lncRNA BLACAT1通过抑制miR-374b-5p促进非小细胞肺癌细胞增殖和转移

目的:研究长链非编码RNA BLACAT1在非小细胞肺癌发生和转移过程中的作用机制。方法:starBase软件分析TCGA数据库中肺腺癌及肺鳞癌与癌旁组织之间BLACAT1表达差异;qRT-PCR检测人非小细胞肺癌细胞A549、HCC827、NCI-H1299、NCI-H23和正常肺上皮细胞BEAS-2B中BLACAT1的转录水平差异,筛选BLACAT1高表达非小细胞肺癌细胞系;CCK-8检测BLACAT1对非小细胞肺癌细胞增殖能力的影响;Transwell检测BLACAT1对非小细胞肺癌细胞迁移和侵袭能力的影响;starBase软件预测BLACAT1作用的miRNA,采用qRT-PCR验证敲低BLACAT1对预测miRNA表达的影响,筛选与BLACAT1相互作用的miRNA,双萤光素酶报告基因实验验证结果;CCK-8检测BLACAT1/miR-374b-5p对非小细胞肺癌细胞增殖能力的影响;Transwell检测BLACAT1/miR-374b-5p对非小细胞肺癌细胞迁移和侵袭能力的影响;Western印迹检测非小细胞肺癌细胞转移相关基因的蛋白表达水平。结果:肺腺癌及肺鳞癌组织中BLACAT1表达量显著高于癌旁组织;非小细胞肺癌细胞A549的BLACAT1表达量最高;敲低BLACAT1降低A549细胞活力、迁移和侵袭能力;BLACAT1作为海绵吸附miR-374b-5p;敲低BLACAT1增加miR-374b-5p的表达,抑制非小细胞肺癌细胞增殖、迁移和侵袭。结论:BLACAT1通过抑制miR-374b-5p促进非小细胞肺癌细胞增殖和转移。     

埃兹蛋白的表达与非小细胞肺癌转移的关系研究

目的:探究埃兹蛋白(Ezrin)的表达与非小细胞肺癌转移的关系。方法:通过免疫组化检测Ezrin在有无转移的非小细胞肺癌组织中的表达差异,通过细胞免疫组化、western-blot、RT-PCR检测Ezrin在不同转移潜能肺癌细胞系中的表达差异,通过transwell考察Ezrin对不同转移潜能癌细胞侵袭和迁移能力的影响。结果:Ezrin蛋白在有转移的非小细胞肺癌组织中的表达水平明显高于无转移的肺癌组织,在高转移潜能肺癌细胞系中的表达高于低转移潜能细胞系,受抑制时会削弱高转移潜能肺癌细胞的迁移和侵袭能力,过表达时会增强低转移潜能肺癌细胞的侵袭和迁移能力。结论:Ezrin可能在非小细胞肺癌及其转移中发挥重要作用。     

MicroRNA-575靶向抑制BLID促进非小细胞肺癌细胞的增殖和侵袭

目的:通过体外实验探讨miR-575对非小细胞肺癌(NSCLC)细胞增殖与侵袭能力的影响及相关机制。方法:采用实时定量PCR法检测不同非小细胞肺癌细胞系中miR-575、BLID的表达;CCK-8法检测转染miR-575模拟物、抑制因子后不同时间A549细胞增殖情况的变化;Transwell法检测A549细胞的侵袭情况;Targetcan法及双荧光素酶检测miR-575对BLID 3'UTR端的靶向作用;Western blot法检测BLID蛋白的表达。结果:A549、SPC-A1、H1299、H1650等人非小细胞肺癌细胞系中miR-575的表达均显著高于永生化的人支气管上皮细胞系16HBE(P0.001)。MiR-575模拟物转染的A549细胞miR-575的表达明显高于对照组(P0.001),同时细胞的增殖和侵袭力增强(P0.05);反之,miR-575抑制因子转染的A549细胞miR-575的表达显著降低,且细胞的增殖和侵袭力明显降低(P0.01)。Targetscan法预测BLID可能是miR-575的下游靶基因,荧光素酶结果显示miR-575不仅能够有效抑制野生型BLID 3'UTR端的荧光素酶反应(P0.01),而且能够降低BLID的蛋白表达量(P0.01)。实时定量PCR结果显示BLID在NSCLC细胞系中均呈现显著的低表达(P0.001),且转染BLID后,NSCLC细胞的增殖和细胞侵袭被明显抑制(P0.05),而当miR-575与BLID共转染时,miR-575能够逆转BLID所抑制的细胞增殖和侵袭(P0.01)。结论:在NSCLC细胞系中,miR-575的表达上调,且能够通过直接作用于下游靶点抑癌基因BLID从而促非小细胞肺癌细胞增殖及侵袭。     

miR-223促进人胃癌MGC-803细胞增殖的研究

目的:探讨miR-223的表达与胃癌细胞的增殖能力的关系.方法:采用实时定量PCR检测人胃癌组织及细胞系中miR-223的表达.采用四甲基偶氮唑蓝(MTT)法和克隆形成实验测定转染miR-223 inhibitors前后的胃癌细胞增殖的变化.结果:相对于正常胃粘膜组织及细胞,在胃癌组织和细胞中miR-223的表达水平出现了显著的上调,MGC-803细胞中转染miR-223 inhibitors能显著抑制miR-223的表达水平.抑制miR-223能降低胃癌细胞的增殖能力.结论:miR-223对胃癌细胞增殖的调控至关重要.miR-223的表达降低能显著抑制胃癌细胞的增殖能力.     

微堆发酵普洱茶对人非小细胞肺癌的抑制作用研究

目的：探索微堆发酵法制造的普洱茶对人肺NCI-H1299细胞的影响,为肺癌的预防及辅助治疗提供科学依据。方法：采用微堆发酵法生产普洱茶,并将其提取液作用于人肺NCI-H1299细胞,采用WST-1 细胞增殖及细胞毒性检测试剂盒检测H1299细胞的增殖情况、采用细胞划痕愈合法检测H1299细胞的迁移情况、采用Transwell细胞体外侵袭实验法检测H1299细胞的侵袭能力。结果：微堆发酵法生产出的普洱茶符合国家标准;该普洱茶提取液能有效抑制NCI-H1299细胞的增殖（P<0.01）、迁移（P<0.01）与侵袭（P<0.05）,且呈浓度依赖性。结论：微堆发酵法生产的普洱茶能够抑制人非小细胞肺癌H1299的增殖、迁移和侵袭。     

GINS2基因对非小细胞肺癌的作用及功能分析

GINS2在多种侵袭性肿瘤中上调,然而,其在非小细胞肺癌(NSCLC)中的作用及功能仍有待阐明.本研究主要对GINS2在非小细胞肺癌中的作用及功能进行分析,通过肿瘤基因组图谱(TCGA)数据库分析发现,GINS2在NSCLC中显著上调.为了研究GINS2在NSCLC细胞中的作用及其功能,首先,采用小干扰RNA技术设计了该基因的siRNA,以此来沉默GINS2的mRNA,细胞水平转染后,该基因在非小细胞肺癌细胞系NCI-H292和A549中的表达降低;随后,采用实时细胞分析仪(real time cell analyzer,RTCA)和Tran-swell小室实验对细胞的增殖、迁移和侵袭进行测定,最后采用流式细胞仪分析细胞的周期以及细胞凋亡.实验结果显示:在NCI-H292和A549两个细胞系中,用siRNA沉默GINS2的表达后,NCI-H292和A549细胞的生长能力、迁移能力和侵袭能力均会受到明显的抑制;此外,细胞的周期凋亡实验显示,在NCI-H292细胞系中,阻碍了细胞G1期向S期的转变;在A549细胞系中,阻碍了细胞S期向G2期的转变,同时在两个细胞系中均表现出促进细胞凋亡等功能.综上所述,敲低GINS2可抑制NCI-H292和A549细胞的增殖、迁移和侵袭,并且能阻滞细胞周期促进细胞凋亡等.因此,研究该基因在NSCLC中的功能对于后续研究分子机制具有很大的意义,可能是未来的特异性治疗靶点.     

IscU2对非小细胞肺癌增殖、迁移、侵袭能力的影响及其作用机制的研究

该文通过shRNA干扰技术敲低IscU2干扰细胞IscU2的表达,研究了干扰IscU2对非小细胞肺癌(NSCLC)细胞NCI-H520增殖、迁移及侵袭能力的影响。构建了稳定低表达IscU2的非小细胞肺癌细胞系NCI-H520;采用CCK-8和平板克隆实验检测细胞的增殖能力;流式细胞仪检测细胞周期、凋亡、ROS、线粒体膜电位变化情况;Transwell实验检测细胞迁移及侵袭能力;Western blot检测相关蛋白的表达。结果表明,干扰IscU2后,非小细胞肺癌细胞的增殖及克隆形成能力降低;细胞周期停滞在G1/G0期,同时伴随有p-AKT和Cyclin D1蛋白含量的下降;细胞晚期凋亡率明显增加,凋亡蛋白Cleaved-caspase3和Cleaved-PARP表达上调;细胞迁移和侵袭能力降低,上皮标志物E-Cadherin表达上调,间质标志物N-Cadherin和Snail表达下调;细胞ROS积累和线粒体膜电位下降。该研究结果表明,干扰IscU2显著抑制非小细胞肺癌的增殖、迁移、侵袭能力和上皮–间质转化,这为非小细胞肺癌的诊断和治疗提供了新的潜在靶点和视角。     

miRNA-21靶向调控Wnt/β-catenin对非小细胞肺癌细胞增殖与侵袭的影响

目的研究microRNA-21(miR-21)是否通过调控wnt/β-catenin信号通路从而影响人非小细胞肺癌(non-small cell lung cancer, NSCLC)细胞株NCI-H1975细胞体外增殖与侵袭能力。方法预测和构建含有miR-21候选靶基因和β-连环蛋白基因的双荧光素酶报告质粒。将miR-21模拟物通过Lipofactamine 2000脂质体转染法转染NCI-H1975细胞,应用qRTPCR检测细胞中miR-21和β-catenin mRNA表达情况,应用Western blot检测β-catenin蛋白水平,CCK-8法检测miR-21mimic对NCI-H1975细胞增殖能力的影响,Transwell侵袭实验检测miR-21 mimic对NCI-H1975细胞侵袭能力的影响。结果qRT-PCR肺癌组织中的miR-21与邻近正常组织相比表达明显升高;双荧光素酶报告基因结果显示miR-21能和β-catenin的3’UTR端结合且显著促进荧光素酶活性;上调miR-21可使β-catenin的mRNA和蛋白表达水平显著升高,同时上调miR-21可显著增强NCI-H1975细胞的增殖与侵袭能力。结论 miR-21在转录后水平调控β-catenin表达来促进NCI-H1975细胞的增殖与侵袭能力,可能是NSCLC潜在的治疗靶点。     

miR-29a靶向调控PDGFB促进非小细胞肺癌细胞凋亡

为了探究miR-29a对非小细胞肺癌细胞增殖和凋亡的影响及分子机制,本研究通过荧光定量PCR检测肺癌组织、癌旁组织、肺癌细胞以及人正常肺支气管上皮细胞BEAS-2B中miR-29a的表达,在肺癌A549转染miR-29a mimics后,使用荧光定量PCR和CCK-8法分别检测miR-29a的表达以及各组细胞的活力,使用流式细胞术检测A549细胞凋亡;通过荧光定量PCR检测肺癌组织、癌旁组织PDGFB m RNA的表达,采用Western blot检测PDGFB蛋白的表达;使用双荧光素酶报告基因检测miR-29a可能的靶基因;在肺癌A549细胞转染miR-29a mimics后继续转染PDGFB过表达质粒,通过qPCR和Western blotting分别检测PDGFB mRNA和蛋白的表达。结果表明,与癌旁组织相比,miR-29a在肺癌组织的表达显著下调(p<0.01),PDGFB在肺癌组织的表达显著增加(p<0.01);转染miR-29a mimics后,肺癌A549细胞中miR-29a表达显著增加(p<0.01);CCK-8法结果显示miR-29a mimics组A549肺癌细胞在24 h和48 h后细胞增值率较miR-NC对照组显著降低(p<0.01);流式细胞术结果显示miR-29a mimics组的细胞凋亡率较miR-NC对照组显著增加(p<0.01);与miR-NC+PDGFB 3’UTR WT组相比,miR-29a mimics+PDGFB 3’UTR WT组的荧光强度显著降低(p<0.01);荧光定量PCR和Western blotting显示miR-29a mimics+PDGFB组PDGFB m RNA和蛋白表达量与miR-29a mimics+vector组相比显著增加(p<0.01)。本研究结果表明miR-29a在肺癌组织和肺癌细胞株中低表达,及抑制PDGFB的表达并且促进肺癌细胞凋亡。     

miR-204通过抑制OGT的表达调控非小细胞肺癌细胞的增殖和迁移

目的:探究miR-204和O-连接N-乙酰氨基葡萄糖转移酶(O link N-acetylglucosamine transferase,OGT)对非小细胞肺癌(Non-small cell lung cancer,NSCLC)细胞增殖和转移的影响,并深入分析其可能机制。方法:采用Oncomine及KM-Ploter数据库分析OGT在肺癌组织中的表达及与肺癌患者预后的关系;采用慢病毒转染人非小细胞肺癌A549及永生化人肺支气管上皮细胞BEAS-2B,分别构建OGT稳定下调和过表达的细胞系,利用CCK-8、平板克隆和裸鼠皮下成瘤实验检测细胞增殖的情况,划痕实验、Transwell实验和裸鼠尾静脉注射肺转移模型检测细胞转移的情况。利用数据库分析可能参与OGT调控的microRNA,并用双荧光素酶报告基因验证。利用TCGA数据库分析miR-204在肺癌中的表达情况,并在30例肺癌组织及其对应癌旁组织中分析miR-204与OGT之间的相关性。结果:OGT在肺癌组织中呈高表达,且与患者的不良预后相关(HR=1.22,P 0.01);OGT的表达上调肺癌细胞的增殖和转移;miR-204可以负向调控OGT的表达,且miR-204在肺癌组织中表达水平显著低于癌旁组织,在肺癌组织中miR-204的水平与OGT的表达水平呈负相关(R~2=-0.4729,P 0.01)。结论:在非小细胞肺癌中,miR-204的降低通过上调OGT的表达促进肺癌的增殖和转移。     

Recent advances in the study of Kaposi's sarcoma-associated herpesvirus replication and pathogenesis

It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.     

A Unique Protease Cleavage Site Predicted in the Spike Protein of the Novel Pneumonia Coronavirus (2019-nCoV) Potentially Related to Viral Transmissibility

正Dear Editor,In December 2019, a novel human coronavirus caused an epidemic of severe pneumonia(Coronavirus Disease 2019,COVID-19) in Wuhan, Hubei, China(Wu et al. 2020; Zhu et al. 2020). So far, this virus has spread to all areas of China and even to other countries. The epidemic has caused 67,102 confirmed infections with 1526 fatal cases     

Curcuminoids as inhibitors of thioredoxin reductase: A receptor based pharmacophore study with distance mapping of the active site

Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.     

The structure, reproduction and taxonomy of Vidalia and Osmundaria (Rhodophyta, Rhodomelaceae)

Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.     

New or rare chromosome counts in Artemisia L. (Asteraceae, Anthemideae) and related genera from Kazakhstan

Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.