内皮祖细胞来源外泌体在体外循环致脑损伤中作用研究

目的 探讨内皮祖细胞来源的外泌体在体外循环引起的脑损伤中的作用机制.方法 选取雄性SD大鼠45只,随机分为假手术组、体外循环组与外泌体处理组,每组15只.假手术组大鼠采用气管插管机械通气,仅在右股动脉、右颈内静脉穿刺置管;体外循环组建立无血预充非停跳体外循环术后认知功能障碍模型;外泌体处理组大鼠动物模型同体外循环组,待...     

The role of exosomes in metastasis and progression of melanoma

The mechanisms of melanoma metastasis have been the subject of extensive research for decades. Improved diagnostic and therapeutic strategies are of increasing importance for the treatment of melanoma due to its high burden of mortality in the advanced stages of the disease. Intercellular communication is a critical event for the progression of cancer. Collective evidence suggests that exosomes, small extracellular membrane vesicles released by the cells, are important facilitators of intercellular communication between the cells and the surrounding environment. Although the emerging field of exosomes is rapidly gaining traction in the scientific community, there is limited knowledge regarding the role of exosomes in melanoma. This review discusses the multifaceted role of melanoma-derived exosomes in promoting the process of metastasis by modulating the invasive and angiogenic capacity of malignant cells. The future implications of exosome research and the therapeutic potential of exosomes are also discussed.     

exosome的研究进展

exosome是一种可由多种细胞分泌的纳米量级的膜性小囊泡。经研究后发现,其内含有独特的蛋白质与脂质。这也决定了exosome的生物学功用,如去除细胞生长过程中的废弃蛋白、抗原提呈、信号传导或诱导抗肿瘤免疫反应等。本文就exosome的研究进展做一综述,阐述到目前为止对exosome的生理组成及生物功能的研究成果,并探讨其在生物学应用方面的潜在前景。     

Exosomes in ascites from patients with human pancreatic cancer enhance remote metastasis partially through endothelial-mesenchymal transition

BackgroundDespite advances in multidisciplinary treatment, the prognosis of pancreatic cancer remains poor. Since distant metastasis defines prognosis, elucidation of the mechanism of metastasis is important for improving survival. Exosomes are extracellular secretory vesicles and are responsible for intercellular communication. In this study, we investigated whether exosomes secreted by human pancreatic cancer cells are involved in promoting distant metastasis of cancer and the mechanism that underlies the promotion of metastasis.MethodsExosomes were isolated from ascites of a patient with pancreatic cancer and a patient with liver cirrhosis as a control. Three days after the administration of exosomes to nude mice, GFP-labeled human pancreatic cancer cells were injected via the spleen or tail vein, and then the liver and lungs were histologically analyzed. To elucidate the mechanism, vascular permeability was estimated using FITC-dextran in place of pancreatic cancer cells in vivo and human umbilical vascular endothelial cells (HUVECs) were used to analyze vascular permeability and the induction of endothelial-mesenchymal transition (EndMT) in vitro.ResultsDistant metastasis and vascular permeability were significantly enhanced in mice treated with exosomes from pancreatic cancer patients in comparison to exosomes from a control patient in vivo. In addition, exosomes from pancreatic cancer patients significantly enhanced vascular permeability and the induction of EndMT in HUVECs in vitro.ConclusionExosomes derived from pancreatic cancer cells form a pre-metastatic niche and promote the extravasation and colonization of pancreatic cancer cells to remote organs, partially through endothelial-mesenchymal transition.     

肿瘤相关成纤维细胞外泌体miRNA-656-3p调控喉癌生长侵袭及丹参酮ⅡA对其调控研究

目的研究喉癌肿瘤相关成纤维细胞(CAFs)外泌体表达下调的miRNA-656-3p对喉癌细胞生长和侵袭能力的影响以及丹参酮ⅡA对其调控作用。方法将CAFs外泌体miRNA-656-3p表达上调,制备外泌体上清,检测其对喉癌细胞体外增殖、侵袭能力及细胞周期的影响。检测中药提取物丹参酮ⅡA是否具有类似的上调CAFs外泌体miRNA-656-3p表达的作用,其作用后的CAFs外泌体上清是否具有类似的抑制喉癌增殖和侵袭能力的功效。结果过表达miR-656-3p的CAFs外泌体上清能抑制喉癌细胞的体外增殖和侵袭能力,抑制CCND2的表达,并将喉癌细胞阻滞在G0/G1期。而丹参酮ⅡA也可以上调CAFs外泌体中miR-656-3p的表达水平,其作用后的CAFs外泌体能发挥类似的抑制喉癌细胞体外增殖和侵袭的功效。结论喉癌CAFs外泌体miRNA-656-3p的表达下调促进喉癌细胞的生长和侵袭能力,丹参酮ⅡA可上调CAFs外泌体miR-656-3p的表达,通过后者抑制喉癌细胞的生长和侵袭能力。     

CircRNA在胃癌液体活检中的研究进展

胃癌因其高流行状态已成为我国一大公共卫生问题。环状RNA（circRNA）由于可稳定存在于人类的多种体液中,具备液态活检的先天优势,成为近年来精准治疗领域的研究热点。本文通过检索PubMed、Web of Science、中国知网等数据库文献,基于circRNA的生物学特征,归纳circRNA在胃癌早期筛查诊断、疗效监测、预后评估等方面的研究进展,论述circRNA作为新兴液体活检标志物的可能性及可靠性,为今后circRNA作为胃癌临床诊疗、评估、预后分子标志物的开发和转化提供思路。     

外泌体在缺血性脑卒中的研究进展

正1外泌体概述外泌体是直径在30~100 nm的胞外囊泡,通过细胞被释放到细胞外液中~([1])。它们存在于生物体液中,诸如血液和脑脊液。外泌体携带有DNA、RNA、蛋白质和脂质等。由于外泌体的微泡结构为其内在的小分子提供了一个安全稳定的环境,同时这些信号小分子利用循环系统在胞间信号交换发挥重要作用,这让外泌体表现出一个成熟、稳定的信号传输系统~([2])。研究发现,外泌体中的m RNA和micro RNA     

miR-122-5p调节创伤性脑外伤后小胶质细胞极化减弱炎症反应北大核心CSCD

目的探讨miR-122-5p对创伤性脑外伤后小胶质细胞凋亡、极化和炎症反应的影响。方法建立创伤性脑外伤(traumatic brain injury,TBI)小鼠模型和细胞模型。使用TBI小鼠脑匀浆刺激星型胶质细胞产生外泌体,microRNA微阵列分析外泌体中显著改变的microRNA。实时荧光定量PCR检测TBI小鼠模型和TBI细胞模型中miR-122-5p表达。使用TUNEL凋亡染色、免疫荧光共聚焦、蛋白质印迹研究miR-122-5p抑制剂在TBI神经炎症中对小胶质细胞凋亡、小胶质细胞M1/M2表型转化、NLRP3通路及NFκB磷酸化的作用。结果通过microRNA微阵列分析发现有83个下调miRNA(改变2倍以上,P<0.05),其中miR-122-5p显著下调(P<0.01),miR-122-5p在TBI小鼠及细胞模型中表达显著下降[(1.0±0.00)vs.(0.41±0.15),P<0.001];[(1.0±0.00)vs.(0.34±0.07),P<0.001]。TUNEL凋亡检测、免疫荧光染色结果表明抑制miR-122-5p表达,可以显著减轻LPS诱导的小胶质细胞凋亡[(8.03±1.30)vs.(3.17±0.34),P<0.001],促进小胶质细胞M1向M2表型转化,即M1表型极化减少[(56.96±13.70)vs.(34.70±3.47),P=0.002],M2表型极化增加[(30.46±3.67)vs.(40.74±2.49),P=0.005]。蛋白质印迹结果表明miR-122-5p抑制剂降低NLRP3炎症小体活化[(0.77±0.10)vs.(0.51±0.11),P=0.02],降低NFκB的磷酸化[(0.73±0.08)vs.(0.50±0.07),P=0.003]。结论miR-122-5p在TBI星形胶质细胞分泌的外泌体及小胶质细胞中表达下调,miR-122-5p抑制剂可以通过抑制TBI后NLRP3炎症小体通路的活化及NFκB的磷酸化,促进小胶质细胞M1向M2表型转化,减少小胶质细胞凋亡,从而减轻TBI后小胶质细胞炎症损伤。