成纤维细胞系3T3细胞来源exosome对小鼠乳腺癌细胞增殖能力的影响

目的 观察小鼠成纤维细胞系3T3来源的外泌小体（exosome）对小鼠乳腺癌细胞4T1增殖能力的影响,并探索其中可能的机制。方法 PureExo Exosome提取试剂盒提取3T3细胞上清液中的exosome,按照不同浓度及时间作用于4T1细胞,CCK8法检测4T1细胞的增殖能力,BrdU/PI双掺入法测定细胞DNA合成及细胞周期;免疫印迹法（Western blot）及荧光定量实时PCR（qPCR）检测人表皮生长因子受体2（epidermal growth factor receptor-2, EGFR2,也称HER2）及下游PI3K/AKT信号转导通路相关蛋白的变化。利用HER2单克隆抗体靶向药物赫赛汀（Herceptin）,观察exosome是否影响4T1细胞对于Herceptin敏感度。结果 exosome处理组OD450吸光度值显著高于对照组（P<0.05）,细胞增殖及细胞周期进程加快。Western blot及qPCR实验提示随着exosome浓度的增加,HER2表达逐渐升高, AKT磷酸化水平增加。而同时给予exosome可明显增加4T1细胞对Herceptin的敏感度。结论 小鼠成纤维细胞系3T3来源exosome可促进小鼠乳腺癌细胞4T1增殖及周期进程,并且可能通过HER2激活其下游PI3K/AKT信号通路发挥上述作用。     

Tumor-derived exosomes: Nanovesicles made by cancer cells to promote cancer metastasis

Nanomedicine usually refers to nanoparticles that deliver the functional drugs and siRNAs to treat cancer. Recent research has suggested that cancer cells can also make nanoparticles that also deliver functional molecules in promoting cancer metastasis, which is the leading cause of various cancer mortalities. This nanoparticle is called tumor-derived vesicles, or better-known as tumor-derived exosomes (TEXs). TEXs are nanoscale membrane vesicles (30–140 nm) that are released continuously by various types of cancer cells and contain tumor-derived functional biomolecules, including lipids, proteins, and genetic molecules. These endogenous TEXs can interact with host immune cells and epithelial cells locally and systemically. More importantly, they can reprogram the recipient cells in favor of promoting metastasis through facilitating tumor cell local invasion, intravasation, immune evasion, extravasation, and survival and growth in distant organs. Growing evidence suggests that TEXs play a key role in cancer metastasis. Here, we will review the most recent findings of how cancer cells harness TEXs to promote cancer metastasis through modulating vascular permeability, suppressing systemic immune surveillance, and creating metastatic niches. We will also summarize recent research in targeting TEXs to treat cancer metastasis.     

星形胶质细胞外泌体对缺氧缺血神经元的保护作用

目的 探索星形胶质细胞外泌体对缺氧缺血神经元的影响。方法 体外培养大鼠星形胶质细胞,通过差速离心法获取细胞上清液中的外泌体。采用透射电镜、Nanosight和Western blot鉴定外泌体;采用BCA法检测外泌体蛋白浓度。体外培养大鼠神经元,分为对照组、外泌体组、氧糖剥夺（OGD）组和OGD+外泌体组（n=3）。OGD组和OGD+外泌体组给予无糖培养基和缺氧处理;外泌体组和OGD+外泌体组分别给予终浓度为22 μg/mL的外泌体处理,对照组和OGD组给予等体积PBS处理。采用ELISA法检测神经元乳酸脱氢酶（LDH）水平;TUNEL法检测神经元凋亡指数。结果 外泌体鉴定结果显示差速离心法提取的外泌体符合外泌体特点;与对照组和外泌体组相比,OGD组LDH值和凋亡指数显著增加（P < 0.05）;与OGD组相比,OGD+外泌体组LDH值和凋亡指数均显著降低（P < 0.05）。结论 星形胶质细胞来源的外泌体对神经元缺氧缺血损伤有保护作用。     

Exosome与肿瘤耐药的研究进展

Exosome是直径40～100 nm的微囊泡,内含蛋白质、mRNA、microRNA等生物活性物质.机体内几乎所有细胞都可分泌exosome.Exosome不仅是细胞-细胞间物质信息交流的通讯工具,还参与免疫调节、炎症反应、肿瘤发生和耐药等生理病理过程.该文就exosome与肿瘤耐药之间的关系作一综述.     

High expression of circulating exosomal circAKT3 is associated with higher recurrence in HCC patients undergoing surgical treatment

Exosome-enriched circular RNAs (circRNAs) have become new biomarkers of cancers. In this study, we examined the expression of exosomal circAKT3 and analyzed its association with clinicopathological features and prognosis of patients with hepatocellular carcinoma (HCC). CircAKT3 levels from circulating exosomes in 124 patients with HCC and 100 healthy subjects were measured by quantitative polymerase chain reaction. We defined higher circulating exosomal circAKT3 as > 1‐fold that of the healthy subjects. The expression of exosomal circAKT3 in HCC patients was significantly increased compared with healthy subjects. Patients with high circulating exosomal circAKT3 had higher tumor recurrence rates (hazard risk (HR), 3.14; 95% confidence interval (CI), 1.29–6.21, P = 0.012) and higher mortality (HR, 1.89; 95% CI, 1.04–3.01), P = 0.048). Survival analysis showed that the overall survival rate and recurrence-free survival rate of patients with high exosomal circAKT3 were lower than the patients had low exosomal circAKT3. In conclusion, high circulating exosomal circAKT3 is associated with a higher risk of HCC recurrence and mortality. Follow-up of HCC patients with high exosomal circAKT3 after surgery may help to reduce the risk of recurrence and improve prognosis.     

奥沙利铂联合Exosome诱导的效应性T细胞抑制HepG2细胞增殖的研究

目的观察奥沙利铂(OXA)联合负载HepG2细胞裂解物的Exosome诱导的效应性T细胞对肝癌HepG2细胞系增殖的抑制作用。方法自健康人外周血中提取单个核细胞和T淋巴细胞,并以GM-CSF+IL-4的培养方案获得树突状细胞(DC)。将反复冻融后产生的HepG2细胞裂解物体外致敏DC,收集培养上清后以超高速离心法分离得到Exosome,电镜下观察其形态特征。用致敏DC及其分泌的Exosome刺激T淋巴细胞的增殖和活化。以ELISA试验检测不同刺激环境下T细胞分泌IL-1β、IL-2、IL-4、IL-6、IL-10、IFN-γ和TNF-α的能力。以细胞杀伤实验(MTT法)检测不同因素刺激后的T细胞、OXA(2.5、5.0、10.0mg.L-1)以及两者联合应用对HepG2细胞生长的抑制效应。结果与未致敏DC及其分泌的Exosome相比,HepG2细胞冻融裂解物致敏的DC及其分泌的Exosome能显著促进T细胞的增殖,并使其活化和分泌大量的IL-1β、IL-2、IL-6、IFN-γ和TFN-α等Th1型细胞因子。活化后的T细胞、OXA以及两者联合应用对HepG2细胞体外增殖均有抑制作用,而活化T细胞联合10mg.L-1OXA对HepG2细胞的杀伤率最高,但与联合5 mg.L-1OXA的效应相比,差异无统计学意义(P0.05)。结论负载肿瘤细胞抗原的DC所分泌的Exosome可在体外刺激T细胞,使其活化为具有抗肿瘤效应的细胞毒性T细胞,该细胞联合低浓度OXA能显著抑制肝癌细胞的体外增殖,并降低OXA的用量。     

外泌体在恶性肿瘤放疗中的研究进展

外泌体是细胞分泌的直径在30~120 nm的具有生物学活性的盘状囊泡,参与恶性肿瘤的侵袭、转移及多药耐药等诸多方面。在放射治疗领域,目前已证实放射线所引起的肿瘤细胞外泌体分泌的变化,可影响细胞间的通讯作用,同时增加肿瘤细胞的放射线抗性。本文就外泌体在恶性肿瘤放疗中的研究进展作一综述。     

小鼠CD4~+T细胞外泌体分离及鉴定

目的探讨CD4~+T细胞是否具有分泌外泌体的能力,以及CD4~+T细胞外泌体参与炎症及肿瘤免疫过程的可能。方法应用断颈处死的方法取出小鼠的脾脏,用磁珠分选的方法从小鼠脾脏细胞中分选出CD4~+T细胞,并尝试从培养基上清液中提取CD4~+T细胞的外泌体,在透射电镜下观察,后用PCR技术分析miR-23a、miR-214的表达情况。结果在透射电镜下能够观察到提取出的CD4~+T细胞外泌体,且用PCR技术能检测到小鼠CD4~+T细胞外泌体中miR-23a、miR-214这两个炎症及肿瘤相关的miRNA的表达。结论小鼠CD4~+T细胞有分泌外泌体的能力,且为CD4~+T细胞外泌体参与炎症及肿瘤相关过程提供了可能。     

外泌体miRNA在肺癌诊疗中的研究进展

外泌体是一种几乎所有细胞都能分泌的胞外小泡,在细胞和器官之间运输脂质、蛋白质和核酸。作为一种天然细胞间通信器,外泌体广泛分布在生物体液中。外泌体中的微小RNA(miRNA)在肿瘤的发生、发展和侵袭转移中起至关重要的作用,并具有成为肿瘤生物标志物的潜力。本文综述了外泌体中miRNA在肺癌诊断、预后评估及药物疗效预测中的作...