X射线全身照射对小鼠胸腺细胞p53,p21,GADD45及MDM2蛋？…

目的;观察电离辐射全身照射对小鼠胸腺细胞;ｐ５３,ｐ２１,ＧＡＤＤ４５及ＭＤＭ２蛋白表达的影响。方法：采用间接免疫荧光标记,流式细胞术检测蛋白表达的变化。结果：２ＧｙＸ射线照射后１－８ｈｐ５３蛋白表达显著增高;照射后４－４８ｈｐ２１蛋白表达显著增高;ＭＤＭ２蛋白在照后４ｈ及８ｈ显著增高;而ＧＡＤＤ４５蛋白表达在照后１－４８ｈ内无明显变化。     

电离辐射对小鼠胸腺和脾细胞MDM2mRNA和蛋白表达的影响

目的：探讨Ｘ射线全身照射诱导小鼠胸腺和脾细胞Ｇ１期阻滞的分子机制。方法：采用流式细胞术和斑点印迹杂交检测Ｘ射线全身照射后昆明系小鼠胸腺和脾细胞中ＭＤＭ２ｍＲＮＡ和蛋白表达的变化。结果：２ＧｙＸ射线全身照射后４～８ｈ小鼠胸腺细胞ＭＤＭ２蛋白的表达明显升高（Ｐ〈０．０５）。时效和量效观察发现,无论是７５ｍＧｙ还是１ＧｙＸ射线全身照射,小鼠胸腺和脾细胞中ＭＤＭ２ｍＲＮＡ水平在照后１～４８ｈ均未见明显变化     

MDM2,P53蛋白在星形细胞瘤中的表达

探讨ＭＤＭ２、Ｐ５３蛋白在星形细胞瘤发病中的作用及其与肿瘤病理分级，患者预后间的关系。方法用免疫组化技术链霉亲和素－生物素－过氧化物酶复（ＳＡＢＣ）法对确诊并有随访的４５例星形细胞瘤标本进行ＭＤＭ２、ｐ５３蛋白定位观察。结果发现ＭＤＭ２ｐ５３蛋白表达阳性率分别为４８．９％（２２／４５）和４６．７％（２１／４５），其阳性率与肿瘤病理分级呈显著正相关。本组中ＭＤＭ２和Ｐ５３共同性表达１２例，占２６．７     

肺癌MDM2蛋白表达与p53基因突变的关系

目的：研究肺癌ＭＤＭ２蛋白表达与ｐ５３突变之间的关系。方法：用免疫组化检测１２５例肺癌ｐ５３和ＭＤＭ２蛋白表达，以聚合酶链反应单链构象多态性（ＰＣＲＳＳＣＰ）方法检测ｐ５３基因第５～８外显子的突变。结果：ＰＣＲＳＳＣＰ检测阳性的５２例肺癌ＭＤＭ２阳性率为１９．２％；而阴性的７３例肺癌ＭＤＭ２蛋白阳性率为３５．６％。统计学检验显示肺癌ＭＤＭ２蛋白表达与ｐ５３突变之间呈负相关（χ２＝３．９８，Ｐ＜０．０５）；ＭＤＭ２蛋白阳性与肺癌患者的年龄、性别、肿瘤大小、组织学类型、分化程度、临床分期和ｐ５３蛋白表达无显著相关性。结论：ＭＤＭ２过度表达可能在ｐ５３基因没有突变肺癌的发生过程中起重要作用     

bcl-2、p53和p21基因蛋白在脑星形细胞瘤中的表达及意义

目的：了解抑凋亡基因ｂｃｌ２、抑癌基因ｐ５３和癌基因ｐ２１在脑星形细胞瘤中的存在状况及意义。方法：用ｂｃｌ２、ｐ５３和ｐ２１蛋白抗体对４２例脑星形细胞瘤手术标本进行ＳＰ免疫组化检测，分析表达率与病理分级的关系。结果：良性星形细胞瘤ｂｃｌ２呈现高表达（９０％），恶变后表达下降，良性组表达率不仅显著高于低度恶性组（Ｐ＜０．０１），亦显著高于高度恶性组（Ｐ＜０．０５）；ｐ５３和ｐ２１的表达则随恶性程度增高而呈增高趋势，良性组表达率显著低于低度恶性和高度恶性组（Ｐ＜０．０１）。研究结果提示：星形细胞瘤的发生与ｂｃｌ２、ｐ５３和ｐ２１蛋白的异常表达或突变有关；ｐ５３、ｐ２１和ｂｃｌ２之间可能有互相抑制作用；ｐ５３和ｐ２１表达反映了瘤细胞的分化程度及增殖情况，因而可作为判定脑星形细胞瘤恶性变的指标。     

肺癌MDM2蛋白表达与p53基因突变的关系

目的研究肺癌ＭＩＤ２蛋白表达与ｐ５３突变之间的关系。方法：用免疫组化检测１２５例肺癌ｐ５３和ＭＤＭ２蛋白表达，以聚合酶链反应－单链构象多态性（ＰＣＲ－ＳＳＣＰ）方法检测ｐ５３基因第５￣８外显子的突变。结果：ＰＣＲ－ＳＳＣＰ检测阳性的５２例肺癌ＭＤＭ２阳性率为１９．２％，而阴性的７３例肺癌ＭＤＭ２蛋白阳性率为３５．６％，统计学检验显示肺癌ＭＤＭ２蛋白表达与Ｐ５３突变之间呈负相关（Ｘ＾２＝３．９８，Ｐ     

Western印迹杂交分析p53蛋白在人鼻咽癌中的表达

目的：探讨ｐ５３ 蛋白在人鼻咽癌中的表达及其临床意义。方法：采用Ｗｅｓｔｅｒｎ 印迹法结合免疫沉淀技术,检测鼻咽活检组织ｐ５３ 蛋白表达。结果：１０４ 例鼻咽癌活检组织中,１２ 例（１１．５％ ）ｐ５３ 蛋白突变;８ 例鼻咽慢性炎症活检组织中,ｐ５３ 蛋白表达未见异常。鼻咽癌病人中ＩｇＡ／ＶＣＡ抗体滴度≥１∶１６０ 者ｐ５３ 蛋白突变检出率１１．８％ （１１／９３）,ＩｇＡ／ＶＣＡ 抗体滴度≤１∶８０者,ｐ５３ 蛋白突变检出率９．１ ％ （１／１１） 。ＩｇＡ／ＥＡ 抗体滴度阳性者,ｐ５３ 蛋白突变检出率１４．１％ （１１／７８） ,ＩｇＡ／ＥＡ 抗体滴度阴性者,ｐ５３ 蛋白突变检出率３．８ ％（１／２６） 。ｐ５３ 蛋白表达异常的鼻咽癌病人中,有２ 例复发。结论：鼻咽癌ｐ５３ 蛋白的异常表达多见于恶性程度较高,分期较晚,ＩｇＡ／ＶＣＡ滴度高和ＩｇＡ／ＥＡ阳性的病例,提示ｐ５３ 基因在鼻咽癌中可能发挥一定的作用。     

BCL—2,p53蛋白在乳腺原位癌中的表达

目的：探讨ＢＣＬ－２，ｐ５３蛋白在乳腺原位癌及正常乳腺组织中的表达及相互关系。方法：采用免疫组化检测１５例正常乳腺组织，１０例小叶原位癌及４５例导管原位癌（Ｄｕｃｔａｌ Ｃａｒｃｉｎｏｍａ ｉｎ ｓｉｔｕ，ＤＣＩＳ）。结果：ＢＣＬ－２蛋白在正常乳腺组织及小叶原位癌中的表达均阳性，ｐ５３蛋白均阴性，基因表型呈ＢＣＬ－２＋／ｐ５３－。４５例ＤＣＩＳ中，ＢＣＬ－２蛋白阳性率７７．８％（３５／４５），ｐ３     

MDR1、GST-π、p53、bcl-2在上皮性卵巢癌的表达及意义

目的 探讨ＭＤＲ１、ＧＳＴ－π、ｐ５３、ｂｃｌ－２与上皮性卵巢癌临床病理学特性的关系。方法 采用免疫组化ＳＰ法检测８９例不同性质卵巢组织中ＭＤＲ１、ＧＳＴ－π、ｐ５３、ｂｃｌ－２的表达情况。结果 ①上皮性卵巢癌,交界性肿瘤,良性上皮性肿瘤,正常卵巢组织中四种指标的表达情况：ＭＤＲ１依次为２２／５２（４２．３％）、３／９（３３．３％）、０／２１、０／７、ＧＳＴ－π依次为４３／５２（８２．７％）、５／     

p21、p185、p53蛋白表达对卵巢交界性浆液性肿瘤的鉴别诊断价值

目的： 探讨ｒａｓ、ｃ ｅｒｂＢ ２、ｐ５３ 基因产物ｐ２１ 、ｐ１８５ 、ｐ５３ 蛋白表达对卵巢浆液性肿瘤中良性瘤、交界性瘤和癌的鉴别诊断价值。方法： 采用ＬＳＡＢ免疫组化法。结果：３ 种蛋白在良性瘤、交界性瘤和癌中的单一表达均呈递增趋势,差异显著;联合表达,２ 种以上蛋白同时阳性率后两组高于良性瘤组,差异显著,Ｐ＜ ０００５ ;３ 种蛋白同时阳性率癌组高于前两组,差异显著,Ｐ＜ ００５ 。结论：３ 种蛋白的表达可以作为卵巢浆液性肿瘤中良性瘤、交界性瘤和癌的鉴别诊断的客观指标。     

G1 Arrest and Relative Protein Expressions in Mouse Thymocytes Induced by Whole Body X—Ray Irradiation

Objective:To investigate the molecular regulation of G1 arrest of mouse thymocytes induced by ionizing radiation.Methods:Cell cycle was analyzed by flow cytomtry(FCM)following staining of cells with proidium iodide.Fluorescent staining and flow cytometry analysis were employed for measurement of protein expression.Results:it was demonstrated that G1 phase of mouse thymocytes increased significantly at 12h after whole body irradiation(WBI)with the doses of 0.5,1.0 and 2.0Gy,and at 24h following 2.0Gy exposure,measured by FCM.In the time course experiment,it was found that G1 phase of thymocytes increased significantly at 4h,reached a peak level at 24h and came down toward 48h after WBI with 2.0Gy X-rays.The results also showed that after 2.0Gy exposure,the expression of proteins in mouse thymocytes increased significantlty from 1h to 8h for p53,for p21 from 4h to 48h ,and for MDM2 at 4h and 8h.measured by FCM,But no change was found for GADD45 protein expression.Conclusion;These results suggest that G1 arrest could be induced by a single dose of 0.5Gy,1.0Gy or 2.0Gy,and its molecular control might be established through the p53-p21 pathway.     

G1 Arrest and Relative Protein Expressions in Mouse Thymocytes Induced by Whole Body X-Ray Irradiation G1 Arrest and Relative Protein Expressions in Mouse Thymocytes Induced by Whole Body X-Ray Irradiation

Objective　To investigate the molecular regulation of G1 arrest of mouse thymocytes induced by ionizing radiation. Methods　Cell cycle was analyzed by flow cytometry (FCM) following staining of cells with proidium iodide. Fluorescent staining and flow cytometry analysis were employed for measurement of protein expression. Results　It was demonstrated that G1 phase of mouse thymocytes increased significantly at 12h after whole body irradiation (WBI) with the doses of 0.5, 1.0 and 2.0 Gy, and at 24h following 2.0Gy exposure, measured by FCM. In the time course experiment, it was found that G1 phase of thymocytes increased significantly at 4h, reached a peak level at 24h and came down toward 48h after WBI with 2.0Gy X-rays. The results also showed that after 2.0Gy exposure, the expression of proteins in mouse thymocytes increased significantlty from 1h to 8h for p53, for p21 from 4h to 48h, and for MDM2 at 4h and 8h, measured by FCM. But no change was found for GADD45 protein expression. Conclusion　These results suggest that G1 arrest could be induced by a single dose of 0.5 Gy, 1.0Gy or 2.0Gy, and its molecular control might be established through the p53-p21 pathway.     

Effect of lonizing Radiation on the Expression of p16,CyclinD1 and CDK4 in Mouse Thymocytes and Splenocytes

OBJECTIVE: To investigate the effect of ionizing radiation on the expression of p16, CyclinD1, and CDK4 in mouse thymocytes and splenocytes. METHODS: Fluorescent staining and flow cytometry analysis were employed for the measurement of protein expression. RESULTS: In time course experiments, it was found that the expression of p16 protein was significantly increased at 8, 24, and 48 h for thymocytes (P < 0.05, P < 0.01, and P < 0.05, respectively) and at 24 h for splenocytes (P < 0.05) after whole body irradiation (WBI) with 2.0 Gy X-rays. However, the expression of CDK4 protein was significantly decreased from 8 h to 24 h for thymocytes (P < 0.05-P < 0.01) and from 8 h to 72 h for splenocytes (P < 0.05-P < 0.01). In dose effect experiments, it was found that the expression of p16 protein in thymocytes and splenocytes was significantly increased at 24 h after WBI with 1.0, 2.0, and 4.0 Gy (P < 0.05-P < 0.01), whereas the expression of CDK4 protein was significantly decreased with 2.0 Gy for thymocytes (P < 0.05) and 0.5-6.0 Gy for splenocytes (P < 0.05-P < 0.01). Results also showed that the expression of CyclinD1 protein decreased markedly in both thymocytes and splenocytes after exposure. CONCLUSION: The results indicate that the expression of p16 protein in thymocytes and splenocytes can be induced by ionizing radiation, and the p16-CyclinD1/CDK4 pathway may play an important role for G1 arrest of thymocytes induced by X-rays.     

Effect of Ionizing Radiation on the Expression of p16, CyclinDI and CDK4 in Mouse Thymocytes and Splenocytes

Objective To investigate the effect of ionizing radiation on the expression of p16, CyclinDl, and CDK4 in mouse thymocytes and splenocytes. Methods Fluorescent staining and flow cytometry analysis were employed for the measurement of protein expression. Results In time course experiments, it was found that the expression of p16 protein was significantly increased at 8, 24, and 48 h for thymocytes (P<0.05, P<0.01, and P<0.05, respectively) and at 24 h for splenocytes (P<0.05) after whole body irradiation (WBI) with 2.0 Gy X-rays. However, the expression of CDK4 protein was significantly decreased from 8 h to 24 h for thymocytes (P<0.05,P<0.01) and from 8 h to 72 h for splenocytes (P<0.05-P<0.01). In dose effect experiments, it was found that the expression of p16 protein in thymocytes and splenocytes was significantly increased at 24 h after WBI with 1.0, 2.0, and 4.0 Gy (P<0.05-P<0.01), whereas the expression of CDK4 protein was significantly decreased with 2.0Gy for thymocytes (P<0.05) and 0.5-6.0 Gy f     

宫颈癌中p53、p21WAF1/CIP1、MDM2的表达及其与HPV16感染的关系

目的：探讨子宫颈鳞状细胞癌中p53、p21^WAF1／CIP1、MDM2的表达及其与HPV16感染的关系。方法：采用免疫组化Envision二步法检测p53、p21^WAF1／CIP1及MDM2在43例子宫颈鳞状细胞癌、20例子宫颈上皮内瘤变（CIN）和15例正常对照组中的表达，高危HPV16DNA的检测应用原位杂交法。结果：HPV16、p53、p21^WAF1／CIP1和MDM2在子宫颈癌中的阳性表达率分别为46．51％、34．88％、30．23％、25．58％；在CIN中的阳性表达率分别为45％、5％、60％、15％；HPV16在对照组中的阳性表达率为6．67％，p53、p21^WAF1／CIP1和MDM2未见阳性表达。HPV16、p53、p21^WAF1／CIP1在3种不同组织中表达差异有统计学意义（P〈0．05），MDM2在3种不同组织中表达差异无统计学意义（P〉0．05）。p53、p21^WAF1／CIP1和MDM2在子宫颈癌HPV阳性组和阴性组间表达差异无统计学意义（P〉0．05），p21^WAF1／CIP1蛋白表达与p53有关（P〈0．05），MDM2蛋白表达与p53无关（P〉0．05）。结论：在HPV16感染的子宫颈癌中，p53的转录功能仍然存在。     

MDM2、GADD、p53在子宫内膜增生过长及宫内膜癌中的表达

目的:探讨癌基因 MDM2和抑癌基因 GADD、p5 3与子宫内膜增生过长、子宫内膜癌的关系。方法:应用 MDM2、GADD、p5 3单克隆抗体对 10 0例子宫内膜增生过长、宫内膜癌进行免疫组织化学染色。结果 :MDM2、p5 3在良恶性组间差异有统计学意义 (P <0 .0 5 ) ,而 GADD各组间无差异。 3种基因表达存在相关性 ,MDM2与p5 3呈正相关 ,GADD与 p5 3呈负相关。MDM2与 GADD表达与宫内膜癌的组织分型、分级无关。 结论:MDM2、p5 3参与了子宫内膜癌的发生、发展 ,GADD则间接通过 p5 3而发挥其抑癌功能。     

MDM2、p53和p21WAF1/CIP1蛋白在胃癌中的表达及意义

目的：探讨MDM2在胃癌中的表达情况以及MDM2、p53和p21^WAF1/CIP1在胃癌发生发展中的作用。方法：应用免疫组化SABC法检测94例胃癌MDM2、p53和p21^WAF1/CIP1蛋白的表达情况，并对三者之间的关系及其与胃癌临床病理特征的关系进行统计分析。结果：94例胃癌中未发现有MDM2的表达。p53及p21^WAF1/CIP1的阳性表达率分别为56.38%（53／94）和41.49%（39／94），阳性表达位于癌细胞核。在癌旁不典型增生灶中，p53有3例，p21^WAF1/CIP1有5例阳生，癌旁正常黏膜均为阴性。p53和p21^WAF1/CIP1两者的阳性表达率之间无显著相关性。在性别、年龄、部位、浸润深度、局产淋巴结转移及组织学类型等临床病理指标中，p53或p21^WAF1/CIP1的阳性表达率的差异均无统计学意义。结论：MDM2在胃癌的发展中不起重要作用，而在胃癌发展中起主要作用的是抑癌基因p53的突变。p21^WAF1/CIP、在胃癌中可能是以不依赖p53的途径增高，说明癌细胞增生已不受G1期检查点的控制。     

p53p21MDM2蛋白在卵巢子宫内膜异位症和子宫腺肌症中的表达及意义

目的通过检测p53、p21、MDM2蛋白在正常子宫内膜、卵巢子宫内膜异位症和子宫腺肌症组织中的表达,探讨p53、p21、MDM2基因和细胞凋亡在子宫内膜异位症发生发展中的作用,为临床诊治提供理论依据。方法应用免疫组化染色法(S-P法)检测29例正常子宫内膜、30例卵巢子宫内膜异位症和29例子宫腺肌症组织标本的p53、p21、MDM2表达情况,对p53、p21、MDM2的表达及细胞凋亡之间的关系进行分析。结果 p53蛋白在正常子宫内膜组中分泌期表达高于增生期(P0.05),在卵巢子宫内膜异位症组织和子宫腺肌症组织中增生期与分泌期表达差异无统计学意义(P0.05)。正常子宫内膜组p53蛋白表达率高于卵巢子宫内膜异位症组(P0.05)和子宫腺肌症组(P0.05),差异有统计学意义。卵巢子宫内膜异位症组p53蛋白表达率与子宫腺肌症组相比差异无统计学意义(P0.05)。P21蛋白在正常子宫内膜组的表达率高于卵巢子宫内膜异位症组(P0.05)和子宫腺肌症组(P0.05),差异有统计学意义。卵巢子宫内膜异位症组p21蛋白表达率与子宫腺肌症组相比差异无统计学意义(P0.05)。MDM2蛋白在正常子宫内膜组织的表达率分别低于卵巢子宫内膜异位症组(P0.05)和子宫腺肌症组(P0.05)。卵巢子宫内膜异位症组与子宫腺肌症组相比差异无统计学意义(P0.05)。在卵巢子宫内膜异位症组中p53与p21呈正相关(r=0.611,P0.01),p53与MDM2呈负相关(r=-0.541,P0.01),p21与MDM2在卵巢子宫内膜异位症组中表达无相关性(r=0.404,P0.05)。结论细胞凋亡调控蛋白p53、p21、MDM2与子宫内膜异位症和子宫腺肌症的发生发展相关,子宫内膜异位症和子宫腺肌症发病机制可能存在相同之处。     

细胞周期调节因子在原发和复发鼻咽癌的表达

【目的】探讨细胞周期调节因子在鼻咽癌复发中的作用。【方法】采用LsAB法同时检测69例患者原发和复发鼻咽癌组织中p53、MDM2、p21ras和p21WAF1蛋白的表达。【结果】复发癌与原发癌相比阳性表达率方面,p53蛋白(78%和80%)或MDM2蛋白(84%和83%)很相近,p21ras蛋白(73%和93%)或p21WAF1蛋白(52%和84%)明显下降;高表达率方面,p53蛋白(42%和51%)很相近,MDM2蛋白(57%和32%)明显升高,p21ras蛋白(16%和65%)或p21WAF1蛋白(17%和46%)明显下降。其中,MDM2蛋白表达水平在复发癌明显升高主要见于复发间期<34个月患者组（P<0.05),p21ras蛋白和p21WAF1蛋白表达水平在复发癌明显下降见于复发间期<34个月和≥34个月患者组（均<0.02以下)。【结论】原发鼻咽癌临床治愈后,p53蛋白和MDM2蛋白过度表达以及p21WAF1蛋白低表达或不表达可能仍然对鼻咽癌的复发起重要作用;MDM2蛋白表达水平显著升高和p21WAF1蛋白表达水平显著下降可能进一步加促鼻咽癌的复发过程。     

miR-34a在辐射损伤时对细胞周期的调控作用

目的探讨60Coγ射线诱发大鼠肝脏BRL细胞辐射损伤时p53激活诱导的miR-34a改变对细胞周期的调控作用。方法以大鼠BRL肝细胞为研究对象,予4 Gy60Coγ射线照射后,分别培养4、12、24、48 h。采用流式细胞技术检测各组BRL细胞周期的变化,实时定量PCR检测各组细胞中miR-34a mRNA和c-myc mRNA表达水平的变化,Western blot方法检测各组细胞中p53蛋白和Myc蛋白的表达。结果 60Coγ射线4 Gy照射后4 h即出现G2期阻滞（P〈0.05）,至照射后24 h,G2期阻滞恢复;照射后12 h起,S期细胞减少（P〈0.05）,出现G1阻滞,48 h仍未恢复。照射后4 h p53蛋白和miR-34a mRNA表达增加（P〈0.05）,12 h均有下降（P〈0.05）,24 h和48 h已基本回至正常水平,而c-myc在照射后4 h开始呈持续降低趋势,48 h有所恢复。结论细胞在电离辐射引起DNA损伤后,早期即激活了p53蛋白,p53蛋白调节miR-34a表达,可能再经由miR-34a的靶基因c-myc介导,使细胞阻滞于G1和（或）G2期进行DNA修复。