Changes in microRNA (miRNA) expression during pancreatic cancer development and progression in a genetically engineered KrasG12D;Pdx1-Cre mouse (KC) model

Differential expression of microRNAs (miRNAs) has been demonstrated in various cancers, including pancreatic cancer (PC). Due to the lack of tissue samples from early-stages of PC, the stage-specific alteration of miRNAs during PC initiation and progression is largely unknown. In this study, we investigated the global miRNA expression profile and their processing machinery during PC progression using the Kras^G12D;Pdx1-Cre (KC) mouse model. At 25 weeks, the miRNA microarray analysis revealed significant downregulation of miR-150, miR-494, miR-138, miR-148a, miR-216a, and miR-217 and upregulation of miR-146b, miR-205, miR-31, miR-192, and miR-21 in KC mice compared to controls. Further, expression of miRNA biosynthetic machinery including Dicer, Exportin-5, TRKRA, and TARBP2 were downregulated, while DGCR8 and Ago2 were upregulated in KC mice. In addition, from 10 to 50 weeks of age, stage-specific expression profiling of miRNA in KC mice revealed downregulation of miR-216, miR-217, miR-100, miR-345, miR-141, miR-483-3p, miR-26b, miR-150, miR-195, Let-7b and Let-96 and upregulation of miR-21, miR-205, miR-146b, miR-34c, miR-1273, miR-223 and miR-195 compared to control mice. Interestingly, the differential expression of miRNA in mice also corroborated with the miRNA expression in human PC cell lines and tissue samples; ectopic expression of Let-7b in CD18/HPAF and Capan1 cells resulted in downregulation of KRAS and MSST1 expression. Overall, the present study aids an understanding of miRNA expression patterns during PC pathogenesis and helps to facilitate the identification of promising and novel early diagnostic/prognostic markers and therapeutic targets.     

树突状细胞在肿瘤中的研究进展

肿瘤的发生、发展与机体免疫状态密切相关。树突状细胞(DCs)是众多免疫细胞中的一种,具有专职抗原提呈功能,在肿瘤免疫过程中发挥关键的调节作用。肿瘤机体中DCs处于异常状态,如成熟障碍、功能异常和表型改变等,无法激活抗肿瘤的特异性免疫反应。目前,基于DCs的肿瘤免疫疗法备受关注,例如通过促进DCs成熟或者利用修饰过的DCs激活机体靶向肿瘤的免疫反应。本文拟对肺癌、结直肠癌、乳腺癌及肝癌等肿瘤中DCs异常相关机制研究以及临床关于DCs疫苗的研究作一综述。     

Spontaneous hybridization of macrophages and Meth A sarcoma cells

We present evidence of hybridization between Meth A sarcoma cells and syngeneic as well as semigeneic peritoneal macrophages. The resultant hybrids are characterized by morphology, membrane markers, ploidy, chromosomal content and functional features. Briefly, after a few days of coculture, cells appeared with morphology intermediate between the 2 original cell types. Typical macrophage surface molecules appeared in the hybrids. Meth A cells were labeled with red fluorescence and macrophages with green fluorescence. After 4 days in vitro, hybrids with yellow fluorescence appeared. Macrophages from BALB.K mice (H-2 K(k)) were cocultivated with Meth A cells from BALB/c mice (H-2 K(d)). The semigeneic hybrids displayed both specificities, as demonstrated by flow cytometry. The hybrids appeared moderately phagocytic, less so than the macrophages and markedly more so than the essentially nonphagocytic Meth A cells. The hybrids had a mean number of 76 chromosomes, as opposed to 53 in the Meth A cells and 40 in the macrophages. The macrophage DNA index was set at 1; Meth A cells were found to have an index of 1.6 in G1 phase, and the hybrids had a 2.6 index. The hybrids grew more slowly in vitro than Meth A cells, but grew faster in vivo.     

miR－647在结肠癌细胞中的表达及临床意义

目的：分析miR－647在结肠癌组织及细胞系中的表达情况,探讨其对结肠癌细胞增殖、迁移能力的影响及其可能的作用机理。方法：利用Real－time quantitative Polymerase Chain Reaction（qPCR）技术检测17例结肠癌患者癌及癌旁组织中miR－647的表达;利用qPCR技术检测正常人肠上皮细胞HIEC及结肠癌细胞HT－29中miR－647的表达;将miR－647 antagomir及对照分别转染至结肠癌细胞中,应用MTT实验检测细胞增殖,体外划痕实验检测细胞迁移能力,评价转染miR－647抑制剂对结肠癌细胞增殖能力和迁移能力的影响。结果：qPCR结果显示,与癌旁组织相比,miR－647在结肠癌肿瘤组织中表达明显升高;与正常人肠上皮细胞相比,人结肠癌细胞系HT－29中miR－647表达明显升高;MTT结果显示miR－647抑制剂可以显著抑制SW480和SW620细胞的增殖能力和细胞迁移能力。结论：miR－647通过促进结肠癌细胞的增殖和迁移能力,参与结肠癌的发生发展进程。     

Comparison of gene expression data from human and mouse breast cancers: identification of a conserved breast tumor gene set

The aim of our work was to establish a database for breast cancer gene expression data in order to compare human and mouse breast cancer. We identified human and mouse homologues genes and compared the expression profile of 24 human breast tumors with 6 WAP-SVT/t breast tumors (WAP-SVT/t animals, line 8). Our studies confirmed the heterogeneity in gene expression of human as well as mouse breast cancer cells. However, 63 genes were found to be differentially expressed (upregulated: 40; downregulated: 23 genes) in at least 75% of the breast tumors of both species. To differentiate between early and late events in tumor formation, we compared the 63 differentially expressed genes with a mouse data set obtained from hyperplastic mammary glands. This revealed that the majority of the early deregulated genes are cell proliferation specific. These early changes seem to be necessary although not sufficient for breast cancer formation. Late alterations concern mainly genes belonging to the category of cell communication and metabolism. Interestingly, most of the 63 conserved genes are commonly associated with tumorigenesis.     

小鼠后肾集合管水通道蛋白表达及其上皮细胞超微结构研究

目的观察小鼠后肾集合管水通道蛋白(AQP)-4的表达及其上皮细胞超微结构变化。方法应用透射电镜、免疫组织化学及图像分析技术观察并检测小鼠后肾不同发育阶段集合管的超微结构及AQP-4表达。结果小鼠胚龄18 d见发育早期集合管主细胞,生后7 d～21 d,其形态结构发育基本完善。A型闰细胞于胚胎18 d出现,B型闰细胞生后21天出现。AQP-4于胚龄14 d始见表达,分布于集合管管壁上皮细胞侧基底细胞膜,随胚龄增加表达逐渐增强,生后1 d达高峰。结论集合管管壁上皮细胞于胚胎时出现,但其形态结构在生后才逐渐完善。AQP-4对小鼠胚胎时期肾水平衡调节可能起重要的作用。     

肿瘤相关巨噬细胞对膀胱癌细胞增殖和血管生成的影响

目的:探讨肿瘤相关巨噬细胞（TAMs）对膀胱癌细胞增殖和血管生成的影响。方法:采用巨噬细胞U937的上清液培养膀胱癌细胞系T24,CCK-8法检测膀胱癌细胞的增殖能力;流式细胞术检测其对细胞周期的影响;通过实时荧光定量PCR和Western blot检测膀胱癌细胞中血管内皮生长因子（VEGF）的mRNA和蛋白表达以及AKT磷酸化水平。结果:CCK-8结果表明TAMs促进膀胱癌细胞的增殖;流式结果显示TAMs能促进细胞周期G1-S期转换;实时荧光定量PCR和Western blot 结果显示TAMs促进膀胱癌细胞内VEGF的mRNA和蛋白表达,并促进AKT磷酸化。结论:TAMs促进细胞周期G1-S期转换,促进AKT磷酸化和VEGF的表达,且TAMs有望成为膀胱癌治疗和预后判断新的靶点。     

移植后树突状细胞、亚群重建规律及其与急性移植物抗宿主病的关系

 异基因干细胞移植后树突状细胞（DC）恢复的特点是移植后DC细胞亚群均较移植前水平低,单核细胞样DC在移植后300 ~ 400 d可以恢复正常水平,浆细胞样DC恢复很慢。它的重建受到粒细胞刺激因子、前炎性的细胞因子及间充质干细胞的影响,与异基因移植CD+34剂量无关。通过分析DC与移植物抗宿主病关系的分析,发现低数量的DC会导致高的GVHD的发生率,并有学者对这种现象的机制进行了解释。就移植后树突状细胞、亚群重建规律及其与急性移植物抗宿主病的关系的主题进行综述。     

胚胎小鼠肾脏发育过程中eNOS表达与细胞凋亡的关系

目的观察胚胎小鼠不同发育阶段肾组织中内皮型一氧化氮合酶（eNOS）的表达和细胞凋亡的特征,探讨eNOS与细胞凋亡的关系。方法应用原位末端标记（TUNEL）法检测胚胎小鼠肾组织中的细胞凋亡,免疫组织化学方法和体视学方法检测eNOS的表达。结果不同发育阶段的肾组织中均可见到TUNEL染色阳性的细胞,凋亡指数从E14d开始增高,E18d达到高峰。eNOS表达于皮质生肾区、近端小管和远端小管,表达量随着发育逐渐增加。结论细胞凋亡和eNOS的表达在小鼠肾脏胚胎发育过程中具有重要的作用,细胞凋亡与eNOS的表达有一定的相关性。     

微小RNA Let-7在子宫肌瘤组织中的表达情况及与复发相关危险因素的探讨

目的:探讨单发、多发子宫肌瘤、不同直径子宫肌瘤以及肌瘤与相应肌壁组织中miRNA Let-7的表达情况,探讨miRNA Let-7与子宫肌瘤复发危险因素的关系.方法:运用实时定量聚合酶链反应(real-time,PCR)方法分别检测单发肌瘤与多发子宫肌瘤、不同直径的肌瘤组织以及对应肌壁组织中miRNA Let-7的相对...     

微小RNA 933靶向调控BDNF表达及对肝癌细胞迁移侵袭的影响#br#

目的探讨微小RNA 933（miR 933）对脑源性神经营养因子（BDNF）的靶向调控作用及肝癌细胞迁移侵袭的影响。 方法收集本院2017年1月至2017年12月经手术切除的30例肝癌组织及对应癌旁组织,采用实时定量PCR（QPCR）检测以上组织和肝癌细胞（Huh7、HepG2和SK Hep 1）中的miR 933水平;采用脂质体法向SK Hep 1细胞分别转染miR 933模拟物（过表达组）和miR 933阴性对照（对照组）,采用QPCR法检测转染48 h后各组的miR 933水平以评价转染效率;分别采用Transwell和划痕实验检测各组的侵袭和迁移情况;QPCR和Western blotting分别检测各组的BDNF mRNA和蛋白水平;双荧光素酶报告基因实验验证miR 933与BDNF之间靶向关系和结合位点。 结果肝癌组织中的miR 933水平为0351±0026,低于癌旁组织的1124±0054,差异有统计学意义（P＜005）;Huh7、HepG2和SK Hep 1细胞系中miR 933水平分别为0751±0062、0453±0057和0017±0006,均低于健康肝细胞系L02,差异有统计学意义（P＜005）;过表达组转染48 h后SK Hep 1细胞的miR 933水平为3197±0354,高于对照组的1019±0079,差异有统计学意义（P＜005）。过表达组的愈合率和穿膜细胞数分别为（244±39）％和（576±68）个,均低于对照组的（625±47）％和（1026±95）个（P＜005）。过表达组的BDNF mRNA和蛋白水平均低于对照组（P＜005）。双荧光素酶报告实验结果显示,miR 933显著抑制野生型BDNF 3’UTR质粒转染细胞的荧光素酶活性（P＜005）,但对突变型BDNF 3’UTR荧光素酶活性无影响（P＞005）。 结论miR 933在肝癌组织和细胞中水平下调,且可抑制肝癌细胞的侵袭迁移,可能是通过靶向调控BDNF来实现,可作为肝癌的潜在治疗靶点。     

Spatiotemporal co-dependency between macrophages and exhausted CD8+ T cells in cancer

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经典激活巨噬细胞促进乳腺癌细胞贴壁和非贴壁克隆形成

目的 探讨经典激活巨噬细胞(M1)对乳腺癌细胞贴壁和非贴壁克隆形成的影响,进一步阐明M1促乳腺癌进展的作用.方法 用密度梯度离心法,从健康成人外周血中分离单个核细胞,体外诱导M1.在乳腺癌细胞与巨噬细胞的无血清共培养体系中,做平板克隆实验;在M1-乳腺癌细胞软琼脂培养体系中,做非贴壁克隆形成实验,检测M1对乳腺癌贴壁克隆和非贴壁克隆形成的影响.结果 在M1的作用下,乳腺癌SK-3rd细胞贴壁克隆和非贴壁克隆形成的能力均增强(P＜0.001).结论 M1促进乳腺癌细胞贴壁克隆和非贴壁克隆的形成.     

Attenuated A20 expression of acute myeloid leukemia-derived dendritic cells increased the anti-leukemia immune response of autologous cytolytic T cells

Previous studies reported leukemic cells from acute myeloid leukemia (AML) patients can differentiate into dendritic cells (DCs), which had some immunoregulatory dysfunctions to effectively stimulate autologous CTLs’ anti-leukemia immune response. The zinc-finger protein A20, a negative regulator of the nuclear factor (NF)-κB pathway, was found to play a crucial role in controlling the maturation and function of human monocyte-derived DCs. However, the effects of A20 in AML derived DCs (AML-DCs) have not yet been evaluated. In this study, A20 expression was up-regulated in AML-DCs activated with tumor necrosis factor (TNF)-α. Then, A20 attenuation with siRNA in AML-DC enhanced the expression of several co-stimulatory molecules and proinflammatory cytokines. Furthermore, after A20 attenuation in AML-DCs, the autologous cytolytic T cells (CTLs) induced by AML-DCs had higher killing capability and specificity for primary AML cells. Additionally, receptor-interacting protein (RIP) and the NF-κBp65 pathway were elevated in AML-DCs when A20 was reduced. Hence, this study identified A20 as a negative regulator for controlling AML-DC maturation and immunostimulatory potency, as A20 down-regulation resulted in AML-DCs with enhanced autologous CTLs immune capacity through the NF-κB pathway.     

The expression of platelet-derived endothelial cell growth factor in human bladder cancer

Platelet-derived endothelial cell growth factor (PD-ECGF) is an angiogenic factor and in some studies PD-ECGF/dTdRPase expression levels in several kind of cancers were higher than in their surrounding normal tissues. In this study, we evaluated PD-ECGF/dTdRPase expression in bladder cancer by an immunohistological method and determined whether it correlated with tumor stage, grade and recurrence. PD-ECGF/dTdRPase expression was correlated with tumor grade and stage. Furthermore, among the superficial tumors, PD-ECGF/dTdRPase expression was correlated with a recurrence-free rate and thus it might be a prognostic factor for the recurrence of superficial bladder cancer.     

mir-27a、mir-200c及mir-145对肾癌细胞侵袭能力的影响

目的：探讨microRNA的表达在两种人肾癌细胞侵袭能力中的差异,为研究肾癌转移机制提供线索。方法：Transwell小室法检测两种人肾透明细胞癌细胞786-0、Caki-1侵袭能力差异。Real-time quantitativePCR方法检测两种细胞中mir-27a、mir-200c、mir-145表达水平。建立786-0及Caki-1细胞的裸鼠移植瘤模型,检测裸鼠786-0及Caki-1细胞移植瘤中mir-27a、mir-200c、mir-145可能调控的相应下游细胞黏附分子CD44、E-cadherin、β-catenin表达水平。结果：786-0细胞穿过Transwell小室的微孔膜的细胞数（196.8±4.9）明显高于Caki-1细胞（166.8±7.1）。786-0细胞中mir-27a、mir-200c、mir-145表达较Caki-1细胞明显升高。观察8周,786-0及Caki-1细胞在5×106/只的细胞数量下成瘤率为100%。CD44在裸鼠786-0细胞移植瘤中表达明显高于裸鼠Caki-1细胞移植瘤,β-catenin、E-cadherin在两种细胞裸鼠移植瘤中表达无明显差异。结论：mir-27a可能通过影响下游细胞黏附分子CD44的表达,影响肾癌细胞的侵袭能力,而mir-200c和mir-145影响肾癌侵袭能力的途径尚有待研究。     

小鼠AFPcDNA真核表达载体的构建、表达及体外抗肝癌免疫活性的检测

背景与目的:探索肝癌细胞的突变基因产物——具有潜在抗原性的异常蛋白质而无法形成有效免疫原的机理,寻找肝癌的特异性抗原,并在此基础上研制出治疗肝癌的DNA疫苗将对肝癌的免疫学治疗产生积极的影响。本实验构建BALB/c小鼠具有分泌性信号肽的AFP1cDNA和去掉信号肽的AFP2cDNA真核表达载体,分别在小鼠树突细胞(dendriticcells,DCs)中表达,并观察其在体外抗肝癌免疫中的作用。方法:采用RT-PCR方法自小鼠肝癌细胞株H22中扩增出具有分泌性信号肽的AFP1cDNA和去掉分泌性信号肽的AFP2cDNA,将该基因定向插入真核表达载体PEGF-N3中;同时培养经rmGM-CSF、rmIL-4诱导的小鼠骨髓细胞,体外获取大量DCs,脂质体转染PEGF-N3/AFP1、PEGF-N3/AFP2至DCs进行表达、鉴定。将DCs疫苗与同源小鼠脾淋巴细胞混合培养,ELISA方法测定脾细胞γ-干扰素(IFN-γ)分泌活性,51Cr释放法测定脾淋巴细胞的特异性杀伤活性。结果:从H22中克隆到AFP1cDNA和AFP2cDNA,经测序完全正确,所构建的真核表达质粒PEGF-N3/AFP1和PEGF-N3/AFP2在小鼠DCs中获得稳定高效表达,其中PEGF-N3/AFP2明显刺激T细胞增殖,刺激指数(SI)为5.12±1.46,明显高于空质粒组(1.42±0.73)。AFP2/DC疫苗对H22细胞的特异性杀伤活性[(88.15±16.47)%]明显高于空质粒组[(12.72±5.45)%]。结论:成功地构建了真核表达载体PEGF-N3/AFP1和PEGF-N3/AFP2,编码去掉分泌性信号肽的PEGF-N3/AFP2转染的DC,能够诱导较强的特异性抗肝癌免疫效应。其机制可能为诱导肝癌细胞凋亡。     

miRNA21对人肺癌 A549细胞增殖及迁移的影响

目的：探讨抑制 miRNA21对人肺癌 A549细胞体外增殖、迁移及凋亡的影响。方法：采用体外转染法将 miRNA21－5p 瞬时转染 A549细胞后,应用 Real －time PCR 特异探针法检测人肺癌细胞系中 miRNA21的表达情况;应用 MTT 法检测人肺癌 A549细胞的增殖情况;应用 Transwell 小室检测人肺癌 A549细胞的迁移情况;流式细胞术（flow cytometry,FCM）检测细胞的凋亡情况;Western blot 检测人肺癌 A549细胞中表皮因子生长受体（epidermal growth factor receptor,EGFR）的表达。结果：与正常对照组和 miRNA21－NC 阴性对照组相比,miRNA21－5p 转染组人肺癌 A549细胞中 miRNA21表达水平显著降低,EGFR 表达显著下调,细胞生长显著受抑制,且促进人肺癌 A549细胞的凋亡（P ＜0．05）。结论：抑制 miRNA21在人肺癌 A549细胞中的表达,能够抑制 A549细胞的生长,促进其凋亡,miRNA21有可能作为治疗肺癌的新靶标之一。