肝细胞肝癌中VEGF、p53、mdm2蛋白表达及其相互关系

目的　研究肝细胞肝癌 (HCC) VEGF、p5 3、m dm2蛋白表达及其相互关系。方法　用免疫组化 S- P法或SAP法检测 HCC组织 VEGF、mdm2和 p5 3蛋白表达 ,计数微血管密度 (MVD) ,并与临床病理指标比较分析。结果　 72例 HCC中 VEGF、p5 3、mdm2蛋白阳性表达分别为 6 2 .5 %、4 1.6 %和 33.3% ;VEGF和 p5 3,VEGF和 m dm2 ,mdm2和 p5 3蛋白表达有相关性 (P<0 .0 5 )。 2 5例癌旁组织中 VEGF蛋白阳性表达为 2 0 .0 % ,m dm2蛋白阳性表达为 8.0 % ,p5 3蛋白阳性表达为 8.0 %。肝癌组织和癌旁组织 VEGF、m dm2和 p5 3蛋白表达差异有显著性 (P<0 .0 5 )。 10例正常肝组织无 VEGF、mdm2和 p5 3蛋白表达。 HCC组织中 VEGF、p5 3、mdm2蛋白阳性表达以及高MVD与血管侵犯和转移倾向明显相关 (P<0 .0 5 )。结论　 HCC组织中 VEGF、p5 3、mdm2蛋白过表达。p5 3突变和mdm2蛋白过表达 ,是 VEGF表达上调的原因之一 ,并与 HCC组织中血管侵犯和转移倾向有关     

mdm2、p14基因的扩增与胃癌的关系

背景与目的:肿瘤的发生与基因的变化密切相关,p53基因的变化被认为是肿瘤发生的一个重要原因,mdm2和p14被认为是调控p53功能的两个重要基因。目前,关于mdm2和p14在胃癌发病中作用的报道较少。本研究通过观察胃癌细胞中癌基因mdm2和抑癌基因p14的扩增水平,分析mdm2和p14与胃癌发生、发展的关系。方法:取10例正常胃粘膜(对照组)和45例胃癌组织(经病理检查证实为胃腺癌,其中高分化、中分化、低分化各15例),采用RT-PCR方法检测全部标本中p14和mdm2mRNA水平的变化。结果:(1)mdm2基因扩增阳性率在胃癌组织中为73.3%,与正常组织的40.0%比较,差异有显著性(P<0.05)。胃癌组织中高分化的93.3%、中分化的80.0%、低分化的46.6%,三组之间两两比较差异有显著性(P<0.05)。(2)p14基因扩增阳性率在胃癌组织中60.0%,与正常组织的50.0%比较差异无显著性(P>0.05),其中高分化的60.0%、中分化的66.6%、低分化的53.3%,三组之间两两比较差异无显著性(P>0.05)。结论:(1)mdm2基因扩增与胃癌的发生发展有密切的关系;(2)本研究未能证明p14与胃癌有关。     

mdm2-p53 Interaction: lack of correlation with the response to 5-fluorouracil in advanced colorectal cancer

OBJECTIVE: We investigated the relevance of mdm2 and p53 primary tumour expression to the clinical outcome of a consecutive series of advanced colorectal cancer patients treated with a 5-fluorouracil-based chemotherapy. METHODS: The expression of p53 and mdm2 was analyzed by an immunohistochemical assay in 80 formalin-fixed paraffin embedded primary tumour samples and related to the clinical response to 5-fluorouracil therapy and to the prognosis of the patients. In a subgroup of 46 tumours, the apoptotic index (AI) as determined by the Tunel technique was also assessed. RESULTS: Nuclear immunostaining of p53 and mdm2 was present in 42 and 30% of the cases, respectively. No correlation was demonstrated between p53 and mdm2 expression (rs = -0.01; p > 0.05). With regard to the clinical outcome, no statistical association was demonstrated among p53 and mdm2 expression, AI, probability of clinical response to treatment, time to progression, or overall survival. The subgroup of patients with a p53-negative/mdm2-positive tumour showed a worse response rate (15%); however, mdm2-positive/AI-negative tumours showed a 0% (0/7) probability of a clinical response as compared with 30% (9/30) of the remaining tumour patient subgroups; this also translated in a significantly worse overall survival probability (p = 0.01 by log rank). CONCLUSIONS: The analysis of mdm2 expression does not add significant clinical information in colorectal cancers with a different p53 status. Conversely, further analysis of AI seems to give data of a promising prognostic-predictive value.     

骨巨细胞瘤mdm2、p185、p21及p53免疫组化研究

[目的]探讨mdm2、p185、p21及p53在骨巨细胞瘤（GCT）的表达及与GCT病理分级和复发的关系。[方法]应用SP免疫组织化学方法检测mdm2、p185、p21及p53在52例GCT中的表达（GCT按Jaffe分级：Ⅰ级15例、Ⅱ级25例、Ⅲ级12例）。[结果]52例GCT中mdm2、p185、p21及p53的阳性表达率分别为34.6%（18/52）,21.2%(11/52),13.5%(7/52)及26.f9%(14/52)。不同病理分级阳性表达均无显著性差异。mdm2、p185、p21、p53在复发和无复发的病例中,阳性表达率分别为61.5%(8/13)、25.6%(10/39);38.5(5/13)、15.4%（6/39）;23.1%(3/13)、10.3%(4/29);46.2%(6/13)、20.5%(8/39)。GCT复发与否之间的mdm2表达有显著性差异（P=0.018),而p185、p21及p53的表达无显著性差异。[结论]mdm2、p185、p21及p53在GCT中的表达与病理分级差异无关,而mdm2的表达与其复发与否有关。     

mdm2、p53在胶质瘤中的表达意义及与临床病理特征的关系

目的:分析mdm2、p53在胶质瘤中的表达意义及与临床病理特征的关系。方法:选取我院2012年4月至2013年4月期间存档的54例胶质瘤石蜡标本以及相应瘤旁正常组织标本作为研究对象，将胶质瘤石蜡标本作为观察组，将瘤旁正常组织标本作为对照组。采用LSAB免疫组化法测量两组样本中mdm2、p53蛋白表达水平，分析上述蛋白在胶质瘤患者疾病发生及发展中的具体意义。结果:胶质瘤石蜡标本中mdm2、p53阳性表达率显著高于相应瘤周正常组织标本（P＜0.05）；Ⅲ、Ⅳ期胶质瘤患者p53、mdm2阳性表达率及“+++”表达率显著高于Ⅰ、Ⅱ期患者（P＜0.05）；p53、mdm2高表达患者术后生存时间均显著低于p53、mdm2低表达患者（P＜0.05）；p53、mdm2阳性表达率均与疾病分期以及淋巴结转移有明显相关性（P＜0.05）；mdm2、p53蛋白在胶质瘤中呈正相关（r=0.713，P＜0.05）。结论:mdm2通过调节p53蛋白的表达对胶质瘤发生发展起调控作用，Ⅲ、Ⅳ期疾病分期及淋巴结转移等因素均对mdm2、p53在肿瘤细胞中的异常表达有相关性，临床中可针对上述指标阳性表达程度预测患者病情发展，并为后续治疗方案的制定及改善提供相应的数据支持。     

Expression of p21/waf1 in oral squamous cell carcinomas--correlation with p53 and mdm2 and cellular proliferation index

The cyclin-dependent kinase inhibitor p21/waf1 is regulated by p53-dependent and p53-independent pathways. In addition, mdm2 is an oncogene which forms an auto-regulatory loop with the normal p53 protein and its role has been implicated in oncogenesis. To determine whether a correlation exists between the expression of these gene products, tumor differentiation, tumor staging and radiation therapy, we investigated the expression of p21, p53 and mdm2, and cellular proliferation by Ki-67 (MIB1) labeling index using immunohistochemistry in 88 human oral squamous cell carcinoma (SCC) samples from 56 patients. Tumor expression of all nuclear proteins was scored according to the percentage of positive cancer nuclei, both with the cancer tissue as a whole as well as in different epithelial compartments of differentiation. Positive p21, p53, mdm2 and MIB1 staining was present in 82.4, 67.8, 25.9 and 98.8% of the SCC samples. The staining in different epithelial compartments of differentiation varied: those of p21 and mdm2 present predominantly in suprabasal and upper regions of the tumors: those of p53 and MIB1 in basal and suprabasal regions. Higher levels of p21 expression were seen in actively proliferating tumors (P = 0.025). p21 expression positively correlated with mdm2 expression but not with p53 expression. Moreover, the level of p21 expression was higher in older patients (P = 0.024) and female patients (P = 0.008). There was no significant association among p53, mdm2 and MIB1. Expression of p53 was higher in tumors with poorer cellular differentiation and in younger patients (P = 0.038 and 0.028). There was no association between tumor stage by TNM classification and the expression of any of these gene products or proliferation index. Radiation therapy did not alter the expression of any of these. To conclude, p21 protein was overexpressed in oral SCCs, and this overexpression was related to cell proliferation index and mdm2 expression but independent of p53 protein alteration. Overexpression of p21 alone appeared to be insufficient to suppress tumor progression.     

乳腺癌组织MDM2和p53蛋白质的表达水平及其与病理指标的关系

研究乳腺癌组织ＭＤＭ２和ｐ５３蛋白质的定位、表达水平及其与肿瘤大小、病理分型、分类、分级、癌周浸润程度、纤维组织反应和淋巴细胞反应等临床病理指标的关系。方法应用单克隆抗体和链霉亲和素－生物素－过氧化物酶复合物（ＳＡＢＣ）免疫组织化学染色方法，检测１０６例乳腺癌组织石蜡切片标本ｍｄｍ２和ｐ５３蛋白质的定位和表达水平，比较其与各病理指标的关系。结果（１）乳腺癌组织ｍｄｍ２和ｐ５３蛋白质均明确定位于细胞核；（２）１０６例乳腺癌组织ｍｄｍ２表达阳性率为８１．１％，ｐ５３为７５．３％，ｍｄｍ２与ｐ５３蛋白质的表达水平呈正相关系；（３）乳腺癌组织ｍｄｍ２和ｐ５３蛋白质的表达水平与病理学分级、癌周浸润程度和纤维组织反应有关（Ｐ＜０．０５），而与肿瘤大小、病理分型、分类和淋巴细胞反应无关（Ｐ＞０．０５）。结论检测乳腺癌组织ｐ５３蛋白质和ｍｄｍ２的表达水平可作为判断细胞分级、分化和肿瘤生物学行为的指标之一。     

A novel exon within the mdm2 gene modulates translation initiation in vitro and disrupts the p53-binding domain of mdm2 protein

The mdm2 protein interacts with a number of proteins involved in cell growth control. Such interactions favour cell proliferation and may explain the oncogenic potential of mdm2 when over-expressed in cells. Interaction with the tumour suppressor p53 involves the N-terminus of mdm2 and targets p53 for rapid degradation by the ubiquitin pathway. We now describe a novel, highly conserved exon of mdm2 (exon alpha) which includes an in-frame UGA stop codon. Expression of exon alpha disrupts in vitro translation of the p53 binding domain of mdm2. We propose that exon alpha induces translation re-initiation at an internal AUG codon within the mdm2 alpha mRNA isoform. The putative mdm2 alpha protein lacks the N-terminus of mdm2 and shows little, if any, binding capacity for p53. Mdm2 alpha mRNA is expressed in a tissue-specific manner and is observed predominantly in testis and peripheral blood lymphocytes. We propose that mdm2 alpha expression may provide a mechanism for uncoupling mdm2-p53 interaction in certain cell types and/or under specific conditions of cell growth.     

食管鳞癌组织中p53与p27及mdm2蛋白的表达及其意义

目的:探讨癌基因蛋白p53、p27及mdm2在食管鳞癌组织中的表达及其意义。方法:采用免疫组织化学EnVision二步法对85例食管鳞癌及其癌旁组织进行p53、p27及mdm2蛋白表达的检测。结果:85例食管鳞癌组织中p53阳性表达率为70·6%(60/85),癌旁组织为75·0%(39/52);p27与mdm2蛋白在癌组织中的阳性率分别为72·9%(62/85)和83·5%(71/85),明显高于癌旁组织的34·6%(18/52)和53·8%(28/52),P<0·05;且从鳞状上皮非典型增生→原位癌→鳞癌的发展过程中,p27蛋白的阳性表达率逐渐上升。p27蛋白阳性表达与组织学分级呈正相关,r=0·234,P<0·05;而mdm2阳性表达与组织学分级呈负相关,r=-0·272,P<0·05;三者阳性表达率均与浸润深度及淋巴结转移无关,P>0·05;p53与p27和mdm2蛋白的表达无相关性,P>0·05。结论:检测p53、p27及mdm2蛋白在食管鳞癌的表达有助于了解食管癌的发生发展以及推断临床预后。     

Analysis of p53 mutational events and MDM2 amplification in canine soft-tissue sarcomas.

Canine cancer is of major significance in terms of animal health and welfare and soft tissue sarcomas are an important group of tumours accounting for approximately 15% of all canine tumours presented. Abnormal p53 protein expression and gene mutations have been identified in a number of different canine tumour types. However, mdm2 gene amplification has only been investigated in a limited number of canine osteosarcomas. In this present study a series of canine soft-tissue sarcomas (STS) were examined for p53 mutations and/or mdm2 amplification. For p53 mutational studies polymerase chain reaction and direct DNA sequencing was used. Gene mutations were identified in 6 of 30 (20%) primary tumour cases including MPNST (n=3) leiomysarcoma (n=1), heamangiosarcoma (n=1) and sarcoma (n=1). mdm2 gene amplification was assessed by Southern Blot. Although there was no evidence for major gene rearrangements, gene amplification was detected in 4 of 35 (11.4 %) primary tumours including MPNST (n=2), rhabdomyosarcoma (n=2). A total of 33 cases were examined for both p53 mutations and mdm2 amplification. Seven of the tumours were positive for p53 mutations, while five were positive for mdm2 amplification. With the exception of one case, a reciprocal relationship between the presence of a p53 mutation and mdm2 gene amplification was demonstrated.     

Expression and significance of p53 and mdm2 in atypical intestinal metaplasia and gastric carcinoma

Subtypes of intestinal metaplasia may have different manifestations in the carcinogenesis of gastric mucosa. The present study aimed to investigate expression of murine double minute gene 2 (mdm2) in atypical intestinal metaplasia (AIM) and its relationship to gastric carcinoma. Intestinal metaplasia (IM) specimens were obtained from 58 cases. Using a novel classification of IM, the specimens were classified according to morphological changes exhibited in the gastric mucosa; specifically, atypical intestinal metaplasia (AIM) and simple intestinal metaplasia (SIM). The gatric carcinoma specimens were then compared with types I, II and III IM based on different substances present in the mucous. Envision immunohistochemical technique was applied to the detection of the expression of p53 and mdm2 in 58 IM and 30 gastric carcinoma cases. Expression of both p53 and mdm2 proteins was found to be higher in gastric carcinomas (p53, 56.67%, 17/30 and mdm2, 53.33%, 16/30) and AIM (p53, 51.85%, 14/27 and mdm2, 51.85%, 14/27) as compared to SIM (p53, 25.81%, 8/31 and mdm2, 19.35%, 6/31) (P<0.05). A similar pattern of expression of mdm2 protein was found in type I (36.84%, 7/19), type II (38.46%, 10/26) and type III (23.08%, 3/13) IM and gastric carcinoma (53.33%, 16/30). p53 expression was higher in gastric carcinoma (56.67%) compared to type I IM (26.32%) (P<0.05). However, no differences were evident among type II (42.31%, 11/26), type III (46.15%, 6/13) IM and gastric carcinoma. AIM may reveal the precancerous nature of gastric carcinoma more clearly than SIM or the conventional IM subtypes. Additionally, AIM may be involved as a preneoplastic lesion and therefore be an effective indicator in the clinical follow-up of gastric carcinoma patients.     

鼻腔NK/T细胞淋巴瘤中p53相关蛋白和潜伏膜蛋白1的表达及其临床意义

目的 探讨鼠双微体2(mdm2)、p53、p21基因和潜伏膜蛋白1(LMP-1)在鼻腔NK/T细胞淋巴瘤(NKTL)中的表达及相互作用关系,以及其与NKTL临床分期和预后的关系.方法 收集62例NKTL患者的临床病理资料,并进行随访.取62例NKTL组织构建组织芯片,采用免疫组化SP法检测mdm2、pS3、p21及LMP-1蛋白的表达情况;应用原位杂交法检测EBER1/2的表达.结果 mdm2、p53、p21和LMP-1蛋白在NKTL中的阳性表达率分别为61.3%、79.0%、58.1%和48.4%,EBER1/2的阳性表达率为90.3%.随着肿瘤临床分期的进展,mdm2、p53和p21蛋白的阳性表达率逐渐升高,并与临床分期相关(均P<0.05).mdm2、p53和p21蛋白的表达呈正相关(P<0.05),其阴性表达组患者的预后均好于阳性表达组(均P<0.05).LMP-1蛋白的表达与临床分期和预后无关(P>0.05).p53蛋白的表达水平是NKTL的独立预后因素.结论 mdm2、p53、p21的蛋白表达与NKTL的发生和发展密切相关,可作为评估NKTL生物学行为的良好指标.p53蛋白的表达水平是NKTL的独立预后因素.     

In squamous cell carcinoma of the vulva, overexpression of p53 is a late event and neither p53 nor mdm2 expression is a useful marker to predict lymph node metastases.

To offer more tailored treatment to individual patients with squamous cell carcinoma of the vulva, more accurate prediction of lymph node metastases is required. As p53 and mdm2 are genes known to be involved in the development of other tumours, we studied expression of p53 and mdm2 in carcinogenesis of squamous cell carcinoma of the vulva and their clinical relevance. Archival material of 141 T1 and T2 vulvar tumours were used. Of the 141 primary tumours, the corresponding 39 lymph node metastases (LNM) were studied, and in 90 cases the pre-existent epithelia adjacent to the tumour (EAT) and in 14 cases vulvar intraepithelial neoplasia adjacent to the tumour (VIN) was also investigated. Detection of p53 and mdm2 protein was immunohistochemically performed. Scoring categories were: negative (1); weakly positive (2); moderately to markedly positive (3); and markedly positive (4). Overexpression of p53 was seen in 56% of the LNM, 39% of the primary tumours, 21% of the VIN lesions and 0% in the group of EAT. No relation was found between overexpression of p53 in the primary tumour and LNM. Expression of mdm2 was seen in 14% of the primary tumours, of which four cases were marked positive. In the group of LNM no mdm2-positive staining was observed. In the group of EAT, 25% was mdm2-positive, of which six cases were marked positive. In the group of VIN, 36% showed moderate (score 3) mdm2 expression. No relation was found between expression of mdm2 and LNM. In squamous cell carcinoma, overexpression of p53 is a late event in carcinogenesis. Marked expression of mdm2 is rarely seen in vulvar carcinomas, indicating that aberrant p53 cannot induce mdm2 expression. LNM cannot be predicted by detection of these proteins.     

EB病毒相关胃癌与mdm2，p53及p21基因异常的研究

 目的 探讨p53基因突变以及mdm2，p53和p21蛋白表达异常在EBV相关胃癌（EBVaGC）发生发展中的作用。方法 应用免疫组化技术检测13例EBVaGC、45例临床病理资料与之匹配的EBV阴性胃癌（EBVnGC）组织中 mdm2，p53和p21蛋白的表达；PCR-SSCP银染技术结合DNA序列分析检测p53基因exon 5~8突变；RT-PCR检测EBV相关基因的表达。结果 E-BVaGC组与EBVnGC组相比，两组间mdm2，p53和p21蛋白的阳性检出率差异无统计学意义（P = 0.830 0；P = 0.791 2；P = 0.353 1），但EBVaGC组p53蛋白过表达率（15.38 %）明显低于EBVnGC组（57.78 %），两组间差异有统计学意义（P = 0.008 5）。mdm2蛋白阳性表达与p53蛋白过表达呈显著正相关（P = 0.000 8，r = 0.439 1）；p21与p53蛋白共同表达率较高，但经计数资料相关性统计学分析表明两者无显著相关性（P = 0.2501，r = 0.202 5）。2例EBVnGC检测到p53基因突变，突变均位于exon 5，13例E-BVaGC和58例相应癌旁组织均未检测到p53基因突变。13例EBVaGC核抗原基因EBNA1均为阳性，潜伏膜蛋白基因LMP1均为阴性，即刻早期基因BZLF1，早期基因BARF1和BHRF1阳性率分别为46.15 %（6／13），46.15 %（6／13）和15.38 %（2／13），三者与EBVaGC组织中mdm2，p21和p53蛋白的表达均无显著相关性（P＞0.05）。 结论 EBV感染以及mdm2，p53和p21蛋白表达异常与胃癌发生有关； p53基因突变可能并非胃癌组织中p53蛋白异常累积的主要原因；胃癌组织中EBV感染与p53蛋白的异常表达有关，而与mdm2和p21蛋白的异常表达以及p53基因突变无显著相关性。     

MDM2/p53 co-expression in oral premalignant and malignant lesions: potential prognostic implications.

The expression of MDM2 protein in betel and tobacco related oral malignancies in Indian population, its relationship to clinicopathological parameters and p53 protein expression was investigated. Sixty five oral squamous cell carcinomas (SCCs), 33 premalignant lesions (leukoplakia) and 30 normal oral tissues were assessed by immunohistochemical analysis. MDM2 protein was overexpressed in 51/65 (78%) oral SCCs and 17/33 (52%) premalignant lesions; 11/23 hyperplastic lesions and 6/10 dysplastic lesions. mdm2 gene amplification is an infrequent event in oral tumorigenesis. Elevation in the level of MDM2 protein not only in oral SCCs but also in premalignant lesions suggests that altered MDM2 expression is an early even in the pathogenesis of oral neoplasia. The hallmark of the study was the significant association of MDM2 expression with the p53 protein accumulation in 16/33 (49%) oral premalignant lesions (p = 0.001) and 39/65 (60%) malignant lesions (p = 0.021), suggesting an active role for MDM2 in binding and inactivating p53 in oral tumorigenesis. Further, significant association of MDM2/p53 co-expression was observed with advanced tumour stage (p = 0.0009), as well as lymph node metastasis (p = 0.0325) features associated with aggressive tumour behaviour and poor prognosis. Discordant MDM2+/p53-phenotype was observed in 12/65 (18%) oral SCCs suggesting a p53-independent role for MDM2 in the pathogenesis of a subset of oral carcinomas. In conclusion, alterations in MDM2 and p53 expression are early events likely to be involved in preinvasive stages in oral tumorigenesis and may be indicative of a 'gain of function' phenotype with more aggressive characteristics.     

Nucleostemin mRNA is expressed in both normal and malignant renal tissues

Nucleostemin (NS), a p53-binding protein, has been shown essential for stem and cancer cell proliferation and implicated in oncogenesis. To explore potential contributions of NS to the development of clear cell renal cell carcinomas (ccRCCs), we determined NS expression in ccRCC cell lines, and in paired normal and malignant renal tissues from 31 patients with ccRCC. Nucleostemin mRNA and/or protein expression was observed in all four cell lines and 27 of 31 (87%) tumour specimens. Surprisingly, 16 of 31 (52%) adjacent normal renal samples also expressed NS mRNA and its levels in four of them were comparable with those in paired tumour tissues. Three of the patients had detectable NS mRNA in their normal renal tissues whereas lacked its expression in the matched tumours. Compared to the oncogene c-MYC expression in these same samples, NS expression showed a much less specificity for ccRCC. We further demonstrated that NS mRNA expression was closely associated with cellular proliferation in normal fibroblasts or T lymphocytes and renal cell carcinoma cell lines. Collectively, NS expression widely occurs in normal and malignant renal tissues, and is likely a proliferation marker rather than a unique regulator of cell proliferation and survival in stem and cancer cells.     

mdm2和p53基因在急性白血病细胞中的表达及意义

目的：探讨人急性髓细胞性白血病（ａｃｕｔｅ ｍｙｅｌｏｉｄ ｌｅｕｋｅｍｉａ．ＡＭＬ）细胞ｍｄｍ２及ｐ５３基因蛋白表达水平,相互关系及与临床预后的关系。方法：用免疫组化方法测定ｍｄｍ２及ｐ５３蛋白表达,ＨＰＩＡＳ－１０００高清晰度病理图像细胞测定系统分析结果。结果：７５％的ＡＭＬ患者表达不同程度的ｍｄｍ２蛋白,且在各种分型中均有ｍｄｍ２蛋白过度表达者：１８．７５％的ＡＭＬ患者表达ｐ５３蛋白;在ＡＭ