肿瘤来源的胞外体对肿瘤进展的影响

胞外体是真核细胞在正常生理过程中分泌的一种具有多种细胞膜结构的小囊泡,作为一类重要的细胞间信号分子,胞外体具有多种生物活性成分,其异常分泌是恶性肿瘤的标志.胞外体与肿瘤细胞生长、肿瘤血管生成、免疫抑制及化疗耐药关系密切.因此,探究胞外体的形成过程、主要组成成分及肿瘤相关的胞外体在肿瘤进展、免疫调节中的作用有助于进一步了解肿瘤进展过程,具有重要意义.     

Exosomal miR-1228 From Cancer-Associated Fibroblasts Promotes Cell Migration and Invasion of Osteosarcoma by Directly Targeting SCAI

Cancer-associated fibroblasts (CAFs) play a predominant role in regulating tumor progression. Understanding how CAFs communicate with osteosarcoma is crucial for developing novel approaches for osteosarcoma therapy. Exosomes are able to transmit messages between cells. In this study, we demonstrated that CAFs transfer exosomes to osteosarcoma cells, which promotes osteosarcoma cell migration and invasion. Using a miRNA microarray analysis, we identified 13 miRNAs that are significantly increased in exosomes derived from cancer-associated fibroblasts (CAFs) and corresponding paracancer fibroblasts (PAFs). In vitro studies further validated that the levels of microRNA-1228 (miR-1228) were increased in CAFs, its secreted exosomes, and in recipient osteosarcoma cells, which can downregulate endogenous SCAI mRNA and protein level in osteosarcoma. Furthermore, our findings demonstrate that SCAI was downregulated in osteosarcoma tissues. Taken together, this study provides evidence that CAF exosomal miR-1228 is able to promote osteosarcoma invasion and migration by targeting SCAI, which may represent a critical therapeutic target for osteosarcoma treatment.     

肾癌细胞来源exosome的制备和免疫相关蛋白组成的初步研究

目的:分离纯化肾癌细胞分泌的exosome,检测exosome免疫相关蛋白的组成,探讨其潜在的临床应用价值.方法:体外培养人肾癌细胞株Rc-2.用超滤和蔗糖重水密度梯度超速离心法分离纯化exosome,透射电镜观察其形态,Western blot检测其免疫相关蛋白的组成.结果:用超滤和蔗糖重水密度梯度超速离心法成功分离出exosome.透射电镜下exosome为类圆碟形,具有双层膜结构,直径30-100 nm.exosome表达肾癌特异性抗原G250、热休克蛋白70(Heat shock protein70,HsP70)和细胞间粘附分子(Intercellular Adhesion Molecule-1,ICAM-1).结论:超滤和蔗糖重水密度梯度超速离心法可以分离纯化肾癌细胞分泌的exosome,exosome表达免疫相关蛋白G250、HSP70、ICAM-l.其负载肾癌特异性抗原,具有免疫原性,可望成为治疗肾癌的新疫苗.     

外泌体在卵巢癌发病及诊疗中的研究进展

卵巢癌是死亡率最高的妇科恶性肿瘤,由于缺乏特异性标志物,早期诊断存在很大困难。外泌体是近年多种领域的研究热点,其分布广泛,内容丰富,功能多变,越来越多地进入肿瘤研究领域。外泌体可来源于多种细胞和体液,通过运载多种蛋白、脂质、mRNA及miRNA片段等生物学功能物质,介导细胞-细胞间信息交流,促进肿瘤的发生、发展。此外,由于肿瘤相关外泌体可表达特异性抗原,这为肿瘤的诊断与治疗提供了新思路。就外泌体在卵巢癌发生、发展、诊断和治疗中的研究进行综述,以期更确切、更全面揭示外泌体在卵巢癌中的作用机制,为新的治疗方法提供理论基础。     

Endogenous and exogenous miR-520c-3p modulates CD44-mediated extravillous trophoblast invasion

IntroductionAdequate extravillous trophoblast (EVT) invasion is essential for successful placentation. Although miR-520c-3p plays an important role in CD44-mediated invasion in cancer cells, there is little information on whether miR-520c-3p is involved in the regulatory mechanisms of CD44-mediated EVT invasion.MethodsWe screened first trimester trophoblast cells and trophoblast cell lines for expression of miR-520c-3p using real-time polymerase chain reaction. The cell invasion assay was performed using EVT cell lines, HTR8/SVneo and HChEpC1b, to investigate the capability of suppressing EVT invasion by miR-520c-3p. Laser microdissection analysis was then used to determine whether miR-520c-3p was present in the first trimester decidua. Finally, the possibility of chorionic villous trophoblast (CVT)-EVT communication via exosomal miR-520c-3p was determined using an in vitro model based on BeWo exosomes and the EVT cell lines as recipient cells.ResultsThe miR-520c-3p level was significantly downregulated in EVT cell lines and EVTs. Cell invasion was significantly inhibited in miR-520c-3p-overexpressing cell lines, involving a significant reduction of CD44. Laser microdissection analysis showed that miR-520c-3p in the periarterial area of the decidua was significantly higher than that in the non-periarterial area. Using an in vitro model system, BeWo exosomal miR-520c-3p was internalized into the EVT cells with subsequently reduced cell invasion via CD44 repression.ConclusionsEVT invasion is synergistically enhanced by the reciprocal expression of endogenous miR-520c-3p and CD44. The present study supports a novel model involving a placenta-associated miRNA function in cell-cell communication in which CVT exosomal miR-520c-3p regulates cell invasion by targeting CD44 in EVTs.     

Exosomes from marrow stromal cells expressing miR-146b inhibit glioma growth

Exosomes are 30–150 nm vesicles secreted by a wide range of mammalian cells that can contain microRNA (miRNA). To test if marrow stromal cell (MSC) exosomes could be used as a vehicle for delivery of anti-tumor miRNAs, we transfected MSCs with a miR-146b expression plasmid, and harvested exosomes released by the MSCs. Intra-tumor injection of exosomes derived from miR-146-expressing MSCs significantly reduced glioma xenograft growth in a rat model of primary brain tumor.     

结直肠癌中差异性表达的外泌体lncRNA功能富集及通路分析

目的 通过探讨差异性表达的外泌体lncRNA及其调控的信号通路在结直肠癌发生、发展中的作用,以期为结直肠癌的诊断和治疗提供新的靶点.方法 使用R软件线性回归模型软件包limma包进行差异表达分析,根据筛选阈值得到显著差异表达的lncRNA和mRNA;通过计算差异表达lncRNA与mRNA皮尔逊相关性系数,获得其之间协同...     

Exosome在细菌和病毒感染中的作用研究

【摘要】外泌题（Exosome）作为生物活性载体,最早被认为仅仅负责细胞垃圾清运工作;然而近年来大量关于exosome与人类免疫缺陷病毒、乙型肝炎病毒、结核分枝杆菌以及其他病原体的研究成果,揭示了exosome功能的复杂性和多样性,如转运和传送各种调节因子、病原体核酸和蛋白质以及宿主细胞的miRNA和细胞因子至未感染细胞,以调节机体的免疫应答。Exosome既可以激活免疫促进炎症反应,也可以抑制免疫反应助力病毒的扩散。本文对exosome在细菌性和病毒性感染中扮演的角色及相关机制作一综述。     

以树突细胞为基础的抗乙型肝炎病毒免疫治疗现状与展望

DC是强大的APC,制备HBV抗原特异性DC疫苗,诱生抗原特异性CTL,可以有效控制HBV感染;DC还可分泌Exosome,后者作为新型非细胞结构性疫苗,有望成为抗HBV免疫治疗的生力军。     

血浆外泌体miR-210、miR-21和miR-4639对肾移植术后并发慢性移植肾肾病的诊断价值

目的检测肾移植受者术后血浆外泌体miR-21、miR-210和miR-4639表达变化，分析外泌体miR-21、miR-210和miR-4639单独及联合对肾移植术后并发慢性移植肾肾病(CAN)的诊断价值。 方法回顾性分析2018年1月至2019年1月苏州大学附属第三医院泌尿外科实施的同种异体肾移植受者临床资料，最终纳入34例受者，根据肾移植术后是否发生CAN将其分为CAN组及对照组。采用凝胶排阻色谱法提取血浆外泌体，采用Nanosight NS300分析外泌体粒径，采用蛋白质印迹法(WB)分析外泌体表面标志物(CD63和Alix)表达情况。采用卡方检验比较CAN组和对照组受者性别比例。采用成组t检验比较两组受者移植前年龄、末次血清肌酐、血清尿素氮和估算肾小球滤过率(eGFR)。采用受试者工作特征(ROC)曲线评价血浆外泌体miR-210、miR-21和miR-4639对肾移植术后并发CAN的诊断效能。P<0.05为差异有统计学意义。 结果CAN组(n＝18例)和对照组(n＝16例)受者性别以及移植前年龄、末次血清肌酐、血清尿素氮和eGFR差异均无统计学意义(χ²＝0.04、t＝0.86、-1.84、-1.83和0.85，P均>0.05)。透射电镜、Nanosight NS300及WB检测结果均提示提取样本为血浆外泌体。CAN组与对照组血浆外泌体miR-210、miR-21和miR-4639相对表达量差异均有统计学意义(t＝4.13、3.38和2.33，P均<0.05)。miR-210预测肾移植术后并发CAN的ROC曲线下面积为0.854(95%CI：0.730～0.979，P<0.05)，当截断值＝1.320时，敏感度为66.7%，特异度为93.8%。miR-21预测肾移植术后并发CAN的ROC曲线下面积为0.774(95%CI：0.618～0.931，P<0.05)，当截断值＝1.243时，敏感度为55.6%，特异度为93.8%。miR-4639预测肾移植术后并发CAN的ROC曲线下面积为0.670(95%CI：0.482～0.859，P<0.05)，当截断值＝0.936，敏感度为66.7%，特异度为75.0%。随后，构建基于miR-210、miR-21和miR-4639 3个指标的联合诊断模型，回归方程z＝5.293×[miR-210]＋5.046×[miR-21]＋0.433×[miR-4639]-13.373，联合预测概率值p＝e^z/(1＋e^z)。miR-210、miR-21和miR-4639联合预测肾移植术后并发CAN的ROC曲线下面积为0.938(95%CI：0.860～1.015，P<0.05)，当截断值＝0.587，敏感度为83.33%，特异度为93.75%。当联合预测值为0.587时，CAN组有83.3%(15/18)的个体被联合预测模型诊断出阳性结果，而对照组有93.8%(15/16)的个体被联合预测模型诊断出阴性结果，表明该联合预测模型有较好的诊断价值。 结论miR-210、miR-21和miR-4639组成的miRNA阵列可能可以用于早期诊断肾移植术后并发CAN。