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261.
Glioblastoma (GBM) is a malignant intracranial tumour with the highest proportion and lethality. It is characterized by invasiveness and heterogeneity. However, the currently available therapies are not curative. As an essential environmental cue that maintains glioma stem cells, hypoxia is considered the cause of tumour resistance to chemotherapy and radiation. Growing evidence shows that immunotherapy focusing on the tumour microenvironment is an effective treatment for GBM; however, the current clinicopathological features cannot predict the response to immunotherapy and provide accurate guidance for immunotherapy. Based on the ESTIMATE algorithm, GBM cases of The Cancer Genome Atlas (TCGA) data set were classified into high‐ and low‐immune/stromal score groups, and a four‐gene tumour environment‐related model was constructed. This model exhibited good efficiency at forecasting short‐ and long‐term prognosis and could also act as an independent prognostic biomarker. Additionally, this model and four of its genes (CLECL5A, SERPING1, CHI3L1 and C1R) were found to be associated with immune cell infiltration, and further study demonstrated that these four genes might drive the hypoxic phenotype of perinecrotic GBM, which affects hypoxia‐induced glioma stemness. Therefore, these might be important candidates for immunotherapy of GBM and deserve further exploration.  相似文献   
262.
263.
Chronic pancreatitis (CP), characterized by pancreatic fibrosis, is a recurrent, progressive and irreversible disease. Activation of the pancreatic stellate cells (PSCs) is considered a core event in pancreatic fibrosis. In this study, we investigated the role of hydrogen peroxide‐inducible clone‐5 (Hic‐5) in CP. Analysis of the human pancreatic tissue samples revealed that Hic‐5 was overexpressed in patients with CP and was extremely low in healthy pancreas. Hic‐5 was significant up‐regulated in the activated primary PSCs independently from transforming growth factor beta stimulation. CP induced by cerulein injection was ameliorated in Hic‐5 knockout (KO) mice, as shown by staining of tissue level. Simultaneously, the activation ability of the primary PSCs from Hic‐5 KO mice was significantly attenuated. We also found that the Hic‐5 up‐regulation by cerulein activated the NF‐κB (p65)/IL‐6 signalling pathway and regulated the downstream extracellular matrix (ECM) genes such as α‐SMA and Col1a1. Therefore, we determined whether suppressing NF‐κB/p65 alleviated CP by treating mice with the NF‐κB/p65 inhibitor triptolide in the cerulein‐induced CP model and found that pancreatic fibrosis was alleviated by NF‐κB/p65 inhibition. These findings provide evidence for Hic‐5 as a therapeutic target that plays a crucial role in regulating PSCs activation and pancreatic fibrosis.  相似文献   
264.
Benign prostatic hyperplasia (BPH) occurs most commonly among older men, often accompanied by chronic tissue inflammation. Although its aetiology remains unclear, autoimmune dysregulation may contribute to BPH. Regulatory T cells (Tregs) prevent autoimmune responses and maintain immune homeostasis. In this study, we aimed to investigate Tregs frequency, phenotype, and function in BPH patients and to evaluate adoptive transfer Tregs for immunotherapy in mice with BPH via CD39. Prostate specimens and peripheral blood from BPH patients were used to investigate Treg subsets, phenotype and Treg‐associated cytokine production. Sorted CD39+/? Tregs from healthy mice were adoptively transferred into mice before or after testosterone propionate administration. The Tregs percentage in peripheral blood from BPH patients was attenuated, exhibiting low Foxp3 and CD39 expression with low levels of serum IL‐10, IL‐35 and TGF‐β. Immunohistochemistry revealed Foxp3+ cells were significantly diminished in BPH prostate with severe inflammatory. Although the Tregs subset was comprised of more effector/memory Tregs, CD39 was still down‐regulated on effector/memory Tregs in BPH patients. Before or after testosterone propionate administration, no alterations of BPH symptoms were observed due to CD39‐ Tregs in mice, however, CD39+Tregs existed more potency than Tregs to regulate prostatic hyperplasia and inhibit inflammation by decreasing IL‐1β and PSA secretion, and increasing IL‐10 and TGF‐β secretion. Furthermore, adoptive transfer with functional Tregs not only improved prostate hyperplasia but also regulated muscle cell proliferation in bladder. Adoptive transfer with Tregs may provide a novel method for the prevention and treatment of BPH clinically.  相似文献   
265.
Breast cancer is the most frequently diagnosed cancer and the leading cause of cancer‐related deaths in women worldwide. In this study, a large Chinese pedigree with breast cancer including a proband and two female patients was recruited and a familial history of breast cancer was collected by questionnaire. Clinicopathological assessments and neoadjuvant therapy‐related information were obtained for the proband. Blood samples were taken, and gDNA was extracted. The BRCA1/2 and PALB2 genes were screened using next‐generation sequencing by a targeted gene panel. We have successfully identified a novel, germline heterozygous, missense mutation of the gene BRCA2: c.7007G>T, p.R2336L, which is likely to be pathogenic in the proband and her elder sister who both had breast cancer. Furthermore, the risk factors for developing breast cancer in this family are discussed. Thus, genetic counselling and long‐term follow‐up should be provided for this family of breast cancer patients as well as carriers carrying a germline variant of BRCA2: c.7007G>T (p.R2336L).  相似文献   
266.
Amyotrophic lateral sclerosis (ALS) is a disorder that affects motor neurons in motor cortex and spinal cord, and the degeneration of both neuronal populations is a critical feature of the disease. Abnormalities in protein homeostasis (proteostasis) are well established in ALS. However, they have been investigated mostly in spinal cord but less so in motor cortex. Herein, we monitored the unfolded protein (UPR) and heat shock response (HSR), two major proteostasis regulatory pathways, in human post-mortem tissue derived from the motor cortex of sporadic ALS (SALS) and compared them to those occurring in spinal cord. Although the UPR was activated in both tissues, specific expression of select UPR target genes, such as PDIs, was observed in motor cortex of SALS cases strongly correlating with oligodendrocyte markers. Moreover, we found that endoplasmic reticulum-associated degradation (ERAD) and HSR genes, which were activated predominately in spinal cord, correlated with the expression of neuronal markers. Our results indicate that proteostasis is strongly and selectively activated in SALS motor cortex and spinal cord where subsets of these genes are associated with specific cell type. This study expands our understanding of convergent molecular mechanisms occurring in motor cortex and spinal cord and highlights cell type–specific contributions.  相似文献   
267.
Evidence demonstrates that M1 macrophage polarization promotes inflammatory disease. Here, we discovered that (R)‐salbutamol, a β2 receptor agonist, inhibits and reprograms the cellular metabolism of RAW264.7 macrophages. (R)‐salbutamol significantly inhibited LPS‐induced M1 macrophage polarization and downregulated expressions of typical M1 macrophage cytokines, including monocyte chemotactic protein‐1 (MCP‐1), interleukin‐1β (IL‐1β) and tumour necrosis factor α (TNF‐α). Also, (R)‐salbutamol significantly decreased the production of inducible nitric oxide synthase (iNOS), nitric oxide (NO) and reactive oxygen species (ROS), while increasing the reduced glutathione (GSH)/oxidized glutathione (GSSG) ratio. In contrast, (S)‐salbutamol increased the production of NO and ROS. Bioenergetic profiles showed that (R)‐salbutamol significantly reduced aerobic glycolysis and enhanced mitochondrial respiration. Untargeted metabolomics analysis demonstrated that (R)‐salbutamol modulated metabolic pathways, of which three metabolic pathways, namely, (a) phenylalanine metabolism, (b) the pentose phosphate pathway and (c) glycerophospholipid metabolism were the most noticeably impacted pathways. The effects of (R)‐salbutamol on M1 polarization were inhibited by a specific β2 receptor antagonist, ICI‐118551. These findings demonstrated that (R)‐salbutamol inhibits the M1 phenotype by downregulating aerobic glycolysis and glycerophospholipid metabolism, which may propose (R)‐salbutamol as the major pharmacologically active component of racemic salbutamol for the treatment of inflammatory diseases and highlight the medicinal value of (R)‐salbutamol.  相似文献   
268.
A growing number of studies recognize that long non‐coding RNAs (lncRNAs) are essential to mediate multiple tumorigenic processes, including hepatic tumorigenesis. However, the pathological mechanism of lncRNA‐regulated liver cancer cell growth remains poorly understood. In this study, we identified a novel function lncRNA, named polo‐like kinase 4 associated lncRNA (lncRNA PLK4, GenBank Accession No. RP11‐50D9.3), whose expression was dramatically down‐regulated in hepatocellular carcinoma (HCC) tissues and cells. Interestingly, talazoparib, a novel and highly potent poly‐ADP‐ribose polymerase 1/2 (PARP1/2) inhibitor, could increase lncRNA PLK4 expression in HepG2 cells. Importantly, we showed that talazoparib‐induced lncRNA PLK4 could function as a tumour suppressor gene by Yes‐associated protein (YAP) inactivation and induction of cellular senescence to inhibit liver cancer cell viability and growth. In summary, our findings reveal the molecular mechanism of talazoparib‐induced anti‐tumor effect, and suggest a potential clinical use of talazoparib‐targeted lncRNA PLK4/YAP‐dependent cellular senescence for the treatment of HCC.  相似文献   
269.
Cardiovascular complications are leading causes of morbidity and mortality in patients with chronic kidney disease (CKD). CKD significantly affects cardiac calcium (Ca2+) regulation, but the underlying mechanisms are not clear. The present study investigated the modulation of Ca2+ homeostasis in CKD mice. Echocardiography revealed impaired fractional shortening (FS) and stroke volume (SV) in CKD mice. Electrocardiography showed that CKD mice exhibited longer QT interval, corrected QT (QTc) prolongation, faster spontaneous activities, shorter action potential duration (APD) and increased ventricle arrhythmogenesis, and ranolazine (10 µmol/L) blocked these effects. Conventional microelectrodes and the Fluo-3 fluorometric ratio techniques indicated that CKD ventricular cardiomyocytes exhibited higher Ca2+ decay time, Ca2+ sparks, and Ca2+ leakage but lower [Ca2+]i transients and sarcoplasmic reticulum Ca2+ contents. The CaMKII inhibitor KN93 and ranolazine (RAN; late sodium current inhibitor) reversed the deterioration in Ca2+ handling. Western blots revealed that CKD ventricles exhibited higher phosphorylated RyR2 and CaMKII and reduced phosphorylated SERCA2 and SERCA2 and the ratio of PLB-Thr17 to PLB. In conclusions, the modulation of CaMKII, PLB and late Na+ current in CKD significantly altered cardiac Ca2+ regulation and electrophysiological characteristics. These findings may apply on future clinical therapies.  相似文献   
270.
Natural products were extracted from traditional Chinese herbal emerging as potential therapeutic drugs for treating cardiovascular diseases. This study examines the role and underlying mechanism of dihydromyricetin (DMY), a natural compound extracted from Ampelopsis grossedentata, in atherosclerosis. DMY treatment significantly inhibits atherosclerotic lesion formation, proinflammatory gene expression and the influx of lesional macrophages and CD4-positive T cells in the vessel wall and hepatic inflammation, whereas increases nitric oxide (NO) production and improves lipid metabolism in apolipoprotein E-deficient (Apoe/) mice. Yet, those protective effects are abrogated by using NOS inhibitor L-NAME in Apoe/ mice received DMY. Mechanistically, DMY decreases microRNA-21 (miR-21) and increases its target gene dimethylarginine dimethylaminohydrolase-1 (DDAH1) expression, an effect that reduces asymmetric aimethlarginine (ADMA) levels, and increases endothelial NO synthase (eNOS) phosphorylation and NO production in cultured HUVECs, vascular endothelium of atherosclerotic lesions and liver. In contrast, systemic delivery of miR-21 in Apoe/ mice or miR-21 overexpression in cultured HUVECs abrogates those DMY-mediated protective effects. These data demonstrate that endothelial miR-21-inhibited DDAH1-ADMA-eNOS-NO pathway promotes the pathogenesis of atherosclerosis which can be rescued by DMY. Thus, DMY may represent a potential therapeutic adjuvant in atherosclerosis management.  相似文献   
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