胃腺癌差异表达基因的cDNA微阵列研究

目的：应用cDNA基因芯片研究筛选人胃腺癌相关差异表达基因，探讨胃癌发生、发展的分子机制。方法：运用含18000个基因克隆的cDNA膜基因芯片，对6对胃腺癌及正常胃组织标本分别进行杂交检测并对比分析。结果：6对人胃腺癌与相对应的胃正常组织相比较，筛选出在3～6对标本中有2倍以上改变的基因克隆共有103条(1条在所有标本中均差异明显)，其中胃癌组织表达上调基因56条，胃癌组织表达下调基因47条。结论:人胃腺癌癌变是一个多基因参与的过程，基因芯片技术是一种快速有效的筛选人胃腺癌差异表达基因的方法。     

胃腺癌差异表达基因的cDNA微阵列研究

目的:应用cDNA基因芯片研究筛选人胃腺癌相关差异表达基因, 探讨胃癌发生、发展的分子机制。方法: 运用含18 000个基因克隆的cDNA膜基因芯片,对6 对胃腺癌及正常胃组织标本分别进行杂交检测并对比分析。结果: 6 对人胃腺癌与相对应的胃正常组织相比较,筛选出在3~6 对标本中有2 倍以上改变的基因克隆共有103条(1 条在所有标本中均差异明显),其中胃癌组织表达上调基因56条, 胃癌组织表达下调基因47 条。结论: 人胃腺癌癌变是一个多基因参与的过程, 基因芯片技术是一种快速有效的筛选人胃腺癌差异表达基因的方法。     

大鼠肝癌高表达基因cDNA序列的克隆

目的克隆出大鼠肝癌高表达EST片段相关基因的cDNA完整表达序列,为进一步揭示其生物学功能奠定基础。方法通过基因芯片检测出DEN诱发的大鼠肝癌高表达的EST片段;其中部分高表达的EST片段,采用电子克隆与PCR相结合的方法,克隆出其cDNA完整表达序列。结果与正常大鼠肝组织比较,肝癌组织中明显高表达的EST片段有34个。采用EST电子克隆技术与PCR技术相结合的方法,成功克隆出4个EST片段的cDNA序列,经进一步BLAST对比分析,证明G15、G20、G36、G40等4个基因为新基因,并进行GenBank登录,登录号分别为DQ480746、DQ480747、DQ480744、DQ912022。结论利用大鼠基因芯片高通量地筛选出DEN诱发的肝癌组织高表达的有关基因,并在充分利用生物信息学资源的基础上,成功克隆出4个新基因的cDNA序列,为今后进一步深入观察这些基因的功能及其在肝癌发生、发展过程中的作用机制打下良好的研究基础。     

大鼠腹部手术应激后血清miRNA表达谱的差异分析

目的:应用miRNA芯片技术建立大鼠腹部手术应激后血清miRNA差异表达谱,从中发现与早期手术创伤后应激相关的miRNAs。方法:建立大鼠部分肝切除手术模型。检测手术前后大鼠血清中ALT、AST和CRP浓度水平及肝脏病理改变,评估腹部创伤后大鼠应激情况。采用miRNA表达谱芯片筛选手术前后大鼠血清中差异表达的miRNAs,并采用实时荧光定量RT-PCR(real-time RT-PCR)进行验证。采用生物信息学软件(MiRand和TargetScan)预测候选miRNA的靶基因。结果:血清miRNA表达谱出现明显改变,24个miRNAs在2/3部分肝切除术（PH）后24h大鼠血清中表达明显升高,特别是miR-9,其在2/3PH术后24h大鼠血清中的表达水平为术前的50多倍,real-time RT-PCR检测miR-9的结果与芯片结果相符。通过生物信息学预测,CDH1、E-cadherin、MTHFD2、PDYN、MCPIP1、BCL2L11、CMA1、Map3k1等可能是miR-9的靶基因。结论:腹部手术创伤后,大鼠血清表达谱发生明显变化,提示miRNA可能参与调控创伤后应激反应。     

大鼠闭合性脑损伤后不同脑区蛋白质表达的差异比较

目的研究大鼠脑损伤后大脑皮质、海马和脑干中蛋白质表达的特点及差异。方法56只雄性SD大鼠,随机分为正常对照组、手术对照组及损伤组,后者于损伤后4 h、8 h、12 h、24 h和48 h不同时间取材观察。复制Marmarou’s落体打击脑损伤模型,应用弱阳离子交换芯片（WCX-2）和固定金属亲和吸附芯片（IMAC-Cu）结合表面增强激光解析电离飞行时间质谱技术分析大鼠闭合性脑损伤后皮质、海马和脑干中蛋白质表达谱的变化。结果（1）在WCX-2芯片上,大脑皮质中共捕获404个蛋白质峰;海马中共捕获364个蛋白质峰;脑干中共捕获495个蛋白质峰。在IMAC-Cu芯片上,皮质中共捕获203个蛋白质峰;海马中共捕获345个蛋白质峰;脑干中共捕获107个蛋白质峰。（2）与手术对照组相比,损伤组大脑皮质在两种芯片上共有38个蛋白质峰的相对强度差异有统计学意义（P〈0.05）;海马在两种芯片上共有49个蛋白质峰的相对强度差异有统计学意义（P〈0.05）;脑干在两种芯片上共有27个蛋白质峰的相对强度有显著性差异（P〈0.05）。结论（1）脑损伤可引起不同脑区中蛋白质表达谱发生变化。（2）不同脑区蛋白质表达谱存在差异。     

乳腺癌组织中DNA甲基化转移酶与多药耐药基因ABCG2表达的关系

背景与目的:研究乳腺癌组织中DNA甲基化转移酶(DNA methyltransferase,DNMT)与多药耐药基因ABCG2表达的关系,以进一步探讨ABCG2表达的表观遗传学机制.材料与方法:用实时定量RT-PCR法检测22例乳腺癌及其匹配的癌旁组织中DNMT1、DNMT3A、DNMT3B和ABCG2的表达.并采用Spearman等级相关分析DNMTs与ABCG2基因表达的相关性.结果:乳腺癌组织中ABCG2、DNMT1、DNMT3A、DNMT3B mRNA表达量显著高于癌旁组织(P<0.01),并且DNMT3B表达量显著高于DNMT1和DNMT3A(P<0.01),与ABCG2基因表达呈负相关性(r=-0.664,P<0.01). 结论:乳腺癌组织中DNMT3B可能参与了ABCG2基因的表达调控,这为寻找药物靶点并逆转其介导的药物耐受提供了新的科学依据.     

基因表达谱芯片胃癌差异表达基因的筛选

目的:利用基因表达谱芯片研究胃癌组织中差异表达的基因,从多基因角度研究胃癌发生的分子机制.方法:抽提6例胃癌组织和相应的癌旁组织的总RNA,反转录成cDNA同时进行标记.将标记的cDNA与基因表达谱芯片杂交,经过芯片的扫描和数据处理,分析出胃癌组织和癌旁组织之间差异表达的基因.结果:通过对胃癌组织和癌旁组织的基因表达谱的比较分析,发现在胃癌组织中表达差异＞2倍的基因共有696个,其中表达上调的基因318个,表达下调的基因378个.差异表达的基因主要参与信号转导、免疫反应和细胞运动等生物学过程.结论:胃癌组织与癌旁组织的表达谱存在较大差异,利用基因表达谱芯片可筛选出胃癌差异表达的基因,从而有利于在临床上对肿瘤的诊断和治疗.     

B细胞非霍奇金淋巴瘤患者TCR ζ基因的表达特点

 目的 分析B细胞非霍奇金淋巴瘤（B-NHL）患者外周血中T细胞信号转导分子TCRζ基因的表达特点。 方法 采用SYBR GreenⅠ实时定量RT-PCR和相对定量分析法检测17例B-NHL患者外周血单个核细胞 （PBMCs）中TCR ζ 基因的表达情况,以β2微球蛋白基因（β2M）作为内参, 采用相对定量 公式：2－△ Ct ×100%,计算TCR ζ基因的相对mRNA 表达量,17例健康成人作为对照。 结果 全部B-NHL样本均全部表达TCR ζ 基因,但其表达水平显著低于对照组（ P =0.000）,健康 人PBMCs的TCR ζ 基因mRNA的表达水平为B-NHL患者的3.26倍。B-NHL患者TCR ζ基因表达水平 与患者的年龄无相关性。 结论 B-NHL患者中TCR ζ基因的mRNA表达水平明显下调,可能是其细胞免疫功能缺陷的原因之一。     

不同转移潜能骨肉瘤细胞差异表达基因的筛查

目的: 研究不同转移潜能骨肉瘤细胞差异表达的基因,筛选骨肉瘤转移相关的基因。方法: 分别提取低转移骨肉瘤细胞株M6和高转移骨肉瘤细胞株M8细胞总RNA,采用cDNA基因芯片筛查M6和M8细胞差异表达的基因,杂交信号用Generation Ⅲ array扫描,结果用Imagequant 5.0软件分析。选择基因芯片筛选到的典型差异表达基因用实时定量PCR进行验证。结果: M6和M8骨肉瘤细胞株差异表达的基因共有330个,其中与低转移组（M6）相比,在高转移组（M8）中显著性上调表达的基因有178个,下调表达的基因有152个。其中发生非常显著性上调表达的基因43个,发生非常显著性下调表达的基因49个。差异基因主要包括与细胞增殖相关的基因,提示与M8细胞增殖受抑相关;其次是与基因表达调控及信号转导相关的基因,提示这些基因和肿瘤转移有关联性。结论: 基因芯片方法对于筛选骨肉瘤转移相关基因有独特的优势,MG63细胞M8亚株中筛查到显著性上调的基因43个,显著性下调的基因49个,与骨肉瘤的转移有关。     

心理应激对大鼠睾丸细胞雄性激素受体表达的影响

目的 :探讨心理应激对大鼠睾丸细胞雄性激素受体 (androgenreceptor ,AR)表达的影响。方法 :采用心理应激大鼠模型 ,以免疫组化与微机图象分析检测相结合技术 ,观测大鼠心理应激后睾丸间质细胞、血管壁外膜和其它间质组织AR的表达程度 ,以及AR阳性产物的相对光密度、AR阳性睾丸间质细胞的体积密度 (VV)和AR阳性睾丸间质细胞数密度 (NV)的变化。结果 :闪光间期长短不均加电剌激组 (A组 )、闪光间期恒定加电剌激组 (B组 )和单纯闪光间期长短不均组 (C组 ) 3组比较 ,在睾丸间质细胞、血管壁外膜和其它间质组织的AR阳性表达强度、AR阳性产物相对光密度及AR阳性的睾丸间质细胞VV 和NV 等方面 ,均显示出明显的差异 ,即A组 相似文献   

盐酸阿比朵尔对大鼠的致畸胎作用

背景与目的盐酸阿比朵尔(Arbidol hydrochloride,Ar)为防治流行性感冒新药,为保证临床用药的安全,观察其对大鼠的致畸作用和胚胎毒性。材料与方法将80只妊娠SD大鼠分为5组,即对照组、Ar100、330、1000mg/(kg.d)剂量组和水杨酸钠阳性药组,每组16只大鼠。各组大鼠均于妊娠6~15d连续灌胃给药,妊娠20d解剖。结果Ar高剂量1000mg/(kg.d)使孕鼠体重增长减慢,孕期体重净增值减少,活胎率降低,胎鼠体重、身长和尾长减小,胎鼠骨化迟缓率增加,与对照组比较差异具有统计学意义(P<0.05,P<0.01);但未见胎鼠外观、内脏和骨骼畸形。Ar低和中剂量[100mg/(kg.d)和330mg/(kg.d)]对孕鼠和胎鼠无明显影响。结论330mg/(kg.d)为孕鼠的安全剂量,1000mg/(kg.d)在引起孕鼠毒性反应时有一定的胚胎毒作用,但无致畸胎作用。     

脱氢表雄酮对大鼠的发育毒性

背景与目的:探讨脱氢表雄酮(dehydroe piandrosterone,DHEA)的发育毒性。材料与方法:将SD孕鼠随机分为5组,每组16只,分别为阳性对照组(阿司匹林300mg/kg),阴性对照组(蒸馏水)和DHEA10.4、20.8、41.7mg/kg3个剂量组,在受孕第7~16d连续10d给大鼠灌胃DHEA,第20d解剖取出胎鼠,观察DHEA对母体及胎鼠的影响。结果:DHEA剂量在10.4mg/kg时导致孕鼠流产;20.8、41.7mg/kg时孕鼠、胎鼠体重增加减缓,胸骨发育迟缓;41.7mg/kg时,胎鼠内脏畸形增加。3个剂量组胎鼠活胎率均降低。结论:DHEA对孕鼠及胎鼠均有毒性表现。     

Forestomach Neoplasm Induction in F344/DuCrj Rats and B6C3F1 Mice Exposed to Sesamol

Sesamol was administered at a dietary level of 2% to groups of 30 male and female F344/DuCrj rats and B6C3F, mice for 104and 96 weeks, respectively. Squamous cell carcinomas in the forestomach were Induced in nine of 29 (31%) effective male rats, three of 30 (10%) female rats, eleven of 29 (38%) male mice and five of 30 (17%) female mice treated with sesamol. Papillomas developed in ten of 29 (34%) male rats and fourteen of 30 (47%) female rats, but not in any of the mice. Hyperplasias developed in almost all rats and mice of both sexes. Significant differences from control values were found for all three lesions in rats and for carcinoma and hyperplasia categories in mice. The incidences of other tumors in the 2% sesamol group were comparable with control values. In conclusion, sesamol induces squamous cell carcinomas in the forestomach of rats and mice, males being more susceptible than females.     

Combination Effects of Forty Carcinogens Administered at Low Doses to Male Rats

An investigation was conducted to determine whether a mixture of low doses of forty carcinogens that target different organs, including the liver, intestine, thyroid, urinary bladder, and skin, is effective for tumor induction in F344/DuCrj rats. The dose of each carcinogen in the diet was 1/50 of the TD₅₀ value, treatment being continued for 102 weeks. Significant numbers of neoplastic nodules of the liver and follicular cell tumors of the thyroid developed in the animals exposed to the carcinogen mixture, although the question of whether the observed carcinogenic effects were synergistic or additive could not be answered. The results serve to evaluate carcinogenic risk in the search for causes of human cancer.     

大剂量维生素E和C抗氧化活性及对DNA损伤影响的研究

背景与目的:观察大剂量维生素E(VitaminE,VE)和C(VitaminC,VC)的抗氧化活性及对大鼠DNA氧化损伤、烷化损伤的影响。材料与方法:将72只Wistar大鼠(雌雄各半)随机分为6组,每组12只,即对照组(基础饲料,VE、VC摄入量分别为5、0mg/kg·d),VC组(VE5mg/kg·d、VC1000mg/kg·d),VE1组(VE33mg/kg·d、VC0mg/kg·d),VE2组(VE500mg/kg·d、VC0mg/kg·d),VE1 VC组(VE33mg/kg·d、VC1000mg/kg·d)和VE2 VC组(VE500mg/kg·d、VC1000mg/kg·d),实验期为8周。实验结束前收集动物24h尿液,实验结束后处死动物,留取血液,分离血浆并收集淋巴细胞,测定超氧化物歧化酶(Superoxidedismutase,SOD)、谷胱甘肽过氧化物酶(Glutathioneperoxidase,GSH-Px)活性、丙二醛(Malondialdehyde,MDA)含量,分析DNA损伤。结果:VE1组的抗氧化活性显著提高:血浆SOD、GSH-Px活力明显高于对照组(P<0.05)、MDA含量低于对照组;而VE1 VC组SOD、GSH-Px则较VE1组显著下降(P<0.05)。VE1组10μmol/LH2O2诱导的淋巴细胞DNA氧化损伤为150.42AU,显著低于其它组(P<0.05);该组DNA烷化损伤产物尿O6-甲基鸟嘌呤(O6-methylguanine,O-6meG)含量为0.89mg/g肌酐,比对照组、VE2组分别下降了50.28%、50.00%(P<0.05)。结论:较大剂量VE能提高大鼠抗氧化活性,降低DNA氧化损伤及烷化损伤,但联合补充大剂量VC时可能对其影响产生拮抗作用;过大剂量VE和VC补充时均未观察到有利作用,并且可能降低机体的遗传稳定性。     

cDNA Array Analysis of SPARC-modulated Changes in Glioma Gene Expression

We have demonstrated that secreted protein acidic and rich in cysteine (SPARC) is highly expressed in human gliomas and it promotes glioma invasion and delays tumor growth in vitro and in vivo. cDNA array analyses were performed to determine whether SPARC, which interacts at the cell surface, has an impact on intracellular signaling and downstream gene expression changes, which might account for some of its effects on invasion and growth. Using a doxycycline (dox)-controlled gene expression system, two cDNA array analyses were performed using a parental U87T2 clone (–SPARC) transfected with the dox-controlled transactivator and a U87T2 parental-derived SPARC-transfected clone, A2b2 (+SPARC). Array analysis performed between the parental and the SPARC-transfected clone (–dox) identified 13 upregulated genes and 14 downregulated genes. With the exception of PAI-1 and MMP2, the identified genes are novel with respect to SPARC's mechanism of action. Array analysis performed using the SPARC-transfected clone (±dox) identified 2 types of gene regulation; one reversible upon SPARC suppression, the other irreversible. Two of the SPARC-induced genes, BIGH3 (irreversible by dox) and PAI-1 (reversible by dox) were further studied in additional SPARC-transfected clones, human astrocytoma tissues, and human glioma cell lines by RT-PCR and Northern blot analyses. The results indicate that: (1) the array results were validated, (2) the dox regulation was validated, and (3) the differential expression identified by the array analyses was present between normal brain and in human astrocytoma tissues and cell lines. Therefore, we conclude that these cDNA array analyses provide candidate genes involved in SPARC-mediated effects on glioma cell cycle progression, signaling, and migration, and that SPARC may induce reversible and irreversible gene expression changes. Further investigation of these candidates may shed insights into SPARC's role in glioma cell proliferation and invasion, and potential use as a therapeutic target.     

Low Tumorigenic Response to 3,2'-Dimethyl-4-aminobiphenyl Administration in the Prostate of Rats Castrated at Birth

Six-week-old rats which had been orchiectomized at birth were given 3,2'-dimethyl-4-aminobiphenyl (DMAB) at various doses combined with a stimulus to prostate epithelial cell proliferation in the form of oral administration of methyltestosterone (MT) for 4 weeks. Thereafter MT treatment was continued or the animals received subcutaneous implants of testosterone propionate (TP) and were maintained until sacrifice at week 60. Although prostatitis and prostatic enlargement were frequently observed, especially in the TP group, numbers of atypical hyperplastic lesions were low and only one prostatic carcinoma in situ developed. Thus, despite the presence of proliferation, castration brought about a significant reduction in susceptibility to DMAB.     

Prediction of Sensitivity to STI571 among Chronic Myeloid Leukemia Patients by Genome-wide cDNA Microarray Analysis

One of the most critical issues to be solved in regard to cancer chemotherapy is the establishment of ways to predict the efficacy of anti-cancer drugs for individual patients. To develop a prediction system based on expression of specific genes, we analyzed expression profiles of mononuclear cells from 18 chronic myeloid leukemia (CML) patients who were treated with the tyrosine kinase inhibitor STI571. cDNA microarrays representing 23 040 genes identified 79 genes that were expressed differentially between responders and non-responders to STI571. On the basis of the expression patterns of 15 or 30 of these genes among the patients, we developed a "Prediction Score" system that could clearly separate the responder group from the non-responder group. Verification of this system using four additional ("test") cases succeeded in predicting the response of each of those four patients to the drug. These results provide the first evidence that gene-expression profiles can predict sensitivity of CML cells to STI571, and may eventually lead to the achievement of "personalized therapy" for this disease.     

Lack of Chronic Oral Toxicity of Chemopreventive Bovine Lactoferrin in F344/DuCrj Rats

Studies were undertaken to determine whether bovine lactoferrin (bLF) and related compounds, shown to prevent carcinogenesis in the colon and other organs in rats, have any toxic effects in long-term feeding studies. In experiment I, male F344/DuCrj rats received a basal diet containing 0.2% bLF for 40 weeks. No adverse findings were noted, furthermore, serum triglyceride level was significantly decreased to 72% of the control level, suggesting preventive effects against the metabolic syndrome. In experiment II, male and female F344/DuCrj rats were fed a basal diet containing 0.02, 0.2, 2.0 and 5.0% bLF, 2.0% bLF hydrolysate (bLF-H) or 0.1% lactoferricin (LFcin), a peptide derived from bLF, for 60 weeks in males and 65 weeks in females. No toxicological effects, including carcinogenicity, were evident in either sex. The results of the studies provide subjective support for safety of clinical studies of bLF for supplement use.     

维生素C对顺铂治疗大鼠卵巢癌疗效的影响

目的：探讨维生素 C 是否能影响顺铂对于大鼠卵巢癌的化疗效用,并对其作用机制进行初探。方法：建立卵巢癌大鼠模型,将大鼠随机分组后腹腔给药,每周观察一般状况变化。8周后,脱颈处死各组大鼠,取血清检测 CA125、HE4并计算 ROMA 值,测量腹水容积,解剖并观察统计肿瘤生长情况,对局部肿块及主要组织进行测量,常规病理学检查。结果：所有大鼠外观消瘦,体重随着腹水和肿瘤的出现呈现增长,顺铂+高剂量维生素 C 组的肿瘤质量及腹水容积明显小于其余三组,实验组的 CA125、HE4及 ROMA 明显低于对照组,顺铂+高剂量维生素 C 组的 CA125、HE4及 ROMA 则明显低于顺铂+低剂量维生素 C 组及顺铂组,实验组患恶性肿瘤的大鼠比例降低,而是否添加维生素 C 对数据则无明显影响。结论：注射较高浓度维生素 C 能增强顺铂杀伤卵巢癌的能力,并呈现一定的剂量依赖性。