p53 mutations in primary human lung tumors and their metastases

In a total of 26 primary human lung tumors and 60 metastases derived from them, exons 5–8 of the p53 tumor suppressor gene were analyzed by single-strand conformation polymorphism and subsequent direct DNA sequencing of amplified DNA. Mutational inactivation of the p53 gene was identified in four of five squamous cell carcinomas, three of nine adenocarcinomas, and two of nine small-cell carcinomas, the overall incidence being 35%. Point mutations occurred at a similar incidence in exons 5–8, with a preference for G←T transversions. In seven of nine cases (78%), mutations were identical in the primary tumor and all of its metastases, indicating that in lung tumors, p53 mutations usually precede metastasis and that hematogenic and lymphogenic dissemination of tumor cells to other tissues is not associated with a selection against p53 inactivation. In one case, a kidney metastasis had the same mutation as the primary squamous cell carcinoma, whereas a liver metastasis had no mutation, indicating heterogeneity of the primary lung neoplasm and selective metastasis of mutated and nonmutated tumor cells to kidney and liver, respectively. Only in one liver metastasis was a mutation identified that was neither present in the primary lung tumor nor in a kidney metastasis, suggesting that occasionally p53 mutations occur after metastatic spread. © 1994 Wiley-Liss, Inc.     

角化棘皮瘤DNA倍体及p53免疫组化分析

目的　探讨角化棘皮瘤(KA) 的生物学特性。方法　通过细胞图像光度术(ICM) 对20 例KA ( 其中10 例为消退期rKA) 和10 例分化型鳞癌( WDscc) 进行DNA 倍体分析, 并作突变型p53 蛋白免疫组化分析。结果　8 例KA10 例rKA和7 例WDscc 为二倍体, 余为异倍体。KA 组的平均DNA 含量与WDscc 组比较无明显差异( P> 0-05) , 但rKA 组明显低于WDscc 组,差异有显著性( P< 0-002) 。KA 与WDscc 均出现较多的高倍体细胞( > 5c) 。50 % KA, 10 %rKA 和40 % 的鳞癌表达p53 蛋白, 阳性细胞核在KA 和rKA 中主要分布于基底层及基底上层,而在鳞癌中相对较弥漫。正常皮肤不表达p53 蛋白。结论　KA 具有与鳞癌相似的高DNA 倍体;p53 表达阳性及异倍体细胞等恶性肿瘤的特征, 可能与一些罕见的恶性肿瘤自愈病例类似, 在其病变发展过程中存在着一种整体凋亡机制, 有必要对其作进一步的研究     

IGFBP7 is a p53 target gene inactivated in human lung cancer by DNA hypermethylation

Insulin-like growth factor binding protein 7 (IGFBP7) was considered a tumor suppressor gene in lung cancer. However, the mechanism responsible for the downregulation of this gene has not yet been fully understood. In this study, we analyzed the epigenetic inactivation of IGFBP7 expression in human lung cancer. We found that 14 out of 16 lung cancer cell lines showed decreased expression of IGFBP7 compared to control cells by real-time RT-PCR, and 42 out of 90 patients (46.7%) with primary lung tumor exhibited negative staining of IGFBP7 by immunohistochemistry analysis. The IGFBP7 expression could be restored by demethylation agent 5-aza-2′-deoxycytidine (DAC) in 7 cancer cell lines. Methylation status of IGFBP7 was further evaluated by bisulfite sequencing (BS) and methylation-specific-PCR (MSP). It turned out that low expression of IGFBP7 was associated with DNA methylation in lung cancer cell lines and in primary lung tumors (P = 0.019). To explore the regulatory role of p53 on IGFBP7, we transfected a wild type p53 expression vector into lung cancer cell lines H1299, H2228, and H82. Forced expression of p53 increased IGFBP7 expression only in H82 harboring no IGFBP7 methylation, while transfection in combination with DAC induced the expression of IGFBP7 in H1299 and H2228, in which IGFBP7 was methylated. Additionally, treatment with p53 inducer adriamycin (ADR) alone or in combination with DAC increased the expression of IGFBP7 in the 3 cell lines. Our data suggest that IGFBP7 is inactivated in lung cancer by DNA hypermethylation in both lung cancer cell lines and primary lung tumors, and IGFBP7 might be regulated by p53 in lung cancer cells.     

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.     

FAK overexpression and p53 mutations are highly correlated in human breast cancer

Focal adhesion kinase (FAK) is overexpressed in a number of tumors, including breast cancer. Another marker of breast cancer tumorigenesis is the tumor suppressor gene p53 that is frequently mutated in breast cancer. In the present study, our aim was to find a correlation between FAK overexpression, p53 expression and mutation status in a population‐based series of invasive breast cancer tumors from the Carolina Breast Cancer Study. Immunohistochemical analyses of 622 breast cancer tumors revealed that expression of FAK and p53 were highly correlated (p = 0.0002) and FAK positive tumors were 1.8 times more likely to be p53 positive compared to FAK negative tumors [odds ratio (OR) = 1.8; 95% Confidence Interval (CI) 1.2–2.8, adjusted for age, race and stage at diagnosis]. Tumors positive for p53 expression showed higher intensity of FAK staining (p < 0.0001) and higher percent of FAK positive staining (p < 0.0005). From the same study, we evaluated 596 breast tumors for mutations in the p53 gene, using single strand conformational polymorphism and sequencing. Statistical analyses were performed to determine the correlation between p53 mutation status and FAK expression in these tumors. We found that FAK expression and p53 mutation were positively correlated (p < 0.0001) and FAK positive tumors were 2.5 times more likely to be p53 mutation positive compared to FAK negative tumors [adjusted OR = 2.5, 95% CI 1.6–3.9]. This is the first analysis demonstrating a high correlation between FAK expression and p53 mutations in a population‐based series of breast tumors. © 2009 UICC     

肺癌抑癌基因P16，P53的表达及DNA倍体研究

目的　研究P16,P5 3基因在人肺癌中的表达和DNA倍体的关系及意义。方法　以SP免疫组化法检测肺癌组织中P16,P5 3表达 ,图像分析仪测定DNA倍体。结果　P16在肺癌表达阳性率为 5 1.2 % ,低于癌旁组织 (P <0 .0 5 ) ,腺癌P16阳性率最高为 68.8% ,高于鳞癌及未分化癌 (P <0 .0 5 ) ,P5 3在肺癌表达阳性率为 80 .5 % ,明显高于癌旁组织 (P<0 .0 1)其中鳞癌阳性率高于其他组织类型 (P <0 .0 5 ) ,在有淋巴结转移和无淋巴结转移组间及Ⅰ、Ⅱ期与Ⅲ、Ⅳ期两组间 ,P16和P5 3表达阳性率均有显著差异 (P <0 .0 1)。同时发现二倍体P16阳性率 ,P5 3阴性率均显著高于异倍体 (P <0 .0 5 )。结论　P16和P5 3基因异常与肺癌发生有关 ,且在不同类型肺癌发生中的作用不同 ,可作为判断肺癌生物学行为和预后的参考指标。     

c—erbB—2,p53.CEA及PCNA在非小细胞肺癌中的表达

为了探讨ｃｅｒｂＢ２、ｐ５３、ＣＥＡ及ＰＣＮＡ在非小细胞肺癌中的表达及其与临床的关系,采用免疫组化ＬＳＡＢ方法,对２３例非小细胞肺癌进行检测,结果显示,在腺癌的ｐ５３,ＣＥＡ,ｃｅｒｂＢ２表达阳性率分别为４４％,６６％,７７％,鳞癌的表达阳性率分别为２１％,２８％,３５％;鳞癌的阳性表达率明显低于腺癌。ｃｅｒｂＢ２、ｐ５３、ＣＥＡ阳性表达与淋巴结转移无关（Ｐ＞０．０５）,只有ＰＣＮＡ阳性表达与淋巴结转移有关,在有淋巴结转移和无淋巴结转移的非小细胞肺癌的患者中,ＰＣＮＡ表达的阳性率分别为２５％和９％,淋巴结转移患者的ＰＣＮＡ表达阳性率明显高于无淋巴结转移者（Ｐ＜０．０５）。ｐ５３、ＣＥＡ的表达与生存期有关,生存６个月以下和１２个月的患者的ｐ５３表达阳性率分别为５０％,２０％（Ｐ＜０．０５）,ＣＥＡ的阳性率分别为６０％,４０％（Ｐ＜０．０５）,从而提示ｐ５３和ＣＥＡ表达阳性率越高,患者生存期越短,预后差。     

p53 gene mutations in primary lung tumors are conserved in brain metastases

The p53 product is frequently mutated in human tumors. Both acquired and inherited mutations have been described. These mutations transform p53 from a growth suppressor gene to a transforming oncogene. We examined tissue from 6 patients with primary lung carcinoma and the corresponding brain metastases for the presence of p53 mutations by immunohistochemistry. We then confirmed and characterized the mutations by single strand conformation analysis and by direct sequence analysis. All 6 patients had primary and metastatic tumor expressing a mutant p53. The mutations were all G-T transversions and mapped to exons 5, 6, 7, and 8. The mutations in the primary tumors were precisely conserved in the brain metastases.     

端粒酶逆转录酶、P53、PCNA在非小细胞肺癌的表达及意义

目的　探讨端粒酶逆转录酶、P5 3、PCNA在非小细胞肺癌组织及癌旁正常组织中的表达及其关系。方法　取自手术切除及肺穿刺经病理证实为肺癌组织标本 6 0例 ,采用免疫组化法检测人端粒酶逆录酶、P5 3、PCNA的表达 ,并取癌旁肺组织 10例作对照。结果　肺癌组织中端粒酶逆转录酶、P5 3、阳性率分别为78 3% ( 4 7/6 0 )和 5 3 3% ( 32 /6 0 ) ,PCNA的指数为 5 8 6 3± 10 6 1。癌旁组织依次为 0 % ( 0 /10 ) ,10 % ( 1/10 )和30 3± 7 3,(P <0 0 1) ;在鳞癌中的表达依次为 72 7% ,5 1 5 % ,5 7 78± 10 6 8;在腺癌中的表达依次为88 2 % ,5 2 9% ,5 9 18± 11 4 7;在腺鳞癌中依次为 80 % ,6 0 % ,6 1 2± 10 6 7,(P >0 0 5 )。临床分期的关系为 :Ⅰ期依次为 71% ,35 5 % ,5 5 74± 10 71;Ⅱ期为 87 5 % ,70 8% ,5 9 79± 9 14 ;Ⅲ期为 80 4 % ,80 1% ,71 6±7 31 (P <0 0 1)。在淋巴结转移阳性病例中表达为 89 7% ,6 0 9% ,6 1 72± 9 74 ;在淋巴结转移阴性病例中为 6 7 7% ,38 7% ,5 5 74± 10 71,(P =0 0 2 8) ;病理分化较高组织中的表达为 70 4 % ,2 9 6 % ,5 5 6 3± 9 72 ,分化中等的为 84 2 % ,6 8 4 % ,5 8 2 6± 10 2 6 ,分化较低的组织中为 85 7% ,78 6 % ,6 4 93± 10 7     

直肠癌p53、K-ras基因突变与临床病理的相关性研究

目的　探索p5 3、k ras基因同时突变对直肠癌的恶性行为升级的作用及其临床意义。方法　用PCR SSCP方法检测直肠癌细胞p5 3、K ras基因突变 ,分析该基因突变与临床病理因素及预后的关系。结果　直肠癌细胞p5 3、K ras基因突变与临床病理因素无关 ,生存率也无统计学差异。结论　直肠癌细胞p5 3、K ras基因突变对癌细胞恶性生物学行为升级无明显的促进作用 ,p5 3、K ras基因同时突变也无协同促癌作用 ,也不影响病人的预后。     

乳腺癌患者外周血DNA p53基因突变的检测及其与预后关系的研究

目的 探讨乳腺癌患者外周血中DNAp53基因突变与预后的关系。方法 对126例乳腺癌患者和92例正常对照者血浆DNA含量进行检测。外周血浆中DNA由Qiagen纯化柱纯化,组织标本DNA抽提方法参照非有机化方法。应用PCR—SSCP方法检测DNA中p53基因5,6,7,8外显子点突变。结果 健康妇女外周血中DNA的平均值为21ng/ml,而乳腺癌患者为211ng/ml(P＜0．01)。126例乳腺癌患者中有46例(35.6％)原发瘤中检出p53突变,其中30例(65．2％)患者外周血DNA中检出p53基因突变。乳腺癌患者外周血中DNA p53基因突变与临床分期、肿瘤大小、淋巴结转移情况和雌激素受体状况密切相关(P＜0．05)。肿瘤原发灶与外周血中均检出DNA p53基因突变者预后较差,22例发生复发或转移的患者中,有13例(59．0％)外周血中检出DNA p53基因突变。结论 乳腺癌患者外周血中DNA p53基因的突变,可作为一种预后指标和提示肿瘤早期复发和远处转移的预后因子。     

The relation of p53 gene mutations to gastric cancer subsite and phenotype

Objectives: We investigated p53 gene mutations in advanced gastric cancers by direct DNA sequencing, in order to determine the frequency of mutations in gastric cancers having different epidemiological backgrounds, tumors of the cardia were compared with those arising in the antrum or corpus. Intestinal type cancers were compared with diffuse or other histologic types. We have chosen to assess the frequency of mutations solely based on DNA sequencing.Methods: Paraffin embedded tissues from 100 gastric cancers were evaluated. The mutational status of the p53 gene in exons 5 through 9 were determined by direct sequencing of PCR products.Results: Mutations in exons 5, 6, 7 and 8 were found in 35 of 100 (35%) stomach cancers. One tumor had mutations in both exons 5 and 8. No mutations were detected in exon 9. p53 gene mutations were significantly more frequent in cancers of the cardia (19/35; 54%) than the antrum and corpus (16/65 (25%)) (p 0.005). p53 mutations were more frequent in intestinal type cancers (28/67; 42%) than diffuse cancers or other histologic types of cancer (7/33; 21%), but the difference was not statistically significant.Conclusions: Cancers of the cardia more frequently contain p53 mutations than do antral and corpus cancers, suggesting that cancers in the proximal and distal stomach evolve through different molecular pathways.     

p53 Cooperates berberine-induced growth inhibition and apoptosis of non-small cell human lung cancer cells in vitro and tumor xenograft growth in vivo

Berberine has been shown to have anti-carcinogenic effects. Since p53 is the most commonly mutated tumor suppressor gene, and a lack of functional p53 is associated with an increased risk of cancer development, we examined the effects of berberine on p53-positive and p53-deficient non-small cell human lung cancer cells in vitro and in vivo. Treatment of A549, which express wild-type p53, and H1299, which are p53-deficient, human lung cancer cells with berberine resulted in inhibition of cell proliferation and an increase in apoptotic cell death; however, A549 cells were more sensitive to the berberine-induced cytotoxic effects than H1299 cells. Further, the treatment of A549 cells with pifithrin-alpha, a specific inhibitor of p53, or transfection of A549 cells with a p53 antisense oligodeoxynucleotide resulted in a reduction in the berberine-induced inhibition of cell proliferation and apoptosis. The berberine-induced apoptosis of both the A549 and H1299 human lung cancer cells was associated with the disruption of mitochondrial membrane potential, reduction in the levels of Bcl-2, Bcl-xl while increase in Bax, Bak, and activation of caspase-3. Treatment of the cells with pan-caspase inhibitor (z-VAD-fmk) or caspase-3 inhibitor (z-DEVD-fmk) inhibited berberine-induced apoptosis, thus suggesting the role of caspase-3. Further, the administration of berberine by oral gavage inhibited the growth of s.c. A549 and H1299 lung tumor xenografts in athymic nude mice, however, the growth of tumor xenograft of H1299 cells was faster than A549 cells in mice and the chemotherapeutic effect of berberine was more pronounced in the p53-positive-A549 tumor xenograft than p53-deficient-H1299 tumor xenograft.     

Prognostic value of p53 molecular status in high-risk primary breast cancer.

BACKGROUND: Mutations in the p53 gene are the most common genetic alterations in human primary breast carcinoma and these mutations are often associated with worse prognosis and chemo/radioresistance. PATIENTS AND METHODS: The analysis of the p53 gene was performed by fluorescence-assisted mismatch analysis in 13 consecutive high-risk primary breast cancer (HR-BC) patients with 10 or more involved axillary nodes to evaluate its prognostic value. RESULTS: Three p53 mutations (23%) and four allelic variants were detected. After a median follow-up of 52 months the HR-BC disease-free survival (DFS) was 51% and overall survival 79%. All patients harboring a p53 mutation (p53(mut)) relapsed within 10 months of the median DFS while 67% of those showing a wild-type p53 status (p53(wt)) survive disease-free at a median follow-up of 43 months. One p53(mut) patient is still alive while all the p53(wt) patients survive at 56 months median follow-up. Two out of the four p53(wt) relapsing breast cancer patients showed the Arg72Pro allelic variant; one of these died at 75 months. CONCLUSIONS: p53 mutations may help identify a subset of very high risk breast cancer patients (vHR-BC) with worse prognosis.     

非小细胞肺癌p53、FHIT、K-RAS基因突变与吸烟相关性Meta分析

目的：从循证医学的角度对非小细胞肺癌患者p53、FHIT、K-RAS基因突变异常表达与吸烟相关性进行Meta分析。方法：检索中国学术期刊网全文数据库（CNKI）、中国科技期刊数据库（维普资讯网）、美国国立图书馆PubMed数据库,美国临床肿瘤学会（ASCO）论文集,辅以手工检索;检索时间段为1990年-2010年。检索出p53、FHIT、K-RAS基因突变与吸烟关系研究的文献197篇,最终符合纳入标准的文献26篇。对纳入文献进行方法学质量评价,采用Meta分析专用软件Review Manager 5.0进行统计分析。结果：共纳入26个研究,分别对有相同统计内容且可以合并统计的p53、FHIT、K-RAS基因突变与吸烟关系合并OR值并计算95%CI。分别为：吸烟人群p53基因突变率较高,表现为低表达,[OR=3.50,95%CI（2.45-5.00）,总体效应检验Z=6.88,P〈0.0001];吸烟人群K-RAS基因突变率明显偏高,表现为高表达,[OR=4.50,95%CI（3.00-6.75）,总体效应检验Z=7.26,P〈0.0001];吸烟人群FHIT基因突变率较高,表现为低表达,[OR=2.99,95%CI（1.01-8.88）,总体效应检验Z=1.98,P=0.005]。结论：吸烟与p53、FHIT、K-RAS基因突变率呈正相关,其中p53、FHIT基因高表达为保护性因素,K-RAS基因高表达为危险因素。     

Circulating free DNA,p53 antibody and mutations of KRAS gene in endometrial cancer

This study was conducted to evaluate the significance of circulating free DNA (CFDNA), p53 antibody (p53‐Ab) and mutations of KRAS gene in the development of endometrial cancer (EC). A total of 109 patients with EC (87 patients with Type I and 22 patients with Type II) took part in this study. KRAS mutations and CFDNA were detected by means of the PCR‐RFLP and enriched by the PCR‐RFPL method. ELISA was used to analyze plasma p53‐Ab. Tissue expression of P53 protein was evaluated immunohistochemically (IHC). The frequency of KRAS mutations was especially high in Grade 2 of Type I EC. CFDNA was frequently detected in patients with early stage of Type II EC at a low level of grade. It is noteworthy that the p53‐Ab positive rate increased in the higher grade of Type I tumors. A significant difference in the number of cases with the p53‐Ab was found in the advanced stage of Type I tumors. The frequency of KRAS and p53‐Ab correlates with tumor stage only in the Type I EC. Plasma CFDNA and p53‐Ab offer a chance to develop a procedure for EC Type II diagnosis. The association between tumor cells related to CFDNA and p53‐Ab with Type II tumor suggests that it might potentially serve as a marker in predicting the prognosis and offers a possibility to individualize treatment regimen.     

端粒酶与p53、p16基因在非小细胞肺癌中的表达及其意义

目的研究端粒酶与p53、p16基因在非小细胞肺癌(NSCLC)中的表达及其意义.方法应用SP法免疫组化技术和TRAP法分别检测40例肺癌组织中端粒酶和p53、p16基因的表达.结果端粒酶及p53、p16基因在NSCLC中的阳性率分别为92.5%、37.5%和66.7%;p53基因阳性表达率与NSCLC及病理分期显著相关(P＜0.05).p16基因阳性表达率与性别、年龄、病理分期、吸烟史、组织学类型和分化程度无显著相关(P＞0.05).端粒酶活性与年龄呈负相关,并与p53基因表达情况和病理分期有关(P＜0.05).结论端粒酶和p53基因的表达与NSCLC的病期进展有关.     

非小细胞肺癌p53、FHIT、K-RAS基因突变与吸烟相关性Meta分析

目的:从循证医学的角度对非小细胞肺癌患者p53、FHIT、K-RAS基因突变异常表达与吸烟相关性进行Meta分析。方法:检索中国学术期刊网全文数据库(CNKI)、中国科技期刊数据库(维普资讯网)、美国国立图书馆PubMed数据库,美国临床肿瘤学会(ASCO)论文集,辅以手工检索;检索时间段为1990年-2010年。检索出p53、FHIT、K-RAS基因突变与吸烟关系研究的文献197篇,最终符合纳入标准的文献26篇。对纳入文献进行方法学质量评价,采用Meta分析专用软件Review Manager 5.0进行统计分析。结果:共纳入26个研究,分别对有相同统计内容且可以合并统计的p53、FHIT、K-RAS基因突变与吸烟关系合并OR值并计算95%CI。分别为:吸烟人群p53基因突变率较高,表现为低表达,[OR=3.50,95%CI(2.45-5.00),总体效应检验Z=6.88,P<0.0001];吸烟人群K-RAS基因突变率明显偏高,表现为高表达,[OR=4.50,95%CI(3.00-6.75),总体效应检验Z=7.26,P<0.0001];吸烟人群FHIT基因突变率较高,表现为低表达,[OR=2.99,95%CI(1.01-8.88),总体效应检验Z=1.98,P=0.005]。结论:吸烟与p53、FHIT、K-RAS基因突变率呈正相关,其中p53、FHIT基因高表达为保护性因素,K-RAS基因高表达为危险因素。