK was found to promote the proliferation of pNEN cells by activating the AKT/mTOR pathway. Furthermore, PBK inhibition combined with everolimus treatment had enhanced antitumour effects on pNEN via inhibiting AKT/mTOR pathway and inducing G0/G1 phase cell cycle arrest. This study highlights that PBK plays an oncogenic role in and is a promising therapeutic target for pNEN.


Subject(s)
Mitogen-Activated Protein Kinase Kinases , Neuroendocrine Tumors , Pancreatic Neoplasms , Animals , Mice , Cell Line, Tumor , Extracellular Signal-Regulated MAP Kinases , Mitogen-Activated Protein Kinase Kinases/metabolism , Neuroendocrine Tumors/drug therapy , Neuroendocrine Tumors/genetics , Neuroendocrine Tumors/metabolism , Pancreatic Neoplasms/drug therapy , Pancreatic Neoplasms/genetics , Pancreatic Neoplasms/metabolism , Proto-Oncogene Proteins c-akt/metabolism , TOR Serine-Threonine Kinases/genetics , TOR Serine-Threonine Kinases/metabolism
9.
Mol Cell Biochem ; 478(6): 1191-1204, 2023 Jun.
Article in English | MEDLINE | ID: mdl-36266491

ABSTRACT

Human endometrial mesenchymal stem cells (hEMSCs) have been shown to promote neo-vascularization; however, its angiogenic function lessens with age. To determine the optimal conditions for maximizing hEMSC angiogenic capacity, we examined the effects of serial passaging on hEMSC activity. hEMSCs were cultured from passages (P) 3, 6, 9, and 12, and analyzed for proliferation, migration, differentiation and senescence, as well as their capacity to induce angiogenesis. The results showed that hEMSC proliferation and migration significantly decreased after P12. Furthermore, hEMSC differentiation into adipogenic and osteogenic lineages, as well as their proangiogenic capacity, gradually decreased from P9-12, while senescence only occurred after P12. Evaluation of angiogenic-related protein levels showed that both transforming growth factor ß2 and Tie-2 was significantly reduced in hEMSCs at P12, compared to P3, possibly serving as the basis behind their lowered angiogenic capacity. Furthermore, in vivo angiogenesis evaluation with Matrigel plug assay showed that the optimal hEMSC to HUVEC ratio, for maximizing vessel formation, was 1:4. This study showed that hEMSC passaging was associated with lowered cellular functioning, bringing them closer to a senescent phenotype, especially after P12, thereby defining the optimal time period for cultivating fully functional hEMSCs for therapeutic applications.


Subject(s)
Cardiovascular Physiological Phenomena , Mesenchymal Stem Cells , Humans , Cell Differentiation , Neovascularization, Physiologic , Osteogenesis , Mesenchymal Stem Cells/metabolism , Cells, Cultured , Cell Proliferation
10.
Biochem Biophys Res Commun ; 627: 45-51, 2022 10 30.
Article in English | MEDLINE | ID: mdl-36007334

ABSTRACT

The benefits of autologous cell therapy for cardiac repair are diminished in aged individuals due to the limited quality and poor tolerance of aged stem cells in the ischemic micro-environment. The safe and efficient methods to improve the therapeutic effect of aged stem cells are needed to treat the increasing number of aged patients with cardiac diseases. In the present study, we aimed to determine whether hypoxic preconditioning can improve the therapeutic effect of aged stem cells even if the responsiveness of aged MSCs is poor, and to seek the underlying mechanism. Using a murine model of MI, our results showed that hypoxic preconditioning promoted the therapeutic effect of aged BMSCs, which was expressed in improved cardiac function, decreased scar size and alleviated cardiac remodeling in vivo. This in vivo effect of hypoxic preconditioned aged BMSCs was associated with alleviated inflammation, oxidative stress and apoptosis in infarcted heart. In vitro studies confirmed that hypoxic preconditioned aged BMSCs exert cytoprotective impacts on H9C2 cells against lethal hypoxia injury via attenuating oxidative stress and apoptosis. Our data support the promise of hypoxic preconditioning as a potential strategy to improve autologous stem cell therapy for ischemic heart injury in aged individuals.


Subject(s)
Mesenchymal Stem Cell Transplantation , Mesenchymal Stem Cells , Myocardial Infarction , Aged , Animals , Apoptosis , Humans , Hypoxia , Inflammation/therapy , Mesenchymal Stem Cell Transplantation/methods , Mice , Myocardial Infarction/therapy , Oxidative Stress
11.
Leukemia ; 36(8): 2064-2075, 2022 08.
Article in English | MEDLINE | ID: mdl-35697790

ABSTRACT

Extra-nodal NK/T-cell lymphoma, nasal type (ENKTCL) is a highly aggressive Epstein-Barr virus associated lymphoma, typically presenting in the nasal and paranasal areas. We assembled a large series of ENKTCL (n = 209) for comprehensive genomic analysis and correlative clinical study. The International Lymphoma Prognostic Index (IPI), site of disease, stage, lymphadenopathy, and hepatomegaly were associated with overall survival. Genetic analysis revealed frequent oncogenic activation of the JAK/STAT3 pathway and alterations in tumor suppressor genes (TSGs) and genes associated with epigenomic regulation. Integrated genomic analysis including recurrent mutations and genomic copy number alterations using consensus clustering identified seven distinct genetic clusters that were associated with different clinical outcomes, thus constituting previously unrecognized risk groups. The genetic profiles of ENTKCLs from Asian and Hispanic ethnic groups showed striking similarity, indicating shared pathogenetic mechanism and tumor evolution. Interestingly, we discovered a novel functional cooperation between activating STAT3 mutations and loss of the TSG, PRDM1, in promoting NK-cell growth and survival. This study provides a genetic roadmap for further analysis and facilitates investigation of actionable therapeutic opportunities in this aggressive lymphoma.


Subject(s)
Epstein-Barr Virus Infections , Lymphoma, Extranodal NK-T-Cell , Lymphoma, T-Cell, Peripheral , Epstein-Barr Virus Infections/complications , Epstein-Barr Virus Infections/genetics , Genetic Profile , Genomics , Herpesvirus 4, Human , Humans , Killer Cells, Natural/pathology , Lymphoma, Extranodal NK-T-Cell/pathology , Lymphoma, T-Cell, Peripheral/pathology
12.
J Pathol ; 257(5): 650-662, 2022 08.
Article in English | MEDLINE | ID: mdl-35451500

ABSTRACT

Tumor-infiltrating lymphocytes (TILs) offer a key for morphological diagnosis of lymphoepithelioma-like carcinoma (LELC) and are the foundation of oncoimmunology. To date, no reports have found a specific risk stratification value of TILs and related it to genomic variation in LELC. Based on the stromal TILs (str-TILs) ratio, we classified 105 Epstein-Barr virus (EBV)-associated LELC cases into two subtypes: patients with ≥60% str-TILs area ratio in tumor were classified as subtype I, and otherwise as subtype II. Subtype I patients had significantly better progression-free survival (PFS) and overall survival (OS). We also explored the genomic characteristics of EBV-associated LELC within different involved organs. We performed whole-exome sequencing for 51 patients with enough tissue and analyzed the genomic characteristics of EBV-associated LELC. Overall, EBV-associated LELCs were characterized by a low somatic mutation rate and copy number variations; the enriched genetic lesions affected RTK-RAS, PI3K, and cell cycle pathways. Moreover, EBV-associated LELCs from different organs were more similar to each other genetically as compared with other traditional carcinomas of the same sites-as evidenced by unsupervised clustering based on the quantitative data from both mutation signature and chromosomal aneuploidies. Notably, EBV-associated LELC patients with oncogenic driver alterations showed a worse prognosis compared with patients without such alterations. © 2022 The Pathological Society of Great Britain and Ireland.


Subject(s)
Carcinoma, Squamous Cell , Epstein-Barr Virus Infections , DNA Copy Number Variations , Epstein-Barr Virus Infections/complications , Epstein-Barr Virus Infections/genetics , Genomics , Herpesvirus 4, Human/genetics , Humans , Lymphocytes, Tumor-Infiltrating
13.
Mol Cancer ; 21(1): 70, 2022 03 10.
Article in English | MEDLINE | ID: mdl-35272681

ABSTRACT

BACKGROUND: Pancreatic cancer is one of the most lethal cancers worldwide. The IAPs function as E3 ubiquitin ligases and contribute to pancreatic cancer initiation, progression, and metastasis. Although IAP-targeted therapies have been developed and shown anticancer efficacy in preclinical settings, none of them has been approved yet. METHODS: Transcriptome data from public datasets were used to analyze the correlation of IAPs and E2s, and the biological function of E2 UbcH5c in pancreatic cancer. A structure-based virtual screen was used to identify UbcH5c inhibitor, and surface plasmon resonance analysis and cellular thermal shift assays were employed to evaluate the binding affinity. The anticancer activities were demonstrated through in vitro and in vivo assays, while the related mechanisms were explored through transcriptomic and proteomic analyses and confirmed by western blot, immunofluorescence, and qRT-PCR. RESULTS: UbcH5c is positively correlated with the expression of IAPs in pancreatic cancer. We further found that UbcH5c is overexpressed and associated with a poor prognosis in pancreatic cancer. We identified a small-molecule UbcH5c inhibitor, termed DHPO, which directly bound to UbcH5c protein. DHPO inhibited cell viability and colony formation, induced apoptosis, and suppressed migration and invasion of pancreatic cancer cells in vitro. The compound inhibited UbcH5c-mediated IκBα degradation and NF-κB activation, which is critical for its anticancer activity. Furthermore, DHPO suppressed the tumor growth and metastasis in two orthotopic pancreatic tumor mouse models. CONCLUSIONS: These results indicated that inhibiting UbcH5c is a novel and effective strategy for treating pancreatic cancer and DHPO represents a new class of UbcH5c inhibitor and may be further developed as an anti-pancreatic cancer therapeutic agent.


Subject(s)
Pancreatic Neoplasms , Ubiquitin-Conjugating Enzymes , Animals , Cell Line, Tumor , Humans , Mice , NF-kappa B/metabolism , Pancreatic Neoplasms/pathology , Proteomics , Ubiquitin-Conjugating Enzymes/metabolism , Ubiquitin-Protein Ligases/metabolism , Pancreatic Neoplasms
14.
ACS Appl Mater Interfaces ; 14(6): 8010-8024, 2022 Feb 16.
Article in English | MEDLINE | ID: mdl-35107272

ABSTRACT

Although proton exchange membrane fuel cells have received attention, the high costs associated with Pt-based catalysts in membrane electrode assemblies (MEAs) remain a huge obstacle for large-scale applications. To solve this urgent problem, the utilization efficiency of Pt in MEAs must be increased. Facing numerous interacting parameters in an attempt to keep experimental costs as low as possible, we innovatively introduce machine learning (ML) to achieve this goal. Nine different ML algorithms are trained on the experimental dataset from our laboratory to precisely predict the performance and Pt utilization (maximum R2 = 0.973/0.968). To determine the best synthesis conditions, black-box interpretation methods are applied to provide reliable insights from both qualitative and quantitative perspectives. The optimized choices of ionomer/catalyst ratio, water content, organic solvent, catalyst loading, stirring method, solid content, and ultrasonic spraying flow rate are properly made with few experimental attempts under ML results' guidance. Promising Pt utilization of 0.147 gPt kW-1 and a power density of 1.02 W cm-2 are achieved at 0.6 V in a single cell (H2/air) at an ultralow total loading of 0.15 mg Pt cm-2. Therefore, this work contributes to the economy of hydrogen energy by paving the way for MEA optimization with complex parameters by ML.

15.
Nat Commun ; 12(1): 7041, 2021 12 06.
Article in English | MEDLINE | ID: mdl-34873175

ABSTRACT

Despite unprecedented responses of some cancers to immune checkpoint blockade (ICB) therapies, the application of checkpoint inhibitors in pancreatic cancer has been unsuccessful. Glucocorticoids and glucocorticoid receptor (GR) signaling are long thought to suppress immunity by acting on immune cells. Here we demonstrate a previously undescribed tumor cell-intrinsic role for GR in activating PD-L1 expression and repressing the major histocompatibility complex class I (MHC-I) expression in pancreatic ductal adenocarcinoma (PDAC) cells through transcriptional regulation. In mouse models of PDAC, either tumor cell-specific depletion or pharmacologic inhibition of GR leads to PD-L1 downregulation and MHC-I upregulation in tumor cells, which in turn promotes the infiltration and activity of cytotoxic T cells, enhances anti-tumor immunity, and overcomes resistance to ICB therapy. In patients with PDAC, GR expression correlates with high PD-L1 expression, low MHC-I expression, and poor survival. Our results reveal GR signaling in cancer cells as a tumor-intrinsic mechanism of immunosuppression and suggest that therapeutic targeting of GR is a promising way to sensitize pancreatic cancer to immunotherapy.


Subject(s)
B7-H1 Antigen/immunology , Carcinoma, Pancreatic Ductal/immunology , Histocompatibility Antigens Class I/immunology , Pancreatic Neoplasms/immunology , Receptors, Glucocorticoid/immunology , Tumor Escape/immunology , Animals , B7-H1 Antigen/genetics , B7-H1 Antigen/metabolism , Carcinoma, Pancreatic Ductal/genetics , Carcinoma, Pancreatic Ductal/therapy , Cell Line, Tumor , Gene Expression Regulation, Neoplastic , Histocompatibility Antigens Class I/genetics , Histocompatibility Antigens Class I/metabolism , Humans , Immunoblotting , Immunotherapy/methods , Kaplan-Meier Estimate , Mice, Inbred C57BL , Pancreatic Neoplasms/genetics , Pancreatic Neoplasms/therapy , Receptors, Glucocorticoid/genetics , Receptors, Glucocorticoid/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Tumor Escape/genetics
16.
Antibiotics (Basel) ; 10(7)2021 Jul 19.
Article in English | MEDLINE | ID: mdl-34356793

ABSTRACT

Since the first report of the plasmid-mediated, colistin-resistant gene, mcr-1, nine mcr genes and their subvariants have been identified. The spreading scope of mcr-1~10 varies greatly, suggesting that mcr-1~10 may have different evolutionary advantages. Depending on MCR family phylogeny, mcr-6 is highly similar to mcr-1 and -2, and mcr-7~10 are highly similar to mcr-3 and -4. We compared the expression effects of MCR-1~5 on bacteria of common physiological background. The MCR-1-expressing strain showed better growth than did MCR-2~5-expressing strains in the presence of colistin. LIVE/DEAD staining analysis revealed that MCR-3~5 expression exerted more severe fitness burdens on bacteria than did MCR-1 and -2. Bacteria expressing MCRs except MCR-2 showed enhanced virulence with increased epithelial penetration ability determined by trans-well model (p < 0.05). Enhanced virulence was also observed in the Galleria mellonella model, which may have resulted from bacterial membrane damage and different levels of lipopolysaccharide (LPS) release due to MCR expression. Collectively, MCR-1-expressing strain showed the best survival advantage of MCR-1~5-expressing strains, which may partly explain the worldwide distribution of mcr-1. Our results suggested that MCR expression may cause increased bacterial virulence, which is alarming, and further attention will be needed to focus on the control of infectious diseases caused by mcr-carrying pathogens.

17.
Adv Sci (Weinh) ; 8(18): e2101336, 2021 09.
Article in English | MEDLINE | ID: mdl-34323389

ABSTRACT

Mobile colistin resistance enzyme MCR-3 is a phosphoethanolamine transferase modifying lipid A in Gram-negative bacteria. MCR-3 generally mediates low-level (≤8 mg L-1 ) colistin resistance among Enterobacteriaceae, but occasionally confers high-level (>128 mg L-1 ) resistance in aeromonads. Herein, it is determined that MCR-3, together with another lipid A modification mediated by the arnBCADTEF operon, may be responsible for high-level colistin resistance in aeromonads. Lipid A is the critical site of pathogens for Toll-like receptor 4 recognizing. However, it is unknown whether or how MCR-3-mediated lipid A modification affects the host immune response. Compared with the wild-type strains, increased mortality is observed in mice intraperitoneally-infected with mcr-3-positive Aeromonas salmonicida and Escherichia coli strains, along with sepsis symptoms. Further, mcr-3-positive strains show decreased clearance rates than wild-type strains, leading to bacterial accumulation in organs. The increased mortality is tightly associated with the increased tissue hypoxia, injury, and post-inflammation. MCR-3 expression also impairs phagocytosis efficiency both in vivo and in vitro, contributing to the increased persistence of mcr-3-positive bacteria in tissues compared with parental strains. This study, for the first time, reveals a dual function of MCR-3 in bacterial resistance and pathogenicity, which calls for caution in treating the infections caused by mcr-positive pathogens.


Subject(s)
Aeromonas salmonicida/drug effects , Anti-Bacterial Agents/pharmacology , Colistin/pharmacology , Drug Resistance, Bacterial/genetics , Escherichia coli/drug effects , Phagocytosis/genetics , Aeromonas salmonicida/genetics , Animals , Escherichia coli/genetics , Female , Genes, Bacterial/genetics , Mice , Mice, Inbred BALB C , Microbial Sensitivity Tests
18.
Stem Cell Res Ther ; 12(1): 344, 2021 06 10.
Article in English | MEDLINE | ID: mdl-34112245

ABSTRACT

BACKGROUND: The human endometrium in premenopausal women is an active site of physiological angiogenesis, with regenerative cells present, suggesting that the endometrium contains adult angiogenic stem cells. In the context of cardiac repair after ischemic injury, angiogenesis is a crucial process to rescue cardiomyocytes. We therefore investigated whether human endometrium-derived stem cells (hEMSCs) can be used for cardiac repair after ischemic injury and their possible underlying mechanisms. METHODS: Comparisons were made between hEMSCs successfully isolated from 22 premenopausal women and human bone marrow mesenchymal stem cells (hBMSCs) derived from 25 age-matched patients. Cell proliferation, migration, differentiation, and angiogenesis were evaluated through in vitro experiments, while the ability of hEMSCs to restore cardiac function was examined by in vivo cell transplantation into the infarcted nude rat hearts. RESULTS: In vitro data showed that hEMSCs had greater proliferative and migratory capacities, whereas hBMSCs had better adipogenic differentiation ability. Human umbilical cord vein endothelial cells, treated with conditioned medium from hEMSCs, had significantly higher tube formation than that from hBMSCs or control medium, indicating greater angiogenic potentials for hEMSCs. In vivo, hEMSC transplantation preserved cardiac function, decreased infarct size, and improved tissue repair post-injury. Cardiac metabolism, assessed by 18F-FDG uptake, showed that 18F-FDG uptake at the infarction area was significantly higher in both hBMSC and hEMSC groups, compared to the PBS control group, with hEMSCs having the highest uptake, suggesting hEMSC treatment improves cardiomyocyte metabolism and survival after injury. Mechanistic assessment of the angiogenic potential for hEMSCS revealed that angiogenesis-related factors angiopoietin 2, Fms-like tyrosine kinase 1, and FGF9 were significantly upregulated in hEMSC-implanted infarcted hearts, compared to the PBS control group. CONCLUSION: hEMSCs, compared to hBMSCs, have greater capacity to induce angiogenesis, and improved cardiac function after ischemic injury.


Subject(s)
Mesenchymal Stem Cell Transplantation , Myocardial Infarction , Cell Differentiation , Endometrium , Female , Humans , Myocardial Infarction/therapy , Myocytes, Cardiac , Neovascularization, Physiologic , Stem Cells
19.
Mol Cell Endocrinol ; 523: 111144, 2021 03 01.
Article in English | MEDLINE | ID: mdl-33383107

ABSTRACT

In this study, we aimed to clarify the role of PIM-1 in papillary thyroid carcinoma (PTC) in vitro and investigate the relationship between PIM-1 and redox proteins (NOX4, SOD2, and GPX2) at the tissue and cellular levels. As a PIM-1 inhibitor, SGI-1776 inhibited cell proliferation, colony formation, migration and induced an increase in apoptosis and reactive oxygen species in two PTC cell lines (BCPAP and TPC-1). The expressions of PIM-1, SOD2 and GPX2 were downregulated after siNOX4 exposure. Immunohistochemistry in 120 PTC patients showed that all four proteins exhibited higher expression levels in PTC tissues than in adjacent normal tissues. PIM-1 expression was related to NOX4, SOD2, and GPX2 expressions. The Cancer Genome Atlas database analysis showed the significant correlation between the expression of NOX4 and PIM-1. Our results demonstrated that PIM-1 played an important oncogenic role in PTC carcinogenesis that may be related to oxidative stress.


Subject(s)
Carcinogenesis/pathology , Disease Progression , Oncogenes , Oxidative Stress , Proto-Oncogene Proteins c-pim-1/metabolism , Thyroid Cancer, Papillary/genetics , Thyroid Neoplasms/genetics , Apoptosis/drug effects , Apoptosis/genetics , Carcinogenesis/drug effects , Carcinogenesis/genetics , Cell Line, Tumor , Cell Movement/drug effects , Cell Movement/genetics , Cell Proliferation/drug effects , Cell Proliferation/genetics , Databases, Genetic , Female , Gene Expression Regulation, Neoplastic/drug effects , Humans , Imidazoles/pharmacology , Male , Middle Aged , Neoplasm Proteins/genetics , Neoplasm Proteins/metabolism , Oxidative Stress/drug effects , Oxidative Stress/genetics , Proto-Oncogene Proteins c-pim-1/genetics , Pyridazines/pharmacology , Reactive Oxygen Species/metabolism , Thyroid Cancer, Papillary/pathology , Thyroid Neoplasms/pathology , Tumor Stem Cell Assay
20.
Angew Chem Int Ed Engl ; 59(43): 19175-19183, 2020 Oct 19.
Article in English | MEDLINE | ID: mdl-32662229

ABSTRACT

Traditionally, a larger number of experiments are needed to optimize the performance of the membrane electrode assembly (MEA) in proton-exchange membrane fuel cells (PEMFCs) since it involves complex electrochemical, thermodynamic, and hydrodynamic processes. Herein, we introduce artificial intelligence (AI)-aided models for the first time to determine key parameters for nonprecious metal electrocatalyst-based PEMFCs, thus avoiding unnecessary experiments during MEA development. Among 16 competing algorithms widely applied in the AI field, decision tree and XGBoost showed good accuracy (86.7 % and 91.4 %) in determining key factors for high-performance MEA. Artificial neural network (ANN) shows the best accuracy (R2=0.9621) in terms of predictions of the maximum power density and a decent reproducibility (R2>0.99) on uncharted I-V polarization curves with 26 input features. Hence, machine learning is shown to be an excellent method for improving the efficiency of MEA design and experiments.

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