Human bone marrow mesenchymal stem cell-derived extracellular vesicles impede the progression of cervical cancer via the miR-144-3p/CEP55 pathway

Cervical cancer is the most common gynaecological malignancy, with a high incidence rate and mortality rate in middle-aged women. Human bone marrow mesenchymal stem cells (hBMSCs) have been implicated in the initiation and subsequent development of cancer, along with the involvement of extracellular vesicles (EVs) mediating intracellular communication by delivering microRNAs (miRNAs or miRs). This study is aimed at investigating the physiological mechanisms by which EVs-encapsulated miR-144-3p derived from hBMSCs might mediate the progression of cervical cancer. The expression profiles of centrosomal protein, 55 Kd (CEP55) and miR-144-3p in cervical cancer cell lines and tissues, were quantified by RT-qPCR and Western blot analysis. The binding affinity between miR-144-3p and CEP55 was identified using in silico analysis and luciferase activity determination. Cervical cancer cells were co-cultured with EVs derived from hBMSCs that were treated with either miR-144-3p mimic or miR-144-3p inhibitor. Cervical cancer cell proliferation, invasion, migration and apoptosis were detected in vitro. The effects of hBMSCs-miR-144-3p on tumour growth were also investigated in vivo. miR-144-3p was down-regulated, whereas CEP55 was up-regulated in cervical cancer cell lines and tissues. CEP55 was targeted by miR-144-3p, which suppressed cervical cancer cell proliferation, invasion and migration and promoted apoptosis via CEP55. Furthermore, similar results were obtained by hBMSCs-derived EVs carrying miR-144-3p. In vivo assays confirmed the tumour-suppressive effects of miR-144-3p in hBMSCs-derived EVs on cervical cancer. Collectively, hBMSCs-derived EVs-loaded miR-144-3p impedes the development and progression of cervical cancer through target inhibition of CEP55, therefore providing us with a potential therapeutic target for treating cervical cancer.     

电刺激大鼠脚内核对脚桥核神经元放电的影响

目的:观察电刺激大鼠脚内核(EP)对大鼠脚桥核(PPN)神经元自发放电的影响,进一步探讨脑内电刺激治疗帕金森病(PD)的机制。方法:应用细胞外记录的方法观察不同频率电刺激(强度0.6 mA,波宽0.06 ms,时程5 s,频率5 Hz、10Hz、20Hz、50Hz、100Hz、150Hz、200Hz)大鼠EP对PPN神经元放电的影响。结果:实验记录了大鼠33个神经元的自发放电,其放电频率在3.6~52.2Hz之间,平均为(15.95±8.56)Hz;当刺激频率为100Hz时,抑制效应最显著(P<0.05)。结论:高频电刺激大鼠EP对PPN神经元自发放电的影响主要为抑制作用,提示高频刺激EP可通过抑制PPN神经元活动参与PD的治疗。     

不同频率电刺激膈神经导致膈肌肌浆网Ca~(2 )-ATPase和Ca~(2 )释放-摄取动力学改变

研究不同频率慢性电刺激（ＣＥＳ）后兔膈肌肌浆网（ＳＲ）Ｃａ２＋－ＡＴＰａｓｅ活性以及ＳＲ Ｃａ２＋摄取－释放动力学对不同频率ＣＥＳ的适应性变化。建立不同频率ＣＥＳ组;用定磷法测定ＳＲ Ｃａ２＋－ＡＴＰａｓｅ活性;用Ｆｕｒａ－２荧光法测定ＳＲ　Ｃａ２＋摄取－释放动力学。与对照组比较,慢性低频电刺激１０ Ｈｚ和２０Ｈｚ组的ＳＲ　Ｃａ２＋－ＡＴＰａｓｅ活性明显降低（Ｐ＜０．０１）,Ｃａ２＋释放－摄取动力学也显著降低（Ｐ＜０．０１）;慢性高频电刺激５０ Ｈｚ和１００Ｈｚ组的ＳＲ Ｃａ２＋－ＡＴＰａｓｅ活性则显著升高（Ｐ＜０．０１）,Ｃａ２＋释放－摄取动力学亦明显升高（Ｐ＜０．０１）。实验提示,ＣＥＳ后不同频率ＣＥＳ导致膈肌ＳＲＣａ２＋－ＡＴＰａｓｅ、Ｃａ２＋摄取－释放动力学产生不同的适应性变化;对不同功能状态的膈肌应用不同频谱的慢性电刺激可能具有重要的临床意义。     

细菌Enterobacter dissolvens的电解刺激连续培养过程研究

以葡萄糖为唯一碳源,研究了细菌Enterobacter dissolvens在直流电条件下的连续培养过程。实验表明在电解刺激下的连续培养,细胞生长曲线和葡萄糖代谢速率均显著提高。当采用10mA电流通电10h后,菌液中细胞的比脱氢酶活[总显色度（OD490）／细胞量（OD600）]约为参比样的2倍,而葡萄糖降解率也为参比测量值的1．8倍,细胞生长亦有所加快。由于培养基的流加,使得过氧化氢等中间产物得到稀释,从而避免了细胞生长的衰减。     

Signaling through cholesterol esterification: a new pathway for the cholecystokinin 2 receptor involved in cell growth and invasion

Several studies indicate that cholesterol esterification is deregulated in cancers. The present study aimed to characterize the role of cholesterol esterification in proliferation and invasion of two tumor cells expressing an activated cholecystokinin 2 receptor (CCK2R). A significant increase in cholesterol esterification and activity of Acyl-CoA:cholesterol acyltransferase (ACAT) was measured in tumor cells expressing a constitutively activated oncogenic mutant of the CCK2R (CCK2R-E151A cells) compared with nontumor cells expressing the wild-type CCK2R (CCK2R-WT cells). Inhibition of cholesteryl ester formation and ACAT activity by Sah58-035, an inhibitor of ACAT, decreased by 34% and 73% CCK2R-E151A cell growth and invasion. Sustained activation of CCK2R-WT cells by gastrin increased cholesteryl ester production while addition of cholesteryl oleate to the culture medium of CCK2R-WT cells increased cell proliferation and invasion to a level close to that of CCK2R-E151A cells. In U87 glioma cells, a model of autocrine growth stimulation of the CCK2R, inhibition of cholesterol esterification and ACAT activity by Sah58-035 and two selective antagonists of the CCK2R significantly reduced cell proliferation and invasion. In both models, cholesteryl ester formation was found dependent on protein kinase zeta/ extracellular signal-related kinase 1/2 (PKCζ/ERK1/2) activation. These results show that signaling through ACAT/cholesterol esterification is a novel pathway for the CCK2R that contributes to tumor cell proliferation and invasion.     

布比卡因致心肌细胞线粒体损伤大鼠模型的建立

目的观察电刺激下布比卡因心肌细胞线粒体形态变化及活性氧(reactive oxygen species, ROS)生成量,探讨建立理想的布比卡因中毒的大鼠心肌细胞模型。方法采用Langendroff装置新鲜分离雄性SD大鼠心肌细胞,细胞计数后将其转移至doff管中随机分为四组:DMEM静置组、DMEM电刺激组、布比卡因静置组、布比卡因电刺激组。实验重复五次。采用透射电镜观察心肌细胞线粒体形态,并使用多功能微孔板检测仪测量ROS生成量。结果 DMEM电刺激组线粒体肿胀程度及ROS生成量与DMEM静置组相比差异无显著性(P> 0.05);而布比卡因电刺激组线粒体肿胀程度明显高于布比卡因静置组(P=0.000),且ROS生成量也明显升高(P<0.05)。结论电刺激下心肌细胞呈节律性收缩,能更好地模拟临床布比卡因中毒时心肌线粒体损伤。     

表达人乳头瘤病毒16型E6/E7融合蛋白的非复制型重组痘苗病毒的构建及免疫效果观察

采用基因工程方法将HPV16E6、E7基因融合后插入痘苗病毒载体,通过同源重组构建表达人乳头瘤病毒16型E6/E7融合蛋白的非复制型重组痘苗病毒疫苗,用C57BL/6小鼠观察其免疫原性和抗肿瘤移植情况。测序结果表明融合的HPV16E6、E7基因序列与设计相符;构建的非复制型重组痘苗病毒经Dot blot鉴定,显示有E6、E7融合基因的插入;Western blot检测表明该重组病毒在鸡胚成纤维细胞中能表达HPV16型E6/E7融合蛋白。动物免疫试验表明,该重组病毒在小鼠体内可诱发E6、E7特异性抗体;被免疫小鼠能抵抗TC-1肿瘤细胞的攻击。此结果为将来进一步研制HPV16、18型联合疫苗打下了基础。     

电刺激大鼠脊神经皮支对远距离机械感受单位电活动的影响

实验采用分离神经细束的方法,观察逆行电刺激大鼠脊神经背侧皮支后,在相距较远的神经细束上记录到的Aδ和C类机械感受单位电活动的变化。刺激T9脊神经背侧皮支,在T12神经细束上记录到59.3%（16/27）的Aδ和71.2%(37/52）的C类单位在刺激后90～120s放电显著增加。刺激T8脊神经背侧皮支,在T12神经细束上记录到47.8%(11/23）的Aδ单位和36.6%(15/41）的C类单位在刺激后120～150s放电显著增加。大多数单位（18/23）的机械感受阈值在电刺激远距离脊神经背侧皮支后降低。结果表明,逆行电刺激外周感觉神经,可以使相距较远的Aδ和C类机械感受单位致敏,其传入放电增加。     

阿霉素处理的肿瘤抗原致敏树突状细胞的抗肿瘤免疫研究

研究表明化疗药物作用于肿瘤细胞后可有效激发免疫应答,这与肿瘤细胞的性质和化疗药物有关。该研究主要探讨阿霉素（adriamycin,ADM）处理小鼠宫颈癌u14细胞获得的肿瘤抗原致敏树突状细胞（dendriticceils,DCs）的免疫应答及对肿瘤的杀伤效应。分别应用ADM和反复冻融法处理小鼠宫颈癌U14细胞,取其离心上清液,致敏小鼠骨髓来源的DC,观察DC诱导的淋巴细胞增殖反应和细胞毒性T淋巴细胞（cytotoxicTlymphocyte,CTL）对宫颈癌细胞的细胞毒效应。结果显示：ADM处理的U14细胞抗原致敏后的DC组所激发和扩增的T细胞数及对宫颈癌细胞的杀伤效果显著高于对照组（P〈0．05）。因而提示ADM处理的肿瘤抗原能有效地致敏DC并产生抗肿瘤免疫效应。