胃粘膜HP感染致癌机制的病理学探讨

目的 探讨胃上皮细胞增殖癌变与幽门螺杆菌(Hp)感染的关系及Hp感染致癌的可能机制.方法 应用特殊染色法将各种病变分为Hp感染阳性组和阴性组,应用免疫组化对各组病变的Ki-67,p53,CerbB-2,C-MYC表达进行检测.结果 总体上看,Hp阳性组Ki-67,p53,CerbB-2,C-MYC表达的阳性率明显高于Hp阴性组;且Hp阳性组总体Ki-67,p53,CerbB-2,C-MYC表达的阳性率明显高于Hp阴性组总体(P＜0.05);Ki-67,p53,CerbB-2,C-MYC表达的阳性率随病变程度的加重而逐渐增加.结论 Hp感染可促进胃上皮细胞过度增殖、癌变.这种上皮细胞基因蛋白的改变可能是Hp感染致胃癌的机制之一.     

互补于hTERT关键区段的反义RNA抑制肝癌细胞

目的研究针对人类端粒酶催化亚单位(hTERT)调控区C-MYC结合位点的反义RNA抑制肝癌细胞生长。方法细菌内同源重组构建反义RNA腺病毒(rAd-asmycb),转染HepG2.2.15肝癌细胞,流式细胞术检测细胞凋亡,透射电镜下观察凋亡细胞形态,聚合酶链反应-酶联免疫分析(PCR-ELISA)、逆转录-PCR(RT-PCR)分别检测细胞端粒酶活性及mRNA水平上hTERT表达。结果反义RNA抑制肝癌细胞生长,细胞凋亡率为40.7%,显示特征性凋亡细胞形态,能够显著降低细胞端粒酶活性,在mRNA水平上抑制hTERT表达。结论hTERT调控区C-MYC结合位点可能是肝癌基因治疗的有效靶位。     

脂质体介导的C-myc反义寡核苷酸在视网膜色素上皮细胞中分布和稳定性的观察

目的；在体外培养的人视网膜色素上皮（RPE）细胞中，观察脂质体（Lipofectamine)介导的C-myc反义寡核苷酸转染效果，为进一步研究增生性玻璃体视网膜病变（PVR）的防治提供实验依据。方法：将人工合成带有FAM荧光标记的反义寡核苷酸（AS－ODN）用脂质体包裹转染体外培养的RPE细胞，同时用无脂质体介导的裸AS－ODN作对比，在荧光显微镜下动态观察AS－ODN在RPE细胞内的分布和存留时间。结果：与无脂质体介导的裸AS－ODN相比，脂质体介导的AS－ODN在细胞内，尤其在胞核的分布明显加强；不仅转染速度快，而且在细胞的存留时间延长1倍以上。结论：脂质体能明显增强AS－ODN在RPE细胞内的转染效率，有望进一步用于防治PVR的研究。     

C-MYC siRNA对急性淋巴细胞白血病Jurkat细胞凋亡的诱导作用

本研究探讨C-MYC siRNA对急性淋巴细胞白血病细胞系Jurkat细胞的增殖、凋亡的影响.采取化学合成法合成针对C-MYC rnRNA的第1545-1565靶位点设计的siRNA,经转染剂(HiPerFect transfection reagent)转染入Jurkat细胞,观察细胞形态学变化;应用四唑氮化合物(MTS)法绘制细胞生长曲线;用细胞集落培养观察C-MYC siRNA对Jurkat细胞增殖的影响;应用流式细胞术和TdT酶介导的末端缺失原位标记(TUNEL)法分析细胞的凋亡.结果表明,不同浓度C-MYC siRNA作用于Jurkat细胞后,细胞的生长受到不同程度的抑制,抑制率随C-MYC siRNA浓度的增高而增高.C-MYC siRNA对集落形成也有明显的抑制作用.TUNEL法、流式细胞仪均检测出细胞凋亡,且随着作用时间的延长,其凋亡率也逐渐上升.结论:化学合成法合成的C-MYC siRNA能明显抑制Jurkat细胞的增殖与集落形成,并可诱导 Jurkat细胞发生凋亡.     

Leptin对子宫颈癌Hela细胞生物学行为的影响及机制

目的 观察瘦素(Leptin)对子宫颈癌Hela细胞生物学行为的影响,并探讨其机制.方法 用不同浓度Leptin重组蛋白处理子宫颈癌Hela细胞,MTT法检测细胞增殖状态的变化;流式细胞仪检测瘤细胞周期变化及凋亡;RT-PCR检测C-MYC基因的表达;Western blot检测C-MYC蛋白质的表达.结果 Leptin明显促进子宫颈癌Hela细胞的增殖并抑制细胞的凋亡;Leptin激活子宫颈癌Hela细胞中C-MYC基因及其蛋白质的表达.结论 Leptin通过激活C-MYC的表达促进子宫颈癌Hela细胞的增殖并抑制其凋亡,其作用机制通过激活癌基因C-MYC而发挥效应.     

INCREASED EXPRESSION OF PDGF AND C－MYC GENES IN LUNGS AND PULMONARY ARTERIES OF PULMONARY HYPERTENSIVE RATS INDUCED BY HYPOXI

ＩＮＣＲＥＡＳＥＤＥＸＰＲＥＳＳＩＯＮＯＦＰＤＧＦＡＮＤＣ－ＭＹＣＧＥＮＥＳＩＮＬＵＮＧＳＡＮＤＰＵＬＭＯＮＡＲＹＡＲＴＥＲＩＥＳＯＦＰＵＬＭＯＮＡＲＹＨＹＰＥＲＴＥＮＳＩＶＥＲＡＴＳＩＮＤＵＣＥＤＢＹＨＹＰＯＸＩＡ￥ＣａｉＹｉｎｇｎｉａｎ；（蔡英年...     

Modulation of pro- and anti-apoptotic genes in lymphocytes exposed to bone cements

The ability of bone cements to modify the apoptotic program in activated immune cells and the mechanisms by which they act were evaluated. Mononuclear cells were collected from healthy individuals, cultured for 4 and 24 h with phytohemoagglutinina-P and cement extracts and then tested to assess: (a) cell viability; (b) early apoptotic events, by Annexin V/propidium iodide staining; and (c) the expression of pro- (p53, c-myc, ICE) and anti-apoptotic (bcl-2) genes. After 4 h three cements were able to increase significantly the percentage of apoptotic cells, while after 24 h no differences were found. The proportion of dead cells was not significantly changed at either culture time. The simultaneous expression of both pro-apoptotic (ICE, c-myc, p53) and antiapoptotic genes (bcl-2) was investigated only with regard to the materials which induced significant changes in apoptosis: two cements induced the p53 expression, while the third down-regulated bcl-2. As apoptosis regulates the balance of immune response, the authors recommend that the interaction between materials and immune cells should be assessed, so that the use of pro-apoptotic materials may be avoided in patients with immune defects.     

不同宫颈病变组织中C-MYC基因与P16蛋白的表达

目的:检测不同宫颈病变组织中C-MYC基因和P16蛋白的表达.方法:选择慢性宫颈炎40例,宫颈上皮内瘤变(CIN)I级108例,CINⅡ级50例,CINⅢ级35例,浸润性宫颈鳞状细胞癌38例,腺癌14例,分别采用荧光原位杂交技术和免疫组化SP技术检测各级宫颈病变组织中C-MYC基因及P16蛋白的表达.结果:随宫颈病变级...     

Relationship of Amplification and Expression of the C-MYC Gene with Survival among Gastric Cancer Patients

Background: During the past decades, the incidence and mortality rate of stomach cancer has demonstrateda great decrease in the world, but it is still one of the most common and fatal cancers especially among menworldwide, including Iran. The MYC proto-oncogene, which is located at 8q24.1, regulates 15% of genes and isactivated in 20% of all human tumors. MYC amplification and overexpression of its protein product has beenreported in 15-30% of gastric neoplasias. The aim of this investigation was to find the relative efficacy of CISH(chromogenic in situ hybridization) or IHC (immunohistochemistry) in diagnosis and prognosis of gastric cancer,as well as the relationship of amplification and expression of C-MYC gene with patient survival. Materials andMethods: In this cross-sectional study, 102 samples of gastric cancer were collected from patients who hadundergone primary surgical resection at the Cancer Institute Hospital, Tehran University of Medical Sciences,from July 2009 to March 2014. All samples were randomly selected from those who were diagnosed with gastricadenocarcinomas. CISH and IHC methods were performed on all of them. Results: Patients were classifiedinto two groups. The first consisted of stage I and II cases, and the second of stage III and IV. Survival tests forboth groups was carried out with referrnce to CISH test reults. Group II (stage III & IV) with CISH+ featuredlower survival than those with CISH- (p=0.233), but group I (stage I & II) patients demonstrated no significantvariation with CISH+ or CISH- (p=0.630). Kaplan-Meier for both groups was carried out with IHC test findingsand showed similar results. This data revealed that both diffuse and intestinal types of gastric cancer occurredsignificantly more in men than women. Our data also showed that CISH+ patients (43%) were more frequentin comparison with IHC+ patients (14.7%). Conclusions: For planning treatment of gastric cancer patients, byfocusing on expanding tumors, which is the greatest concern of the surgeons and patients, CISH is a better andmore feasible test than IHC, in regard to sensitivity and specificity. Therefore, CISH can be used as a feasible testfor tumor growth and prognosis in stage III and IV lesions. This study also indicated that C-MYC amplificationin gastric cancer is correlated with survival in advanced stages.