免疫组化和PCR—SSCP检测p53基因异常的一致性探讨

目的：探讨免疫组化检测ｐ５３蛋白表达和ＰＣＲ－ＳＳＣＰ检测ｐ５３基因突变的一致性。方法：单克隆抗体ＤＯ－７检测８５例非小细胞肺癌（ＮＳＣＬＣ）的ｐ５３蛋白表达，ＰＣＲ－ＳＳＣＰ检测其中３１例腺癌的ｐ５３基因突变。结果：８５例ＮＳＣＬＣ中ｐ５３蛋白表达阳性率为６８％（５８／８５），３１例腺癌中ｐ５３蛋白表达阳性率为６１％（１９／３１），１４例（４６％）出现ｐ５３基因５～８外显子突变，ｐ５３蛋白免疫组化和ＰＣＲ－ＳＳＣＰ检测ｐ５３基因突变无显著相关（χ２＝０．１，Ｐ＝０．７６），其一致率为５２％。结论：ｐ５３蛋白表达并不能很好地反映ｐ５３基因突变。     

星形细胞肿瘤中MDM2蛋白与突变型p53蛋白的表达及其？…

目的：探讨ｍｄｍ－２基因表达和ｐ５３基因突变在星形细胞肿瘤发生发展中的作用及两者的相关性。方法：采用ＳＡＢＣ免疫组化法对１２０例星形细胞肿瘤进行检测。结果：在分化不良性星形细胞瘤及多形性胶质母细胞瘤中，ＭＤＭ２蛋白的阳性率分别为３０．００％和３５．２９％，突变型ｐ５３蛋白的阳性率分别为３５．００％和４４．１２％，均明于高于高分化星形细胞瘤（４．３５％和６．５２％）；突变型ｐ５３蛋白染色阴性的星形细     

星形细胞肿瘤中MDM2蛋白与突变型p53蛋白的表达及其相关性研究

目的：探讨ｍｄｍ－２基因表达和ｐ５３基因突变在星形细胞肿瘤发生发展中的作用及两者的相关性。方法：采用ＳＡＢＣ免疫组化法对１２０例星形细胞肿瘤进行检测。结果：在分化不良性星形细胞瘤及多形性胶质母细胞瘤中，ＭＤＭ２蛋白的阳性率分别为３０．００％和３５．２９％，突变型ｐ５３蛋白的阳性率分别为３５．００％和４４．１２％，均明显高于高分化星形细胞瘤（４．３５％和６．５２％）；突变型ｐ５３蛋白染色阴性的星形细胞肿瘤中，ＭＤＭ２蛋白阳性率（２６．１５％）明显高于其染色阳性的肿瘤（９．３８％）。结论：ＭＤＭ２蛋白及突变型ｐ５３蛋白在星形细胞肿瘤中的表达均与该肿瘤的分化程度有关；ｍｄｍ－２基因扩增及产物ＭＤＭ２蛋白过度表达，可能是突变型ｐ５３蛋白染色阴性的星形细胞肿瘤发生的分子基础     

肺癌p53蛋白表达和基因突变与临床病理的相关研究

目的 检测肺癌中ｐ５３蛋白表达和基因突变状况及其与临床病理和预后的相关性。方法：应用免疫组织化学（ＬＳＡＢ法）和聚合酶链反应－单链构象多态性分析（ＰＣＲ－ＳＳＣＰ）二种方法。结果 检测肺鳞癌４６例，共９５例。免疫组化ｐ５３蛋白总阳性率为５０．５％（４８／９５例），肺鳞癌阳性率为５６．５％（２６／４６例）、肺腺癌为４４．７％（２２／４９例）。ＰＣＲ－ＳＳＣＰ检测ｐ５３基因突变率为４１．１％（３９／９     

bcl-2、p53蛋白及PCNA表达与横纹肌肉瘤临床病理相关性研究

目的：研究横纹肌肉瘤（ＲＭＳ）中ｂｃｌ－２、ｐ５３、ＰＣＮＡ表达与其临床病理的相关性。方法：对５０例（随访４１例）横纹肌肉瘤进行免疫组化ＡＢＣ法标记。结果：ｂｃｌ－２、ｐ５３基因蛋白和ＰＣＮＡ，发现ｂｃｌ－２、ｐ５３、ＰＣＮＡ阳性表达率分别为２８％、７２％、７０％，其阳性表达与年龄、性别及不同组织类型的ＲＭＳ无关（Ｐ＞０．０５）。但与分化程度有关，ｐ５３、ＰＣＮＡ在低分化ＲＭＳ阳性率分别为８５％、９５％，显著高于高分化ＲＭＳ４２．８％和１４．３％（Ｐ＜０．０５），随访存活１年以内的ｐ５３、ＰＣＮＡ阳性率均为８６．７％，亦明显高于存活超过３年以上的阳性率３３．３％和４１．７％（Ｐ＜０．０５）。而ｂｃｌ－２在低分化ＲＭＳ阳性２０％显著低于高分化７１．４％（Ｐ＜０．０５），随访存活１年以内的阳性率１３．４％明显低于存活超过３年以上的４１．４％（Ｐ＜０．０５）。ｐ５３与ｂｃｌ－２阳性表达呈明显负相关，ｐ５３阳性率越高，而ｂｃｌ－２阳性率越低。结论：ＰＣＮＡ、ｐ５３、ｂｃｌ－２蛋白表达能比较准确地反映ＲＭＳ的生物学特性，ｐ５３、ｂｃｌ－２可作为肿瘤预后显著相关的有效指标。     

骨肉瘤N—ras,c—myc基因异常及其蛋白产物的表达

目的：探讨癌基因Ｎ－ｒａｓ，ｃ－ｍｙｃ及其蛋白表达与骨肉瘤的关系，方法：Ｓｏｕｔｈｅｒｎｂｌｏｔ和免疫组织化学（ＬＳＡＢ法）同步检查９例人骨肉瘤Ｎ－ｒａｓ，ｃ－ｍｙｃ癌基因和其ｐ２１ｒａｓｃ－ｍｙｃ蛋白产物表达，结果：Ｎ－ｒａｓ基因１例有为失改变，检出率１１％（１／９），ｃ－ｍｙｃ基因有３例为扩增改变，检出率３３％（３／９），ｐ２１ｒａｓ，ｃ－ｍｙｃ基因蛋白表达阳性率分别为７８％（７例），８９％（     

c─erbB─2、ras p21及p53在大肠癌表达的免疫组化研究

对４８例大肠癌连续切片进行ｃ─ｅｒｂＢ─２、ｒａｓｐ２１及ｐ５３３种癌相关基因产物的免疫组化ＡＢＣ法及ＡＰＡＡＰ－ＩＧＳＳ双重标记研究，结果表明：（１）癌相关基因ｃ─ｅｒｂＢ─２、ｒａｓｐ２１和ｐ５３阳性表达率在癌组织分别为５０．２％（２５／４８）、４３．８％（２１／４８）和５４．２％（２６／４８）；癌旁粘膜分别为２５％（１２／４８）、１８．８（９／４８）和２０．８％（１０／４８）；而在＂正常＂结肠粘膜则分别为１２．５％（６／４８）、６．３％（３／４８）和０．（２）有２种以上癌相关基因产物同时表达者在癌组织中有２６例（５４．２％）．在癌旁粘膜有５例（１０．５％），而在正常粘膜则未见有２种癌相关基因同时表达，（３）癌组织中ｃ─ｅｒｂＢ─２＋ｐ２１、ｃ─ｅｒｂＢ─２＋ｐ５３、ｐ２１＋ｐ５３及ｃ─ｅｒｂＢ─２＋ｐ２１＋ｐ５３同时表达者分别为２．１％、１２．５％、１６．７％及２２．９％，（４）ＡＰＡＡＰ－ＩＧＳＳ双重免疫标记结果表明，单一癌细胞可同时表达２种癌基因产物。上述结果提示：ｃ─ｅｒｂＢ─２、ｒａｓｐ２１及ｐ５３可能与大肠病的发生有关，三者在大肠病的发生中可能起协同作用。     

SLE病人外周血Bcl—2／JH基因重排检测的意义

应用聚合酶链反应（ＰＣＲ）方法检测３１例ＳＬＥ病人外周血单个核细胞（ＰＢＭＣ）Ｂｃｌ－２／ＪＨ基因重排现象和流式细胞仪间接双标记法分析其Ｔ（ＣＤ３）、Ｂ（ＣＤ１９）细胞Ｂｃｌ－２蛋白的表达。结果显示，ＳＬＥ病人Ｔ细胞Ｂｃｌ－２蛋白表达明显高于正常人（４２．９５％±２８．４７％对比９．９４％±４．９６％，Ｐ＝０．０００４），尤其以活动期ＳＬＥ病人为明显，而Ｂ细胞Ｂｃｌ－２蛋白表达与正常人之间并无统计学差异（７９．２１％±１０．６９％对比８１．９６％±６．９７％；Ｐ＝０．４６０２）。７例ＳＬＥ病人具有典型的Ｂｃｌ－２／ＪＨ基因重排（占２２．５８％），且均为ＳＬＥ活动期病人，其Ｔ细胞Ｂｃｌ－２蛋白表达明显高于无基因重排的ＳＬＥ病人，其Ｂ细胞Ｂｃｌ－２表达并无差异（Ｐ＞０．３９０５）。说明Ｂｃｌ－２／ＪＨ基因重排现象可见于ＳＬＥ，并与Ｔ细胞Ｂｃｌ－２蛋白高表达有关，表明细胞凋亡抑制基因Ｂｃｌ－２在ＳＬＥ发病机制中具有重要作用。     

p-MAPK、cyclinD1和p53蛋白在大肠癌中的表达及其相关性

目的：检测ｐ－ＭＡＰＫ、ｃｙｃｌｉｎＤ１和ｐ５３蛋白在大肠癌中的表达，并探讨其相关性。方法：免疫组织化学Ｓ－Ｐ法。结果：１４０例大肠癌中ｐ－ＭＡＰＫ、ｃｙｃｌｉｎＤ１和ｐ５３蛋白的阳性表达率分别为９２．９％（１３０／１４０）、８７．１％（１２２／１４０）和６６．４％（９３／１４０）；５０例相应癌旁肠粘膜中阳性表达率分别为４．０％（２／５０）、６．０％（３／５０）和２．０％（１／５０）。三者阳性表达     

肝癌组织中N—ras基因突变和p53蛋白表达

目的：研究Ｎ－ｒａｓ和ｐ５３基因与肝癌发生，发展的关系。方法：应用多聚酶链反应－单链构象多态性分析法（ＰＣＲ－ＳＳＣＰ）和免疫组化法，检测２９例肝癌中的Ｎ－ｒａｓ基因突变和ｐ５３蛋白的表达。结果，１３例肝癌ｐ５３蛋白阳性（４４．８％），表明广西地区肝癌中曾普遍存在ｐ５３基因的突变，肝癌及癌旁组织中Ｎ－ｒａｓ基因在第２～３７密码子间的突变率分别为７９．３１％和８０．７７％，２２例有２个以上突变位点（     

Analysis of p53 and mdm2 proteins in malignant fibrous histiocytoma in absence of gene alteration: prognostic significance

TP53 and MDM2 genes and their protein expression were evaluated in frozen and paraffin-embedded tissue from 27 patients with malignant fibrous histiocytoma to elucidate the relationship between them, their implication in tumor progression mechanisms and their possible diagnostic-prognostic value in malignant fibrous histiocytoma. Single-strand conformation polymorphism analysis and direct sequencing of polymerase chain reaction-amplified DNA were used to establish two TP53 mutations (7.4%): a point mutation and a 63-bp duplication. Amplification of the MDM2 gene was observed in two tumors (7.4%) by means of Southern-blot analysis, one of them also carrying the TP53 point mutation. Immunohistochemical and Western-blot techniques were used to study nuclear accumulation of p53 and mdm2 proteins: 11 cases (40.7%) with p53 protein expression and thirteen cases (48.1%) with mdm2 protein expression were detected. We confirmed overexpression of mdm2 protein in eight of ten cases (80%) with p53 protein expression without TP53 gene mutation. Statistical analysis shows that simultaneous co-expression of p53 and mdm2 in malignant fibrous histiocytoma is significantly correlated with survival in absence of gene alteration in contrast to the lack of statistical correlation with survival of p53 protein expression alone. Received: 13 April 1999 / Accepted: 14 July 1999     

Pitfalls in the diagnosis of ectopic hamartomatous thymoma

We have investigated the immunohistochemical expression of p53, mdm2, p21/waf1 and bcl-2 proteins in 31 thymic epithelial tumours comprising five medullary thymomas (MDT), four mixed thymomas (MT), 12 cortical thymomas (CT), eight predominately cortical thymomas (PCT) and two well-differentiated thymic carcinomas (WDTC). We have found p53, mdm2, p21 and bcl-2 protein expression in 25/31, 8/31, 5/31 and 10/31 thymic epithelial tumours, respectively. Coexpression of p53 and mdm2 proteins was found in eight cases (three CT, four PCT and one WDTC). Five of them were also p21 positive and three p21 negative. Discordant p53+/mdm2−/p21− protein expression was found in 19 cases (three MDT, three MT, nine CT, three PCT and one WDTC). Mdm2 and p21 proteins were not expressed in the absence of p53 protein. Coexpression of bcl-2 and p53 proteins was found in seven cases (three MDT, three MT and one WDTC). Eighteen cases were p53+/bcl-2− (10 CT, seven PCT and one WDTC) and three cases (two MDT and one MT) were bcl-2+/p53−. Our findings indicate that in thymomas, p53 expression is more frequently associated with cortical histotypes while bcl-2 expression is strongly associated with medullary and mixed histotypes. In addition, there is an inverse correlation between p53 and bcl-2 protein expression in thymomas. Coexpression of p53/mdm2/p21 proteins may reflect thymomas with wild-type (wt), p53 gene since mdm2 and p21 proteins are inducible by wt p53 gene. However, in view of previous findings that p53 mutation is an early event in thymomas, the possibility of p53 gene mutation with p53-independent mdm2 and p21 expression should be considered in these cases. Discordant p53+/mdm2−/p21− protein expression may represent thymomas with p53 gene mutations unable to activate expression of mdm2 and p21 proteins.     

Human papillomavirus infection in Egyptian esophageal carcinoma: correlation with p53, p21, mdm2, C-erbB2 and impact on survival

The etiological role of human papillomavirus (HPV) in esophageal carcinoma (EC) in relation to p53, mdm2, p21(waf), c-erbB2 and the overall survival (OS) rate was investigated. Tumor and normal tissues from 50 EC were evaluated by polymerase chain reaction and InnoLiPA for HPV. Single strand conformation polymorphism/sequencing were used to detect p53 gene mutations. Immunohistochemistry was performed to determine p53, mdm2, p21(waf)and c-erbB2 expression. Human papillomavirus was detected in 54% of tumors and in 24% of normal tissues. p53, mdm2 and c-erbB2 overexpression was detected in 68%, 70% and 60% of tumors and in 14%, 16% and 10% of normal samples, whereas loss of p21(waf) was evident in 64% of tumors. p53 mutations were detected in 20% of cases. Exon 8 and 5 showed the highest mutation rate (40% each), followed by exons 6 and 7 (10% each). There was a significant correlation between HPV and p53, mdm2, c-erbB2 overexpression. The OS was significantly associated with overexpression of p53 and loss of p21(waf). Human papillomavirus infection is frequent in Egyptian EC. Both p53-dependent and p53-independent pathways seem to be involved in HPV-associated EC. mdm2 and c-erbB2 are possible targets for HPV in the p53-independent pathway. However, only advanced stage and aberrant expression of p53 and p21(waf) are independent prognostic markers.     

Immunohistochemical detection of p53, mdm2, waf1/p21, and Ki67 proteins in bone marrow biopsies in myelodysplastic syndroms, acute myelogenous leukaemias and chronic myeloproliferative disorders

The aim oof this study was to investigate the immunohistochemical expression of p53, mdm2, and waf1/p21 proteins in myelodysplastic syndromes (MDS), acute myelogenous leukaemias (AML), and chronic myeloproliferative disorders (CMPD). Paraffin-sections of bone marrow biopsies from 30 cases of MDS (6 cases of RAEB and RAEB-T) 22 AML (4 cases occurring in the setting of MDS), 16 chronic myeloproliferative disorders (CMPD), and 10 cases without alterations were investigated by immunohistochemistry for p53, waf1/p21, mdm2 and Ki67 proteins. P53 was detected in immature myeloid cells in 6/30 MDS (20%) and in 6/22 AML (27%) while it was not expressed in CMPD. Of the 6 p53 positive AML, 3 occurred as evolution of MDS and 3 were de novo acute leukaemias. Waf1/p21 was detected in 5/22 (23%) AML in immature myeloid cells. Waf1/p21 was also expressed in 18/30 (60%) MDS and 10/16 (63%) CMPD in variable proportion (5-25%) of the mature myeloid cells and megakaryocytes. Waf1/p21 was not detected in immature myeloid cells in MDS and CMPD. Mdm2 protein was expressed in 3/30 (10%) MDS in the immature myeloid cells and in 1/22 AML in blastic cells. The combined immunophenotypes of immature myeloid cells of MDS were: p53+/mdm2+/waf1-: 3, p53+/mdm2-/waf1-: 3, while the immunohistochemical patterns of AML were: p53+/mdm2-/waf1-: 4, p53+/mdm2+/waf1+: 1, p53+/mdm2-/waf1+: 1, p53-/mdm2-/waf1+: 3. Ki67/MIB1 staining was found in at least 30% of immature myeloid cells in MDS and AML and in at least 20% of these cells in CMPD. In conclusion, our results indicate that p53 protein is overexpressed in the myeloid lineage in a proportion of AML and MDS, while is not detected in CMPD and normal bone marrow, p53 expression was much more frequent in AML occurring as an evolution of MDS than in de novo AML. The combined immunophenotypes of p53 positive AML and MDS suggest that p53 overexpression may be due to mutation, in some AML and MDS cases with the p53+/mdm2-/waf1- phenotype. However, it would be also possible that p53 protein accumulation is not related to p53 mutation but to inhibition of p53/mdm2 binding due to mdm2 defects and/or other events related to cell stress signals. On the other hand, waf1/p21 protein overexpression without p53 expression in some AML could be p53-independent and may represent an attempt to control the high proliferation rate which was evidenced by Ki67/MIB1 immunostaining. However, the possibility of p21 to arrest cell-cycle, in these cases of AML, seems to be overridden, suggesting that cell-cycle deregulation may be involved in a proportion of AML.     

胰腺癌p53上下游基因mdm2、p21WAF/CIP1以及P14ARF蛋白的表达及相互关系

目的 探讨p14ARF、p53、mdm2及p21WAF/CIP1蛋白在胰腺癌组织中的表达、相互关系及意义。方法 选取167例胰腺癌、101例癌旁与13例良性病变组织构建组织芯片(又称组织微阵列),应用免疫组织化学EnVision二步法检测这4种蛋白在胰腺良恶性病变中的表达。结果 p14ARF、p53、mdm12及p21WAF/CIP1在胰腺癌中表达的阳性率分别为35.3％(59/167)、57.5％(96/167)、64.1％(107/167)和39.5％(66/167)。同癌旁组织相比,p53和mdm2表达明显升高(P<0.01),而p14ARF和p21WAF/CIP1的表达明显降低(P<0.05)。p21WAF/CIP1的阳性表达与年龄、神经受累显著相关(P<0.05);p53的阳性表达与肿瘤的分化、淋巴结转移和神经受累均显著相关(P<0.05);mdm2的阳性表达与肿瘤的分化显著相关(P<0.05);p14ARF与年龄和浸润转移显著相关(P<0.05)。四者阳性表达两两之间统计学上具有关联性(P<0.05)。结论 p53和mdm2的过表达以及p14ARF和p21WAF/CIP1的缺失表达可能会导致胰腺癌的形成和进展;4种蛋白主要以p14ARF-p53-mdm2-p21WAF/CIP1通路的方式作用于细胞的转化和肿瘤的形成;联合检测p53和mdm2的表达可用于评定胰腺癌的恶性程度。     

胃癌及胃液中p53、ras基因突变与临床病理的关系

目的：探讨胃良性病变向恶性转化过程中p53、ras基因突变的规律，并分析胃癌无损伤基因检测的可行性。方法：应用PCR－SSCP及免疫组织化学方法对比研究。结果：异型增生p53基因突变率10％（3／30）、ras基因突变率10％（3／30）、ras基因突变率16．7％（5／30）（二者总突变率26．7％）；早期胃癌p53基因突变率35％（7／20）、ras基因突变率60％（12／20）（二者总突变率85％，其中2例重复突变）； 中晚期胃癌p53基因突变率60％（18／30）、ras基因突变率43．3％（13／30）（二者总突变率90％，其中4例重复突变）；胃息肉ras基因突变仅1／10。30例胃溃疡边缘正常黏膜均未发现p53、ras基因突变。p53基因突变的25例胃癌的胃液中其相应的突变率32％（8／25）。19例胃癌患者的胃液中9例有ras基因突变47．1％（9／19）。异型增生p53蛋白过度表达阳性率13．3％（4／30),p^21ras蛋白阳性率16．7％（5／30）。胃癌p53蛋白阳性率56％（28／50），p^21ras蛋白阳性率60％（30／50）。正常胃黏膜上皮、溃疡边缘正常黏膜及胃息肉均呈p53及ras蛋白阴性表达。结论：胃癌的发生发展与癌基因ras与抑癌基因p53的突变有关，且两种基因同时检测，可覆盖绝大多数胃癌病例，提高了本项技术的可靠性，提供了胃癌无损伤基因检测的可行性的实验证据。     

Methylation of p14(ARF) gene in meningiomas and its correlation to the p53 expression and mutation.

We have previously reported the statistically significant correlation of immunohistochemical expression of MIB-1 and p53 proteins among benign, atypical, and anaplastic meningiomas and p53 protein expression was high in atypical and anaplastic meningiomas. In the present study, we analyzed 22 cases of meningiomas for mutation of p53 gene in its spectrum of exon 5 to 8 using automated genetic analyzer. We did not find any mutation of p53 in any of these cases, thus suggesting the p53 protein expression is wild type. We analyzed 72 cases of meningiomas for determining the methylation status of p14(ARF) gene and the immunohistochemical expression of MDM2 protein to explain p53 protein expression in these meningiomas. We found methylation of p14(ARF) gene in five of 58 cases of benign meningiomas (8.6%), two of 10 cases of atypical meningiomas (20%), and two of four cases of anaplastic meningiomas (50%). In absence of p53 gene mutation, the high percentage of p14(ARF) gene methylation in high-grade meningioma may have been responsible for accumulation of wild-type p53 protein. In addition, we also found the loss of MDM2 protein in high-grade meningiomas. These deregulations of p14-MDM2-p53 pathway may contribute to the malignant progression of meningioma.     

Distinction between lipoma and liposarcoma by MDM2 alterations: a case report of simultaneously occurring tumors and review of the literature

We investigated a lipoma and a well-differentiated/dedifferentiated liposarcoma (WD/DDL), occurring simultaneously in one patient for the possible role of p53 and mdm2 in the molecular oncogenesis of liposarcoma and tumor progression. The hypothesis tested was if there is a continuum in the development from lipoma to liposarcoma. Lipoma was characterized by a lack of p53 mutation, p53 LOH and p53 protein expression, as well as by mdm2 amplification and mdm2 protein expression. p53 mutation and p53 LOH were found neither in the well-differentiated nor in the dedifferentiated parts of the liposarcoma. In contrast, mdm2 amplification and an increase in mdm2 protein expression were found to be associated with malignancy and dedifferentiation, whereas p53 protein expression was only slightly increased. These findings indicate that mdm2 constitutes one of the most common targets for molecular aberration in WD/DDL. We suggest that mdm2 is a marker distinguishing between ordinary lipoma and well-differentiated liposarcoma, and that the genesis of these tumors is different.