乳腺癌及良性乳腺组织p185和p16蛋白表达的免疫组织化学研究

应用免疫组化S P法检测了 37例良性乳腺组织 (非上皮增生组 17例、上皮增生组 2 0例 )和 5 9例乳腺癌组织中癌基因蛋白 p185和抑癌基因 p16蛋白的表达状况。结果显示非上皮增生组、上皮增生组和癌的p185阳性率分别为 0 %、15 %和 47%(p <0 0 1) ;p16阳性率分别为 41%、30 %和 34%。p185和p16的表达无明显相关性。乳腺癌早期的 p185过表达和p16失表达率高于浸润性导管癌。两者的阳性率均随组织学级别的增高和瘤体的增大而呈上升趋势 ,但 p >0 0 5。淋巴结转移组的p185阳性率 ( 6 4%)明显高于无淋巴结转移者 ( 32 %) ,p <0 0 5。表明 p185过表达和p16失表达在乳腺癌的发生发展中各自发挥独立的作用。p185是乳腺癌重要的肿瘤标志物。     

富含二硫键的膜蛋白p185胞外区在大肠杆菌中的可溶性表达和性质鉴定

Her2/c-erbB-2基因（其产物为膜蛋白p185）是表皮生长因子受体（EGFR）基因家族的一员,在约30％的乳腺癌中发现了其过量表达。为了鉴定抗p185单克隆抗体的抗原表位并进一步研究它们的相互作用,采用PCR的方法从含Her2/c_erbB_2基因的pBabe/erbB_2质粒中扩增了p185胞外区的富含二硫键的第一、二结构域和第四个结构域。产物克隆到pGEX/4T-1载体后,转化大肠杆菌Origami B（DE3）pLysS菌株,用低浓度IPTG进行低温过夜诱导后将菌体压力破碎,SDS-PAGE检测表达上清,得到了可溶性表达的融合有GST的目的蛋白。经ELISA、Western blot等方法鉴定,可溶性表达产物具有完全的抗体结合活性,且当用凝血酶把GST切掉后该活性仍然保留。P185胞外区融合蛋白的成功表达将为二硫键富含类蛋白的表达提供参考;并为将来具有肿瘤细胞生长抑制活性的抗p185单克隆抗体的抗原表位鉴定,以及为EGFR家族受体的结构和功能关系的研究打下基础。     

Numb在三阴乳腺癌中抑制HDM2泛素化降解p53

目的:探究Numb蛋白在三阴乳腺癌患者中的表达降低情况,及Numb蛋白在三阴乳腺癌中对抑癌因子p53蛋白水平的影响及调控机制,进一步研究Numb蛋白的降低与三阴乳腺癌发生发展的相关性,从而为缺乏有效治疗方法的三阴乳腺癌提供一个潜在的治疗新靶点。方法:40例三阴乳腺癌患者病理组织切片取自重庆医科大学临床病理诊断中心,采用免疫组化法检测Numb蛋白在三阴乳腺癌患者中的表达情况。MCF-10A细胞株和MDA-MB-231细胞株均为ATCC来源,采用qPCR和Western blot法检测对比Numb、HDM2、p53三者的转录水平和蛋白质水平在以上两个细胞株中差异。采用增强型绿色荧光蛋白(enhance green fluorescent protein,EGFP)质粒转染的方法在MDA-MB-231细胞中重表达Numb,采用q PCR和Western blot法验证Numb、HDM2、p53三者表达的变化。结果:转染NUMB-EGFP后MDA-MB-231细胞中Numb的mRNA和蛋白质水平均明显上调,HDM2无显著改变,p53在转录水平无明显变化,但在蛋白质水平显著升高。在231细胞中上调Numb蛋白可以在转录后水平调节p53水平,使p53蛋白随之显著升高。结论:Numb蛋白在三阴乳腺癌患者中表达降低的比列很高,为55%,且Numb蛋白在三阴乳腺癌细胞MDA-MB-231中可以调控抑癌因子p53蛋白水平,Numb蛋白水平与p53蛋白水平呈正相关。     

乳腺癌细胞肿瘤标记物表达及其与临床病理特征相关性研究

目的 探讨肿瘤标记物14-3-3σ、Akt 和p27Kip1 蛋白在乳腺癌中的表达及其与临床病理特征及Her-2 的相关性.方法 选取43 份乳腺癌石蜡标本和10 份正常乳腺组织标本,采用免疫组织化学技术(SABC)检测组织中14-3-3σ、Akt 和p27Kip1 蛋白的表达,结合临床资料和随访资料,进行回顾性研究,...     

量子点免疫荧光技术在病理诊断中的初步应用

目的利用量子点(quantum dots,QDs)免疫荧光技术检测石蜡包埋组织中不同蛋白的定位与免疫酶法进行比较,以及两种蛋白的共表达,并探讨其初步应用价值。方法利用QDs免疫荧光和免疫酶组织化学方法分别检测正常阑尾组织LCA、乳腺肌上皮组织Calponin、肺癌组织p53蛋白的表达,并利用QDs免疫荧光双标法同时检测了宫颈上皮内瘤变组织内CK和PCNA蛋白、乳腺癌组织内Her-2和CK蛋白的共表达。结果QDs免疫荧光和免疫酶组织化学技术分别检测LCA、Calponin和p53蛋白的定位完全一致。QDs免疫荧光双标法结合多光谱成像可同时观察到宫颈上皮内瘤变组织内CK和PCNA蛋白、乳腺癌组织内Her-2和CK蛋白的共表达。结论QDs免疫荧光组织化学法具有与免疫酶法等同的应用价值。QDs免疫荧光双标法可同时检测不同蛋白的共定位。     

乳腺癌细胞中p27kip1分子相互作用蛋白质谱的改变

p27kipl是细胞周期重要的负性调控因子,在乳腺癌等多种肿瘤发生发展过程中发挥重要作用.乳腺癌细胞中p27kipl蛋白通常是低丰度表达和错位分布,导致这种分布和表达改变的确切机制并不明确.已有研究表明,p27kipl磷酸化是重要的调节途径之一,细胞内外信号分子通过多种途径调节p27kipl的分布和表达.为了进一步阐明肿瘤细胞内调节p27kipl功能的分子机制,必须首先明确p27kipl在肿瘤细胞与正常细胞中相互作用蛋白质谱的差异.包括细胞周期素、周期素依赖性激酶、CRM1、jab1、Skp2等在内的多种分子可以与p27kipl发生相互作用.在乳腺癌细胞中还有儿种特异的作用分子.在不同细胞周期和不同细胞内分布状态下,p27kipl蛋白有不同的相互作用蛋白质谱.因此,我们推断在乳腺癌细胞内p27kipl分子相互作用蛋白质谱的差异可能是导致其低表达和错位分布的主要机制.     

基质金属蛋白酶-2和p185HER-2/neu蛋白在卵巢癌中的研究进展

基质金属蛋白酶-2(Matrix Metalloproteinase-2,MMP-2)是基质金属蛋白酶家族的重要成员,能降解明胶蛋白和Ⅳ型、V型胶原,在细胞外基质的降解过程中起着关键作用,能够促进肿瘤细胞发生侵袭和转移。p185HER-2/neu蛋白是一种相对分子质量185×103的跨膜糖蛋白,由HER-2/neu基因编码,属于酪氨酸激酶受体家族,p185HER-2/neu蛋白在人类多种癌症中存在扩增及过量表达,并与肿瘤的侵袭性表型及生存期短密切相关。就基质金属蛋白酶-2和p185HER-2/neu蛋白的生物学特性,与卵巢癌侵袭转移和预后的关系及MMP-2和p185HER-2/neu蛋白的研究情况等予以综述。     

p53在乳腺癌中的作用

乳腺癌是一种世界范围内女性发病率较高的肿瘤之一,至今为止对其的诊断、病理机制、治疗及预后已有一定的了解.一部分科学家的对乳腺癌的研究主要集中在p53在其发病机理、治疗、预后中的作用的探讨.p53是目前被广泛关注的肿瘤抑制基因,它所编码的转录蛋白因子主要调节一系列与细胞周期抑制、衰老、凋亡、DNA的修复、新血管生成的反应相关的基因.主要就近几年对乳腺癌的研究中,p53基因在乳腺癌中的作用机制的进一步研究,p53做为分子标记在诊断和预后的意义,它的突变和等位基因的性质,以及以p53为基础的各种治疗手段中其与药物及其他基因最新的作用机制进行初步的阐述.     

过表达P185可抑制EMT并促进胃癌细胞侵袭和迁移

为探究过表达P185基因对胃癌SGC7901细胞侵袭、迁移的影响以及可能作用机制,本研究通过脂质体将携带P185基因的过表达pcDNA3.1-P185质粒,转染至胃癌SGC7901细胞中;本研究采用qRT-PCR和免疫印迹试验(Western blotting)检测P185 mRNA的转录水平和蛋白水平,Western blotting检测钙黏蛋白E(E-cadherin)、波形蛋白(Vimentin)、基质金属蛋白酶-2 (matrix metalloprotease, MMP-2)表达;以Transwell小室法检测细胞的侵袭、迁移能力的变化。研究结果表明:胃癌细胞转染过表达pcDNA3.1-P185质粒能显著上调P185 mRNA和蛋白质的表达(p0.05);SGC7901细胞转染重组质粒pcDNA3.1-P185后,细胞的侵袭、迁移能力较对照组显著增强(p0.05),细胞中E-cadherin蛋白水平显著下调(p0.05),Vimentin、MMP-2蛋白水平显著增加(p0.05)。本研究显示P185可能通过抑制EMT,促进细胞外基质的降解、促进胃癌细胞的侵袭、迁移。     

EGCG经AKT1-Mdm-2-p53途径抑制卵巢癌HO-891O细胞的增殖

初步探讨EGCG对卵巢癌HO-8910细胞增殖的抑制作用及其机制.方法:通过绘制细胞生长曲线、平皿克隆和软琼脂集落形成实验观察EGCG对HO-8910细胞增殖的抑制作用;Western-blotting检测AKT1、Mdm-2与p53蛋白的表达.结果:(1)细胞生长曲线、平皿克隆和软琼脂集落形成实验结果显示,EGCG可有效抑制HO-8910细胞的增殖(n=3,P＜0.05).(2)Westemblotting检测结果显示,EGCG处理后AKT1与Mdm-2蛋白表达均降低,而p53蛋白表达升高(P＜0.05).结论:EGCG通过抑制HO-8910细胞中AKT1与Mdm-2蛋白表达,促使p53蛋白表达而发挥其对细胞增殖的抑制作用.     

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.     

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     

Comparative morphology of the carpel in the Liliaceae: Hewardieae, Petrosavieae, and Tricyrteae

The young pistils in the melanthioid tribes, Hewardieae, Petrosavieae and Tricyrteae, are uniformly tricarpellate and syncarpous. They lack raphide idioblasts. All are multiovulate, with bitegmic ovules. The Petrosavieae are marked by the presence of septal glands and incomplete syncarpy. Tepals and stamens adhere to the ovary in the Hewardieae and the Petrosavieae but not in the Tricyrteae. Two vascular bundles occur in the stamens of the Hewartlieae and Tricyrtis latifolia. Ventral bundles in the upper part of the ovary of the Hewardieae are continuous with compound septal bundles and placental bundles in the lower part. Putative ventral bundles occur in the alternate position in the Tricyrteae and putative placental bundles in the opposite. position in the Petrosavieae. The dichtomously branched stigma in each carpel of the Tricyrteae is supplied by a bifurcated dorsal bundle.     

Entwicklungsgeschichte und Ultrastruktur von Pollenkitt und Exine bei nahe verwandten entomophilen und anemophilen Angiospermensippen derAlismataceae,Liliaceae, Juncaceae,Cyperaceae, Poaceae undAraceae

Some closely related members of the monocotyledonous familiesAlismataceae, Liliaceae, Juncaceae, Cyperaceae, Poaceae andAraceae with variable modes of pollination (insect- and wind-pollination) were studied in relation to the ultrastructure of pollenkitt and exine (amount, consistency and distribution of pollenkitt on the surface of pollen grains). The character syndromes of pollen cementing in entomophilous, anemophilous and intermediate (ambophilous or amphiphilous) monocotyledons are the same in principal as in dicotyledons. Comparing present with former results one can summarize: 1) The pollenkitt is always produced in the same manner by the anther tapetum in all angiosperm sub-classes. 2) The variable stickiness of entomophilous and anemophilous pollen always depends on the particular distribution and consistency of the pollenkitt, but not its amount on the pollen surface. 3) The mostly dry and powdery pollen of anemophilous plants always contains a variable amount of inactive pollenkitt in its exine cavities. 4) A step-by step change of the pollen cementing syndrome can be observed from entomophily towards anemophily. 5) From the omnipresence of pollenkitt in all wind-pollinated angiosperms studied one can conclude that the ancestors of anemophilous angiosperms probably have been zoophilous (i.e. entomophilous) throughout.

     

Identification and Characterization of the First Equine Parainfluenza Virus 5

正Dear Editor,Parainfluenza virus 5 (PIV5), known as canine parainfluenza virus in the veterinary field, is a negative-sense,nonsegmented, single-stranded RNA virus belonging to the Paramyxoviridae family (Chen 2018). The virus was first reported in primary monkey kidney cells in 1954 (Hsiung1972), then it has been frequently discovered in various