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1.
J Nanobiotechnology ; 22(1): 540, 2024 Sep 05.
Article in English | MEDLINE | ID: mdl-39237942

ABSTRACT

To assess the efficacy of a novel 3D biomimetic hydrogel scaffold with immunomodulatory properties in promoting fracture healing. Immunomodulatory scaffolds were used in cell experiments, osteotomy mice treatment, and single-cell transcriptomic sequencing. In vitro, fluorescence tracing examined macrophage mitochondrial transfer and osteogenic differentiation of bone marrow-derived mesenchymal stem cells (BMSCs). Scaffold efficacy was assessed through alkaline phosphatase (ALP), Alizarin Red S (ARS) staining, and in vivo experiments. The scaffold demonstrated excellent biocompatibility and antioxidant-immune regulation. Single-cell sequencing revealed a shift in macrophage distribution towards the M2 phenotype. In vitro experiments showed that macrophage mitochondria promoted BMSCs' osteogenic differentiation. In vivo experiments confirmed accelerated fracture healing. The GAD/Ag-pIO scaffold enhances osteogenic differentiation and fracture healing through immunomodulation and promotion of macrophage mitochondrial transfer.


Subject(s)
Cell Differentiation , Hydrogels , Macrophages , Mesenchymal Stem Cells , Mitochondria , Osteogenesis , Tissue Scaffolds , Animals , Osteogenesis/drug effects , Mitochondria/metabolism , Mitochondria/drug effects , Macrophages/drug effects , Macrophages/metabolism , Macrophages/cytology , Hydrogels/chemistry , Hydrogels/pharmacology , Cell Differentiation/drug effects , Mesenchymal Stem Cells/cytology , Mesenchymal Stem Cells/drug effects , Mice , Tissue Scaffolds/chemistry , Male , Cells, Cultured , Mice, Inbred C57BL
2.
Cancer Sci ; 114(5): 1943-1957, 2023 May.
Article in English | MEDLINE | ID: mdl-36642785

ABSTRACT

Radioresistance remains a major obstacle to efficacious radiotherapy in non-small-cell lung cancer (NSCLC). DNA replication proteins are novel targets for radiosensitizers. POLQ is a DNA polymerase involved in DNA damage response and repair. We found that POLQ is overexpressed in NSCLC and is clinically correlated with high tumor stage, poor prognosis, increased tumor mutational burden, and ALK and TP5 mutation status; POLQ inhibition impaired lung tumorigenesis. Notably, POLQ expression was higher in radioresistant lung cancer cells than in wild-type cancer cells. Moreover, POLQ expression was further increased in radioresistant cells after radiation. Enhanced radioresistance is through a prolonged G2/M phase and faster repair of DNA damage, leading to reduced radiation-induced apoptosis. Novobiocin (NVB), a POLQ inhibitor, specifically targeted cancer cells. Genetic knockdown of POLQ or pharmacological inhibition by NVB decreased radioresistance in lung adenocarcinoma while causing little toxicity to normal pulmonary epithelial cells. In conclusion, POLQ is a promising and practical cancer-specific target to impair tumorigenesis and enhance radiosensitivity in NSCLC.


Subject(s)
Adenocarcinoma of Lung , Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Humans , Carcinoma, Non-Small-Cell Lung/genetics , Carcinoma, Non-Small-Cell Lung/radiotherapy , Lung Neoplasms/genetics , Lung Neoplasms/radiotherapy , DNA Repair/genetics , Cell Line, Tumor , Adenocarcinoma of Lung/genetics , Adenocarcinoma of Lung/radiotherapy , Radiation Tolerance/genetics , Carcinogenesis/genetics
3.
Respir Res ; 24(1): 25, 2023 Jan 24.
Article in English | MEDLINE | ID: mdl-36694200

ABSTRACT

BACKGROUND: Radiation-induced lung injury (RILI) is the most common and serious complication of chest radiotherapy. However, reported radioprotective agents usually lead to radiation resistance in tumor cells. The key to solving this problem is to distinguish between the response of tumor cells and normal lung epithelial cells to radiation damage. METHODS: RNA-Seq was used to recognize potential target of alleviating the progression of RILI as well as inhibiting tumor growth. The activation of NLRP3 inflammasome in lung epithelial cells was screened by qRT-PCR, western blotting, immunofluorescence, and ELISA. An in vivo model of RILI and in vitro conditioned culture model were constructed to evaluate the effect of NLRP3/interleukin-1ß on fibroblasts activation. ROS, ATP, and (NADP)+/NADP(H) level in lung epithelial cells was detected to explore the mechanism of NLRP3 inflammasome activation. The lung macrophages of the mice were deleted to evaluate the role of lung epithelial cells in RILI. Moreover, primary cells were extracted to validate the results obtained from cell lines. RESULTS: NLRP3 activation in epithelial cells after radiation depends on glycolysis-related reactive oxygen species accumulation. DPYSL4 is activated and acts as a negative regulator of this process. The NLRP3 inflammasome triggers interleukin-1ß secretion, which directly affects fibroblast activation, proliferation, and migration, eventually leading to lung fibrosis. CONCLUSIONS: Our study suggests that NLRP3 inflammasome activation in lung epithelial cells is essential for radiation-induced lung injury. These data strongly indicate that targeting NLRP3 may be effective in reducing radiation-induced lung injury in clinical settings.


Subject(s)
Inflammasomes , Lung Injury , Radiation Injuries, Experimental , Animals , Mice , Epithelial Cells/metabolism , Inflammasomes/metabolism , Interleukin-1beta/genetics , Interleukin-1beta/metabolism , Lung/metabolism , Lung Injury/etiology , Lung Injury/genetics , Lung Injury/metabolism , NADP/metabolism , NADP/pharmacology , NLR Family, Pyrin Domain-Containing 3 Protein/genetics , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Reactive Oxygen Species/metabolism , Radiation Injuries, Experimental/complications , Radiation Injuries, Experimental/genetics , Radiation Injuries, Experimental/metabolism
4.
Respir Res ; 20(1): 248, 2019 Nov 07.
Article in English | MEDLINE | ID: mdl-31699089

ABSTRACT

BACKGROUND: Small cell lung cancer (SCLC) is a highly aggressive lung cancer subtype with poor survival and limited treatment options. Sequencing results have revealed gene mutations associated with SCLC, however, the correlation between the genomic alterations and clinical prognosis of SCLC is yet unclear. METHODS: Targeted next-generation sequencing of 62 cancer related genes was performed on 53 SCLC samples. The correlations between clinical outcomes and genomic alterations were analyzed. RESULTS: 38/62 (61.3%) candidate genes harbored some alterations, while all the SCLC samples carried at least 3 gene mutations. The most common nonsynonymous mutations included ERBB2 (95.9%), CREBBP (95.9%), and TP53 (77.6%). The median nonsynonymous tumor mutation burden (TMB) was 21.7 mutations/Mb (rang, 9.3-55.9). High TMB (> 21 mutations/Mb) was good prognostic factor in overall survival (OS) (21.7 vs. 10.4 months, P = 0.012). Multivariate analysis showed that high TMB was an independent prognostic factor. The overall survival (OS) of patients carrying KIAA1211 mutation was significantly longer than those with wild-type KIAA1211 (P < 0.001). CONCLUSIONS: The current study highlights the potential role of genomic alterations for the prognosis of SCLC. Higher TMB was associated with a better prognosis, and KIAA1211 might be a good prognostic factor in SCLC.


Subject(s)
Biomarkers, Tumor/genetics , Lung Neoplasms/genetics , Microfilament Proteins/genetics , Mutation , Small Cell Lung Carcinoma/genetics , Female , Genetic Predisposition to Disease , Humans , Lung Neoplasms/mortality , Lung Neoplasms/pathology , Lung Neoplasms/therapy , Male , Middle Aged , Neoplasm Staging , Phenotype , Pregnancy , Progression-Free Survival , Risk Assessment , Risk Factors , Small Cell Lung Carcinoma/mortality , Small Cell Lung Carcinoma/pathology , Small Cell Lung Carcinoma/therapy
5.
Anticancer Drugs ; 30(3): 241-250, 2019 03.
Article in English | MEDLINE | ID: mdl-30640793

ABSTRACT

Cardamonin, a natural chalcone compound, has been reported to exert anticancer effects in several cancers. However, the specific pharmacological actions of cardamonin on human non-small-cell lung cancer (NSCLC) and the potential mechanisms still remain obscure. Here, we investigated the antineoplastic role of cardamonin in NSCLC both in vitro and in vivo. The proliferation of five NSCLC cell lines was inhibited in a dose-dependent and time-dependent manner with cardamonin treatment. In A549 and H460 cells, cardamonin induced apoptosis by activating caspase-3, upregulating Bax, and downregulating Bcl-2. In addition, cardamonin arrested cells in the G2/M phase and inhibited the expression levels of cyclin D1/CDK4. Moreover, cell migration and invasion were suppressed by reversing epithelial-mesenchymal transition with cardamonin treatment. Further study showed that cardamonin reduced the phosphorylation levels of the downstream effectors of phosphoinositide 3-kinase (PI3K), including protein kinase-B (Akt/PKB) and mammalian target of rapamycin (mTOR). Moreover, in the H460 xenograft model, cardamonin significantly retarded tumor growth. Also, in tumor tissues, we found that cardamonin treatment decreased the expression rates of Ki-67, p-Akt, and p-mTOR. These data suggest that cardamonin suppressed NSCLC cell proliferation and inhibited metastasis partly by restraining the PI3K/Akt/mTOR pathway and it might be an effective therapeutic compound for NSCLC in the future.


Subject(s)
Carcinoma, Non-Small-Cell Lung/drug therapy , Chalcones/pharmacology , Gene Expression Regulation, Neoplastic/drug effects , Lung Neoplasms/drug therapy , Phosphatidylinositol 3-Kinases/chemistry , Proto-Oncogene Proteins c-akt/antagonists & inhibitors , TOR Serine-Threonine Kinases/antagonists & inhibitors , Animals , Apoptosis , Carcinoma, Non-Small-Cell Lung/metabolism , Carcinoma, Non-Small-Cell Lung/secondary , Cell Movement , Cell Proliferation , Female , Humans , Lung Neoplasms/metabolism , Lung Neoplasms/pathology , Mice , Mice, Inbred BALB C , Mice, Nude , Phosphorylation , Signal Transduction , Tumor Cells, Cultured , Xenograft Model Antitumor Assays
6.
Biol Res ; 52(1): 22, 2019 Apr 16.
Article in English | MEDLINE | ID: mdl-30992075

ABSTRACT

BACKGROUND: Tumor microenvironment (TME) plays a vital role in determining the outcomes of radiotherapy. As an important component of TME, vascular endothelial cells are involved in the perivascular resistance niche (PVRN), which is formed by inflammation or cytokine production induced by ionizing radiation (IR). Protein kinase CK2 is a constitutively active serine/threonine kinase which plays a vital role in cell proliferation and inflammation. In this study, we investigated the potential role of CK2 in PVRN after IR exposure. RESULT: Specific CK2 inhibitors, Quinalizarin and CX-4945, were employed to effectively suppressed the kinase activity of CK2 in human umbilical vein endothelial cells (HUVECs) without affecting their viability. Results showing that conditioned medium from IR-exposed HUVECs increased cell viability of A549 and H460 cells, and the pretreatment of CK2 inhibitors slowed down such increment. The secretion of IL-8 and IL-6 in HUVECs was induced after exposure with IR, but significantly inhibited by the addition of CK2 inhibitors. Furthermore, IR exposure elevated the nuclear phosphorylated factor-κB (NF-κB) p65 expression in HUVECs, which was a master factor regulating cytokine production. But when pretreated with CK2 inhibitors, such elevation was significantly suppressed. CONCLUSION: This study indicated that protein kinase CK2 is involved in the key process of the IR induced perivascular resistant niche, namely cytokine production, by endothelial cells, which finally led to radioresistance of non-small cell lung cancer cells. Thus, the inhibition of CK2 may be a promising way to improve the outcomes of radiation in non-small cell lung cancer cells.


Subject(s)
Carcinoma, Non-Small-Cell Lung/radiotherapy , Casein Kinase II/antagonists & inhibitors , Endothelial Cells/radiation effects , Lung Neoplasms/drug therapy , Protein Kinase Inhibitors/pharmacology , Anthraquinones/pharmacology , Blotting, Western , Cytokines/biosynthesis , Endothelium, Vascular/cytology , Humans , Naphthyridines/pharmacology , Phenazines
7.
Cell Physiol Biochem ; 45(5): 1827-1839, 2018.
Article in English | MEDLINE | ID: mdl-29510376

ABSTRACT

BACKGROUND/AIMS: Recently, endothelial-like cells originating directly from tumor cells have been revealed. However, the mechanism remains unclear. ETS-1 (E26 transformation specific-1), a key transcription factor in the generation and maturation of ECs (endothelial cells), has been reported to be overexpressed in several cancers. Here, we reveal novel regulation of the endothelial-like differentiation of NSCLC (non-small cell lung cancer) cells by ETS-1. METHODS: We up-regulated the expression of ETS-1 in NSCLC cell lines by H2O2 or lentiviral vector. Endothelial phenotypes, such as vWF (von Willebrand factor) and VE-cadherin were examined by Western blot analysis and immunofluorescence assay. Tube formation assay and phagocytotic activity assay were performed to evaluate ECs' specific features on NSCLC cells. The effect of ETS-1 on metastasis was determined by wound healing assays, transwell assays and a xenograft tumor model. To explore the role of ETS-1 in the initiation and progression of NSCLC, we examined ETS-1 levels in NSCLC cancerous tissues and paired adjacent normal tissues by immunohistochemstry and analyzed the relationship between ETS-1 levels and clinicopathological parameters, as well as patient survival. Kaplan Meier plotter database was used to assess the prognostic value of ETS-1 in NSCLC. The association between ETS-1 levels and MVD (microvessel density) was analyzed to determine their role in angiogenesis. RESULTS: With ETS-1 up-regulation, the expression of vWF and VE-cadherin was increased in NSCLC cells. Additionally, cells adopted several ECs' specific features, including enhanced tube formation ability and uptake of Dil-ac-LDL (acetylated low-density lipoprotein) and lectin. ETS-1 up-regulation also promoted cell migration, invasion and adhesion. In addition, xenograft mice arising from ETS-1 over-expressing cells had more liver metastases. In the clinical specimens, ETS-1 expression was significantly higher in NSCLC cancerous tissues than adjacent nontumorous tissues and positively associated with tumor size, T stage, N stage and clinical stage. Patients with high levels of ETS-1 expression had significantly poorer OS (overall survival) and FP (first progression) than those with low expression. Furthermore, there was a positive correlation between ETS-1 level and MVD. CONCLUSION: Collectively, our data reveal that ETS-1 can induce the differentiation of tumor cells into endothelial-like cells and further promote metastatic dissemination in NSCLC.


Subject(s)
Carcinoma, Non-Small-Cell Lung/pathology , Lung Neoplasms/pathology , Proto-Oncogene Protein c-ets-1/metabolism , A549 Cells , Adult , Aged , Aged, 80 and over , Animals , Antigens, CD/metabolism , Cadherins/metabolism , Carcinoma, Non-Small-Cell Lung/metabolism , Carcinoma, Non-Small-Cell Lung/mortality , Cell Differentiation/drug effects , Cell Line, Tumor , Cell Movement/drug effects , Female , Humans , Hydrogen Peroxide/pharmacology , Kaplan-Meier Estimate , Lectins/metabolism , Liver Neoplasms/pathology , Liver Neoplasms/secondary , Lung Neoplasms/metabolism , Lung Neoplasms/mortality , Male , Mice , Mice, Nude , Middle Aged , Neoplasm Staging , Proto-Oncogene Protein c-ets-1/antagonists & inhibitors , Proto-Oncogene Protein c-ets-1/genetics , RNA Interference , RNA, Small Interfering/metabolism , Transplantation, Heterologous , Up-Regulation/drug effects , von Willebrand Factor/metabolism
8.
J Nanosci Nanotechnol ; 18(6): 4360-4365, 2018 Jun 01.
Article in English | MEDLINE | ID: mdl-29442788

ABSTRACT

Hydroxyapatite nanoparticles were prepared by hydrothermal method using calcium nitrate and phosphoric acid as precursors and ammonia aqueous solution as a pH value adjustor. The 3D-printed porous Ti6Al4V and CoCrMo alloy scaffolds were effectively coated with hydroxyapatite nanoparticles in the hydrothermal synthesis process by deposition method. Coating hydroxyapatite nanoparticles on the implant surfaces increased their biocompatibility and bioactivity. HAP-deposited Ti6Al4V or HAP-deposited CoCrMo scaffold induced no statistical increase in terms of apoptosis in hFOB1.19 cells compared with bare Ti6Al4V or bare CoCrMo. Interestingly, HAP coating groups presented CCK-8 values compared with bare groups suggesting that HAP could enhance cell proliferation.


Subject(s)
Durapatite , Nanoparticles , Osteoblasts/drug effects , Titanium , Alloys , Coated Materials, Biocompatible , Humans , Materials Testing , Tissue Scaffolds
9.
Biochem Biophys Res Commun ; 492(3): 447-452, 2017 10 21.
Article in English | MEDLINE | ID: mdl-28842255

ABSTRACT

Vasculogenic mimicry (VM), an endothelial-independent tumor vascularization phenomenon representing functional tumor plasticity, might be the culprit behind the poor clinical outcome in classic antiangiogenesis treatment. However, the mechanism underlying VM needs to be elucidated. Cyclin-dependent kinase 5 (CDK5) has been recognized as a key factor in regulating migration and neuronal plasticity. Recently, CDK5 was associated with tumor migration and invasion and its expression levels correlated with poor clinical prognosis, indicating its important role in tumor cell plasticity. In this study, we determined the presence of VM network in the lung cancer cell line A549 by tube formation assay. Selective inhibition of CDK5 expression by roscovitine or siRNA significantly decreased VM formation in A549 cells both in vitro and in vivo and retarded tumor growth. To investigate the possible mechanism, we detected the downstream pathway of CDK5 by Western blotting and immunohistochemistry. We found that CDK5 silencing led to significant decrease in FAKSer732 and AKTSer472 phosphorylation level. Further studies showed that FAK knockdown impaired VM formation and deregulated cytoskeleton transformation of A549 cells. And these effects caused by FAK silence couldn't be reversed by adding CDK5 recombinant protein. This study indicates that CDK5 kinase activates the FAK/AKT signaling pathway to generate VM in a lung cancer cell line, which can help us develop potential therapeutic strategies against vessel-positive tumors.


Subject(s)
Carcinoma, Non-Small-Cell Lung/metabolism , Cyclin-Dependent Kinase 5/metabolism , Focal Adhesion Kinase 1/metabolism , Lung Neoplasms/metabolism , Neovascularization, Pathologic/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Signal Transduction , Humans , Tumor Cells, Cultured
11.
Exp Cell Res ; 328(1): 118-131, 2014 Oct 15.
Article in English | MEDLINE | ID: mdl-25149679

ABSTRACT

In mammalian central nervous system (CNS), the integrity of the blood-spinal cord barrier (BSCB), formed by tight junctions (TJs) between adjacent microvascular endothelial cells near the basement membrane of capillaries and the accessory structures, is important for relatively independent activities of the cellular constituents inside the spinal cord. The barrier function of the BSCB are tightly regulated and coordinated by a variety of physiological or pathological factors, similar with but not quite the same as its counterpart, the blood-brain barrier (BBB). Herein, angiopoietin 1 (Ang1), an identified ligand of the endothelium-specific tyrosine kinase receptor Tie-2, was verified to regulate barrier functions, including permeability, junction protein interactions and F-actin organization, in cultured spinal cord microvascular endothelial cells (SCMEC) of rat through the activity of Akt. Besides, these roles of Ang1 in the BSCB in vitro were found to be accompanied with an increasing expression of epidermal growth factor receptor pathway substrate 8 (Eps8), an F-actin bundling protein. Furthermore, the silencing of Eps8 by lentiviral shRNA resulted in an antagonistic effect vs. Ang1 on the endothelial barrier function of SCMEC. In summary, the Ang1-Akt pathway serves as a regulator in the barrier function modulation of SCMEC via the actin-binding protein Eps8.


Subject(s)
Adaptor Proteins, Signal Transducing/metabolism , Angiopoietin-1/metabolism , Endothelium, Vascular/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Spinal Cord/metabolism , Adaptor Proteins, Signal Transducing/antagonists & inhibitors , Adaptor Proteins, Signal Transducing/genetics , Animals , Blotting, Western , Cell Membrane Permeability , Cells, Cultured , Electric Conductivity , Endothelium, Vascular/cytology , Fluorescent Antibody Technique , Immunoprecipitation , RNA, Small Interfering/genetics , Rats , Rats, Sprague-Dawley , Spinal Cord/cytology
12.
Arch Orthop Trauma Surg ; 134(1): 1-7, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24202410

ABSTRACT

INTRODUCTION: Laminoplasty and skip laminectomy are two specific posterior surgical approaches for multilevel cervical spondylotic myelopathy. The objective of this study was to perform a systematic review comparing the clinical results and complications of laminoplasty and skip laminectomy in the treatment of multilevel cervical spondylotic myelopathy. MATERIALS AND METHODS: We reviewed and analyzed papers published from January 1969 to December 2012 through the Mediline, Embase, Cochrane review library, and other databases regarding the comparison between laminoplasty and skip laminectomy for multilevel cervical spondylotic myelopathy. RESULTS: One randomized controlled trial and three non-randomized controlled trials were included in this systematic review. In three studies, the preoperative and postoperative JOA score was similar in both laminoplasty and skip laminectomy groups. In addition, for recovery rate, there was no significant difference between the groups. One study reported that, regarding SF12 scores, there was no significant difference in physical health and mental health after surgery. However, regarding cervical pain, the skip laminectomy group was better than the laminoplasty group significantly. No difference was presented in postoperative ROM and the cervical lordosis between the groups. But the ROM % (post/pre) was reported to be significantly better in the skip laminectomy group in three studies. Less blood loss and shorter operation time were observed in skip laminectomy rather than laminoplasty. CONCLUSIONS: Based on the results above, the skip laminectomy group presented better outcomes in a variety of aspects: ROM % (post/pre), complication rate, surgical trauma, etc. However, as limited study samples were included in the paper, a claim of superiority of the two approaches could not be justified. Further studies are required on the comparison between laminoplasty and skip laminectomy.


Subject(s)
Laminectomy/methods , Spinal Cord Diseases/surgery , Spondylosis/surgery , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged
13.
Curr Mol Pharmacol ; 17: e18761429274883, 2024.
Article in English | MEDLINE | ID: mdl-38389417

ABSTRACT

Guanine nucleotide exchange factor H1 (GEF-H1) is a unique protein modulated by the GDP/GTP exchange. As a regulator of the Rho-GTPase family, GEF-H1 can be activated through a microtubule-depended mechanism and phosphorylation regulation, enabling it to perform various pivotal biological functions across multiple cellular activities. These include the regulation of Rho-GTPase, cytoskeleton formation, cellular barrier, cell cycle, mitosis, cell differentiation, and vesicle trafficking. Recent studies have revealed its crucial effect on the tumor microenvironment (TME) components, promoting tumor initiation and progress. Consequently, an in-depth exploration of GEF-H1's biological roles and association with tumors holds promise for its potential as a valuable molecular target in tumor treatment.


Subject(s)
Neoplasms , rhoA GTP-Binding Protein , Humans , Rho Guanine Nucleotide Exchange Factors/metabolism , rhoA GTP-Binding Protein/metabolism , Microtubules/metabolism , Proteins , Neoplasms/metabolism , Tumor Microenvironment
14.
Int J Biol Macromol ; 269(Pt 2): 132102, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38729465

ABSTRACT

Optically pure 1,2,3,4-tetrahydroquinolines (THQs) represent a class of important motifs in many natural products and pharmaceutical agents. While recent advances on redox biocatalysis have demonstrated the great potential of amine oxidases, all the transformations focused on 2-substituted THQs. The corresponding biocatalytic method for the preparation of chiral 4-substituted THQs is still challenging due to the poor activity and stereoselectivity of the available enzyme. Herein, we developed a biocatalytic kinetic resolution approach for enantiodivergent synthesis of 4-phenyl- or alkyl-substituted THQs. Through structure-guided protein engineering of cyclohexylamine oxidase derived from Brevibacterium oxidans IH-35 A (CHAO), the variant of CHAO (Y215H/Y214S) displayed improved specific activity toward model substrate 4-phenyl substituted THQ (0.14 U/mg, 13-fold higher than wild-type CHAO) with superior (R)-stereoselectivity (E > 200). Molecular dynamics simulations show that CHAO Y215H/Y214S allows a suitable substrate positioning in the expanded binding pocket to be facilely accessed, enabling enhanced activity and stereoselectivity. Furthermore, a series of 4-alkyl-substituted THQs can be transformed by CHAO Y215H/Y214S, affording R-isomers with good yields (up to 50 %) and excellent enantioselectivity (up to ee > 99 %). Interestingly, the monoamine oxidase from Pseudomonas fluorescens Pf0-1 (PfMAO1) with opposite enantioselectivity was also mined. Together, this system enriches the kinetic resolution methods for the synthesis of chiral THQs.


Subject(s)
Quinolines , Kinetics , Stereoisomerism , Quinolines/chemistry , Biocatalysis , Brevibacterium/enzymology , Substrate Specificity , Molecular Dynamics Simulation , Monoamine Oxidase/metabolism , Monoamine Oxidase/chemistry
15.
Int J Biol Macromol ; 278(Pt 4): 134994, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39181367

ABSTRACT

l-threonine aldolase (LTA) catalyzes the synthesis of ß-hydroxy-α-amino acids, which are important chiral intermediates widely used in the fields of pharmaceuticals and pesticides. However, the limited thermostability of LTA hinders its industrial application. Furthermore, the trade-off between thermostability and activity presents a challenge in the thermostability engineering of this enzyme. This study proposes a strategy to regulate the rigidity of LTA's V-shaped subunit by modifying its opening and hinge regions, distant from the active center, aiming to mitigate the trade-off. With LTA from Bacillus nealsonii as targeted enzyme, a total of 25 residues in these two regions were investigated by directed evolution. Finally, mutant G85A/M207L/A12C was obtained, showing significantly enhanced thermostability with a 20 °C increase in T5060 to 66 °C, and specific activity elevated by 34 % at the optimum temperature. Molecular dynamics simulations showed that the newly formed hydrophobicity and hydrogen bonds improved the thermostability and boosted proton transfer efficiency. This work enhances the thermostability of LTA while preventing the loss of activity. It opens new avenues for the thermostability engineering of other industrially relevant enzymes with active center located at the interface of subunits or domains.


Subject(s)
Enzyme Stability , Molecular Dynamics Simulation , Mutation , Temperature , Bacillus/enzymology , Bacillus/genetics , Hydrogen Bonding , Aldehyde-Lyases/chemistry , Aldehyde-Lyases/genetics , Aldehyde-Lyases/metabolism , Catalytic Domain , Kinetics , Protein Subunits/chemistry , Protein Subunits/genetics , Protein Subunits/metabolism , Protein Engineering/methods
16.
Mol Plant Pathol ; 25(8): e13502, 2024 Aug.
Article in English | MEDLINE | ID: mdl-39118198

ABSTRACT

Banana Fusarium wilt, caused by Fusarium oxysporum f. sp. cubense tropical race 4 (Foc TR4), is a major disease of banana plants worldwide. Effector proteins play critical roles in banana-Foc TR4 interaction. Our previous studies highlighted a ribonuclease protein belonging to the T2 family (named as FocRnt2) in the Foc TR4 secretome, which was predicted to be an effector. However, its biological function in Foc TR4 infection is still unclear. Herein, we observed significant expression of FocRnt2 during the early stage of fungal infection in planta. A yeast signal sequence trap assay showed that FocRnt2 contained a functional signal peptide for secretion. FocRnt2 possessed ribonuclease activity that could degrade the banana total RNA in vitro. Subcellular localization showed that FocRnt2 was localized in the nucleus and cytoplasm of Nicotiana benthamiana leaves. Transient expression of FocRnt2 suppressed the expression of salicylic acid- and jasmonic acid-signalling marker genes, reactive oxygen species accumulation, and BAX-mediated cell death in N. benthamiana. FocRnt2 deletion limited fungal penetration, reduced fusaric acid biosynthesis in Foc TR4, and attenuated fungal virulence against banana plants, but had little effect on Foc TR4 growth and sensitivity to various stresses. Furthermore, FocRnt2 deletion mutants induced higher expression of the defence-related genes in banana plants. These results suggest that FocRnt2 plays an important role in full virulence of Foc TR4, further improving our understanding of effector-mediated Foc TR4 pathogenesis.


Subject(s)
Fusarium , Musa , Nicotiana , Plant Diseases , Fusarium/pathogenicity , Virulence , Plant Diseases/microbiology , Musa/microbiology , Nicotiana/microbiology , Fungal Proteins/metabolism , Fungal Proteins/genetics , Ribonucleases/metabolism , Ribonucleases/genetics , Reactive Oxygen Species/metabolism , Endoribonucleases
17.
Transl Cancer Res ; 12(4): 904-912, 2023 Apr 28.
Article in English | MEDLINE | ID: mdl-37180651

ABSTRACT

Background: Anti-angiogenesis therapy has been a vital treatment option in a variety of cancers. Assessing the efficacy and safety of apatinib in patients with heavily pretreated end-stage cancer is essential. Methods: Thirty patients with end-stage cancer who were heavily pretreated were enrolled in this study. All patients received oral administration of apatinib (125-500 mg/d) between May 2015 and November 2016. Dose reduction or elevation was conducted based on adverse events and doctors' judgments. Results: Prior to the apatinib treatment, the enrolled patients received a median of 1.2 surgeries (range, 0-7), 1.6 sessions of radiotherapies (range, 0-6), and 10.2 cycles of chemotherapy (range, 0-60); 43.3% of patients had uncontrolled local lesions, 83.3% of patients had uncontrolled multiple metastases, and 30.0% of patients had both. After the treatment, 25 patients had valuable data, 6 (24.0%) patients achieved partial response (PR), and 12 (48.0%) patients had stable disease (SD). The disease control rate (DCR) was 72.0%. The PR and SD rates were 20.0% and 40.0%, respectively, and the DCR was 60.0% in the intent-to-treat (ITT) analysis. Meanwhile, the median progression-free survival (PFS) was 2.6 (range, 0.7-5.4) months, and the median overall survival (OS) was 3.8 (range, 1.0-12.0) months. Furthermore, the PR rate and DCR in patients with squamous cell cancer (SCC) were 45.5% and 81.8%, respectively; those in patients with adenocarcinoma (ADC) were 8.3% and 58.3%, respectively. The adverse events were generally mild. The most common adverse events were hyperbilirubinemia (53.3%), elevated transaminase (36.7%), anemia (30.0%), thrombocytopenia (30.0%), hematuria (30.0%), fatigue (26.7%), and leukopenia (20.0%). Conclusions: The results of this study demonstrate the efficacy and safety of apatinib and support the further development of apatinib as a potential treatment option for patients with heavily pretreated end-stage cancer.

18.
Int J Radiat Oncol Biol Phys ; 115(5): 1244-1256, 2023 04 01.
Article in English | MEDLINE | ID: mdl-36423742

ABSTRACT

PURPOSE: Tumor radiation resistance is the main obstacle to effective radiation therapy for patients with hepatocellular carcinoma (HCC). We identified the role of urea cycle key enzyme carbamoyl phosphate synthetase 1 (CPS1) in radioresistance of HCC and explored its mechanism, aiming to provide a novel radiosensitization strategy for the CPS1-deficiency HCC subtype. METHODS AND MATERIALS: The expression of CPS1 was measured by western blot and immunohistochemistry. Cell growth assay, EdU assay, cell apoptosis assay, cell cycle assay, clone formation assay, and subcutaneous tumor assay were performed to explore the relationship between CPS1 and radioresistance of HCC cells. Lipid metabonomic analysis was used for investigating the effects of CPS1 on lipid synthesis of HCC cells. RNA sequencing and coimmunoprecipitation assay were carried out to reveal the mechanism of CPS1 participating in the regulation of HCC radiation therapy resistance. Furthermore, 10074-G5, the specific inhibitor of c-Myc, was administered to HCC cells to investigate the role of c-Myc in CPS1-deficiency HCC cells. RESULTS: We found that urea cycle key enzyme CPS1 was frequently lower in human HCC samples and positively associated with the patient's prognosis. Functionally, the present study proved that CPS1 depletion could accelerate the development of HCC and induce radiation resistance of HCC in vitro and in vivo, and deficiency of CPS1 promoted the synthesis of some lipid molecules. Regarding the mechanism, we uncovered that inhibition of CPS1 upregulated CyclinA2 and CyclinD1 by stabilizing oncoprotein c-Myc at the posttranscriptional level and generated radioresistance of HCC cells. Moreover, inactivation of c-Myc using 10074-G5, a specific c-Myc inhibitor, could partially attenuate the proliferation and radioresistance induced by depletion of CPS1. CONCLUSIONS: Our results recapitulated that silencing CPS1 could promote HCC progression and radioresistance via c-Myc stability mediated by the ubiquitin-proteasome system, suggesting that targeting c-Myc in CPS1-deficiency HCC subtype may be a valuable radiosensitization strategy in the treatment of HCC.


Subject(s)
Carbamoyl-Phosphate Synthase I Deficiency Disease , Carcinoma, Hepatocellular , Liver Neoplasms , Humans , Carcinoma, Hepatocellular/radiotherapy , Carcinoma, Hepatocellular/metabolism , Carbamyl Phosphate , Liver Neoplasms/radiotherapy , Liver Neoplasms/metabolism , Carbamoyl-Phosphate Synthase (Ammonia)/chemistry , Carbamoyl-Phosphate Synthase (Ammonia)/genetics , Carbamoyl-Phosphate Synthase (Ammonia)/metabolism , Carbamoyl-Phosphate Synthase I Deficiency Disease/genetics , Carbamoyl-Phosphate Synthase I Deficiency Disease/metabolism , Carbamoyl-Phosphate Synthase I Deficiency Disease/pathology , Urea , Lipids , Cell Line, Tumor
19.
J Thorac Dis ; 15(12): 6858-6867, 2023 Dec 30.
Article in English | MEDLINE | ID: mdl-38249881

ABSTRACT

Background: Awake prone positioning (APP) is broadly implemented in patients with severe acute respiratory syndrome coronavirus 2 related disease [coronavirus disease 2019 (COVID-19)] admitted to hospital with severe respiratory distress syndrome. This prospective observational study aimed to explore the factors influencing the implementation of APP in patients with acute respiratory failure due to COVID-19. Methods: Patients with COVID-19, all hospitalized with positive X-ray findings and oxygen supplementation requirement, in the Respiratory Step-Down Unit of the Peking University Third Hospital between January 6th, 2023, and January 20th, 2023, were included in this study. Data regarding basic information, activities of daily living (ADLs) scores, oxygen therapy, vital signs, and duration of APP were collected to investigate the factors influencing prone positioning. Results: Among the 134 patients included, 55.2% showed an improvement in oxygen saturation 1 hour after APP. Logistic regression revealed that the pre-APP heart rate (HR) [odds ratio (OR) =1.032; P=0.046] and peripheral oxygen saturation (SpO2) (OR =0.720; P<0.001) were the associated factors of the improvement in SpO2 after treatment. Multiple linear regression revealed that the ADL scores and pre-APP respiratory rate (RR) were the associated factors of the duration of prone positioning (P<0.01). The APP technical steering group effectively improved duration of APP. Conclusions: Patients with low SpO2 and increased HR before treatment showed greater improvement in oxygen saturation. Patients with lower tolerance to ADL but lower RRs were those to demonstrate a longer duration of prone positioning. This is pointing towards establishing the most favorable time window for APP during the course of COVID-19: after the ADLs have already decreased, but before significant tachypnea has appeared.

20.
Front Plant Sci ; 13: 1018616, 2022.
Article in English | MEDLINE | ID: mdl-36325552

ABSTRACT

Rice blast caused by Magnaporthe oryzae is one of the most important diseases of rice. Elicitors secreted by M. oryzae play important roles in the interaction with rice to facilitate fungal infection and disease development. In recent years, several elicitor proteins have been identified in M. oryzae, and their functions and importance are increasingly appreciated. In this study, we purified a novel elicitor-activity protein from M. oryzae, which was further identified as a vanadium chloroperoxidase (MoVcpo) by MAIDL TOF/TOF MS. The purified MoVcpo induced reactive oxygen species (ROS) accumulation in host cells, up-regulated the expression of multiple defense-related genes, thus significantly enhancing rice resistance against M. oryzae. These results suggested that MoVcpo functions as a pathogen-associated molecular pattern (PAMP) to trigger rice immunity. Furthermore, MoVcpo was highly expressed in the early stage of M. oryzae infection. Deletion of MoVcpo affected spore formation, conidia germination, cell wall integrity, and sensitivity to osmotic stress, but not fungal growth. Interestingly, compared with the wild-type, inoculation with MoVcpo deletion mutant on rice led to markedly induced ROS accumulation, increased expression of defense-related genes, but also lower disease severity, suggesting that MoVcpo acts as both an elicitor activating plant immune responses and a virulence factor facilitating fungal infection. These findings reveal a novel role for vanadium chloroperoxidase in fungal pathogenesis and deepen our understanding of M. oryzae-rice interactions.

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