可疑肺癌病人纤支镜检查标本的p53基因突变检测

探讨行支镜检查标本的Ｐ５３基因突变检测用于肺癌早期诊断的可行性。方法：采用聚合酶链反应－单链构象记性分析银染技术,对３５例怀疑为肺癌病人的８５份纤支镜检查标本行Ｐ５３基因５－８号外显子突变检测。结果发现１０例病人有Ｐ５３基因突变（２８．６％）,其中以６号外显子突变率最高（１７．１％）。     

Detection of p53 gene mutation of bronchoscopic samples in the patients suspected to lung cancer

Objective: To determine the feasibility of detecting p53 gene mutations for early diagnosis of lung cancer using the samples from bronchoscopic examination. Methods: Point mutations of the exon 5 – 8 of p53 gene were detected in 85 bronchoscopic samples of 35 patients suspected to be lung cancer using silver staining PCR-SSCP. Results: p53 gene mutations were founded in 10 of 35 patients(28.6%). The incidence of p53 gene mutations (14.9%) was obviously higher than the cytological positive incidence(2.9%) in samples of sputum, bronchoalveolar lavage and brush, especially for the sputum(27.7%). In the bronchoscopic biopsy specimens, the incidence of p53 gene mutations (12.5%) was lower than that of pathologic positive result (50.0%). However, in view of all the bronchoscopic samples, there was no statistically difference between cytopathologic positive results (11.8%) and the incidence of p53 gene mutations (14.1%). Although the p53 mutations were most common in the samples from the patients bronchoscopically manifested as neoplasm compared with other manifestations, there was no statistical difference. It is valuable to notice that 3 patients with p53 gene mutation merely presented as bronchial inflammation in bronchoscope. Conclusion: Results indicated that the value of detecting p53 gene mutation for the diagnosis of lung cancer using the bronchoscopic samples was more superior to cytological examination and detection of p53 gene mutations in post-bronchoscopic sputum was easy and effective, may be used as a valuable method for early diagnosis of lung cancer. This work was supported by the Research Foundation of the Ministry of Public Health of PR China (No. 94-1-316).     

乳腺增生病p53基因第8外显子突变及p53蛋白表达

目的：探讨p53基因在乳腺癌发生早期的作用。方法：用免疫组化检测36例乳腺单纯增生，31例不典型增生，30例乳腺癌组织中p53蛋白表达，用PCR－RFLP检测p53基因第8外显子第278密码子突变。结果：乳腺单纯性增生，不典型增生和乳腺癌中p53蛋白表达率分别为0，22．6％，46．7％。p53基因第8外显子的突变率分别为0，3．2％，10．0％，均为杂合子突变。结论：乳腺癌不典型增生中存在p53蛋白表达和该基因第8外显子突变，该突变可能在乳腺增生病向乳腺癌进展过程中起一定作用。     

建立显微分离细胞技术并检测胃癌细胞内p53基因突变

目的 获取较纯的微量胃癌细胞并检测ｐ５３基因的突变。方法 在显微镜下,直接分离出胃癌细胞中微小癌灶内细胞,并应用单链构象多态（ＳＳＣＰ）技术分析该微量细胞中ｐ５３基因的突变。结果 在１７１例胃癌组织的石蜡标本中,有７０例获得可靠结果,包括６例早期胃癌和６４例进展期胃癌,该方法总成功率为４１．０％。结论 显微分离细胞技术十分有利于观察癌前病变、原位癌及浸润的基因变化;该方法直接证明早期胃癌细胞中ｐ５     

p53基因突变与人非小细胞肺癌临床病理生理分析

目的 探讨ｐ５３基因点突变与人非小细胞肺癌临床生理特征的联系。方法 应用聚合酶反应－单链构象多态性分析方法（ＰＣＲ－ＳＳＣＰ０检测原发性非小细胞肺癌癌组织的ｐ５３基因第５～８外显子点突变。结果 ４０例肺癌组织中１９例（４７．５％）有点突变发生,８例良性肿瘤组织均无ｐ５３基因点突变发生,点突变发生与病理分期和淋巴结转移有明显关系（Ｐ〈０．０２５）,结论ｐ基因估变在非小细胞肺癌的发生和进展中可能起重要作用。     

高分辨熔解曲线法检测非小细胞肺癌p53基因的突变

背景与目的 p53基因与人类多种肿瘤相关,突变型具有致癌作用,主要分布在外显子5-8.本研究旨在建立高分辨熔解曲线(high resolution melting,HRM)检测非小细胞肺癌(non-small cell lung cancer,NSCLC)患者p53基因突变的方法,探讨p53基因突变的特点及其在NSCL...     

Titration of serum p53 antibodies in patients with gastric cancer: a single-institute study of 40 patients

Background Alterations of the p53 tumor suppressor gene are the most commonly observed genetic abnormalities in many different types of human malignancies. The accumulation of mutant p53 often leads to the production of p53 antibody (p53-Ab) in the sera of patients with various cancers. To evaluate the clinical implications of serum p53-Abs in patients with gastric cancer, we compared p53-Abs with conventional tumor markers such as carcinoembryonic antigen (CEA) and carbohydrate antigen (CA)19-9. Methods Serum samples were obtained preoperatively from 40 patients with histologically confirmed gastric adenocarcinoma, including 28 (70%) patients in stage Ia. The serum p53-Abs were assessed by enzyme-linked immunosorbent assay, using a new version of a highly specific, quantitative p53-Abs Kit (MESACUP Kit II). Results p53-Abs were detected in 6 (15%) of 40 patients with gastric cancer, including 3 patients with early gastric cancer. Seven (17.5%) of the 40 patients were positive for CEA in serum. However, none of 7 patients with high CEA levels were positive for p53-Abs. No significant correlation of p53-Abs with patient age, sex, pathological parameters, tumor markers such as CEA and CA19-9, or poor survival (P = 0.116) was observed. Conclusion Although we employed the latest version of the p53-Abs Kit, the sensitivity of serum p53-Ab in gastric cancer patients was relatively low. No correlation was found between the presence of p53-Ab and the staging of cancer or survival. However, serum p53-Ab was detectable in patients with gastric cancer even in the early stages of disease. In addition, it may be independent of CEA and CA19-9.     

贲门癌端粒酶活性表达及与p53基因突变关系的研究

Objective: To study the relationship of the telomerase activity and the p53 gene mutation in cardiac cancer.Methods: Telomerase activity and the p53 gene mutation were detected in 46 case of cardiac cancer, peri-cancerous and 30 case of normal mucosa by TRAP-ELISA and PCR-SSCP. Results: The rate of expression of telomerase activity in cardiac cancer, peri-cancerous and normal mucosa were 82.61％ (38/46), 43.48％ (20/46) and 13.33％ (4/30) respectively. The rate of Exon5→8 of p53 gene mutation were 39.13％ (18/46), 4.35％ (2/46) and 0.00％ respectively. There was significant differ ence between group cancer and without cancer (P ＜ 0.01). Mean of (A) value of telomerase is 1.89 ± 0.41 in cancer group and were 1.49 ± 0.43, 0.54 ± 0.45 respectively in peri-canvcerous and normal mucosa, there were significant differences in cancer group and group of without cancer (P ＜ 0.05). The rate of p53 gene mutations in group of expression of telomerase activity was 44.74％ (17/38), and 12.50％ (1/8) in without expression of telomerase activity. There were significant differences between the two groups. Conclusion: The rate of expression of telomerase activity and mean of (A) value of telomerase in cardiac cancer were obviously higher than without cancer, which indicating telomerase activity was closely related with the occurrence of cardiac cancer. P53 gene mutation in cardiac cancer were higher than the tissue of without cancer, and the rate of p53 gene mutation in telomerase activity were obviously higher than the group of without cancer. This shows the p53 gene mutation can loss of function of suppressing cancer and prompt telomerase activity and cause the cardiac cancer.     

胃癌中p16基因缺失与突变的研究

目的：探讨p16基因外显子2的缺失和突变与胃癌发生发展的关系.方法：应用新鲜组织标本基因组DNA抽提、PCR-SSCP分析的方法,对30例胃癌及癌旁组织中p16基因外显子2的缺失和突变进行检测.结果：胃癌组织样本中p16基因外显子2的缺失率为10.00%,突变率为10.00%,两者之和为20.00%,癌旁组织样本中未发现缺失和突变,统计学分析有显著性差异（P〈0.01）.结论：p16基因外显子2的缺失和突变与胃癌的发生具有一定的相关性.     

修饰型微卫星不稳定性与散发结直肠癌p53基因点突变的相关性

目的 高频度微卫星不稳定性被认定为DNA错配修复缺陷的标志,但既往研究发现一个显著矛盾,即在高频度微卫星不稳定结直肠癌中,p53突变率较一般结直肠癌低.研究旨在确认该矛盾的存在并试图阐明其机制.方法 对180例散发结直肠癌采用高分辨率荧光标记微卫星分析法检测微卫星位点稳定性,PCR扩增直接测序检测p53突变.结果 微卫星不稳定性呈现修饰型和跳跃型两种变化.低频度微卫星不稳定性均呈现修饰型而无跳跃型变化;高频度微卫星不稳定性均检出了跳跃型变化,一部分也并存修饰型变化.微卫星不稳定与肿瘤部位及分化程度明显相关,p53突变与肿瘤分化明显相关.高频度微卫星不稳定肿瘤未检出p53突变,而低频度微卫星不稳定肿瘤p53突变率较高.结论 低频度微卫星不稳定性呈现的修饰型微卫星位点长度变化可能是DNA错配修复缺陷的表型;此表型与提高的碱基置换突变率有关.单纯DNA错配修复缺陷可能不足以导致微卫星不稳定性的跳跃型变化,高频度微卫星不稳定的真正原因仍有待阐明.     

EBV相关性胃癌罕见p53基因突变的可能机制与意义

2014年癌症基因组图谱（The Cancer Genome Atlas,TCGA）首次将胃癌从分子水平分为四型,其中EB病毒（Epstein-Barr virus,EBV）感染型即EBV相关性胃癌（EBV-associated gastric cancer,EBVaGC）患者,可能是免疫治疗的适宜群体。在包括胃癌在内的大部分肿瘤中p53基因突变率最高,但在EBVaGC中p53基因突变率却远低于EBV阴性胃癌（EBV-negative gastric cancer,EBVnGC）。可能机制为:EBV感染是EBVaGC形成的早期事件;野生型p53蛋白与病毒即刻早期蛋白BZLF1（Z）相互作用,维持EBV潜伏感染状态和早期复制;病毒复制后期,野生型p53蛋白可在病毒产物的作用下通过泛素化等途径被降解,以上或可表明p53基因野生型对EBVaGC形成的重要性。而EBV感染诱导炎症反应,肿瘤组织中大量淋巴细胞浸润,基因组高突变率及PD-L1扩增的特征使其可能成为免疫治疗的适宜群体,也说明免疫微环境在肿瘤发生发展中的重要作用。而在EBVnGC中,多种因素导致p53基因突变率较高,使其失去正常的抑癌功能而导致肿瘤发生。本文就EBVaGC中罕见p53基因突变这一现象的可能机制进行综述。      

肝细胞癌p53基因突变初步研究

本文应用快速银染多了矣酶链反应单链构像多态（ＰＣＲ－ＳＳＣＰ）方法检测了３０例肝细胞癌（ＨＣＣ）组织中ｐ５３基因变异情况。结果１３例癌组织中有异常电带，其中２闰于第５外显子，各有３例位于第６和第７外显子，位于第８显子有５例，ｐ５３基因变异的病例乙型肝炎表面抗原均阳性，实验结果表明：本技术能有效检测出基因突变；肝细胞癌中ｐ53基因突变率较高且有多个位点；肝细胞癌ｐ５３基因突变可能与乙型肝炎病毒感染有关     

p53 mutations in gastric cancers from Taiwan

Mutations of the p53 gene were investigated in 80 surgical specimens of primary gastric cancer by polymerase chain reaction single-strand conformation polymorphism (PCR-SSCP) analysis. Mutations were detected in 18 tumors (22.5%) and localized to exons 5, 7 and 8. Mutations did not follow a random distribution among different subtypes, but instead clustered in the group of papillary adenocarcinomas, in which 7/12 (58.3%) cases were mutated. Positivity for p53 mutation was significantly higher in intestinal-type (37.5%) than in diffuse-type carcinomas (12.5%). These results suggest that gene alterations of p53 are not rare and may participate in the carcinogenesis of intestinal-type carcinomas of the stomach. Twenty of 21 p53 mutations were represented by single nucleotide changes, mostly missense mutations (19 events) and one nonsense mutation. Transversional mutations constitute the majority of p53 mutations (65%) and only 20% of mutations show G:C to A:T transitions. It is possible that the etiologies of gastric cancer in different geographical areas are different.     

The p53 tumor suppressor gene in breast cancer

Summary Alterations of the p53 tumor suppressor gene are the most common genetic changes found so far in breast cancer, suggesting that the gene plays a central role in the development of the disease. p53 functions as a negative regulator of cell growth, and alterations in the gene lead to loss of this negative growth regulation and more rapid cell proliferation. A number of independent groups using different methods of detection have shown that p53 alterations are associated with more aggressive tumor biologic factors and a poorer prognosis in breast cancer patients. Because of its possible role in the regulation of apoptosis and response to DNA damage, p53 status could also be a predictive marker for response to hormonal or chemotherapy.     

PROMOTER HYPERMETHYLATION OF p16 GENE IN PRE- AND POST-OPERATIVE PLASMA OF PATIENTS WITH GASTRIC ADENOCARCINOMA

Objective: To detect promoter hypermethylation of p16 gene in matched pre- and post-operative plasma of patients with gastric adenocarcinoma for evaluating the effectiveness of therapeutic intervention. Methods: Tissue samples, pre- and post-operative plasma of 84 patients were collected. Plasma of 15 healthy people was collected as control. After sodium-bisulfite treatment, extracted DNA was amplified for p16 promoter by methylation-specific polymerase chain reaction (MSP). The PCR products were detected by both gel-ethidium bromide electrophoresis and high performance liquid chromatogram (HPLC). Results: Among 84 patients, p16 hypermethylation was detected in 26 (31.0%) cancer tissues and 2 (0.02%) tumor-adjacent tissues and 12 (14.3%) pre-operative plasma, while negative in plasma of healthy people. For positive plasma cases, the paired tumor tissues were confirmed to be methylated.Within available 30 pairs of matched pre- and post-operative plasma, 6 pre-operative plasma was positive, and only 1 of 6 plasma remained hypermethylated after surgery. The results detected by HPLC exactly matched those by gel-electrophoresis. Conclusion: The alteration of status of p16 hypermethylation in post-operative plasma is considered the consequences of surgical intervention. Although p16 hypermethylation has no role in pre-operative staging of gastric cancer, detecting hypermethylated p16 in plasma could be utilized in monitoring patients after surgery.     

检测外周血中p53基因突变诊断肺癌微转移的临床意义

目的 探讨检测肺癌患者外周血中p53基因突变的诊断意义。方法 应用PCR－SCCP方法，对28例肺癌患者，8例良性肺疾病患者和10例健康人外周血中的p53基因突变进行检测。结果 在28例肺癌患者外周血标本中，4例检测出p53基因突变，阳性率为14．29％。其中鳞癌1例，腺癌1例，小细胞癌2例；Ⅱ期患者1例，Ⅲ期1例，Ⅳ期2例。8例良性肺疾病患者和10例健康人的外周血均未检测出p53基因突变。结论 检测外周血中p53基因突变有助于肺癌的诊断和肺癌病理分期。     

胃癌患者p53基因甲基化的研究

作者应用限制性内切酶ＨｐａⅡ和ＭｓｐⅠ酶切胃癌组织及正常胃组织ＤＮＡ，经ＰＣＲ扩增ｐ５３基因第５外显子，琼脂糖凝胶电泳分析其电泳图谱，比较胃癌组织及正常胃组织ｐ５３基因第５外显子特定序列５′－ＣＣＧＧ－３′位点甲基化差异。结果显示：１５例胃癌组织中１２例ｐ５３基因第５外显子出现高甲基化状态，而１０例正常胃组织为低甲基化状态，结果提示，ｐ５３基因高甲基化状态与胃癌发生有关。     

胃癌组织中p53基因突变及p53和mdm2蛋白表达的研究

目的探讨mdm2和p53基因异常在胃癌发生发展中的作用以及两者相关性。方法应用免疫组化技术检测58例胃癌组织以及相应癌旁组织中mdm2和p53蛋白的表达;PCR-SSCP银染技术检测p53基因exon5~8突变情况。结果胃癌组p53和mdm2蛋白阳性率分别为86·21%(50/58)和29·31%(17/58),癌旁组织组p53和mdm2蛋白均为阴性,胃癌组p53和mdm2蛋白阳性率明显高于癌旁组织组,两两间差异有统计学意义,P=0·0000、P=0·0001。胃癌组织中p53和mdm2蛋白表达率与肿瘤大小、组织学类型、分化程度、淋巴结转移以及患者年龄等无显著相关性,P>0·05。mdm2蛋白阳性表达与p53蛋白过表达呈显著正相关,χ2=11·1839,P=0·0008,r=0·4391。2例胃癌组织检测到p53基因突变,突变均位于exon5,58例相应癌旁组织均未检测到p53基因突变。结论mdm2和p53蛋白异常表达与胃癌发生有关,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,mdm2蛋白在胃癌发生发展中的作用可能与p53蛋白密切相关。     

Prognostic significance of p53 gene alterations in node-negative breast cancer

Summary Mutations in the p53 gene can play a role in the transformation of normal to malignant cells. Because these mutations are more frequently reported later in the course of transformation, their presence could reflect a greater malignant potential of the tumor and, thus, an increased probability of metastasis and recurrence after local therapy. In a pilot study using single-stranded conformation polymorphism analysis (SSCP), 200 node-negative breast tumors were examined for mutations in the region encompassing exons 5 through 9 of the p53 gene. Exons 5 through 9 were tested because they contain 80–90% of known p53 gene mutations. The tumors ranged in size from 1 to 3 cm. 28 tumors were found to have an abnormal band pattern on both initial and repeat analysis. 4 of these tumors were sequenced; 3 contained a p53 mutation and the 4th had a rare neutral polymorphism. Disease-free survival (DFS) at 5 years for women with tumors having an abnormal SSCP analysis was 57% (± 10%), compared to a 79% (± 3%) DFS for the group with a normal pattern. By the log rank test, this difference was highly significant, p 0.01. The relative risk of recurrence for the group with an abnormal SSCP pattern was 2.2. In a multivariate analysis including ER, PgR, ploidy, S-phase, age, and tumor size, an abnormal p53 by SSCP analysis and patient age were the only factors that independently predicted DFS at 5 years. Conclusion: Women with node-negative breast cancer who have tumors with alterations in the p53 gene, as indicated by SSCP analysis, have a significantly poorer prognosis and a higher rate of relapse at 5 years. The prognostic significance is maintained in a multivariate analysis including many established prognostic factors.We regret to report that Dr. McGuire died March 25, 1992, while this work was in progress.     

抑癌基因p53在胃癌组织的表达及临床意义

目的：探讨ｐ５３基因在胃癌的表达与临床、病理因素及预后的关系,探索ｐ５３基因异常表达在胃癌发生过程中的作用。方法：使用抗ｐ５３蛋白单克隆抗体ＤＯ－７,对９９例人胃癌组织ｐ５３的表达进行免疫组化研究。结果：４８例胃癌组织ｐ５３基因表达阳性（４９％）。ｐ５３基因表达与胃癌的大体类型、分化工、淋巴结转移等指标均无明显关系。在１０例不典型增生的癌旁组织中,２例呈阳性反应;在４例有肠上皮化生的癌旁组织中及其