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991.
Immune thrombocytopenia (ITP) is a common autoimmune bleeding disorder. The breakdown of immune tolerance (regulatory T [Treg] cells and suppressor cytokines) plays an important role in ITP pathophysiology, especially in refractory ITP. Bone marrow–derived mesenchymal stem cells (BM-MSCs) show immunomodulatory properties and have been extensively utilized for autoimmune diseases. However, it has not been fully elucidated how BM-MSCs affect ITP. In this study, we explore the therapeutic mechanism of BM-MSCs on ITP in mice. Dose-escalation passive ITP mice were inducted by injection of MWReg30. BALB/c mice were randomly divided into two groups: ITP with BM-MSC transplantation and ITP controls. The serum levels of cytokines (interleukin 10 [IL-10] and transforming growth factor-β1 [TGF-β1]) were examined by enzyme-linked immunosorbent assays. The frequency of Treg cells in both peripheral blood and spleen mononuclear cells was analyzed by flow cytometry, and the forkhead box P3 (Foxp3) messenger RNA (mRNA) level was measured by real-time polymerase chain reaction. After BM-MSC treatment, the platelet (PLT) counts were significantly elevated. Meanwhile, cytokines (TGF-β1 and IL-10), the ratios of Treg cells, and the Foxp3 mRNA expression level were significantly higher in the BM-MSC group. Our results show that BM-MSCs can improve PLT counts mainly by secreting suppressive cytokines and upregulating Tregs, which may provide new therapeutic potential for human ITP.  相似文献   
992.
The purpose of this study was to evaluate the effects of three toxic β‐glucosides, phlorizin, santonin, and amygdalin, on carbohydrate metabolism in the cotton bollworm, Helicoverpa armigera (Hübner), when diets mixed with β‐glucosides were fed to third‐instar larvae. The growth of the larvae was significantly inhibited by exposure to santonin after 96 hr but not obviously affected by phlorizin and amygdalin. The midgut trehalase activities were only 51.7%, 32%, and 42.5% of that of the control after treatment with phlorizin, santonin and amygdalin at 2 mg/ml, respectively. In the hemolymph and fat body, the amount of trehalose decreased in all cases. However, the effects of santonin on the alteration of the glycogen and glucose levels as well as the activities of glycogen phosphorylase, were different than those of the other two β‐glucosides. It appears that the three β‐glucosides have different influences on the carbohydrate metabolism of cotton bollworm.  相似文献   
993.
Chemoresistance often causes treatment failure of B-cell acute lymphoblastic leukemia (B-ALL). However, the mechanism remains unclear at present. Herein, overexpression of heme oxygenase-1 (HO-1) was found in the bone marrow stromal cells (BMSCs) from B-ALL patients developing resistance to vincristine (VCR), a chemotherapeutic agent. Two B-ALL cell lines Super B15 and CCRF-SB were cocultured with BMSCs transfected with lentivirus to regulate the expression of HO-1. Silencing HO-1 expression in BMSCs increased the apoptotic rates of B-ALL cell lines induced by VCR, whereas upregulating HO-1 expression reduced the rate. Cell cycle can be arrested in the G2/M phase by VCR. In contrast, B-ALL cells were arrested in the G0/G1 phase due to HO-1 overexpression in BMSCs, which avoided damage from the G2/M phase. Vascular endothelial growth factor (VEGF) in BMSCs, as a key factor in the microenvironment-associated chemoresistance, was also positively coexpressed with HO-1. VEGF secretion was markedly increased in BMSCs with HO-1 upregulation but decreased in BMSCs with HO-1 silencing. B-ALL cell lines became resistant to VCR when cultured with VEGF recombinant protein, so VEGF secretion induced by HO-1 expression may promote the VCR resistance of B-ALL cells. As to the molecular mechanism, the PI3K/AKT pathway mediated regulation of VEGF by HO-1. In conclusion, this study clarifies a mechanism by which B-ALL is induced to resist VCR through HO-1 overexpression in BMSCs, and provides a novel strategy for overcoming VCR resistance in clinical practice.  相似文献   
994.
995.
Clinical application of oxaliplatin, a platinum-based chemotherapeutic agent, in cancer, especially colorectal cancer, is widely used. However, oxaliplatin-induced peripheral neurotoxicity (OIPN) has a high incidence, and to date, there have been few detailed studies on pathogenesis and treatment mechanisms. The present study was performed by using a proteomic approach to explore protein expression profiling of rats treated with oxaliplatin by multiplex isobaric tags for relative and absolute quantification labeling and two-dimensional liquid chromatography-tandem mass spectrometry. There were 74 proteins that showed different expression in sciatic nerve between control rats and OIPN model rats, with 53 upregulated proteins and 21 downregulated proteins detected in OIPN groups compared with control groups. On the basis of Gene Ontology clustering, these proteins were associated with biological processes (eg, muscle contraction, muscle system process, and skeletal muscle contraction), cellular component (eg, myofibril, contractile fiber, and contractile fiber part) and molecular function (structural constituent of muscle, hydro-lyase activity, and calcium ion binding). On the basis of Kyoto Encyclopedia of Genes and Genomes pathway database, these proteins were associated with African trypanosomiasis, malaria, nitrogen metabolism, etc. Real-time polymerase chain reaction, Western blot as well as immunohistochemistry analysis was performed to examine the expression of partially differential protein. In conclusion, our study establishes a protein expression profile of oxaliplatin-induced rats and mechanisms leading to OIPN development, and will be useful for developing novel diagnostic biomarkers and aiding in the prevention and control of OIPN.  相似文献   
996.
Estrogen-related receptor α (ERRα) belongs to the superfamily of nuclear orphan receptors. However, the role of ERRα in bladder cancer remains unknown. This study examined the expression of ERRα in bladder cancer tissues and explored the molecular mechanisms of ERRα in bladder cancer progression. The expression of ERRα in bladder cancer tissues from 61 patients was determined by immunohistochemistry. We performed quantitative real-time polymerase chain reaction assay to detect the gene expression levels and carried out Western blot assay to measure protein levels. In vitro functional assays, including colony formation, Cell Counting Kit-8, Transwell invasion, and migration assays, were performed to detect bladder cancer cell growth, proliferation, invasion, and migration, respectively. Flow cytometry was used to determine the cell apoptotic rate of bladder cancer cells. Among the 61 detected bladder cancer tissues, 39 bladder cancer tissues showed positive ERRα immunoreactivity. Higher ERRα immunoreactivity score was significantly associated with TNM stage, tumor grade, distant metastasis, and poor survival in patients with bladder cancer. Univariate and multivariate analyses showed that ERRα immunoreactivity was an independent prognostic factor for overall survival in patients with bladder cancer. ERRα was found to be upregulated in bladder cancer cell lines, and knockdown of ERRα suppressed bladder cancer cell growth, proliferation, invasion, and migration; promoted bladder cancer cell apoptosis; and inhibited the epithelial-mesenchymal transition of bladder cancer cells. On the other hand, bladder cancer cell proliferation, invasion, and migration were significantly enhanced after cells were transfected with an ERRα-overexpressing vector. In vivo tumor growth and metastasis assays showed that ERRα knockdown resulted in remarkable inhibition of tumor growth and tumor metastasis in nude mice. Collectively, our results suggest that the enhanced expression of ERRα may play a key role in the development and progression of bladder cancer and ERRα may serve as an important prognostic factor for bladder cancer.  相似文献   
997.
Due to high rates of metastasis and poor clinical outcomes for patients, it is important to study the pathomechanisms of osteosarcoma. However, due to the fact that osteosarcoma shows significant interindividual variation and high heterogeneity, the identification of differentially expressed genes (DEGs) at the population level cannot answer many important questions related to osteosarcoma tumorigenesis. Therefore, a new strategy to identify dysregulated genes in osteosarcoma samples is required. The aim of this study was to improve our understanding of osteosarcoma pathogenesis by identifying genes with universal aberrant expression in osteosarcoma samples. Because the relative expression ordering of genes is stable in normal bone tissues but is disrupted in osteosarcoma tissues, we used the RankComp algorithm to identify DEGs in normal and osteosarcoma tissue samples. We then calculated the dysregulation frequency for each gene. Genes with deregulation frequencies above 80% were deemed to be universal DEGs. Next, coexpression, pathway enrichment, and protein-protein interaction network analyses were performed to characterize the functions of these genes. From 188 samples of osteosarcoma obtained from four datasets measured on different platforms, 51 universal DEGs were identified, including 4 universally upregulated genes and 47 universally downregulated genes. Genes that were differentially coexpressed with these universal DEGs were found to be enriched in 46 cancer-related pathways. In addition, functional and network analyses showed that genes with high dysregulation frequencies were involved in cancer-related functions. Thus, the commonly aberrant genes identified in osteosarcoma tissues may be important targets for osteosarcoma diagnosis and therapy.  相似文献   
998.
Gastric cancer is one of the top causes of cancer-related death around the world, and poor prognosis of gastric cancer is due to the lack of early detection and effective treatment especially in male. Here, we first revealed the role of histone lysine-specific demethylase 5D (KDM5D) in gastric cancer in male. KDM5D was associated with the metastasis of gastric cancer because of its critical role in the epithelial-mesenchymal transition of gastric cancer cells. Downregulation of KDM5D in gastric cancer cells significantly increase the number of migrated or invaded cells due to the increasing expressions of mesenchymal markers. Downregulation of KDM5D also promotes tumor formation of gastric cancer cell in vivo. For mechanism, downregulation of KDM5D could inhibit the demethylation in the promoter of CUL4A, which lead to the increasing expression of ZEB1 and decreasing expressions of p21 and p53. Collectively, KDM5D performed its role in metastasis of gastric cancer through demethylation in the promoter of CUL4A, and it suggested us a novel target in gastric cancer treatment in male.  相似文献   
999.
Deregulated long noncoding RNAs (lncRNA) have been critically implicated in tumorigenesis and serve as novel diagnostic and prognostic biomarkers. Here we sought to develop a prognostic lncRNA signature in patients with head and neck squamous cell carcinoma (HNSCC). Original RNA-seq data of 499 HNSCC samples were retrieved from The Cancer Genome Atlas database, which was randomly divided into training and testing set. Univariate Cox regression survival analysis, robust likelihood-based survival model and random sampling iterations were applied to identify prognostic lncRNA candidates in the training cohort. A prognostic risk score was developed based on the Cox coefficient of four individual lncRNA imputed as follows: (0.14546 × expression level of RP11-366H4.1) + (0.27106 × expression level of LINC01123) + (0.54316 × expression level of RP11-110I1.14) + (−0.48794 × expression level of CTD-2506J14.1). Kaplan-Meier analysis revealed that patients with high-risk score had significantly reduced overall survival as compared with those with low-risk score when patients in training, testing, and validation cohorts were stratified into high- or low-risk subgroups. Multivariate survival analysis further revealed that this 4-lncRNA signature was a novel and important prognostic factor independent of multiple clinicopathological parameters. Importantly, ROC analyses indicated that predictive accuracy and sensitivity of this 4-lncRNA signature outperformed those previously well-established prognostic factors. Noticeably, prognostic score based on quantification of these 4-lncRNA via qRT-PCR in another independent HNSCC cohort robustly stratified patients into subgroups with high or low survival. Taken together, we developed a robust 4-lncRNA prognostic signature for HNSCC that might provide a novel powerful prognostic biomarker for precision oncology.  相似文献   
1000.
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