飞行质谱法对大肠癌LoVo及HT29细胞悬液中蛋白质的比较研究

目的对LoVo细胞、HT29细胞培养液中蛋白质进行对比研究。方法应用美国CipherGen公司IMAC3(金属亲和表面)芯片和蛋白质芯片仪检测LoVo细胞与HT29细胞培养液。结果LoVo细胞、HT29细胞培养液中都含有质荷比为2812D、14873D的蛋白质。结论LoVo细胞与HT29细胞培养液含有上述相同的蛋白质,即LoVo细胞悬液与大肠癌血清的生物标志物间存在相似性;但其他蛋白质差别则比较大。     

裂解液对变异链球菌蛋白质提取效果的影响

目的探讨裂解液对变异链球菌蛋白质提取效果的影响。方法通过革兰染色、SDS-PAGE和蛋白质浓度测定,对4种裂解液提取变异链球菌蛋白质的效果进行评价。结果裂解液Ⅲ、Ⅳ中的细菌破碎程度高于裂解液Ⅰ、Ⅱ。裂解液Ⅱ提取的蛋白质条带丰度低于其他3种裂解液。裂解液Ⅲ、Ⅳ提取的蛋白浓度高于裂解液Ⅰ、Ⅱ(P<0.05)。结论含还原剂、去垢剂、离液剂和蛋白酶抑制剂的裂解液提取变异链球菌蛋白质的效果优于只含还原剂和去垢剂的裂解液。     

不同细胞裂解液对肝细胞蛋白提取影响的研究

目的　寻找一种更适合肝细胞蛋白质提取的细胞裂解液配方。方法　配制不同组成和不同浓度的细胞裂解液 ,分别对相同条件下培养的肝细胞进行裂解并进行蛋白定量及十二烷基磺酸钠 聚丙烯酰胺凝胶电泳 (SDS PAGE)佐证。结果　不同组成及不同浓度的细胞裂解液对肝细胞裂解作用存在显著差异。结论　去污剂用 4 % 3 [(3 胆酰胺丙基 ) 二乙胺 ] 丙磺酸 (CHAPS)的细胞裂解液对肝细胞裂解效果最好。     

金线莲水提物给药前后肿瘤细胞蛋白质组的差异比较

目的:建立利用二维液相色谱法分离肿瘤细胞全细胞裂解液的分析方法,进而研究金线莲水提物的抗肿瘤作用以及肿瘤细胞蛋白质组的差异。方法:将金线莲水提物给药后的肿瘤细胞裂解样品及对照样品用初始缓冲液置换后,进行一维色谱聚焦分离,然后先对二维色谱条件进行优化和重复性分析,再将一维收集的pH4.0～8.5之间的组分分别进行二维无孔硅胶HPLC分离,利用ProteoVue软件将UV图转换成胶图,分析差异。结果:一维色谱聚焦分离pH4.0～8.5之间组分共收集到16个,每个组分的二维UV图转换成PI/UV胶图,结果表明金线莲水提物给药前后肿瘤细胞蛋白质组差异具显著性。结论:二维液相色谱分离法是一种有效的分离肿瘤细胞裂解液的方法,给药后的肿瘤细胞蛋白质组和对照相比差异具显著性。     

神经胶质瘤蛋白质双向电泳技术的建立

目的建立神经胶质瘤双向电泳技术。方法利用不同体积的裂解液提取大鼠脑组织中的蛋白质，并通过不同的蛋白质上样量（1、2、3mg），进行双向电泳，考马斯亮蓝染色，图谱分析。结果在等电点3-10，相对分子质量6．5-200KDa范围内分离得到蛋白质斑点为，1mg蛋白质上样量为574个蛋白质斑点，2mg为798个，3mg为803个斑点。2mg蛋白质上样量的双向电泳图谱更清晰，分离更好。结论成功建立了神经胶质瘤蛋白质的双向电泳技术。     

蛋白质芯片在药学中的应用蛋白质芯片在药学中的应用

随着生物芯片技术的发展，蛋白质芯片的制备和应用技术已获得突破性进展，不仅在蛋白质芯片制作方面引入机器人制作和商品化玻片载体，而且较成功的解决了蛋白质固相表面的固定问题，为蛋白质芯片的进一步发展奠定了基础。UetZ等使用酵母双杂交系统构建蛋白质芯片，首次把蛋白质     

谷氨酰胺对肿瘤生长和肝癌细胞凋亡的影响(英文)

目的:探索谷氨酰胺对肿瘤生长及肝癌细胞凋亡的影响。方法:在小鼠右腋皮下接种H22肿瘤细胞悬液,灌服含谷氨酰胺(GLN)液;在人肝癌细胞培养液中加入不同浓度的GLN液。分别检测小鼠血浆及细胞培养液中MDA、NO及细胞中GSH含量,观察小鼠右腋皮下肿瘤生长及肝癌细胞增殖和凋亡情况。结果:灌服GLN液,有抑制皮下肿瘤块生长的作用;在人肝癌细胞培养液中加入一定浓度的GLN液,有抑制肝癌细胞增殖的作用并促使肝癌细胞凋亡。同时小鼠血浆和细胞培养液中NO含量升高,MDA稍有下降;细胞粉碎液中,GSH升高。结论:GLN对肿瘤生长的抑制作用及对肝癌细胞凋亡的影响可能与使抗氧化活性的提高、阻抑自由基对癌细胞增殖的介导及促使NO释放有关。     

蛋白质芯片及其应用

目的大规模的基于组学和蛋白质组学的方法发现了大量的新蛋白质,这就给生命科学带来了新的挑战:高通量地研究这些蛋白质,并发现它们的功能。蛋白质芯片技术的发展,使得这一问题迎刃而解。此文就蛋白质芯片技术的原理、制备、探针标记、信号检测、数据处理、分类、芯片实验室、应用及存在的问题作出了阐述。     

生物芯片技术及其在医学中的应用

介绍生物芯片技术的概念、特点、原理、类型和在医学上的应用,着重介绍蛋白质芯片和组织芯片.蛋白质芯片可用于寻找疾病生物学标志物、研究蛋白质相互作用、药物或毒物新靶点及其作用机制等;组织芯片可用于基因表达分析、寻找与临床治疗及预后有关的标志物、发现新的侯选癌基因或抑癌基因等.     

生物芯片技术及其在医学上的应用

介绍生物芯片技术的概念、特点、原理、类型和在医学上的应用,着重介绍蛋白质芯片和组织芯片.蛋白质芯片可用于寻找疾病生物学标志物、研究蛋白质相互作用、药物或毒物新靶点及其作用机制等;组织芯片可用于基因表达分析、寻找与临床治疗及预后有关的标志物、发现新的侯选癌基因或抑癌基因等.     

蛋白激酶C在表没食子儿茶素没食子酸酯诱导LoVo细胞凋亡中的作用

目的　探讨蛋白激酶C在表没食子儿茶素没食子酸酯 (EGCG)诱导大肠癌LoVo细胞凋亡中的调控作用。方法　在有或没有蛋白激酶C激活剂PMA预处理LoVo细胞的情况下 ,用流式细胞术、Westernblot分析以及蛋白激酶C检测试剂盒检测EGCG处理LoVo细胞前后其细胞内多种蛋白激酶C同工酶表达水平和细胞内蛋白激酶C总活性的变化。结果　PMA(10 0nmol·L-1)预处理LoVo细胞 3h ,可部分地抑制EGCG诱导的LoVo细胞凋亡。流式细胞术和Westernblot分析显示EGCG处理LoVo细胞后可引起该细胞内多种蛋白激酶C同工酶包括cPKCα、βⅠ、βⅡ、nPKCε和aPKCξ表达水平下调 ,并呈时间效应关系 ;而细胞内蛋白激酶C总活性无明显变化。结论　蛋白激酶C参与了EGCG诱导LoVo细胞凋亡的调控作用 ,主要是通过下调多种蛋白激酶C同工酶表达水平而不是通过影响细胞内蛋白激酶C总活性而发挥作用     

三氧化二砷对人大肠癌LoVo细胞血管内皮生长因子表达的影响

目的 探讨血管内皮生长因子(VEGF)在人大肠癌细胞株LoVo中的表达及三氧化二砷(As2O3)对其表达的影响.方法 应用实时定量PCR法和免疫细胞化学法检测As2O3干预前后LoVo结肠癌细胞中VEGF mRNA及VEGF蛋白表达.结果 LoVo大肠癌细胞表达VEGF,VEGF基因表达与蛋白表达呈正相关,且VEGF表达随着As2O3剂量的增加而下降.结论 VEGF在人结肠癌细胞LoVo中表达,As2O3可显著抑制VEGF的表达,呈剂量依赖性,表明As2O3具有抑制肿瘤血管生成的作用.     

Plumbagin induces apoptosis,cell cycle arrest,and inhibits protein synthesis in LoVo colon cancer cells: A proteomic analysis

Extracted from the roots of Plumbago zeylanica L., plumbagin is a natural naphthoquinone with potential as an anticancer compound. However, no studies have investigated its impact on LoVo (colon cancer) cells, and the specific mechanisms by which plumbagin exerts its anticancer effects remain to be established. The anticancer potential of plumbagin against LoVo cells was evaluated using a battery of assays, including MTT assay, clone formation assay, transwell chamber invasion assay, and wound-curing assay. Cell cycle analysis and cell apoptosis analysis were conducted to break down the anticancer impact of plumbagin on LoVo cells. A label-free proteomics technology was employed to investigate alterations in protein expression in LoVo cells treated with plumbagin. Our investigation indicated that plumbagin markedly inhibited the LoVo cells proliferation, and induced the apoptosis in LoVo cells, simultaneously induced G0/G1 phase cell cycle arrest. The LC-MS/MS proteomics assay revealed 78 proteins that were differentially expressed upon treatment with plumbagin. Bioinformatics and functional analyses indicated that these proteins were predominantly involved in protein synthesis and translation. Our findings revealed that multiple mechanisms are involved in the anticancer activity of plumbagin against LoVo cells, resulting in decreased cell viability. Proteomic analysis suggests that plumbagin may impede protein synthesis by reducing the expression of eukaryotic initiation factors. Our findings demonstrate that plumbagin exerts its anticancer activity against LoVo cells through multiple mechanisms, including inhibition of cell proliferation, induction of apoptosis, cell cycle arrest, and disruption of protein synthesis. These results provide new insights into the therapeutic potential of plumbagin for colon cancer treatment.     

蝎毒抗癌多肽对大肠癌LoVo细胞的影响

目的探讨东亚钳蝎毒抗癌多肽对大肠癌LoVo细胞的影响及其与多种化疗药物的协同作用。方法采用MTT法(噻唑蓝比色试验)测定该抗癌多肽单独及与化疗药物协同对LoVo细胞的增殖抑制作用。结果蝎毒抗癌多肽可抑制LoVo细胞增殖,并且低浓度的蝎毒抗癌多肽与化疗药物协同,可产生较强的抑制细胞增殖的作用。结论蝎毒抗癌多肽具有直接的抗肿瘤作用,并且具有增强化疗药物作用的功效。     

全反式维甲酸提高人结肠癌LoVo细胞对奥沙利铂敏感性

目的探讨全反式维甲酸(all-trans retinoic acid,AT-RA)提高人结肠癌LoVo细胞对奥沙利铂的药物敏感性和机制。方法MTT法筛选ATRA和奥沙利铂实验浓度。流式细胞仪检测ATRA对细胞周期的影响。分别用ATRA、奥沙利铂、ATRA联合奥沙利铂作用LoVo细胞;MTT法检测药物抑制率,流式细胞仪检测细胞周期及凋亡率,原子光谱吸收仪检测细胞DNA含铂(Pt)量。结果奥沙利铂抑制LoVo细胞作用呈量效依赖;其GI50(GI,inhibit net cell growth by%)为6.5mg.L-1,主要阻滞肿瘤细胞在S期。ATRA抑制LoVo细胞作用呈时效和量效依赖。1.0μmol.L-1ATRA作用12h后G1期细胞增多;48h后伴S期、G2/M期细胞减少并明显抑制肿瘤细胞增殖;作用12h至48h后联合奥沙利铂,两药联合由相加作用转变为协同作用;联合用药后S期细胞明显增多,细胞DNA含Pt量明显增加,但不提高奥沙利铂凋亡率。结论小剂量ATRA通过改变LoVo细胞周期和提高细胞DNA含Pt量,明显增加肿瘤细胞对奥沙利铂的药物敏感性。     

Brucine,an effective natural compound derived from nux-vomica,induces G1 phase arrest and apoptosis in LoVo cells

Brucine is an alkaloid from nux vomica, has been shown various pharmacological actions. To study the possible anti-cancer mechanisms on LoVo cells, effects of Brucine on cell viability, cell cycle and apoptosis were investigated. The results showed that Brucine revealed strong growth inhibitory effect on LoVo cells, and caused LoVo cell shrinkage and membrane blobbing, induced cellular and DNA morphological changes. Cell cycle and apoptosis analysis documented that Brucine could change cell cycle and induce cell apoptosis. Brucine-mediated cell cycle arrest in G1 phase was associated with a marked increase of protein levels of CCND1 and decrease in CCNB1, cyclin E and CDC2. In addition, Brucine dose-dependently caused LoVo cells apoptosis evidenced by Annexin V/PI staining Brucine-induced apoptosis was mediated via up-regulation of Bax and down-regulation of Bcl-2. Furthermore, proteins Erk1/2, p38 and Akt phosphorylation were down regulated by Brucine in a dose-dependent manner. In summary, this paper indicates Brucine is effective against LoVo cells proliferation, and promotes LoVo cells death via apoptosis. These results reveal functional interplay among a series of pathway that are deregulated in cancer and suggest that their simultaneous targeting by Brucine could result in efficacious inhibition on cancer cells.     

The effects of dipyridamole and indomethacin on methotrexate cytotoxicity in LoVo human colon cancer cells

Dipyridamole and indomethacin were studied for their effects in the in-vitro response of LoVo colon cancer cells to methotrexate (MTX) using a dye elution method. Dipyridamole 0.5-5 micrograms mL-1 or indomethacin 1 microgram mL-1 alone had little or no effect on cell growth. The tumour cells were refractory to even high concentrations of MTX (2.5-10 micrograms mL-1) alone or with indomethacin 1 microgram mL-1. In contrast, dipyridamole 0.5-5 micrograms mL-1 sensitized the cells to MTX 5 micrograms mL-1 (their growth was reduced by 25 to 69%), possibly by inhibiting thymidine salvage.     

Potentiation of ara-C induced cytotoxicity by hydroxyurea in LoVo colon carcinoma cells

The present study was undertaken to determine whether cytotoxicity by 1-beta-D-arabinofuranosylcytosine (ara-C) in LoVo colon carcinoma cells, which are resistant to high concentrations of ara-C, would be enhanced by concurrent exposure to hydroxyurea (HU). Since mechanisms underlying the effects of HU on ara-C induced cytotoxicity are unclear, we also evaluated the effect of HU on the incorporation of ara-C into DNA, as well as potential consequences of misincorporation. Our results demonstrate that HU synergistically enhances cytotoxicity by ara-C in these cells. This effect was not present when HU was combined with aphidicolin, an agent that resembles ara-C in competing with dCTP for binding to polymerase alpha but that is not incorporated into DNA. Further, cells exposed to HU and ara-C incorporated up to 5-fold as much ara-C into DNA as cells solely treated with ara-C. While the extent of inhibition of DNA synthesis was comparable with cells exposed to HU and aphidicolin as those treated with HU and ara-C, recovery of DNA synthesis was delayed more significantly by the latter combination. These findings suggest that HU synergistically potentiates ara-C induced cytotoxicity by enhancing incorporation of ara-C in LoVo cell DNA.