肿瘤抑制基因p53及p16与胃癌生物学行为的关系

目的探讨肿瘤抑制基因ｐ５３和ｐ１６异常与胃癌生物学行为的关系．方法采用免疫组化ＡＢＣ法检测５８例原发性胃癌（男３８例，女２０例，年龄３７岁～７６岁），Ｐ５３和Ｐ１６蛋白的表达变化．所有组织均新鲜取材，并迅速用８５０ｍｌ／Ｌ酒精固定，石蜡包埋，连续切片．结果受检组织中ｐ５３和ｐ１６阳性表达率分别为５１７％（３０／５８）和４８３％（２８／５８）．Ｐ５３蛋白在低分化胃癌（７００％）、进展期胃癌（５６９％）、淋巴结阳性胃癌（７４１％）中的表达率高于相应的高分化、早期、淋巴结阴性胃癌的表达率（２７３％，１４３％，３２３％）（Ｐ＜００５），且ｐ５３高表达多见于弥散型胃癌（同肠型胃癌比）、累及浆膜的胃癌也较局限于粘膜层的胃癌有更高的Ｐ５３蛋白表达（Ｐ＜００５）；Ｐ１６蛋白表达与胃癌大多数生物学行为无明显关系，但其在淋巴结阳性胃癌中的表达率（３３３％），低于淋巴结阴性胃癌中的表达率（６１３％）；相关性分析显示；ｐ５３阳性组织大多伴有Ｐ１６蛋白阳性表达（Ｐ＜００５）．结论Ｐ５３蛋白异常表达对胃癌生物学行为有广泛影响，Ｐ１６蛋白表达缺失可能是胃癌淋巴结转移的重要促发因素．     

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     

幽门螺杆菌阳性胃粘膜病变AgNOR和rasp21的表达

目的研究幽门螺杆菌阳性（Ｈｐ＋）不同胃粘膜病变的ＡｇＮＯＲ数量及ｒａｓｐ２１阳性表达率，探讨其生物学行为及Ｈｐ在此过程中可能的作用．方法经内窥镜病理检查证实胃粘膜病变（慢性浅表性胃炎、慢性萎缩性胃炎、肠上皮化生、异型增生、胃癌）共计２７８例．通过Ｈｐ检测（ＣＬＯｔｅｓｔ结合ＷａｒｔｈｉｎＳｔａｒｙ染色）证实其中１４６例阳性，１３２例阴性．分别对其粘膜标本作了ＡｇＮＯＲ定量及ｒａｓｐ２１表达的研究，比较不同胃粘膜病变中Ｈｐ阳性和阴性组间ＡｇＮＯＲ数目和ｒａｓｐ２１阳性表达率．结果除慢性浅表性胃炎外各病变中Ｈｐ＋组的ＡｇＮＯＲ数量均显著高于Ｈｐ－组（Ｐ＜００５或Ｐ＜００１）；除慢性浅表性胃炎及慢性萎缩性胃炎外各病变中Ｈｐ＋组的ｒａｓｐ２１阳性表达率均显著高于Ｈｐ－组（Ｐ＜００５）．结论Ｈｐ＋胃粘膜病变具有更多的肿瘤生物学行为，该菌可能刺激胃上皮细胞的过度增殖而启动恶性变．     

p53、p21^WAF1蛋白在非小细胞肺癌中的表达及其临床意义

目的 检测原发性非小细胞肺癌中ｐ５３、ｐ２１＾ＷＡＦ１蛋白表达与临床病理及预后的相关性。方法 应用免疫组织化学（ＳＰ法）方法。结果 共检测非小细胞肺癌１４７例,其中鳞癌６３例,腺癌６６例,腺鳞癌１４例,大细胞癌４例。ｐ５３蛋白总阳性率为６１．２％（９０／１４７）,鳞癌阳性率为６３．５％（４０／６３）,腺癌为５７．６％（３８／６６）,腺鳞癌为７１．４％（１０／１４）,大细胞癌２例阳性。ｐ２１＾ＷＡＦ１蛋白总阳性率为４０．１％（５９／１４７）,鳞癌为４１．３％（２６／６３）,腺癌为４２．４％（２８／６６）,腺鳞癌２８．６％（４／１４）,大细胞癌１例阳性。肺腺癌ｐ５３蛋白阳性表达与其预后相关,６６例腺癌中,生存率低于３年组和高于３年组的ｐ５３蛋白阳性率分别为７５％（２１／２８）和４４．７％（１７／３８）,差异显著（Ｐ     

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     

p53蛋白在胆囊腺癌中的表达及意义

应用免疫组织化学Ｓ．Ｐ法检测了４２例胆中腺癌和８例胆囊腺瘤中Ｐ５３蛋白的表达情况。结果显示，胆囊腺癌中Ｐ５３阳性率为４７．６％，胆囊腺瘤及癌旁正常粘膜阳性率均为０％，与胆囊腺癌比较，差异有显著性。     

有内分泌分化的直肠癌p53蛋白的表达

研究直肠癌内分泌分化与ｐ５３蛋白表达的关系及意义。采用免疫组织化学ＡＢＣ法检测４４例活检直肠癌组织嗜铬蛋白Ａ（ＣＧＡ）及Ｐ５３蛋白的表达，并分析它们与肿瘤分化程度之间的关系。结果显示Ｐ５３、ＣＧＡ阳性表达率分别为６８．２％（３０／４４）和３８．６％（１７／４４）；ＣＧＡ阳性及阴性病例Ｐ５３表达率分别为８８．２％（１５／１７）和５５．６％（１５／２７），两组比较Ｐ＜０．０２５（χ２检验）；Ｐ５３、ＣＧＡ在分化差的直肠癌中的表达呈增高趋势，但差异无显著性。Ｐ５３肿瘤抑制基因的变化在直肠癌的内分泌分化过程中可能发挥重要作用。     

胃癌组织p170基因表达的研究

为研究糖蛋白ｐ１７０基因在胃癌中的表达，对８０例内镜活检及术后确诊的胃癌组织用抗生物素－过氧化酶复合物进行免疫组化染色研究。结果，胃癌组织中ｐ１７０基因表达均增强，其阳性率达６６％及７１％，并且阳性表达与胃癌组织学类型及分化程度有一定关系，管状腺癌中ｐ１７０阳性表达率高，高、中分化腺癌高于低分化、粘液腺癌、乳头状腺癌等。其分布形式基本相似，主要位于细胞浆内，其次在细胞膜内，细胞核内偶见，癌旁组织也有较强阳性表达。在转移淋巴结组中阳性表达显著高于非转移淋巴结组，提示ｐ１７０与胃癌转移密切相关。结果显示糖蛋白Ｐ１７０在胃癌组织中的表达有可能成为一种新的肿瘤标志物。     

原发性肝癌转移与ras p53基因及其蛋白表达的关系

目的了解ｒａｓ，ｐ５３基因及其蛋白表达与原发性肝细胞癌（ＨＣＣ）转移的关系．方法应用免疫组化、狭缝杂交分别对１４例ＨＣＣ有转移者和１６例无转移者癌组织中ｒａｓ，ｐ５３基因蛋白和ＲＮＡ表达进行了研究．结果经微波修复抗原后，在１４例有转移ＨＣＣ组织中，Ｐ２１和Ｐ５３蛋白的阳性例数分别为１１例和１２例，在１６例无转移ＨＣＣ组织中，其阳性例数分别为５例和７例，两组间具有极显著性差异（Ｐ值分别为００１４和００２６）．ＨＣＣ有转移组ＮｒａｓＲＮＡ为无转移组的３～５倍，而两组间Ｐ５３ＲＮＡ量则几乎相等．结论经微波修复抗原后，Ｐ２１和Ｐ５３蛋白的免疫组化染色可作为衡量ＨＣＣ转移潜能的指标．     

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.     

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.     

Vta1p and Vps46p regulate the membrane association and ATPase activity of Vps4p at the yeast multivesicular body

Previous two-hybrid analysis of the 17 soluble class E Vps yeast proteins revealed that Vps46p/Did2p interacts with Vta1p and the AAA (ATPase associated with a variety of cellular activities) ATPase Vps4p. Here we report that the binding of Vps46p to Vps4p and Vta1p is direct and not mediated by additional proteins, and the binding of Vps46p to Vps4p is ATP independent. Vps46p regulates the membrane association of Vps4p and is required for the interaction of Vta1p with Vps32p/Snf7p of the ESCRT-III complex. Vta1p is a potent activator of Vps4p, stimulating the ATPase activity by 6- to 8-fold. These results reveal functional roles for the Vps46p and Vta1p proteins in regulating the ESCRT complex assembly/disassembly cycle in protein sorting at the yeast late endosome.     

初诊和复发急性髓性白血病p15、p16基因甲基化研究

目的探讨急性髓性白血病(AL)p15、p16、p18、p19基因失活的发生率及与疾病发生、发展、预后的关系。方法用聚合酶链反应(PCR)方法扩增46例患者的p15、p16、p18、p19基因外显子1和外显子2。再用限制性内切酶一PCR方法检测基因甲基化。结果46例患者中。急性淋巴细胞白血病(ALL)19例．11例p15基因失活,10例p16基因失活;急性非淋巴细胞白血病(ANLL)27例．9例p15基因失活,18例P16基因失活;均以甲基化失活为主。所有病例均无p18、p19基因失活。结论在AL发生、发展过程中。p15、p16基因失活主要是由于P15、p16基因甲基化所致。     

Analysis of the biologic properties of p230 Bcr-Abl reveals unique and overlapping properties with the oncogenic p185 and p210 Bcr-Abl tyrosine kinases

The reciprocal translocation between chromosomes 9 and 22 that fuses coding sequences of the Bcr and Abl genes is responsible for a remarkably diverse group of hematologic malignancies. A newly described 230-kd form of Bcr-Abl has been associated with an indolent myeloproliferative syndrome referred to as chronic neutrophilic leukemia. We have cloned the corresponding gene and examined the biologic and biochemical properties of p230 Bcr-Abl after retroviral-mediated gene transfer into hematopoietic cell lines and primary bone marrow cells. p230 Bcr-Abl-expressing 32D myeloid cells were fully growth factor-independent and activated similar signal transduction pathways as the well-characterized p210 and p185 forms of Bcr-Abl. In contrast, primary mouse bone marrow cells expressing p230 required exogenous hematopoietic growth factors for optimal growth, whereas p185- and p210-expressing cells were independent of growth factors. The 3 Bcr-Abl proteins exerted different effects on differentiation of bone marrow cells. p185 induced outgrowth of lymphoid precursors capable of tumor formation in immunodeficient mice. In contrast, p210- and p230-expressing bone marrow cells caused limited outgrowth of lymphoid precursors that failed to form tumors in immunodeficient mice. Removal of cytokines and autologous stroma from Bcr-Abl-expressing bone marrow cultures produced the expansion of distinct lineages by the various Bcr-Abl proteins. p185 drove expansion of cytokine-independent lymphoid progenitors, while p210 and p230 generated cytokine-independent monocyte/myeloid cells. These findings suggest that the different Bcr-Abl fusion proteins drive the expansion of different hematopoietic populations, which may explain the association of the various Bcr-Abl oncoproteins with different spectra of human leukemias. (Blood. 2000;95:2913-2921)     

Characterization of the TPR-MET oncogene p65 and the MET protooncogene p140 protein-tyrosine kinases.

The proteins encoded by the human TPR-MET oncogene (p 65tpr-met) and the human MET protooncogene (p140met) have been identified. The p65tpr-met and p140met, as well as a truncated TPR-MET product expressed in Escherichia coli, p50met, are autophosphorylated in vitro on tyrosine residues. Using the immunocomplex kinase assay, p140met activity was detected in various human tumor epithelial cell lines. In vivo, p65tpr-met is phosphorylated on both serine and tyrosine residues, while p140met is phosphorylated on serine and threonine. p140met is labeled by cell-surface iodination procedures, suggesting that it is a receptor-like transmembrane protein-tyrosine kinase.     

Structural integrity of the cyclin-dependent kinase inhibitor genes, p15, p16 and p18 in myeloid leukaemias

Summary The cyclin-dependent kinase inhibitors known as p15, p16 and p18 have been suggested as candidates for tumour suppressor genes. We examined these genes for their alterations in 46 myeloid leukaemias and 15 myeloid leukaemia cell lines, p16 mRNA expression was studied in 41 myeloid leukaemias. The p15 and p16 genes were either deleted or mutated in myeloid leukaemia lines at a high frequency [6/15 (40%) for p15; 8/15 (53%) for p16] but alterations in primary myeloid leukaemias are much less frequent [2/46 (4%) for p15; 3/46 (6%) for p16]. Alterations of p18 were not found in any of the samples. 13 primary myeloid leukaemia samples had negligible levels of p16 mRNA. In summary, the deletions of p15 and p16 genes identified in the myeloid leukaemia cell lines probably occurred during their in vitro immortalization. Alterations of the pl6 or pl5 gene only occurred in primary acute myeloid leukaemia samples that were of mixed myeloid/ lymphoid lineage (CD19/CD20-positive acute myeloid leukaemia [AML], CD2/CD19-positive AML, and lymphoid blastic crisis of chronic myeloid leukaemia). Further studies are required to determine if the absence of mRNA expression results from inactivation of the p16 gene.     

p16、p53、p21基因对肺癌细胞增殖的影响

目的 观察肿瘤抑制基因ｐ１６,ｐ５３及细胞周期信赖激酶抑制物ｐ２１基因单独或联合应用时对肺癌细胞增殖的影响。方法 应用十八酰基胺阳离子脂质体介导ｐ１６,ｐ５３,ｐ２１基因单独或共转染到非小细胞肺癌细胞系Ａ５４９和小细胞肺癌细胞系ＳＨ７７,观察转染后１,３,５日该细胞增殖的活力。采用四甲基偶氮唑 盐微量酶反应比色法（ＭＴＴ法）测定吸光度（Ａ）,以检测细胞增殖活力,结果 Ａ５４９细胞系：Ａ均值分别为：     

Loss of heterozygosity of chromosome 8p and 11p in the dysplastic nodule and hepatocellular carcinoma

BACKGROUND AND AIM: In hepatocarcinogenesis, both de novo and multistep pathways have been suggested, and in the latter a dysplastic nodule is the proposed precancerous lesion. But genetic changes involved in the dysplastic nodule are not well understood. In this study, we tried to determine whether allelic loss of the chromosome 8p and/or 11p could be involved in the development of the dysplastic nodule and/or hepatocellular carcinoma. Platelet-derived growth factor-receptor beta-like tumor suppressor gene (PRLTS) and deletion in liver cancer-1 tumor suppressor gene are located at 8p21.3-p22. The hepatitis B virus integration site and WT1 tumor suppressor gene are located at 11p13. METHODS: We therefore studied loss of heterozygosity (LOH) of chromosome 8p21.3-p22 and 11p13 in 22 dysplastic nodules and 21 hepatocellular carcinomas. The samples, microdissected from paraffin-embedded tissues, were examined using a polymerase chain reaction-based LOH assay using microsatellite markers. RESULTS: Loss of heterozygosity was detected for chromosome 8p21.3-p22 in nine (40.9%) of 22 dysplastic nodules and in eight (42.1%) of 19 hepatocellular carcinomas. D8S261, located adjacent to PRLTS, showed most frequent LOH: 28.6% in dysplastic nodule and 40.0% in hepatocellular carcinoma. Loss of heterozygosity on chromosome 11p13 was found in three (15.8%) of 19 dysplastic nodules and in six (31.6%) of 19 hepatocellular carcinomas. Loss of heterozygosity of D11S995 and D11S907 was found in 33.3% and 7.1% of dysplastic nodules, and 8.3% and 44.4% of hepatocellular carcinomas, respectively. CONCLUSION: These results suggest that at least one putative tumor suppressor gene involved in the development and progression of hepatocellular carcinoma may be located on 8p21.3-p22 and 11p13. Particularly, PRLTS might be related to an early genetic event of hepatocarcinogenesis.     

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.