C－myc基因表达水平与骨髓增生异常综合征临床特征的相关性分析

采用Ｓｐｅａｒｍａｎ秩次相关法分析了１５例骨髓增生异常综合征（ＭＤＳ）的骨髓细胞中Ｃ－ｍｙｃ基因表达水平与诸临床特征间的相互关系。结果表明，Ｃ－ｍｙｃ－ｍＲＮＡ水平与ＭＤＳ患者的无白血病转化生存时间呈负相关（Ｐ＜０．０１），但与外周血白细胞、血小板数及血红蛋白含量无显著相关。同时对Ｃ－ｍｙｃ表达与骨髓幼稚前体细胞异常定位（ＡＬＩＰ）的关系进行了初步探讨。     

Hypertension induces compensatory arterial remodeling following arteriotomy

BACKGROUND: Hypertension has been traditionally considered a risk factor for restenosis following carotid arteriotomy. Genetic and morphological response to carotid arteriotomy in normotensive Wystar-Kyoto (WKY), spontaneously hypertensive (SHR), and Milan hypertensive (MHS) rats were analyzed. MATERIAL AND METHODS: C-myc, angiotensin II receptor-1 (AT1), angiotensin II receptor-2 (AT2), endothelin-1 receptor A (ET(A)), endothelin-1 receptor B (ET(B)), Bcl-2 family-members (Bcl-2/Bax, Bcl-X(L/S)) were analyzed in surgically injured as well as uninjured carotids of WKY and hypertensive strains (HS). Thirty-day histology and morphometry were accomplished on injured and uninjured carotids. RESULTS: C-myc mRNA is activated earlier and/or to a greater extent in hypertensive strains than in WKY. AT1 mRNA increases in WKY after injury, while it decreases in SHR and MHS. AT2 shows the opposite, decreasing in WKY and increasing in hypertensive strains. ET(A) mRNA decreases in all strains although with different timing and levels, associated with a replacement by ET(B) mRNA. Bcl-2/Bax ratio gradually decreases in WKY, while it shows only a transient decrease in SHR and MHS 4 h after the injury. Negative remodeling is observed in all injured carotids, although neointima was detected in WKY only. Thirty days following arteriotomy, morphometry demonstrated a significant decrease of luminal area, with consistent gain in the medial area in WKY, whereas hypertensive strains showed significant increase of the luminal area, consistent with a contemporary decrease of the medial area. CONCLUSIONS: Vaso-relaxant AT2 and ET(B) induced limited vasoconstriction in HS. Less apoptosis in hypertensive rats reduced cell proliferation, contrasting c-myc. These responses favorably modulated media/lumen area ratio following arteriotomy in HS.     

RNA干扰Cdx2基因沉默对人胃癌裸鼠耐药模型Survivin和C-myc表达的影响

目的观察携带人尾型同源盒转录因子2（Cdx2）基因沉默的重组慢病毒颗粒（Cdx2-RNAi-LV）对人胃癌耐顺铂细胞SGC-7901／DDP裸鼠皮下移植瘤中Survivin和C—myc表达的影响。方法建立人胃癌耐顺铂细胞SGC-7901／DDP裸鼠皮下移植瘤模型,36只裸鼠随机分成3组（n=12）：PBS组、LV-RNAi组、Cdx2．RNAi-LV组;各组瘤体内分别注射磷酸盐缓冲液、慢病毒颗粒（0．5×10^8TU／m1）、含Cdx2基因重组慢病毒颗粒（0．5×10^8TU／m1）相应药物100μl,1次／3d,共6次;同时所有裸鼠腹腔注射药物顺铂（25mg／kg）,隔天1次,共10次;注射Cdx2-RNAi-LV病毒颗粒第20天后脱颈椎法处死裸鼠,完整切取肿瘤组织,并应用PT-PCR和Westernblot技术检测移植瘤中Survivin和C．myc基因的表达。结果Cdx2．RNAi．LV组、LV．RNAi组和PBS组的细胞均有Survivin、C—myc的mRNA和蛋白的表达,但各组细胞对应的Survivin、C—myc的mRNA和蛋白的表达水平有差别;Cdx2-RNAi—LV组Survivin、C．myc的mRNA和蛋白的表达量较PBS组和LV．RNAi组明显下调（P〈0．05）,而PBS组和LV—RNAi组比较差异元统计学意义（P〉0．05）。结论Cdx2基因沉默重组慢病毒颗粒瘤内注射下调人胃癌耐顺铂细胞裸鼠移植瘤Survivin和C-myc表达,可能是Cdx2基因沉默逆转肿瘤的耐药性机制之一。     

肝癌中Bcl-2、Bax和C-myc基因的表达及其临床意义

目的 探讨Bcl-2、Bax和C-myc基因表达在肝细胞癌(HCC)中的临床意义.方法 采用免疫组化技术检测不同HCC组织、癌旁组织及正常肝组织中的Bcl-2、Bax和C-myc蛋白表达.结果 Bcl-2、Bax和C-myc在HCC组织、癌旁组织和正常肝组织中均有部分阳性表达;Bcl-2和C-myc蛋白在HCC组织中呈高表达,其个体阳性率明显高于正常肝组织(P＜0.05);Bax蛋白在HCC组织中呈低表达,其个体阳性率明显低于正常肝组织(P＜0.05);Bcl-2基因的表达与HCC的发病年龄、性别、肿瘤大小、UICC分期和转移均无关;Bax基因的表达与HCC的发病年龄、性别、肿瘤大小和转移无关(P＞0.05),而与HCC的UICC分期有关(P＜0.05);C-myc基因的表达与HCC的发病年龄、性别、肿瘤大小和UICC分期无关(P＞0.05),而与HCC的转移有关(P＜0.05).结论 Bcl-2、Bax和C-myc基因相互协调作用,促进HCC的发生和发展.     

Effect of Acanthopanax giraldii Harms Var.Hispidus Hoo polysaccharides on the human gastric cancer cell line SGC-7901 and its possible mechanism

Objective To study the inhibitory effect of Acanthopanax giraldii Harms Var.Hispidus Hoo polysaccharides (AGP) onSGC-7901 gastric cancer cells and its possible mechanism. Methods Cell doubling time analysis, colony forming assay and MTT assay were adopted to study the inhibitory effect and its characteristics. We also analyzed the amount of protein expressed by oncogenes, antioncogenes and cell factors using flow cytometric analysis.Results AGP inhibited the proliferation of SGC-7901 cells and cell colony forming ability. AGP did not inhibit the viability and function of lymphocytes of peripheral blood in healthy subjects and human embryonic tenocytes, except for the highest dosage of AGP ( P <0. 05), which slightly inhibited the viability and function of the two types of normal cells. AGP inhibited the viability and function of SGC-7901 cells, except for the lowest dosages of AGPⅠ and AGPⅢ. There was a dose-effect relationship between the dosage of the AGP andSGC-7901 cells.The effect of the AGP at the molecular level was associated with the low protein expression of the c-myc and bcl-2 genes and the high protein expression of the p53, bax, fas and fas-L genes, as well as the cell factor TGFβ(1).The inhibitory effect of AGP was weaker than that of CDDP, but was stronger than that ofVitamine C. Conclusions Acanthopanax giraldii Harms Var.Hispidus Hoopolysaccharides selectively inhibited the proliferation, the colony forming ability, and the viability and function of human gastric cancer cells through the low protein expression of c-myc, bcl-2 and the high protein expression of p53, fas, fas-L and the cell factor TGFβ(1). The different inhibitory characteristics on the normal cells and cancer cells are possibly caused by gene and the cell factor expressions.     

补髓生血冲剂对慢性再生障碍性贫血患者骨髓造血干细胞bax、C-myc、Bcl-2基因表达水平影响的实验研究

目的 :探讨补髓生血冲剂对慢性再生障碍性贫血 (CAA)患者造血干细胞bax、C -myc和Bcl- 2基因表达水平影响和疗效机理。方法 :应用免疫组化染色法和酶联免疫测定法检测补髓生血冲剂治疗前后CAA患者造血干细胞bax、C -myc和Bcl- 2基因表达水平。结果 :治疗后CAA患者的bax基因阳性表达率下降 ,与对照组相比有显著性差异 (P <0 .0 1,P <0 .0 5 )。而C -myc及Bcl- 2基因阳性表达率与对照组相比无显著性差异 (P >0 .0 5 )。结论 :补髓生血冲剂的作用机制之一可能是通过降低bax和C -myc基因的阳性表达率以抑制细胞凋亡 ,而并非在于促进调亡抑制基因Bcl- 2表达所致。     

p16与C—myc在喉鳞状细胞癌中的表达意义

目的：研究p16和C－myc在喉鳞状细胞癌中的表达意义。方法：应从p16和C－myc单克隆抗体，通过免疫组织化学法检测6例正常喉粘膜和47例喉鳞癌中p16和C－myc的表达。结果：6例正常喉粘膜组织中未发现p16和C－myc蛋白阳性表达，47例喉鳞癌中p16和C－myc阳性表达率分别为48．9％（23／47）和57.4％（27／47），与性别、年龄和肿瘤发生的部位无相关性（P＞0．05），与临床分期和病理分级相关（P＜0．05）；C－myc还与颈淋巴结转移相关（P＜0．05）。结论：p16和C-myc蛋白阳性表达在喉鳞癌的发生和发展中起重要作用，可作为评价喉鳞癌预后的新指标。     

非小细胞肺癌中p65和C-myc的表达及意义

 目的　探讨 p6 5和C myc蛋白在非小细胞肺癌 (NSCLC)组织中的表达及临床意义。 方法　在肺支气管粘膜上皮不典型增生 11例、NSCLC 4 0例中 ,用免疫组化二步法检测 p6 5和C myc蛋白的表达 ,并将结果进行相关分析。结果　p6 5和C myc蛋白在肺癌组织中的表达与在肺支气管粘膜上皮不典型增生的表达比较差异均有显著性 (P <0 .0 1) ;p6 5和C myc蛋白在肺癌的表达与肺癌组织类型、分化及转移无关 (P >0 .0 5 ) ;肺癌中 p6 5与C myc的表达具有相关性 (Pearson列联系数 =0 .4 14 3,P <0 .0 1)。结论　p6 5和C myc蛋白在NSCLC组织中表达上调 ,提示可能通过抑制肺癌细胞凋亡 ,对肺癌的发生发展起重要促进作用。     

Differential effects of cigarette smoke extracts on cell proliferation in gastric and colon cells

Substantial evidence show a higher incidence of gastric cancer in smokers than nonsmokers and that cigarette smoking is highly associated with colon cancer. The present study was designed to examine the effect of cigarette smoke extracts on gastric and colon cancer cell proliferation, which is important for tumor growth. Two different cell lines were used. One was gastric cancer cell line AGS, and the other was colon cancer cell line HT-29. It was found that cigarette smoke extracts stimulated cell proliferation and c-myc expression in AGS cells. Furthermore, this proliferative action was partially blocked by the c-myc antisense. However, the extracts significantly inhibited HT-29 cell proliferation and suppressed c-myc expression. In conclusion, cigarette smoke extracts stimulated AGS cell proliferation, while inhibiting HT-29 proliferation, which were partially mediated by a c-myc-related pathway. The former action may play a contributory role in the carcinogenic action of cigarette smoking in the stomach.