胃癌p53基因表达与转移及预后的研究

目的观察胃癌组织ｐ５３基因的超表达及其与预后的关系。方法用抗人Ｐ５３基因蛋白单克隆抗体Ｓ＿Ｐ免疫组织化学方法，观察１２８例胃癌组织ｐ５３表达状况，并对ｐ５３表达与胃癌淋巴结转移状态和术后５年生存率进行比较分析。结果胃癌组织１２８例的ｐ５３表达阳性率为４３８％（５６／１２８）；ｐ５３表达阳性和阴性组的胃癌局部和远处淋巴结转移率分别为６７９％（３８／５６）和５１４％（３７／７２），两者经统计学处理无显著性差异（Ｐ＞００５）。获得随访９８例，胃癌术后５年生存率的随访结果显示，ｐ５３阳性和阴性组分别为３８１％（１６／４２）和３０１％（１７／５６），两组间无统计学意义（Ｐ＞００５）。结论胃癌的发生与ｐ５３基因突变关系密切，并可用免疫组化检测，但Ｐ５３基因蛋白在胃癌组织中的超表达，似不能作为判断胃癌预后的参考指标，应进一步探讨     

大肠良恶性病变p53基因表达及意义

目的研究抗癌基因Ｐ５３蛋白在大肠良、恶性病变组织中的表达情况，探讨Ｐ５３蛋白表达与大肠癌临床病理因素的关系．方法应用免疫组织化学ＳＰ法检测了１４６例良恶性大肠病变组织中Ｐ５３蛋白水平．结果正常大肠粘膜及非肿瘤性息肉Ｐ５３蛋白均阴性，而１１例腺瘤，５３例癌旁粘膜及７６例癌组织中ｐ５３阳性率分别为１８１８％（２／１１），１３２１％（７／５３）及４２１１％（３２／７６）．在腺瘤及癌旁粘膜组织中，仅有散在细胞核里ｐ５３阳性，但在３２例ｐ５３阳性大肠癌中，７５％呈现（＋＋）或（＋＋＋）的阳性表达．在各组织类型癌中，以低分化腺癌与粘液癌ｐ５３阳性率最高，分别为６３６４％（７／１１）及６２５％（１０／１６），显著高于高中分化腺癌的３０１６％（１５／４０）（Ｐ＜００５），并且ｐ５３阳性大肠癌比ｐ５３阳性癌更容易穿透肠壁侵犯浆膜及浆膜外组织，其淋巴结转移率也明显高于ｐ５３阴性者（Ｐ＜００５）．但Ｐ５３蛋白表达与肿瘤大小，肉眼类型，部位，Ｄｕｋｅｓ分期及术后３年生存率无关．结论ｐ５３基因突变或过表达是大肠肿瘤发生过程中的重要因素，并可能与肿瘤进展及转移有关．     

p53 C-myc和P-gp蛋白在胃癌细胞中表达

目的研究胃癌组织中ｐ５３和Ｃｍｙｃ的表达与多药耐药性（ＭＤＲ）的关系．方法应用ＬＳＡＢ免疫组织化学方法研究６７例（男４１例，女２６例，平均年龄４６±１５８岁）胃癌标本中ｐ５３，Ｃｍｙｃ和Ｐｇｐ的表达．结果本组胃癌中ｐ５３阳性３２例（４７８％），Ｃｍｙｃ阳性３７例（５５２％），Ｐｇｐ阳性３９例（５８２％）．淋巴结转移阳性胃癌ｐ５３阳性率（５６９％）和Ｃｍｙｃ阳性率（６４７％）显著高于淋巴结转移阴性的胃癌（Ｐ＜００５）．ｐ５３的异常表达与ｍｄｒ１基因表达呈显著正相关（ｒ＝０６３，Ｐ＜００５），而Ｃｍｙｃ和ｍｄｒ１的表达无明显相关．结论ｐ５３异常表达可增加ｍｄｒ１基因的表达，从而使胃癌细胞获得ＭＤＲ表型     

原位杂交方法检测胃癌及其癌前病变中抑癌基因p53的表达

目的用原位杂交方法检测胃粘膜癌前病变及胃癌组织中ｐ５３ｍＲＮＡ的表达,并观察感染Ｈｐ对其表达的影响．方法病理证实为慢性胃炎６６例和胃癌１６例,用地高辛标记的ｃＤＮＡ为探针进行原位杂交实验,检测其胃粘膜组织中ｐ５３ｍＲＮＡ表达,用单克隆抗体ＤＯ０１进行免疫组化检测Ｐ５３蛋白的表达．结果在慢性萎缩性胃炎、肠化生、异型增生及胃癌中,原位杂交方法检测ｐ５３ｍＲＮＡ表达率分别为５３９％,５２３％,４２８％和２５％,免疫组化方法检测Ｐ５３蛋白的表达率分别为００％,５３％,１５４％和２５％．ｐ５３ｍＲＮＡ的表达与蛋白的表达无明显的一致性,ｐ５３ｍＲＮＡ的表达可以在Ｐ５３蛋白阴性及阳性的细胞中．在２６例萎缩性胃炎中,１４例检测到ｐ５３ｍＲＮＡ的表达,而其中１６例（包括１４例阳性病例）无一例检测到Ｐ５３蛋白的表达．在肠化生、异型增生及胃癌组织中也发现有类似的情况．Ｈｐ感染组与未感染组,ｐ５３ｍＲＮＡ表达率之间统计学检验Ｐ＜００５．结论在胃癌及其癌前病变中,随着病变的发展,ｐ５３ｍＲＮＡ的表达率随之下降,Ｈｐ对其表达有明显的影响     

胃粘膜p53抑癌基因异常与癌变的研究

目的系统研究各种胃粘膜病变中ｐ５３抑癌基因的变异和意义．方法内镜活检组织１５４例，其中浅表性胃炎３０例，萎缩性胃炎３３例，萎缩性胃炎伴肠上皮化生３１例，萎缩性胃炎伴异型增生３０例，胃腺癌３０例．用免疫组化法检测Ｐ５３蛋白表达；用单链构象多态性分析及ＤＮＡ测序检测ｐ５３第５～８外显子点突变．结果胃良性病变粘膜未见Ｐ５３蛋白表达．胃癌中Ｐ５３蛋白阳性表达率为３３３％（１０／３０例）．单链构象多态性分析ｐ５３点突变的检出率，在胃癌为５４５％（６／１１例），异型增生为２０％（３／１５例），肠化生为６７％（１／１５例），测序证实１例胃癌在第５外显子存在点错义突变和碱基缺失，２例异型增生在第６外显子存在点错义突变．结论ｐ５３抑癌基因变异与胃粘膜癌变有关．     

胃癌组织P16，P53蛋白和增殖细胞核抗原的表达意义

目的探讨Ｐ１６,Ｐ５３蛋白和增殖细胞核抗原（ｐｒｏｌｉｆｅｒａｔｉｎｇｃｅｌｎｕｃｌｅａｒａｎｔｉｇｅｎ,ＰＣＮＡ）在胃癌的发生、发展中的作用及临床意义．方法应用免疫组织化学方法,对７７例胃癌和癌旁粘膜组织、２１例胃正常组织中Ｐ１６,Ｐ５３蛋白表达产物和ＰＣＮＡ进行检测,并结合临床资料进行分析．结果胃癌组织中Ｐ１６蛋白的阳性率为２０８％（１６／７７）,明显低于癌旁粘膜组织５９７％（４６／７７）和胃正常组织９０５％（１９／２１,Ｐ＜００５）;Ｐ５３蛋白与ＰＣＮＡ在胃癌组织中的阳性率为８０５％（６２／７７）和９２２％（７１／７７）,明显高于癌旁粘膜组织４１６％（３２／７７）,６４９％（５０／７７）和胃正常组织００％（０／２１,Ｐ＜００５）．Ｐ１６,Ｐ５３蛋白和ＰＣＮＡ阳性表达与胃癌组织学类型、浸润深度、分化程度及淋巴结转移有显著性差异（Ｐ＜００５）,与患者年龄、性别、肿瘤大小及部位无关（Ｐ＞００１）．结论Ｐ１６,Ｐ５３蛋白和ＰＣＮＡ的异常表达对胃癌的发生发展、恶性程度、淋巴结转移及预后有密切关系和重要临床意义．     

C-myc,Bcl-2与胃癌生物学行为和细胞凋亡

目的探讨癌基因Ｂｃｌ２，Ｃｍｙｃ的表达变化与胃癌生物学行为和细胞凋亡的关系．方法采用免疫组化ＬＳＡＢ法，检测６０例原发性胃癌组织（男３８例，女２２例，年龄３７岁～７５岁）癌基因Ｂｃｌ２，Ｃｍｙｃ蛋白的表达变化；在普通光学显微镜下对受检组织的ＨＥ片进行形态学测量和凋亡细胞计数．结果受检组织６０例中，Ｃｍｙｃ阳性表达３７例（６２％），其表达与分化程度和临床分期呈显著性相关，且Ｃｍｙｃ阳性组织细胞凋亡指数（０７±０３）明显高于阴性组织（０３±０２）；所检标本中，Ｂｃｌ２阳性表达率为６８％（４１／６０），其中高分化胃癌的阳性表达率明显高于低分化胃癌（３２％ｖｓ９％）（Ｐ＜００５），阳性Ｂｃｌ２组织与阴性Ｂｃｌ２组织比较，前者凋亡指数明显低于后者（０４±０３ｖｓ０９±０５）（Ｐ＜００５）．结论Ｃｍｙｃ与Ｂｃｌ２基因的异常表达是胃癌生物学行为的重要影响因素，二者在胃癌形成过程中均起着一定的作用，并对细胞增生与凋亡有重要调节作用．     

大肠癌P53蛋白PCNA和CEA的表达与淋巴结转移的关系

目的研究大肠癌Ｐ５３蛋白、增殖细胞核抗原（ＰＣＮＡ）和ＣＥＡ的表达与淋巴结转移的关系．方法应用链霉菌素生物素（ＳＰ）免疫组化法，观察４４例大肠癌Ｐ５３，ＰＣＮＡ的阳性率和ＣＥＡ的表达型式．结果大肠癌Ｐ５３阳性率为５２３％；大肠癌Ｐ５３阳性表达与性别、年龄及肿瘤的部位、分化程度和浸润深度无关（Ｐ＞００５）；大肠癌Ｐ５３阳性者其淋巴结转移率较阴性者高（１４／２３，６０９％ｖｓ６／２１，２８６％，Ｐ＜００５）；Ｐ５３阳性表达及有淋巴结转移者其细胞增殖活性分别较Ｐ５３阴性表达及无淋巴结转移者高（５５９±１７ｖｓ３７９±１４，Ｐ＜００５；５６２±１５ｖｓ３９６±１７，Ｐ＜００５）；Ｐ５３阳性表达及有淋巴结转移者其ＣＥＡ表型均以胞质型和间质型为主（２１／２３，９１３％ｖｓ１３／２１，６１９％，Ｐ＜００５；１９／２０，９５０％ｖｓ１５／２４，６２５％，Ｐ＜００５）．结论检测Ｐ５３和ＰＣＮＡ表达及ＣＥＡ表型对判断大肠癌的恶性程度，预测其淋巴结转移趋势和预后及指导临床治疗有重要价值．     

胃癌癌旁组织中p53、p16和bcl-2蛋白表达及其关系的探讨

目的：研究胃癌癌旁组织中抑癌基因和抗凋亡基因蛋白的表达及其内在关系。方法：胃镜及外科手术中取４０例 胃癌患者的癌组织和癌旁组织各两块,石蜡包埋,切片ＨＥ染色作病理及免疫组织化学检查ｐ５３、ｐ１６和ｂｃｌ－２基因蛋 白表达。结果：ｐ５３在胃癌组织中阳性表达率４２．５％,癌旁组织１２．５％,有显著性差异（Ｐ＜０．０１）,其表达强度也有显著 性差异（Ｐ＜０．０１）;ｐ１６在癌旁组织阳性表达率为６０％,显著高于胃癌组织３７．５％（Ｐ＜０．０５）,其表达强度也有显著性差 异（Ｐ＜０．０５）;ｂｃｌ－２在胃癌组织和癌旁组织阳性表达率无显著性差异（６７．５％比４７．５％,Ｐ＞０．０５）,其表达强度也无显 著性差异（ｐ＞０．０５）。ｐ５３与ｐ１６、ｐ１６与ｂｃｌ－２表达之间均无显著相关性（Ｐ＞０．０５）,而ｐ５３与ｂｃｌ－２表达之间存在显著相 关性（Ｐ＜０．０５）。结论：在胃癌发生发展过程中,抑癌基因（ｐ５３、ｐ１６）４抗凋亡基因（ｂｃｌ－２）之间存在既独立又协同的作 用。     

人胃癌p16/CDKN2基因蛋白质水平的异常表达

目的ｐ１６／ＣＤＫＮ２基因是新近发现的肿瘤抑制基因，已有研究表明该基因在许多肿瘤出现缺失、突变或重排．胃癌细胞系中有高频率纯合子缺失，应用Ｓｏｕｔｈｅｒｎｂｌｏｔ和ＳＳＣＰ技术在胃癌手术标本中未发现有该基因的缺失．本文首次研究胃癌中ｐ１６／ＣＤＫＮ２基因在蛋白水平的表达．方法应用蛋白Ａ金探针免疫组化技术对３０例胃癌和２０例正常胃粘膜标本的ｐ１６进行分析．结果所有正常对照组均有ｐ１６表达，其阳性细胞百分率为７２５５％±１７２２％；而胃癌中的阳性细胞百分率为５４９０％±２８９０％，明显低于正常对照（Ｐ＜００５）．在肿瘤病例中有２３３３％（７／３０）ｐ１６表达减低，１０％（３／３０）未表达ｐ１６．此外有１例呈过度表达．结论胃癌中有ｐ１６的异常表达，免疫组化技术可能较准确地反映ｐ１６的表达，更适合于临床研究．     

Structure of the Sec23p/24p and Sec13p/31p complexes of COPII

COPII-coated vesicles carry proteins from the endoplasmic reticulum to the Golgi complex. This vesicular transport can be reconstituted by using three cytosolic components containing five proteins: the small GTPase Sar1p, the Sec23p/24p complex, and the Sec13p/Sec31p complex. We have used a combination of biochemistry and electron microscopy to investigate the molecular organization and structure of Sec23p/24p and Sec13p/31p complexes. The three-dimensional reconstruction of Sec23p/24p reveals that it has a bone-shaped structure, (17 nm in length), composed of two similar globular domains, one corresponding to Sec23p and the other to Sec24p. Sec13p/31p is a heterotetramer composed of two copies of Sec13p and two copies of Sec31p. It has an elongated shape, is 28-30 nm in length, and contains five consecutive globular domains linked by relatively flexible joints. Putting together the architecture of these Sec complexes with the interactions between their subunits and the appearance of the coat in COPII-coated vesicles, we present a model for COPII coat organization.     

Immunohistochemical Expression of p16, p53, and p63 in Colorectal Adenomas and Adenocarcinomas

Purpose The aim of this study was to investigate the immunohistochemical expression of p16, p53, and p63 proteins according to some pathologic parameters related to colorectal adenomas and adenocarcinomas such as grade of dysplasia and histologic type. Methods Immunohistochemistry with the antibodies p16, p53, and p63 was performed in tubular, tubular-villous, and villous adenomas (n = 30) and in well, moderately, and poorly differentiated adenocarcinomas (n = 30). The p63-positive cases were submitted to double immunolabeling with the cytokeratin 5 (CK5). Results The p16 and p53 labelings were observed in some adenomas and adenocarcinomas but without any association with p63 expression, histologic type, or grade of differentiation of the neoplasm. P63 expression was found mainly in the villous adenomas and in the poorly differentiated adenocarcinomas. The poorly differentiated adenocarcinomas also exhibited coexpression of CK5 and p63. Conclusions Despite both p16 and p53 having been detected in colorectal neoplasms, they were not related to the different histologic variables nor to the expression of p63. However, p63 expression was closely associated with villous adenomas and poorly differentiated adenocarcinomas. Thus, p63 may represent a marker of poor differentiation in colorectal neoplasms. The coexpression of p63 and CK5 observed in this study could be related to divergent differentiation during the development of colorectal cancer, although further studies are warranted to refine the understanding of this process.     

Contribution of p53, p63, and p73 to the developmental diseases and cancer

Tumor suppressor TP53 gene is one of the most mutated genes in human genome. Inactivating somatic mutations and disruption of p53 protein have been described in almost all human malignancies. Its inactivation by germline mutation leads to the rare but severe familial precancerosis termed Li-Fraumeni syndrome. This syndrome is characterized by the early onset of different types of cancers including soft-tissue sarcomas, breast and brain cancers, leukemias, lung, laryngeal cancers, and adrenocortical carcinomas. The key role of p53 in tumor suppression has been confirmed in animal models as well. The p53 -knock-out and knock-in animals were born alive but were tumor prone. In the late nineties, two genes with high homology with TP53 were discovered, TP73 and TP63, respectively. Animal models showed that p73 is an important player in neurogenesis, sensory pathways and homeostatic control. The p63 is critical for the development of stratified epithelial tissues such as epidermis, breast, and prostate. Despite the structural similarities with p53, the function of these proteins in tumorigenesis is controversial. On one hand, there are evidences that both, p63 and p73-deficient animals are not tumor prone; on the other hand, there is evidence that such animals develop tumors later during their life. Unlike in TP53 gene, mutations in TP63 and TP73 genes are rare, however, germline mutations in TP63 are linked to the human developmental diseases. In this minireview, we describe the contribution of the p53, p63, and p73 to human pathology with emphasis on their different roles in development and tumorigenesis.     

Immunodominant epitopes of HIV-1 p17 and p24.

Immunodominant antibody-binding sites were mapped using overlapping synthetic peptides of the structural proteins p17 and p24 of human immunodeficiency virus type 1 (HIV-1). Using sera from HIV-1-infected individuals at a variety of disease states, three major epitopes were identified within p17 and one within p24. Antibodies which recognized these epitopes were present in all risk groups throughout all stages of HIV infection, regardless of the presence of high levels of serum p24 antigen.     

Chromosome 17p and p53 changes in lymphoma

The clinical course of lymphoma patients in whom rearrangements or deletions of the short arm of chromosome 17 (17p) were evident by cytogenetics was rapidly progressive with a short survival. The gene for the protein designated p53 resides in 17p. We studied four lymphoma cell lines derived from human tumours, and 25 tumour samples of patients with lymphomas, for any evidence of p53 genomic changes by Southern blot technique. The four cell lines and four of the 25 tumour samples showed numerical changes of chromosome 17 or structural abnormalities of 17p (translocations or deletions). Allelic loss of the p53 gene was found in two of the four cell lines, and one of these in addition showed a rearrangement of the 3' end of the gene. Of the four tumours known to have chromosome 17 abnormality, one specimen showed allelic loss of the p53 gene. None of the remaining tumour samples showed any significant change. These studies suggest that acquisition of changes in the short arm of chromosome 17, which may be interrelated with the p53 gene, may carry a poor prognosis in patients with non-Hodgkin's lymphoma.