Negative p53/Positive p21 Immunostaining Is a Predictor of Favorable Response to Chemotherapy in Patients with Locally Advanced Bladder Cancer

The relationship between clinical response to DNA-damaging drugs and p53 and p21 status in patients with locally advanced transitional cell carcinoma (TCC) of the bladder was assessed. The response to intraarterial chemotherapy (IAC) comprising 100 mg/m² of cisplatin (CDDP) and 40 mg/m² of pirarubicin (THP) and the prognosis were assessed in 23 patients (the mean follow-up period was 19 months). The p 53 gene status of tumors was analyzed at exons 5–8 using polymerase chain reaction-single strand conformation polymorphism analysis in 19 patients, and paraffinembedded tumor sections were immunostained for p⁵³ and p²¹ in 23 patients. The overall objective response rate (incidence of good responders) was 70%. The negative p53 group ( n =17) showed a significantly higher objective response rate than the positive p53 group ( n =6) (82% vs. 33%; P =0.045). The p 53 gene status or p21 staining status was not significantly associated with responsiveness. When the p53 and p21 immunostaining results were combined, good responders were more accurately predicted than by p53 staining status alone; the negative p53/positive p21 group ( n =12) showed an objective response rate of 92%, which was significantly higher than that of the positive p53 and/or negative p21 group (45%, n =11) ( P =0.027). Cause-specific survival of the negative p53 group was significantly superior to that of the positive p53 group ( P =0.015). Negative p53/positive p21 immunostaining is a possible predictor of favorable chemotherapeutic response in patients with TCC of the bladder.     

p53 alterations in recurrent squamous cell cancer of the head and neck refractory to radiotherapy

The aim of the study was to determine the incidence of p53 alterations by mutation, deletion or inactivation by mdm2 or human papillomavirus (HPV) infection in recurrent squamous cell cancer of the head and neck (SCCHN) refractory to radiotherapy. Twenty-two tumours were studied. The p53 status of each tumour was analysed by sequencing of exons 4-9 and by immunohistochemistry. Mdm2 expression was assessed by immunohistochemistry and HPV infection was assessed by polymerase chain reaction of tumour DNA for HPV 16, 18 and 33. Fifteen (68%) of the 22 tumours studied had p53 mutations, while seven had wild-type p53 sequence. p53 immunohistochemistry correlated with the type of mutation. HPV DNA was detected in 8 (36%) tumours and all were of serotype HPV 16. Of these, five were in tumours with mutant p53 and three were in tumours with wild-type p53. Mdm2 overexpression was detected in 11 (50%) tumours. Of these, seven were in tumours with mutant p53 and four were in tumours with wild-type p53. Overall, 21 of the 22 tumours had p53 alterations either by mutation, deletion or inactivation by mdm2 or HPV. In this study, the overall incidence of p53 inactivation in recurrent head and neck cancer was very high at 95%. The main mechanism of inactivation was gene mutation or deletion which occurred in 15 of the 22 tumours studied. In addition, six of the seven tumours with wild-type p53 sequence had either HPV 16 DNA, overexpression of mdm2 or both which suggested that these tumours had p53 inactivation by these mechanisms. This high incidence of p53 dysfunction is one factor which could account for the poor response of these tumours to radiotherapy and chemotherapy. Therefore, new therapies for recurrent SCCHN which either act in a p53 independent pathway, or which restore p53 function may be beneficial in this disease.     

p53 Status in Multiple Human Urothelial Cancers: Assessment for Clonality by the Yeast p53 Functional Assay in Combination with p53 Immunohistochemistry

Multifocal synchronous or metachronous tumor development is a common observation in human urothelial cancer cases. However, the underlying mechanism has remained obscure. We have employed a new tool to investigate the p53 gene status, the yeast p53 functional assay, in combination with immunohistochemistry in a total of 50 tumor samples from 32 cases with urothelial cancers, including 8 with multiple synchronous tumor development and 2 demonstrating metachronous tumors. p53 mutations were found in 13 cases (9 with missense mutations, 3 with deletion, 1 with splicing mutation) by the yeast p53 functional assay. p53 protein overexpression was seen in all 9 cases with missense mutations, but in only one of the 4 cases with nonsense mutations. Two tumors without p53 mutation also showed positive p53 immunoreactivity. Overall, p53 abnormalities including mutations and/or protein overexpression were found in 15 (47%) cases. p53 abnormalities were significantly more frequent in non-papillary and in high grade tumors. Loss of the wild type allele in addition to a p53 mutation was suggested in 8 of the 15 (53%) cases. All 4 cases with mutations in multiple synchronous tumors had identical p53 mutations in the separate urothelial cancers, strongly suggestive of monoclonality. The one case with multiple metachronous tumors, in contrast, was characterized by variation in the p53 status, indicative of different clonal origins. In conclusion, combined assessment for p53 status as used here (yeast p53 functional assay plus immunohistochemistry) may provide insights into the molecular mechanisms of urothelial carcinogenesis.     

Overexpression of MDM2 in MCF-7 Promotes Both Growth Advantage and p53 Accumulation in Response to Estradiol

The overexpression of the oncogene product MDM2 is often observed in human breast cancer cells, especially in estrogen receptor (ER)-positive ones. To study the role of MDM2 protein in ER-positive breast cancer, we have established cell lines derived from MCF-7 which stably express increased and decreased levels of MDM2 by transfection of a mammalian expression vector containing human mdm2 cDNA in sense and antisense orientations, respectively. Interestingly, MDM2 overexpression in MCF-7 cells afforded a remarkable growth advantage under estradiol (E2)-sup-plemented condition. Then, we analyzed the expression of p53, which is an important regulator of growth and the cell cycle. Unexpectedly, the p53 accumulation induced by E2 was remarkably higher in MCF-7 cells stably overexpressing MDM2 than in the parent MCF-7 cells. On the other hand, reduction of MDM2 suppressed the E2-induced increase in p53 protein. Moreover, mdm2 antisense oligonucleotides prevented E₂-induced accumulation of p53. In the steady state, the cellular levels of p53 were also correlated with those of MDM2. These interactions are not consistent with the well-known role of MDM2, which acts as a negative regulator for p53 by inhibiting its function and promoting its rapid degradation. These results suggest that MDM2 may regulate the expression of p53 in the steady state and in response to E2 in breast cancer cells, and imply a novel and important role of MDM2 during breast carcinogenesis.     

尿路上皮肿瘤rasp21和p53蛋白和DNA含量的流式细胞定量研究

研究ｒａｓｐ２１和Ｐ５３表达和ＤＮＡ倍体异常与尿路上皮肿瘤发生关系。方法应用流式细胞术和细胞免疫荧光技术对５２例尿路上皮肿瘤ｒａｓＰ２１和Ｐ５３蛋白和ＤＮＡ含量进行定量检测。结论：ＤＮＡ倍体异常、ｒａｓＰ２１和Ｐ５３的共同表达参与尿路上皮肿瘤的发生和发展。     

Immunocytochemical Detection of p53 in Cultures of Exfoliated Cells from Urine of Patients with Urothelial Cancers

Early diagnosis of urothelial cancer is critical for successful treatment. Mutation of the p53 gene together with allelic loss of chromosome 17p correlates well with high grade and invasiveness of urothelial cancer. Moreover, this mutation is reported to be an early event for carcinoma in situ of the urothelium. In order to develop a new non-invasive diagnostic method for urothelial cancer, we have established a short-term culture system for urinary exfoliated cells from patients with urothelial cancer. Immunocytochemical detection of p53 in these urine-derived cells was conducted. Short-term cultures of exfoliated cells from 50 ml samples of urine from 52 patients with urothelial cancers were made. Adequate cell growth (>10⁵ cells per flask) was followed by passage onto glass chamber slides for p53 immunocytochemical staining. Successful passage was obtained in 40 of the 52 (76.9%) patients with urothelial cancers studied. The success rate for patients with tumors immunohistochemically positive for p53 nuclear accumulation was 90.5%, and 61.3% for those with tumors negative for p53 ( P <0.05). Results of immunochemical analyses of the p53 in the urine cells and those in the tumor samples were identical in 92.1% of the patients. Culture of exfoliated cells from urine would be a good, non-invasive method for the molecular diagnosis of urothelial cancer that should prove useful for the early detection and follow-up of tumors with p53 mutation.     

乳腺癌中的p53基因mRNA高表达的研究

应用反转录-半定量PCR技术检测47例乳腺癌组织中p53基因mRNA表达，并与临床预后因素进行统计学分析。结果发现：在乳腺正常腺体中有稳定的p53mRNA中度表达，而在乳腺癌组织中，p53mRNA呈高表达者为40．4％（19／47），且以在ER阴性的乳腺癌中增高明显（P＜0．05）。本文提示：p53基因在人类乳腺癌形成和肿瘤演进过程中起重要的作用，p53mRNA高表达的病人浸润性强、预后差。反转录一半定量PCR技术具有快速、简单、敏感可适于临床大规模应用之优点。     

Nonresponse to Neoadjuvant Chemotherapy for Muscle-Invasive Urothelial Cell Carcinoma of the Bladder

BackgroundCisplatin-based neoadjuvant chemotherapy (NC) is commonly used in the treatment of muscle-invasive urothelial cell carcinoma of the bladder (UC) and has been shown to improve survival. However, not all patients respond to NC, thus delaying the interval to potentially curative surgical therapy, risking disease progression and subjecting patients to potential morbidity from NC. In this study, we perform a retrospective analysis of patients who received NC prior to cystectomy to identify factors associated with nonresponse.Patients and MethodsWe identified 80 patients with clinical T2 to T4, N0 to N1 UC of the bladder who received NC and underwent radical cystectomy. Nonresponse was defined as patients with higher pathologic T stage than clinical stage or patients with nodal involvement identified on final pathology.ResultsOverall, 20% of patients were considered nonresponders. In multivariate analysis, age was predictive of nonresponse (P_trend < .05). Compared with those < 60 years of age, those aged 60 to 69 years (odds ratio [OR], 2.9; 95% CI, 0.7-12) and those aged ≥ 70 (OR, 5.0; 95% CI, 0.9-28) had higher odds of nonresponse. Patients who received gemcitabine-carboplatin had higher odds of nonresponse compared with those who received gemcitabine-cisplatin (OR, 4.4; 95% CI, 0.8-21).ConclusionA subset of patients receiving NC prior to cystectomy will experience disease progression. Future study will need to better identify methods to distinguish individuals more likely to benefit from NC and those that should receive upfront cystectomy.     

鼻咽癌p53蛋白表达与p53基因结构改变及mdm2蛋白表达的关系和意义

探讨影响ＮＰＣｐ５３蛋白表达的因素,Ｐ５３和ｍｄｍ２蛋白在ＮＰＣ发生中的变化和意义。方法采用免疫组化法检测ｐ５３和ｍｄｍ２蛋白、Ｓｏｕｈｅｒｎ杂交法检测Ｐ５３基因结构。     

ARF-mdm2-p53的相互作用途径

细胞周期素依赖性激酶4（cyclin-dependent kinase4,CDK4)抑制蛋白基因p16INK4α及其可变读框基因（alterative reading frame,ARF)-INK4α-ARF基因位于人染色体9p21的CDKN2A位点,该位点编码两个重叠的基因;p16INK4α和ARF基因,这两个基因的阅读框架不同,因此,p16和ARF基因的氨基酸顺序是完全不同的,ARF主要通过mdm2参与mdm2-p53通路的调节。目前研究表明ARF基因在肿瘤发生过程中可有起一定的作用,ARF基因功能的失活可能主要通过该基因启动子高度甲基化。本文就ARF与mdm2及p53相互作用途径做一综述。     

p14ARF在宫颈癌中的表达及其与p53表达相关性的研究

目的探讨宫颈癌组织p14ARF蛋白的表达及其与p53表达的相关性.方法应用免疫组化方法检测p14ARF、p53基因在41例宫颈癌及20例正常宫颈组织中的表达.结果p14ARF在正常宫颈组织中不表达,41例宫颈癌中35例表达阳性,占85.4%.病理分级为G1、G2级的宫颈癌的p4ARF阳性表达率为68.4%,G3级为100%,两者比较,有显著性差异(P＜0.05).宫颈癌组织中p53蛋白表达阳、阴性者中p14ARF蛋白表达阳性率分别为75.0%(12/16)和92.0%(23/25),两者比较,无显著性差异,p14ARF与p53表达不相关.结论p14ARF在宫颈癌中高表达有一定的诊断和估测预后价值,可能是宫颈癌新的肿瘤标志物.     

Infrequent Overexpression of p53 Protein in Epstein-Barr Virus-associated Gastric Carcinomas

Epstein-Barr virus (EBV) infection was studied in a total of 412 patients with poorly differentiated gastric adenocarcinoma by in situ hybridization for EBV-encoded small RNA. EBV-speciflc RNA was detected in tumor cell nuclei of 83 (20.1%) of 412 gastric carcinomas, of which 60 were histologically subclassified as gastric carcinoma with lymphoid stroma (GCLS). All EBV-positive gastric carcinomas as well as 90 randomly selected EBV-negative gastric carcinomas were further studied for p53 protein expression by immunohistocbemistry. The Overexpression of p53 protein was demonstrated in only 7 (8.4%) of 83 EBV-positive gastric carcinomas. This was in marked contrast to the frequency of 34.4% in EBV-negative gastric carcinomas. In addition, a few p53-positive nuclei were characteristically scattered in the tumors of many EBV-positive GCLS, but this was not regarded as p53 Overexpression arising from mutation of the gene. Our findings suggested that EBV-associated gastric carcinomas may arise through a different mechanism from other types of gastric carcinomas without EBV infection.     

血清 p53抗体与食管癌化疗敏感性的关系

背景与目的:近年许多资料报道 p53蛋白过表达与肿瘤耐药性的产生密切相关,可以作为预测肿瘤对化疗敏感性的指标.最近发现 p53蛋白过表达肿瘤患者血清中存在特异性的 p53抗体,且血清 p53抗体与 p53蛋白的过表达有着密切的关系,因而从理论上推测血清 p53抗体也可以作为预测肿瘤对化疗敏感性的指标.本研究通过体外药敏实验研究食管癌术后患者的肿瘤样本化疗敏感性和术前血清 p53抗体表达的关系.方法:采用 ELISA法检测 38例食管癌患者及 20例健康人血清 p53抗体的表达;采用 MTT比色法进行体外药物敏感实验,检测 38例食管癌患 者新鲜肿瘤组织标本对顺铂( DDP)、 5-氟尿嘧啶( 5-FU)、阿霉素( ADM)的敏感性.结果: 38例食管癌患者中血清 p53抗体阳性率为 47.3%( 18/38),与健康献血者 (0/20)比较有显著性差异 (P< 0.01).其中 TNM分期Ⅰ和Ⅱ期患者中血清 p53抗体阳性率为 25%( 5/20),Ⅲ和Ⅳ期为 72.2%( 13/18),表明血清 p53抗体阳性率与食管癌 TNM分期有关 (P< 0.05).细胞分化好、中等、差的患者血清 p53抗体阳性率分别为 21.5%( 3/14)、 50%( 6/12)、 75%( 9/12),显示血清 p53抗体阳性率与食管癌细胞分化程度有关 (P< 0.05).血清 p53抗体阳性患者对 DDP、 5-FU、 ADM敏感的比率( 11.1%、 16.7%、 5.6%)显著低于血清 p53抗体阴性患者( 60%、 45%、 45%; P值分别 < 0.01、 < 0.05、 < 0.05).结论:血清 p53抗体可以作为预测食管癌化疗敏感性的参考指标之一.     

p53基因网络的研究进展

肿瘤抑制基因p53与其上、下游功能相关基因组成了一个复杂的基因网络。p53基因位于人染色体17q13．1区带,编码的野生型p53蛋白包含N—末端的转录激活结构域、DNA结合结构域、四聚体化结构域和C—末端调节域。p73、p5l、p63等基因由于在结构上与p53基因具有同源性,因而被归为p53基因家族。p53是联系不同遗传应急和细胞应答的中间环节,离子辐射、化疗药物及异常的细胞生长信号均能刺激p53基因表达。p53表达升高后,可通过p53-mdm2、p14^ARF—mdm2环路对p53表达水平进行精确调节,p53功能的发挥还同时需要p33^MG1b基因的协同作用。磷酸化和乙酰化是细胞内调节p53活性功能的主要途径。p53可以调控下游多种基因表达,其功能主要表现在阻滞细胞周期、促进细胞凋亡、维持基因组稳定性和抑制肿瘤血管生成四个方面。认识p53基因网络的功能将有助于理解p53及其相关基因间的具体作用机制。     

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     

Bcl—2和p53基因蛋白在阴茎癌中的表达

为了研究Ｂｃｌ－２和ｐ５３基因蛋白与阴茎癌的关系，应用ＰＡＰ免疫组化法对４６例阴茎癌组织中Ｂｃｌ－２和ｐ５３基因蛋白进行检测。结果显示，正常鳞状上皮基底细胞Ｂｃｌ－２蛋白表达阳性，４６例阴茎癌中有３８例（８２．６％）Ｂｃｌ－２蛋白表达阳性，有１１例（２３．９％）ｐ５３蛋白表达阳性。提示两种癌基因蛋白的过度表达参与了阴茎癌的发生发展过程。     

系统免疫炎性反应指数对乳腺癌新辅助化疗病理完全缓解的预测作用及其与p53的关系

目的探讨系统免疫炎性反应指数(SII)对乳腺癌新辅助化疗(NAC)病理完全缓解(pCR)的预测作用及其与p53的关系。方法回顾性分析387例接受新辅助化疗及手术的女性乳腺癌患者临床病理资料。Logistic回归模型进行单因素和多因素分析。结果 72例(18.6%)患者接受新辅助化疗后获得了pCR,其中低SII组48例,高SII组24例;p53阴性组39例,阳性组33例。单因素分析显示:pCR与临床T分期、激素受体(HR)状态、人表皮生长因子受体2(HER2)、Ki67值、分子分型、p53及SII相关(均P<0.05);多因素分析显示:临床T分期、Ki67值、分子分型、p53及SII是影响乳腺癌患者pCR的独立预测因素。p53阴性的低SII组患者pCR率高于其他组。结论 SII是乳腺癌新辅助化疗病理完全缓解的独立预测因素,具有简单方便及重复性高等特点,p53阴性的低SII组患者pCR率高。     

乳腺癌p53基因表达与辅助化疗的关系

目的 探讨乳腺癌ｐ５３基因表达与辅助化疗的近期临床疗效的关系。方法 采用Ｓ－Ｐ法对１０８例乳腺癌做免疫组化染色，观察各型乳腺癌中ｐ５３基因的表达及与术前化疗疗效的关系，并进行临床相关因素分析。术前化疗采用ＣＭＦ方案（ＣＴＸ６００ｍｇ／ｍ＾２，静脉推注，第１天和第８天；ＭＴＸ３００ｍｇ／ｍ＾２，静脉推注，第１天和第８天；５－Ｈｕ５００ｍｇ／ｍ＾２静脉滴注，第１天和第８天）１个疗程化疗后，进行手术。结     

Impact of Neoadjuvant Chemotherapy on Pathologic Response in Patients With Upper Tract Urothelial Carcinoma Undergoing Extirpative Surgery

Background

Neoadjuvant chemotherapy (NAC) has been increasingly adopted in the management of high-grade upper tract urothelial carcinoma (UTUC), largely extrapolating from level I evidence in urothelial carcinoma of the bladder. Studies examining pathologic outcomes in patients with UTUC receiving NAC are mostly limited to retrospective, single-center studies with limited sample size, with results of a phase II trial recently presented. Hypothesizing that NAC is associated with improved pathologic response (PR), we compared pathologic outcomes in patients with high-grade UTUC who did and did not receive NAC before extirpative surgery.

雌孕激素受体、p53、C-erbB-2在子宫内膜癌的表达及临床意义

[目的]探讨ER、PR、p53、C-erbB-2在子宫内膜癌组织中的表达及其临床意义.[方法]采用SP法对32例子宫内膜癌和12例正常增生期子宫内膜标本进行ER、PR、p53、C-erbB-2的检测.[结果]正常增生子宫内膜与子宫内膜癌组织中ER、PR、p53、C-erbB-2表达阳性率分别为91.67%、83.33%、8.33%、16.67%及46.88%、4063%、53.13%、62.5%,两者比较有明显差异(P＜0.05).子宫内膜癌ER、PR表达在G1与G3之间差异有高度显著性(P＜0.001),G1与G2之间差异有显著性(P＜0.05),但与临床分期无关(P＞0.05);p53、C-erbB-2表达在Ⅰ期与Ⅲ期之间、G1与G3之间差异有显著性(P＜0.05).[结论]ER、PR、p53、C-erbB-2的异常表达可能在子宫内膜癌的发生、发展过程中起着重要作用,ER和PR的表达可作为内分泌治疗的参考指标.