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Background: M2 macrophages can promote the progression of castration-resistant prostate cancer (CRPC), but the specific mechanism is still unclear. Therefore, we are preliminarily exploring the molecular mechanism by which M2 macrophages regulate the progression of CRPC. Methods: The genes positively correlated with CRPC and with the most significant differences in the GEO32269 dataset were obtained. Database and immunofluorescence experiments were used to validate the localization of secreted phosphoprotein 1 (SPP1) in localized prostate cancer (PCa), hormone-sensitive prostate cancer (HSPC), and CRPC tumor tissues. The function of SPP1 in M2 macrophages was verified through cell scratch, Transwell, and an orthotopic PCa model. PCa database and Western blot were used to verify the relationship between SPP1 and matrix metallopeptidase 9 (MMP9), as well as the ability of MMP9 in M2 macrophages to promote epithelial-mesenchymal transition (EMT) in PCa cells. Results: The primary localization of SPP1 in prostate and CRPC tissues is in macrophages. Silencing SPP1 expression in M2 macrophages promotes their polarization towards the M1 phenotype and significantly inhibits the malignant progression of PCa in vitro and in vivo. SPP1 promotes the expression of MMP9 through the PI3K/AKT signaling pathway in M2 macrophages. Furthermore, MMP9 enhances the EMT and migratory capabilities of PC3 cells by activating the TGFß signaling pathway. Conclusions: We have found that the high expression of SPP1 in M2 macrophages promotes the progression of CRPC through cell-cell interactions. These findings can contribute to the development of novel therapeutic approaches for combating this deadly disease.
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Nucleophosmin (NPM1) is a key nucleolar protein released from the nucleolus in response to stress stimuli. NPM1 functions as a stress regulator with nucleic acid and protein chaperone activities, rapidly shuttling between the nucleus and cytoplasm. NPM1 is ubiquitously expressed in tissues and can be found in the nucleolus, nucleoplasm, cytoplasm, and extracellular environment. It plays a central role in various biological processes such as ribosome biogenesis, cell cycle regulation, cell proliferation, DNA damage repair, and apoptosis. In addition, it is highly expressed in cancer cells and solid tumors, and its mutation is a major cause of acute myeloid leukemia (AML). This review focuses on NPM1's structural features, functional diversity, subcellular distribution, and role in stress modulation.
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Nucléolo Celular , Proteínas Nucleares , Nucleofosmina , Estresse Fisiológico , Humanos , Proteínas Nucleares/metabolismo , Nucléolo Celular/metabolismo , Animais , Fosfoproteínas/metabolismoRESUMO
Nonreceptor tyrosine phosphatases (NTPs) play an important role regulating protein phosphorylation and have been proposed as attractive therapeutic targets for cancer and metabolic diseases. We have previously identified that 3-Hydroxy-1,2,3-benzotriazin-4(3H)-one (HODHBt) enhanced STAT activation upon cytokine stimulation leading to increased reactivation of latent HIV and effector functions of NK and CD8 T cells. Here, we demonstrated that HODHBt interacts with and inhibits the NTPs PTPN1 and PTPN2 through a mixed inhibition mechanism. We also confirmed that PTPN1 and PTPN2 specifically control the phosphorylation of different STATs. The small molecule ABBV-CLS-484 (AC-484) is an active site inhibitor of PTPN1 and PTPN2 currently in clinical trials for advanced solid tumors. We compared AC-484 and HODHBt and found similar effects on STAT5 and immune activation albeit with different mechanisms of action leading to varying effects on latency reversal. Our studies provide the first specific evidence that enhancing STAT phosphorylation via inhibition of PTPN1 and PTPN2 is an effective tool against HIV.
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Idiopathic pulmonary fibrosis (IPF) is a fatal pulmonary disease that requires further investigation to understand its pathogenesis. The present study demonstrated that secreted phosphoprotein 1 (SPP1) was aberrantly highly expressed in the lung tissue of patients with IPF and was significantly positively associated with macrophage and Tcell activity. Cell localization studies revealed that SPP1 was primarily overexpressed in macrophages, rather than in T cells. Functionally, knocking down SPP1 expression in vitro inhibited the secretion of fibrosisrelated factors and M2 polarization in macrophages. Furthermore, knocking down SPP1 expression inhibited the macrophageinduced epithelialtomesenchymal transition in both epithelial and fibroblastic cells. Treatment with SPP1 inhibitors in vivo enhanced lung function and ameliorated pulmonary fibrosis. Mechanistically, SPP1 appears to promote macrophage M2 polarization by regulating the JAK/STAT3 signaling pathway both in vitro and in vivo. In summary, the present study found that SPP1 promotes M2 polarization of macrophages through the JAK2/STAT3 signaling pathway, thereby accelerating the progression of IPF. Inhibition of SPP1 expression in vivo can effectively alleviate the development of IPF, indicating that SPP1 in macrophages may be a potential therapeutic target for IPF.
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Fibrose Pulmonar Idiopática , Janus Quinase 2 , Macrófagos , Osteopontina , Fator de Transcrição STAT3 , Transdução de Sinais , Fator de Transcrição STAT3/metabolismo , Janus Quinase 2/metabolismo , Fibrose Pulmonar Idiopática/patologia , Fibrose Pulmonar Idiopática/metabolismo , Macrófagos/metabolismo , Humanos , Animais , Masculino , Camundongos , Osteopontina/metabolismo , Osteopontina/genética , Progressão da Doença , Transição Epitelial-Mesenquimal/genética , Feminino , Camundongos Endogâmicos C57BL , Pessoa de Meia-IdadeRESUMO
Background: Recurrence and metastasis are the major obstacles affecting the therapeutic efficacy and clinical outcomes for patients with esophageal carcinoma (ESCA). Secreted phosphoprotein 1 (SPP1) is considered as a hub gene in ESCA and is negatively associated with disease-free survival (DFS) in ESCA. However, the exact roles and underlying mechanisms remain elusive. This study aims to examine the roles of SPP1 on ESCA, and elucidate the potential mechanisms. Methods: Bioinformatics were used to analyze the expression of SPP1 in ESCA tissues, and its relations with clinicopathological characteristics and clinical prognosis in patients with ESCA based on The Cancer Genome Atlas (TCGA) dataset. Loss-of-function was conducted to examine the roles of SPP1 on malignant behaviors of ESCA cells by cell counting kit-8 (CCK8), plate clone, wound healing, and transwell assays. Gene set enrichment analysis (GSEA) was conducted to screen the pathways associated with SPP1 in ESCA. Then, the enriched pathway and the underlying mechanism were elucidated by western blotting, cell adhesion, and cell spreading assays. Lastly, Y15 [a specific inhibitor of focal adhesion kinase (FAK)] was used to examine its potential to inhibit tumor growth in ESCA cells. Results: SPP1 was upregulated in ESCA tissues compared to the adjacent nontumorous tissues, which was closely associated with clinical stage, lymph node metastasis, histological subtype, and p53 mutation. A high expression of SPP1 indicated a poor clinical prognosis in patients with ESCA. The knockdown of SPP1 inhibited cell proliferative, migratory, and invasive capacities in ESCA cells. GSEA indicated that the focal adhesion pathway was closely related with SPP1 in ESCA. Further studies confirmed that the knockdown of SPP1 suppressed cell adhesion ability and reduced the expression of p-FAK and p-Erk in ESCA cells. In addition, Y15 inhibited FAK autophosphorylation and dramatically inhibited cell proliferation, migration, and invasion in ESCA cells. Conclusions: SPP1 promotes tumor progression in ESCA by activating FAK/Erk pathway, and FAK is a potential therapeutic target to overcome tumor recurrence and metastasis of ESCA.
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Altered glycosylation is a common feature of cancer cells. Some subsets of glycans are found to be frequently enriched on the tumor cell surface and implicated in different tumor phenotypes. Among these, changes in sialylation have long been associated with metastatic cell behaviors such as invasion and enhanced cell survival. Sialylation typically exists in three prominent linkages: α2,3, α2,6, and α2,8, catalyzed by a group of sialyltransferases. The aberrant expression of all three linkages has been related to cancer progression. The increased α2,6 sialylation on N-glycans catalyzed by ß-galactoside α2,6 sialyltransferase 1 (ST6Gal1) is frequently observed in many cancers. In contrast, functions of α2,3 sialylation on N-glycans catalyzed by at least three ß-galactoside α2,3-sialyltransferases, ST3Gal3, ST3Gal4, and ST3Gal6 remain elusive due to a possibility of compensating for one another. In this minireview, we briefly describe functions of sialylation and recent findings that different α2,3 sialyltransferases specifically modify target proteins, as well as sialylation regulatory mechanisms vis a complex formation among integrin α3ß1, Golgi phosphoprotein 3 (GOLPH3), phosphatidylinositol 4-kinase IIα (PI4KIIα), focal adhesion kinase (FAK) and sialyltransferase, which suggests a new concept for the regulation of glycosylation in cell biology.
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Polissacarídeos , Sialiltransferases , Humanos , Sialiltransferases/metabolismo , Polissacarídeos/metabolismo , Animais , Glicosilação , Neoplasias/metabolismoRESUMO
Platelet concentrates (PC) are used to treat patients with thrombocytopenia and hemorrhage, but there is still the demand to find the optimal strategy for temperature-dependent storage of PC. Recently, we could show that cold storage for 1 h (short-term refrigeration) is sufficient to induce enhanced platelet responsiveness. The aim of this study was to investigate effects of cold storage on collagen-dependent activating signalling pathways in platelets from apheresis-derived PC (APC). APC on day 1 or day 2 of storage, were either continuously kept at room temperature (RT, 22 °C), or for comparison, additionally kept at cold temperature (CT, 4 °C) for 1 h. CD62P expression was determined by flow cytometry. Western Blot technique was used to analyze collagen-induced phosphorylation of p38, ERK1/2 or Akt/PKB and its inhibition by prostaglandin E1 (PGE1) or nitric monoxide donor. Adhesion of platelets on collagen-coated surfaces and intracellular phosphorylation of vasodilator-stimulated phosphoprotein (VASP) was visualized by immune fluorescence microscopy. CD62P expression was increased after short-term refrigeration. CT exposition for 1 h induced an elevation of basal ERK1/2 phosphorylation and an alleviation of PGE1- or DEA/NO-suppressed ERK1/2 phosphorylation in APC on day 1 and 2 of storage. Similar, but more moderate effects were observable for p38 phosphorylation. Akt/PKB phosphorylation was increased only in APC on day 2. Refrigeration for 1 h promoted platelet adhesion and reduced basal VASP phosphorylation in adherent platelets. The attenuation of inhibitory signalling in short-term refrigerated stored platelets is associated with enhanced reactivity of activating signalling pathways, especially ERK1/2. Functionally, these processes correlate with increased adhesion of refrigerated platelets on collagen-coated surfaces. The results help to further optimize temperature-dependent strategies for platelet storage.
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Plaquetas , Colágeno , Selectina-P , Transdução de Sinais , Humanos , Plaquetas/metabolismo , Colágeno/metabolismo , Selectina-P/metabolismo , Preservação de Sangue , Fosforilação , Refrigeração , Fosfoproteínas/metabolismo , Proteínas dos Microfilamentos/metabolismo , Moléculas de Adesão Celular/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Adesividade PlaquetáriaRESUMO
INTRODUCTION: We investigate the role of osteopontin (OPN) in participants with Pre-symptomatic Alzheimer's disease (AD), mild cognitive impairment (MCI), and in AD brains. METHODS: Cerebrospinal fluid (CSF) OPN, AD, and synaptic biomarker levels were measured in 109 cognitively unimpaired (CU), parental-history positive Pre-symptomatic Evaluation of Experimental or Novel Treatments for Alzheimer's Disease (PREVENT-AD) participants, and in 167 CU and 399 participants with MCI from the Alzheimer's Disease Neuroimaging Initiative (ADNI) cohort. OPN levels were examined as a function of amyloid beta (Aß) and tau positivity. Survival analyses investigated the link between OPN and rate of conversion to AD. RESULTS: In PREVENT-AD, CSF OPN was positively correlated with synaptic biomarkers. In PREVENT-AD and ADNI, OPN was elevated in CSF Aß42/40(+)/total tau(+) and CSF Aß42/40(+)/phosphorylated tau181(+) individuals. In ADNI, OPN was increased in Aß(+) positron emission tomography (PET) and tau(+) PET individuals, and associated with an accelerated rate of conversion to AD. OPN was elevated in autopsy-confirmed AD brains. DISCUSSION: Strong associations between CSF OPN and key markers of AD pathophysiology suggest a significant role for OPN in tau neurobiology, particularly in the early stages of the disease. HIGHLIGHTS: In the Pre-symptomatic Evaluation of Experimental or Novel Treatments for Alzheimer's Disease cohort, we discovered that cerebrospinal fluid (CSF) osteopontin (OPN) levels can indicate early synaptic dysfunction, tau deposition, and neuronal loss in cognitively unimpaired elderly with a parental history. CSF OPN is elevated in amyloid beta(+) positron emission tomography (PET) and tau(+) PET individuals. Elevated CSF OPN is associated with an accelerated rate of conversion to Alzheimer's disease (AD). Elevated CSF OPN is associated with an accelerated rate of cognitive decline on the Alzheimer's Disease Assessment Scale-Cognitive subscale 13, Montreal Cognitive Assessment, Mini-Mental State Examination, and Clinical Dementia Rating Scale Sum of Boxes. OPN mRNA and protein levels are significantly upregulated in the frontal cortex of autopsy-confirmed AD brains.
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BACKGROUND: Periodontitis is caused by a dysbiosis of oral bacteria resulting in alveolar bone destruction and teeth loss. The role of platelets in pathogenesis of periodontitis is a subject of research. The release of toxins from periodontitis-associated bacteria may influence platelet function and contribute to the modulation of hemostatic or inflammatory responses. Therefore, we explored platelet function upon exposure to defined toxins: leukotoxin A from Aggregatibacter actinomycetemcomitans (LtxA), a synthetic version of the C14-Tri-LAN-Gly peptide from Fusobacterium nucleatum (C14), and lipopolysaccharides from Porphyromonas gingivalis (LPS). METHODS: Light transmission aggregometry was performed after the addition of toxins to platelet-rich plasma in different doses. Flow cytometry was used to identify inhibitory effects of toxins by measuring phosphorylation of the vaso-dilator-stimulated phosphoprotein or to identify activating effects by the detection of CD62P expression. The release of chemokines derived from washed platelets was determined by immunoassays. RESULTS: Collagen-induced threshold aggregation values were diminished upon incubation with LtxA and C14, accompanied with an increase of vaso-dilator-stimulated phosphoprotein (VASP) phosphorylation, indicating platelet inhibition. In contrast, LPS did not affect aggregation but slightly enhanced CD62P expression under co-stimulation with low-dose thrombin pointing to slight platelet activation. The three toxins did not relevantly influence the secretion of chemokines. CONCLUSIONS: Although weak, the investigated toxins differently influenced human platelet function. LtxA and C14 mediated inhibitory effects, whereas LPS contributed to a slight activation of platelets. Further analysis of specific cellular responses mediated by bacterial toxins may render novel targets and suggestions for the treatment of periodontitis.
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Glycosylation and phosphorylation rank as paramount post-translational modifications, and their analysis heavily relies on enrichment techniques. In this work, a facile approach was developed for the one-step simultaneous enrichment and stepwise elution of glycoproteins and phosphoproteins. The core of this approach was the application of the novel titanium (IV) ion immobilized poly(glycidyl methacrylate) microparticles functionalized with dendrimer polyethylenimine and phytic acid. The microparticles possessed dual enrichment capabilities due to their abundant titanium ions and hydroxyl groups on the surface. They demonstrate rapid adsorption equilibrium (within 30 min) and exceptional adsorption capacity for ß-casein (1107.7 mg/g) and horseradish peroxidase (438.6 mg/g), surpassing that of bovine serum albumin (91.7 mg/g). Furthermore, sodium dodecyl sulfate-polyacrylamide gel electrophoresis was conducted to validate the enrichment capability. Experimental results across various biological samples, including standard protein mixtures, non-fat milk, and human serum, demonstrated the remarkable ability of these microparticles to enrich low-abundance glycoproteins and phosphoproteins from biological samples.
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Dendrímeros , Glicoproteínas , Fosfoproteínas , Polietilenoimina , Ácidos Polimetacrílicos , Titânio , Glicoproteínas/química , Fosfoproteínas/química , Polietilenoimina/química , Dendrímeros/química , Humanos , Titânio/química , Ácidos Polimetacrílicos/química , Interações Hidrofóbicas e Hidrofílicas , Propriedades de Superfície , Animais , Tamanho da Partícula , Adsorção , BovinosRESUMO
Aberrant activation of RAS/MAPK signaling is common in cancer, and efforts to inhibit pathway components have yielded drugs with promising clinical activities. Unfortunately, treatment-provoked adaptive resistance mechanisms inevitably develop, limiting their therapeutic potential. As a central node essential for receptor tyrosine kinase-mediated RAS activation, SHP2 has emerged as an attractive cancer target. Consequently, many SHP2 allosteric inhibitors are now in clinical testing. Here we discovered a previously unrecognized off-target effect associated with SHP2 allosteric inhibitors. We found that these inhibitors accumulate in the lysosome and block autophagic flux in an SHP2-independent manner. We showed that off-target autophagy inhibition by SHP2 allosteric inhibitors contributes to their antitumor activity. We also demonstrated that SHP2 allosteric inhibitors harboring this off-target activity not only suppress oncogenic RAS signaling but also overcome drug resistance such as MAPK rebound and protective autophagy in response to RAS/MAPK pathway blockage. Finally, we exemplified a therapeutic framework that harnesses both the on- and off-target activities of SHP2 allosteric inhibitors for improved treatment of mutant RAS-driven and drug-resistant malignancies such as pancreatic and colorectal cancers.
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Autofagia , Proteína Tirosina Fosfatase não Receptora Tipo 11 , Proteínas ras , Animais , Humanos , Camundongos , Regulação Alostérica/efeitos dos fármacos , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Autofagia/efeitos dos fármacos , Linhagem Celular Tumoral , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Neoplasias/metabolismo , Neoplasias/genética , Neoplasias/enzimologia , Proteína Tirosina Fosfatase não Receptora Tipo 11/antagonistas & inibidores , Proteína Tirosina Fosfatase não Receptora Tipo 11/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 11/genética , Proteínas ras/metabolismo , Proteínas ras/genética , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Pediatric burn injuries are a leading cause of morbidity with infections being the most common acute complication. Thermal injuries elicit a heightened cytokine response while suppressing immune function; however, the mechanisms leading to this dysfunction are still unknown. Our aim was to identify extracellular proteins and circulating phosphoprotein expression in the plasma after burn injury to predict the development of nosocomial infection (NI). Plasma was collected within 72 hours after injury from sixty-four pediatric burn subjects; of these, eighteen went on to develop a NI. Extracellular damage associated molecular proteins (DAMPs), FAS(APO), and protein kinase b (AKT) signaling phosphoproteins were analyzed. Subjects who went on to develop a NI had elevated high mobility group box 1 (HMGB1), heat shock protein 90 (HSP90), and FAS expression than those who did not develop a NI after injury (NoNI). Concurrently, phosphorylated (p-) AKT and mammalian target of rapamycin (p-mTOR) were elevated in those subjects who went on to develop a NI. Quadratic discriminant analysis revealed distinct differential profiles between NI and NoNI burn subjects using HSP90, FAS, and p-mTOR. The area under the receiver-operator characteristic curves displayed significant ability to distinguish between these two burn subject cohorts. These findings provide insight into predicting the signaling proteins involved in the development of NI in pediatric burn patients. Further these proteins show promise as a diagnostic tool for pediatric burn patients at risk of developing infection while additional investigation may lead to potential therapeutics to prevent NI.
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Background: Hypertrophic cardiomyopathy (HCM), identified as a primary cause of sudden cardiac death (SCD), intertwines with pulmonary hypertension (PH) to amplify cardiovascular morbidity. This complex synergy poses significant therapeutic challenges due to the absence of drugs specifically targeting their concurrent manifestation. This study seeks to unravel the molecular intricacies linking HCM and PH, aiming to lay the groundwork for targeted therapeutic interventions. Methods: Through the analysis of gene expression profiles from datasets GSE36961 (HCM) and GSE113439 (PH) within the public data repository of Gene Expression Omnibus (GEO), this research systematically identified differentially expressed genes (DEGs), conducted extensive functional annotations, and constructed detailed protein-protein interaction (PPI) networks to uncover crucial hub genes. Further, co-expression analyses, alongside drug prediction and molecular docking simulations, were employed to pinpoint potential therapeutic agents that could ameliorate the combined pathology of HCM and PH. Results: Our comprehensive analysis unearthed 79 DEGs shared between HCM and PH, highlighting fourteen as pivotal hub genes. Validation across three additional datasets (GSE35229, GSE32453, and GSE53408) from GEO accentuated secreted phosphoprotein 1 (SPP1) as a key gene of interest. Remarkably, the study identified tacrolimus, ponatinib, bosutinib, dasatinib, doxorubicin, and zanubrutinib as promising drugs for addressing the dual challenge of HCM and PH. Conclusions: The findings of this investigation shed light on the genetic underpinnings of HCM and PH's simultaneous occurrence, emphasizing the central role of SPP1 in their pathogenesis. The identification of six candidate drugs offers a hopeful vista for future therapeutic strategies targeting this complex cardiovascular interplay, marking a significant stride towards mitigating the compounded morbidity of HCM and PH. Future mechanistic and clinical studies are warranted for the investigation of this potential target and therapeutics.
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Protein-fragment complementation assays (PCAs) are powerful tools to investigate protein-protein interactions in a cellular context. These are especially useful to study unstable proteins and weak interactions that may not resist protein isolation or purification. The PCA based on the reconstitution of the Gaussia princeps luciferase (split-luc) is a sensitive approach allowing the mapping of protein-protein interactions and the semiquantitative measurement of binding affinity. Here, we describe the split-luc protocol we used to map the viral interactome of measles virus polymerase complex.
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Vírus do Sarampo , Ligação Proteica , Mapeamento de Interação de Proteínas , Mapeamento de Interação de Proteínas/métodos , Humanos , Luciferases/metabolismo , Luciferases/genética , Proteínas Virais/metabolismo , RNA Polimerase Dependente de RNA/metabolismoRESUMO
In a recent study, we have identified BPH03 as a promising scaffold for the development of compounds aimed at modulating the interaction between PED/PEA15 (Phosphoprotein Enriched in Diabetes/Phosphoprotein Enriched in Astrocytes 15) and PLD1 (phospholipase D1), with potential applications in type II diabetes therapy. PED/PEA15 is known to be overexpressed in certain forms of diabetes, where it binds to PLD1, thereby reducing insulin-stimulated glucose transport. The inhibition of this interaction reestablishes basal glucose transport, indicating PED as a potential target of ligands capable to recover glucose tolerance and insulin sensitivity. In this study, we employ computational methods to provide a detailed description of BPH03 interaction with PED, evidencing the presence of a hidden druggable pocket within its PLD1 binding surface. We also elucidate the conformational changes that occur during PED interaction with BPH03. Moreover, we report new NMR data supporting the in-silico findings and indicating that BPH03 disrupts the PED/PLD1 interface displacing PLD1 from its interaction with PED. Our study represents a significant advancement toward the development of potential therapeutics for the treatment of type II diabetes.
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Idiopathic pulmonary fibrosis (IPF) is a chronic and progressive disease with high mortality rates. It has been shown that pirfenidone (PFD) and nintedanib (Ofev) can slow down the decline in lung function of IPF patients, but their efficacy remains suboptimal. Some studies have suggested that the combination of PFD and Ofev may yield promising results. However, there is a lack of research on the combined application of these two medications in the treatment of IPF. A mouse model of bleomycin-induced (BLM) pulmonary fibrosis was established to investigate the impact of combination therapy on pulmonary fibrosis of mice. The findings demonstrated a significant reduction in lung tissue damage in mice treated with the combination therapy. Subsequent transcriptome analysis identified the differential gene secreted phosphoprotein 1 (SPP1), which was found to be associated with macrophages and fibroblasts based on multiple immunofluorescence staining results. Analysis of a phosphorylated protein microarray indicated that SPP1 plays a regulatory role in macrophages and fibroblasts via the AKT pathway. Consequently, the regulation of macrophages and fibroblasts in pulmonary fibrosis by the combination of PFD and Ofev is mediated by SPP1 through the AKT pathway, potentially offering a novel therapeutic option for IPF patients. Further investigation into the targeting of SPP1 for the treatment of pulmonary fibrosis is warranted.
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Fibroblastos , Indóis , Macrófagos , Camundongos Endogâmicos C57BL , Osteopontina , Proteínas Proto-Oncogênicas c-akt , Piridonas , Animais , Camundongos , Antifibróticos/farmacologia , Antifibróticos/uso terapêutico , Bleomicina , Quimioterapia Combinada , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibroblastos/patologia , Fibrose Pulmonar Idiopática/tratamento farmacológico , Fibrose Pulmonar Idiopática/metabolismo , Fibrose Pulmonar Idiopática/patologia , Fibrose Pulmonar Idiopática/induzido quimicamente , Indóis/farmacologia , Indóis/uso terapêutico , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Osteopontina/efeitos dos fármacos , Osteopontina/metabolismo , Proteínas Proto-Oncogênicas c-akt/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Piridonas/farmacologia , Piridonas/uso terapêutico , Transdução de Sinais/efeitos dos fármacosRESUMO
Rabies virus (RABV) is highly lethal and triggers severe neurological symptoms. The neuropathogenic mechanism remains poorly understood. Ras-related C3 botulinum toxin substrate 1 (Rac1) is a Rho-GTPase that is involved in actin remodeling and has been reported to be closely associated with neuronal dysfunction. In this study, by means of a combination of pharmacological inhibitors, small interfering RNA, and specific dominant-negatives, we characterize the crucial roles of dynamic actin and the regulatory function of Rac1 in RABV infection, dominantly in the viral entry phase. The data show that the RABV phosphoprotein interacts with Rac1. RABV phosphoprotein suppress Rac1 activity and impedes downstream Pak1-Limk1-Cofilin1 signaling, leading to the disruption of F-actin-based structure formation. In early viral infection, the EGFR-Rac1-signaling pathway undergoes a biphasic change, which is first upregulated and subsequently downregulated, corresponding to the RABV entry-induced remodeling pattern of F-actin. Taken together, our findings demonstrate for the first time the role played by the Rac1 signaling pathway in RABV infection and may provide a clue for an explanation for the etiology of rabies neurological pathogenesis.IMPORTANCEThough neuronal dysfunction is predominant in fatal rabies, the detailed mechanism by which rabies virus (RABV) infection causes neurological symptoms remains in question. The actin cytoskeleton is involved in numerous viruses infection and plays a crucial role in maintaining neurological function. The cytoskeletal disruption is closely associated with abnormal nervous symptoms and induces neurogenic diseases. In this study, we show that RABV infection led to the rearrangement of the cytoskeleton as well as the biphasic kinetics of the Rac1 signal transduction. These results help elucidate the mechanism that causes the aberrant neuronal processes by RABV infection and may shed light on therapeutic development aimed at ameliorating neurological disorders.
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Citoesqueleto de Actina , Actinas , Vírus da Raiva , Transdução de Sinais , Proteínas rac1 de Ligação ao GTP , Proteínas rac1 de Ligação ao GTP/metabolismo , Proteínas rac1 de Ligação ao GTP/genética , Humanos , Citoesqueleto de Actina/metabolismo , Animais , Vírus da Raiva/fisiologia , Actinas/metabolismo , Receptores ErbB/metabolismo , Receptores ErbB/genética , Quinases Ativadas por p21/metabolismo , Quinases Ativadas por p21/genética , Quinases Lim/metabolismo , Quinases Lim/genética , Internalização do Vírus , Raiva/metabolismo , Raiva/virologia , Linhagem Celular , Fosfoproteínas/metabolismo , Fosfoproteínas/genética , Fatores de Despolimerização de Actina/metabolismoRESUMO
This study evaluated the safety, tolerability, pharmacokinetics, and pharmacodynamics of BI 685509 after oral single rising doses (SRDs) or multiple rising doses (MRDs) in healthy volunteers. In the SRD trial (NCT02694354; February 29, 2016), within each of the three dose groups (DGs), six subjects received BI 685509 (1.0, 2.5, or 5.0 mg) and two received placebo (N = 24). In the MRD trial (NCT03116906; April 17, 2017), within each of the five DGs, nine subjects received BI 685509 (uptitrated to 1 mg once daily [qd; DG1], 2.5 mg twice daily [DG2], 5.0 mg qd [DG3]; 3.0 mg three times daily [tid; DG4] or 4.0 mg tid [DG5]) and three received placebo, for 14-17 days (N = 60). In the SRD trial, 7/24 subjects (29.2%) had ≥ 1 adverse event (AE), most frequently orthostatic dysregulation (n = 4). In the MRD trial, 26/45 subjects (57.8%) receiving BI 685509 had ≥ 1 AE, most frequently orthostatic dysregulation and fatigue (each n = 12). Tolerance development led to a marked decrease in orthostatic dysregulation events (DG3). BI 685509 was rapidly absorbed after oral administration, and exposure increased in a dose-proportional manner after single doses. Multiple dosing resulted in near-dose-proportional increase in exposure and limited accumulation. BI 685509 pharmacokinetics appeared linear with time; steady state occurred 3-5 days after each multiple-dosing period. Increased plasma cyclic guanosine monophosphate and decreased blood pressure followed by a compensatory increase in heart rate indicated target engagement. BIâ¯685509 was generally well tolerated; orthostatic dysregulation may be appropriately countered by careful uptitration.
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Hepatocellular carcinoma (HCC) is a fatal digestive system cancer with unclear pathogenesis. M-phase phosphoprotein 8 (MPP8) has been shown to play a vital role in several cancer types, such as non-small cell lung cancer, gastric cancer and melanoma; however, there have been no studies into its role in HCC. The present study aimed to evaluate the role of MPP8 in regulating malignant phenotypes of liver cancer cells, and to further investigate the underlying mechanism. Bioinformatics analysis was performed to analyze related data from a public database, and to predict the potential microRNAs (miRNAs) that might target MPP8 mRNA; reverse transcription-quantitative PCR was used to measure the levels of mRNA and miRNA; western blotting was employed to detect protein levels; Cell Counting Kit-8 (CCK-8) and plate colony formation assays, wound healing assay and Transwell invasion assay were performed to evaluate the ability of cell proliferation, migration and invasion, respectively; dual-luciferase reporter gene assay was performed to identify the target association. The results showed that MPP8 was a risk factor for the survival of patients with HCC, and was up-regulated in HCC tissue samples and cell lines; MPP8 knockdown inhibited the proliferation, migration and invasion of liver cancer cells; MPP8 knockdown suppressed the PI3K/Akt pathway, and activation of this pathway reversed the inhibited liver cancer cell phenotypes by down-regulating MPP8; miR-576-3p, which was low in liver cancer cells, negatively regulated MPP8 expression by directly targeting its mRNA; up-regulating MPP8 expression reversed the inhibited signaling pathway and malignant phenotypes of liver cancer cells by miR-576-3p overexpression. In conclusion, the miR-576-3p/MPP8 axis regulates the proliferation, migration, and invasion of liver cancer cells through the PI3K/Akt signaling pathway. These findings lead novel insights into HCC progression, and propose MPP8 as a potential therapeutic target for HCC.