p53基因cDNA突变及其蛋白高表达与大肠癌预后关系

１００份大肠癌组织，用ＲＴ－ＰＣＲ－ＳＳＣＰ检测Ｐ５３基因ＣＤＮＡ突变；ＰＡｂ１８０１单抗免疫组化检测Ｐ５３基因蛋白搞表达并对大肠癌术对后病人作５年生存随访，比较上述２结果与大肠癌预后的关系，１００例大肠癌中，ＲＴ－ＰＣＲ－ＳＳＣＰ显示５１例大肠癌Ｐ５３基因ＣＤＮＡ突变，ＰＡｂ１８０１阳性率６２％，Ｐ５３基因ＣＤＮＡ突变和Ｐ５３基因蛋白高表达与Ｄｕｋｅｓ分期无关，Ｐ５３基因ＣＤＮＡ突变与Ｐ５３基因     

骨髓增生异常综合征和急非淋血血病中癌基因及抑癌基因扩…

应用核酸杂交技术分析了癌基因ｃ－ｍｙｃ、Ｎ－ｒａｓ和抑癌基因Ｐ５３在骨髓增生异常综合征（ＭＤＳ）和急非淋白血病（ＡＮＬＬ）中的扩增情况。结果发现，有３例（３３％）的ＭＤＳ存在Ｐ５３抑癌基因的２倍扩增，本实验中Ｐ５３抑癌基因的扩增发生在ＭＤＳ的较晚期阶段；１例ＡＮＬＬ中存在癌基因ｃ－ｍｙｃ和抑癌基因Ｐ５３的共扩增，且发现扩增与ＭＤＳ的分型及ＡＮＬＬ的临床病情有一定的相关性。     

胃癌DNA非整倍体的临床意义及其与癌基因扩增的关系

对４１例原发性胃癌用流式细胞光度术分析，结果５８．５％为非整倍体瘤，非整倍体与胃癌的局部淋巴结转移明显相关（Ｐ〈０．０５）。癌基因ｃ－ｍｙｃ，ｃ－ｅｒｂＢ－２，表皮生长因子受体基因扩增与非整倍体之间存在相关性（Ｐ〈０．００５，ｒ＝０．８０２）。     

PCR-SSCP在恶性血液病N-ras癌基因点突变检测中的应用

目的：检测血液系统肿瘤中Ｎ－ｒａｓ癌基因点突变的活性。方法：采用ＰＣＲＳＳＣＰ技术分析了２８例恶性血液病Ｎｒａｓ基因的突变活性，包括：ＡＮＬＬ６例，ＡＬＬ１２例，ＨＤ２例，ＮＨＬ３例，ＭＤＳ５例。结果：２８例中ＰＣＲＳＳＣＰ检测与正常对照，发生阳性者４例（１４．６％），其中ＡＬＬ１例（８．３％）、ＡＮＬＬ１例（１６．６％）、ＭＤＳ２例（４０％）。４例中有２例临床缓解后持续阳性，１例为ＡＬＬ患者，于骨髓移植后１０４ｄ复发死亡。１例ＭＤＳ患者转化为急性白血病，另２例临床缓解后３个月检测转阴，其中１例为ＡＮＬＬ，１例为ＭＤＳ。结论：ＰＣＲＳＳＣＰ方法可作为一种癌基因点突变检测手段常规应用于临床，但值得注意的是，ＰＣＲＳＳＣＰ方法只能提供分析区域是否存在突变点，而不能提供突变性质的信息     

肝癌病人门脉海绵变性的血管造影和病理形态学研究

作者对１８０例肝癌病人做了腹腔动脉干和肠系膜上动脉造影，其中９８例造影后做了肿瘤切除术和病理检查。对这些病例分析，发现门静脉阻塞和门脉内无向肝性及离肝性血流，是肝内门脉海绵变性（ＣＴＰＶ）形成的重要因素。同时认为门脉主干癌栓伴有ＣＴＰＶ者预后较好，可作栓塞治疗。文中还对ＣＴＰＶ的形态结构及其形成机制进行了探讨。     

用PCR－F、PCR－SSCP对骨髓移植植入状态的观察

应用ＨＬＡ－ＤＱＡ、ＤＲＢ、ＤＰＢ、ＤＱＢ位点聚合酶链反应一指纹图（ＰＣＲ－Ｆ）和聚合酶链反应一单链构象多态性（ＰＣＲ－ＳＳＣＰ）方法，对５例ＨＬＡ血清学配型一致的异基因骨髓移植病人，分别于移植后３５ｄ左右进行了植入状态的观察。此方法不受供、受体性别和血型的影响，具有灵敏、准确、快速、简便等优点，其中４例以特殊带型为异基因骨髓移植提供了直接的植入证据．     

CTAP与SMA-P评价肝癌血管内治疗前门脉血流的对比研究

目的：研究经肠系膜上动脉门脉造影ＣＴ（ＣＴＡＰ）在评价肝癌患者的门静脉血流方面是否优于经肠系膜上动脉门脉造影（ＳＭＡ－Ｐ）。方法：２１例肝癌患者在血管内治疗前先后行ＣＴＡＰ及ＳＭＡ－Ｐ，进行对比研究。结果：１３例ＣＴＡＰ与ＳＭＡ－Ｐ评价结果一致；７例评价结果基本一致，其中６例由于碘油重叠或血液层流ＳＭＡ－Ｐ显示欠佳者ＣＴＡＰ都能清晰显示，其中１例段级门脉阻塞，ＣＴＡＰ显示更确切的解剖部位；１例评价结果不一致，门脉高压影响ＳＭＡ－Ｐ对门脉的显示，但ＣＴＡＰ仍能清晰显示。结论：ＣＴＡＰ较ＳＭＡ－Ｐ能更准确地反映肝癌患者的门脉血流。     

溴酚蓝结合蛋白结构及稳定性的研究

在早期对溴酚蓝结合蛋白（ＢＰＢＢＰ）的研究中，我们确定了其在电泳谱中的位置及分子量。目前进行的实验中，我们从不同患者血清中ＢＰＢＢＰ的存在及正常人的血清中ＢＰＢＢＰ的结构和稳定性等方面对ＢＰＢＢＰ进行了测定。测定的结果：（１）在不同患者血清中都不同程度地存在着ＢＰＢＢＰ，这为寻求基因药物载体提供了新思路。（２）不同ｐＨ下，紫外－可见光连续光谱的结果说明ＢＰＢＢＰ与溴酚蓝发生了化学键的结合，并结合稳定；只有当ＢＰＢＢＰ的二级结构被破坏时，方可同溴酚蓝解离；溴酚蓝结构中的发色团也参与了结合，同时ＢＰＢＢＰ与溴酚蓝的结合需要电荷的存在；（３）荧光光谱和荧光淬灭及温度淬灭的结果：ＢＰＢＢＰ中位于分子外部的Ｔｒｐ，Ｔｙｓ，Ｐｈｅ占Ｔｒｐ，Ｔｙｓ，Ｐｈｅ总量的６０％，内部的占４０％；在７５℃时ＢＰＢＢＰ发生热变性，说明ＢＰＢＢＰ的热稳定性较好，这也是基因药物的应用基础之一。     

用银染PCR—SSCP方法检测肺鳞癌组织标本中P16基因和E1.β …

目的：检测肺鳞癌组织中ｐ１６基因和Ｅ１．β外显子的异常改变，进一步观察该基因在肺鳞癌组织细胞周期调节紊乱中的异常，探讨肺鳞癌发生，发展的分子机制。方法：采用银染ＰＣＲ－ＳＳＣＰ方法对常规石蜡包埋肺鳞癌标本中的ｐ１６基因和Ｅ１．β外显子异常进行检测，结果与结论：１１例免疫组化检测ｐ１６表达阴性的肺鳞癌标本中，４例有异常电泳带，其中，第１，２外显子各１例，第３外显子２例，从６例ｐ１６蛋白阳性肺癌组织检     

部分性脾栓塞术治疗地中海贫血的长期疗效观察

目的 评价部分性脾栓塞（ｐａｒｔｉａｌ ｓｐｌｅｎｉｃ ｅｍｂｏｌｉｚａｔｉｏｎ，ＰＳＥ）治疗地中海贫血的长期疗效。方法 对１９９３年５月在我院采用ＰＳＥ术治疗的７５例地中海贫血患者进行随访，随访指标主要为术后血红蛋白浓度、输血次数、输血量。选取资料完整的３０例患者进行分析。其中α型地中海贫血８例，β型地中海贫血２２例。结果 ３０例地中海贫血患者中，有２６例患者ＰＳＥ术后输血量减少，血红蛋白浓度升     

聚合酶链反应单链构象多态性分析对人非小细胞肺癌p53基因突变的检测

目的：探讨ｐ５３ 基因突变在中国人非小细胞肺癌发生中的作用。方法：利用聚合酶链反应单链构象多态性分析（ＰＣＲ－ＳＳＣＰ）方法,对４８ 例临床肺癌标本（以相应远离肺癌的正常肺组织为对照）进行ｐ５３ 基因突变检测。结果：（１）ｐ５３ 基因突变频率为５６．２５％ （２７／４８）;（２） ｐ５３ 基因突变频率与肿瘤组织类型、淋巴结转移、年龄及性别无统计学相关;（３） ｐ５３ 基因突变频率与肿瘤分化程度存在明显负相关（Ｐ＜ ０．０５）;（４）吸烟者ｐ５３ 突变频率高于非吸烟者（分别为５８．３％ 和３３．３％ ）,但无统计学差异;（５） ６／７ 具有组织浸润及远处转移的肿瘤标本存在ｐ５３ 突变。结论：ｐ５３ 基因突变在中国人肺癌发生过程中发挥重要作用,在肺癌中存在ｐ５３ 基因突变提示患者预后不良;而且ｐ５３基因突变与吸咽及肺癌高转移性相关。     

p53 status in radiation-induced soft-tissue sarcomas

Background

Following therapeutic irradiation after a latency period of many years radiation-induced tumors, often sarcomas, can arise. Results of radiation-induced DNA damage can be 1. p53 over-expression, inducing growth arrest or apoptosis, and 2. occurrence of mutations, frequently including the p53 gene, as one molecular promotor for carcinogenesis. We were interested whether radiation-induced sarcomas are associated with alterations of the p53 status.

Material and Methods

Samples from 11 radiation-induced soft-tissue sarcomas (STS) were studied by a non-radioactive PCR-SSCP sequencing analysis and by immunohistochemistry with five antibodies for their p53 status.

Results

A tumor of one patient possessed a G→A transition in codon 280 (exon 8). Of 11 tumors, 9 showed nuclear p53 positivity, detected by monoclonal antibody DO-1. Of these 9 patients. 7 died during the observation period, whereas the 2 patients with DO-1 negative tumor samples are still alive.

Conclusions

p53 over-expression and p53 mutation occur in radiation-induced STS. p53 status is expected to have prognostic impact for radiation-induced STS.     

Analysis of loss of heterozygosity of the tumor suppressor genes p53 and BRCA1 in ovarial carcinomas

BACKGROUND/AIM: Among the genes involved in ovarian carcinogenesis, there has been increased interest in tumor-suppressor genes p53 and BRCA1. Both of the genes make control of cell cycle, DNA repair and apoptosis. The p53 is a "genome guardian" inactivated in more than 50% of human cancers, while BRCA1 mutations are found mostly in breast and ovarian cancer. The aim of this investigation was to establish the frequency of loss of heterozygosity (LOH) in the regions of the genes p53 and BRCA1 in ovarian carcinomas, and to analyze the association of LOH with the disease stage and prognosis. METHODS: We analyzed 20 patients with a confirmed diagnosis of epithelilal ovarian carcinoma. DNA for molecular-genetic analysis was extracted from the tumor tissue and blood as normal tissue of each person. Microsatellite markers of the regions of genes p53 and BRCA1 were amplified by PCR method. The determination of allelic status of microsatellites and detection of LOH was performed after PAA gel electroforesis. RESULTS: Both of the analyzed microsatellite markers were informative in 13/20 (65%) cases. In the region of gene p53, LOH was established in 4/13 (30.7%) tumors. One of them had histological gradus G1, one had gradus G2, and two of them had gradus G3, while all were with the International Federation of Gynecology and Obstetrics (FIGO) IIIc stage. In the region of gene BRCA1, LOH was detected in 5/13 (38.5%) tumors. Four of them had histological gradus G2, and one had gradus G3, while by the (FIGO) classification one was with stage Ib, one was with stage IIIb, while the three were with stage IlIc. LOH in both of the analyzed regions was detected in one tumor (7.70), with histological gradus G3 and the FIGO IIIc stage. CONCLUSION: The frequency of LOH in epthelial ovarian carcinomas was 30.7% and 38.5% for p53 and BRCA1 gene regions, respectively. Most of tumors with LOH had histological gradus G2 or G3, and the clinical FIGO stage IIIc, suggesting the association of this occurrence with a later phase of the disease.     

Chronic low dose UV exposure and p53 mutation: Tilting the odds in early epidermal preneoplasia?

Abstract Purpose: This review addresses how mutation of the TP53 gene (p53) and ultraviolet light alter the behavior of normal progenitor cells in early epidermal preneoplasia. Conclusions: Cancer is thought to evolve from single mutant cells, which expand into clones and ultimately into tumors. While the mutations in malignant lesions have been studied intensively, less is known about the earliest stages of preneoplasia, and how environmental factors may contribute to drive expansion of mutant cell clones. Here we review the evidence that ultraviolet radiation not only creates new mutations but drives the exponential growth of the numerous p53 mutant clones found in chronically exposed epidermis. Published data is reconciled with a new paradigm of epidermal homeostasis which gives insights into the behavior of mutant cells. We also consider the reasons why so few mutant cells progress into tumors and discuss the implications of these findings for cancer prevention.     

癌基因与涎腺多形性腺瘤相关性研究

 目的探讨涎腺多形性腺瘤与c-erbB-2,H-ras,p53和bcl-2基因的关系.方法采用免疫组织化学染色和HE染色观察21例多形性腺瘤和24例恶性多形性腺瘤癌基因c-erbB-2,H-ras,p53和bcl-2表达情况,分析c-erbB-2,H-ras,p53和bcl-2基因与涎腺多形性腺瘤的相关性.结果c-erbB-2与p53和bcl-2基因呈正相关(P＜0.05),p53与bcl-2基因呈正相关(P＜0.05),多元回归分析结果表明,用c-erbB-2,H-ras,p53和bcl-2基因对涎腺多形性腺瘤进行判别,bcl-2基因意义最显著.结论涎腺多形性腺瘤是多种癌基因共同作用的结果,c-erbB-2,H-ras,p53和bc-2基因可作为良恶性涎腺多形性腺瘤诊断参考指标.     

食管反流大鼠肿瘤诱发过程中p53基因突变的研究

通过动物实验研究不同反流状态下食管肿瘤诱发过程中 p5 3基因的突变情况。选用SD大鼠进行不同手术 ,制作单纯胃食管反流 (G组 )、单纯十二指肠食管反流 (D组 )、胃十二指肠混合液食管反流 (DG组 )及无反流对照 (C组 )模型 ,于术后 4周开始注射食管致癌剂甲基戊基亚硝胺 (MANA) ,共 15周 ,于术后 2 0、2 6、40周分批取得食管组织 ,进行基因组DNA抽提 ,合成 p5 3基因的第 5、6、7、8外显子的 4对引物 ,进行PCR扩增。扩增产物变性后进行非变性聚丙烯酰胺凝胶电泳 (PCR SSCP) ,电泳后凝胶以硝酸银染色。结果显示PCR扩增未见 p5 3基因缺失。 2 0周时D组及DG组各有 1只 (10 % )标本检测出p5 3突变。此后随时间延长各组突变增加 ,40周时D组 (31 6 % )、DG组 (33 3 % )的突变率显著高于C组 (15 4% )和G组 (11 7% ) ,P均 <0 0 5 ,后两者差异无显著性意义 (P >0 0 5 )。提示十二指肠内容物食管反流可导致食管粘膜上皮p5 3基因的突变率增加 ,这可能是它促进食管肿瘤发生的机制之一。而单纯胃液反流不增加食管的 p5 3基因突变     

Chronic low dose UV exposure and p53 mutation: Tilting the odds in early epidermal preneoplasia?

Abstract

Purpose: This review addresses how mutation of the TP53 gene (p53) and ultraviolet light alter the behavior of normal progenitor cells in early epidermal preneoplasia.

Conclusions: Cancer is thought to evolve from single mutant cells, which expand into clones and ultimately into tumors. While the mutations in malignant lesions have been studied intensively, less is known about the earliest stages of preneoplasia, and how environmental factors may contribute to drive expansion of mutant cell clones. Here we review the evidence that ultraviolet radiation not only creates new mutations but drives the exponential growth of the numerous p53 mutant clones found in chronically exposed epidermis. Published data is reconciled with a new paradigm of epidermal homeostasis which gives insights into the behavior of mutant cells. We also consider the reasons why so few mutant cells progress into tumors and discuss the implications of these findings for cancer prevention.     

Radiosensitization and DNA repair inhibition by pentoxifylline in NIH3T3 p53 transfectants

PURPOSE: To examine the role of p53 mutations in the modulation of DNA repair and radiotoxicity by pentoxifylline. MATERIALS AND METHODS: NIH3T3 murine cells transfected with mutant p53 constructs were examined for the influence of pentoxifylline on radiotoxicity to Co(60) gamma-irradiation by colony assay. DNA repair (0-100 Gy) was measured by constant-field gel electrophoresis. Apoptosis was assessed by flow cytometry with the annexin-V-binding assay. RESULTS: In the two p53 hot-spot mutant cell lines p53-S269R and p53- + 15, the SF(10) radiotoxicity enhancement factors induced by the pentoxifylline were 8.0 and 9.7, respectively. In the p53 deletion mutant p53-DeltaA cell line, the radiotoxicity enhancement factor was 2.6. No radiosensitization was obtained in the untransfected p53 wild-type cell line U-Wt and in the transfected p53 double-wild-type p53-Wt cell line. When pentoxifylline was added after irradiation at the time of maximum G2 block expression, no radiosensitization was observed in any of the five cell lines. Constant-field gel electrophoresis analyses after 20 h of repair showed that pentoxifylline suppresses DNA double-strand break repair in all p53 mutant cell lines, as indicated by repair inhibition factors of 2.0-2.3. No repair suppression was found in the p53 wild-type cell lines. CONCLUSIONS: p53 mutations are a general requirement for radiosensitization by pentoxifylline and the level of radiosensitization depends upon the location of the p53 mutation.