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31.
Alopecia areata (AA) is an inflammatory hair loss disorder with a major genetic component, which may cause great psychosocial distress for those affected. Studies have shown that interleukin-1 (IL-1) is a very potent inducer of hair loss and a significant human hair growth inhibitor. The 4-bp insertion/deletion (Indel) polymorphism (rs3783553) within the 3′ untranslated regions of IL1A gene has been suggested to be associated with risk of various types of cancers, possibly through regulating expression of IL-1α levels. In the current study, we estimated the susceptibility to AA associated with rs3783553 in two independent case–control panels of Eastern and Southern Chinese populations, totally containing 313 AA cases and 626 healthy controls. Logistic regression analysis showed that the heterozygote and the homozygote 4-bp ins/ins confer a significantly lower risk of AA in both panels and total subjects [odds ratio (OR) = 0.55, 95% confidence interval (C.I.) = 0.41–0.75, P = 6.24 × 10− 5; OR = 0.47, 95% C.I. = 0.28–0.76, P = 0.001, respectively]. Stratification analysis based on age onset showed that the protective roles of ins/del and ins/ins genotype against developing AA was more obvious in AA patients with early age onset (< 30 years) under dominant model (OR = 0.48, 95% C.I. = 0.29–0.77, P = 0.001). The results of luciferase assay showed that rs3783553 could influence expression of IL-1α in a miR-122 dependant manner. Taken together, our results suggested that the IL1A 4-bp indel polymorphism may be a marker for genetic susceptibility to patchy (mild) AA in Chinese populations, likely through miR-122 mediated regulation.  相似文献   
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Polymorphisms of butyrylcholinesterase (BChE) have been reported to be associated to weight, BMI variance and hypertriglyceridemia in adults and adolescents. The aim of the present study was to investigate the association of −116A (SNP: G/A; rs1126680) and 1914G (SNP: A/G; rs3495) variants of BCHE gene with anthropometric and biochemical variables associated with obesity in population sample of 115 individuals, from Southern Brazil. Participants were grouped in two categories: obese (BMI ≥ 30) and non-obese (BMI < 30). The 1914G allele showed significantly higher frequency in the obese group, and carriers of 1914G allele showed lower mean BChE activity when compared to 1914A carriers (p = 0.006). Higher means of BMI (p = 0.02) and triglyceride (TG; p = 0.01) were found in 1914G carriers (BMI = 27.57kg/m2; TG = 150.8 mg/dL) when compared to 1914A homozygotes (BMI = 25.55 kg/m2; TG = 107.9 mg/dL). Carriers of the −116A allele showed lower mean BChE activity than usual homozygotes, and the −116A variant was found in cis with 1914G (p < 0.0001; D′ = 1). The region of BCHE gene that contains the 1914G mutation site is target of microRNAs (miRs) and the response of BChE to glucocorticoids is especially influenced by these miRs. Therefore, it is possible that the 1914G allele can be interfering in gluconeogenesis, hyperglycemia, lipolysis and body fat distribution. This lower activity may cause an imbalance in lipid metabolism, which may lead to an increased predisposition to obesity and to a lower ability to maintain metabolic homeostasis.  相似文献   
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Gene therapy has converged with bone engineering over the past decade, by which a variety of therapeutic genes have been delivered to stimulate bone repair. These genes can be administered via in vivo or ex vivo approach using either viral or nonviral vectors. This article reviews the fundamental aspects and recent progresses in the gene therapy-based bone engineering, with emphasis on the new genes, viral vectors and gene delivery approaches.  相似文献   
34.
The c-Myc oncogene is amplified in many tumor types. It is an important regulator of cell proliferation and has been linked to altered miRNA expression, suggesting that c-Myc-regulated miRNAs might contribute to tumor progression. Although miR-26a has been reported to be upregulated in glioblastoma multiforme (GBM), the mechanism has not been established. We have shown that ectopic expression of miR-26a influenced cell proliferation by targeting PTEN, a tumor suppressor gene that is inactivated in many common malignancies, including GBM. Our findings suggest that c-Myc modulates genes associated with oncogenesis in GBM through deregulation of miRNAs via the c-Myc–miR-26a–PTEN signaling pathway. This may be of clinical relevance.  相似文献   
35.
Although many researches have been undertaken to disclose the mechanisms of chemoresistance, the mechanisms remain unclear. The aim of this study is to elucidate the role of miR-181a–Twist1 pathway in the chemoresistance of tongue squamous cell carcinoma (TSCC). We found that cisplatin-induced chemoresistance in TSCC cell lines underwent EMT (epithelial–mesenchymal transition) and was accompanied by enhancing metastatic potential (migration and invasion in vitro), miR-181a downregulation and Twist1 upregulation. Functional analyses indicated that miR-181a reversed chemoresistance, inhibited EMT and metastatic potential in TSCC cells. Twist1 was confirmed as a direct miR-181a target gene by luciferase reporter gene assays. Twist1 knockdown by siRNA led to a reversal of the chemoresistance, inhibited EMT and metastatic potential in TSCC cells. Our study demonstrates that miR-181a–Twist1 pathway may play an important role in the development of cisplatin-chemoresistance, with EMT and an increase the metastatic potential of TSCC cells.  相似文献   
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In our previous study, miR-126 was identified as one of the leading miRNAs that is downregulated during activation of hepatic stellate cells (HSCs). However, the roles and related mechanisms of miR-126 in HSCs are not understood. In this study, we compared expression of miR-126 during HSC activation both in vitro and in vivo. We also applied RNA interference to analyze the role and mechanism of miR-126 in the activation of HSCs. Restoring HSCs with Lv-miR-126 resulted in decreased proliferation, accumulation of extracellular matrix components, and cell contraction, while also negatively regulating the vascular endothelial growth factor (VEGF) signal transduction pathways by partially targeted VEGF-A. Thus, we postulate that miR-126 may be a biological marker for the activation of HSCs, and useful for reducing intrahepatic vascular resistance and improving the sinusoidal microcirculation in chronic liver diseases.  相似文献   
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Autophagy (macroautophagy) is an evolutionarily conserved lysosomal degradation process, in which a cell degrades long-lived proteins and damaged organelles. Recently, accumulating evidence has revealed the core molecular machinery of autophagy in carcinogenesis; however, the intricate relationship between autophagy and cancer continue to remain an enigma. Why does autophagy have either pro-survival (oncogenic) or pro-death (tumor suppressive) role at different cancer stages, including cancer stem cell, initiation and progression, invasion and metastasis, as well as dormancy? How does autophagy modulate a series of oncogenic and/or tumor suppressive pathways, implicated in microRNA (miRNA) involvement? Whether would targeting the oncogenic and tumor suppressive autophagic network be a novel strategy for drug discovery? To address these problems, we focus on summarizing the dynamic oncogenic and tumor suppressive roles of autophagy and their relevant small-molecule drugs, which would provide a new clue to elucidate the oncosuppressive (survival or death) autophagic network as a potential therapeutic target.  相似文献   
40.
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