原发性肝癌患者血清p16和DAPK基因启动子甲基化的研究

 目的研究原发性肝癌患者血清p16和DAPK基因启动子甲基化的改变状况及其临床意义。方法运用甲基化特异性PCR技术,检测64例PLC患者血清p16基因和DAPK基因启动子甲基化,并分析与临床病理资料的关系。结果PLC患者血清p16基因和DAPK基因甲基化检出率分别为76.6%(49/64)和40.6%(26/64),而正常对照组和良性肝部疾病组血清未检出p16基因和DAPK基因甲基化;p16基因和DAPK基因甲基化检出率与HBsAg、分期及转移状态无明显关系,而与AFP有关联。结论p16基因和DAPK基因启动子异常甲基化参与了PLC的发生发展过程,并可作为PLC早期辅助诊断的分子标志物之一。     

NSCLC患者血清RASSF2基因甲基化检测临床意义分析

目的:探讨非小细胞肺癌(NSCLC)患者血清中RASSF2基因启动子区域甲基化状况及其临床意义.方法:甲基化特异性聚合酶链反应(MSP)法检测62例NSCLC和30例肺部良性疾病患者及16名健康体检者血清中RASSF2启动子区域甲基化状况,并分析其与临床特征的关系.结果:RASSF2甲基化检出率在NSCLC患者中为38.71％(24/62),而肺部良性疾病患者和健康体检者血清未检出,x2=22.89,P＜0.01.NSCLC患者血清RASSF2基因甲基化检出率与年龄、性别、病理类型、临床分期和分化程度无明显相关(P＞0.05),不吸烟者RASSF2甲基化率高于吸烟者(61.90％ vs 26.83％,x2=7.20,P＜0.05).结论:RASSF2甲基化可能在NSCLC发生、发展中起重要作用,有望成为NSCLC辅助诊断的分子标记.     

NSCLC患者血浆p16和MGMT基因甲基化检测及临床意义

目的：检测非小细胞肺癌（non—small cell lung cancer，NSCLC）患者外周血血浆中p16基因、O^6-甲基乌嘌呤-DNA甲基转移酶（O^6-methylguanine—DNA methyhransferase，MGMT）基因启动子的甲基化状态，探讨p16、MGMT基因启动子的异常甲基化在NSCLC筛查及早期诊断中的意义。方法：利用巢式甲基化特异性聚合酶链反应法检测NSCLC患者外周血血浆p16、MGMT基因启动子的甲基化状态。结果：65例NSCLC血浆样品中分别发现19例（29．23％）p16基因启动子异常甲基化和16例（24．62％）MGMT基因启动子异常甲基化，45例正常对照血浆组未检测到p16、MGMT基因启动子的异常甲基化（P〈0．05），血浆中两基因甲基化检出率与NSCLC的分型及临床分期无明显相关性（P〉0．05）。结论：利用巢式甲基化特异性PCR法检测外周血血浆中p16、MGMT基因启动子的甲基化，可为NSCLC的筛查、早期诊断及预后判断提供有价值的信息。     

非小细胞肺癌患者血清Ras相关区域家族1A基因启动子异常甲基化检测及其临床意义

目的 研究非小细胞肺癌(NSCLC)患者血清Ras相关区域家族1A(RASSF1A)基因启动子区域的甲基化状态及其临床意义.方法 采用甲基化特异性聚合酶链反应(MSP)技术,检测75例NSCLC患者血清RASSF1A基因启动子区域的甲基化状态,并分析其与临床病理参数之间的相关性.结果75例NSCLC患者血清RASSF1A基因启动子区域异常甲基化检出率为30.7%(23/75),而35例肺部良性疾病患者和15例健康志愿者中检出率均为0,差异有统计学意义(P＜0.001).RASSF1A启动子异常甲基化与NSCLC患者的年龄、性别、病理类型无显著相关性,但在晚期及肿瘤分化程度较低的患者中检出率较高(P＜0.05).结论 RASSF1A启动子异常甲基化在NSCLC的发生、发展中起重要作用,有望成为NSCLC辅助诊断和预后判断的分子标记.     

大肠癌组织中unc5c基因启动子甲基化的分析

目的分析大肠癌(colorectal cancer,CRC)组织中unc5c基因启动子区域甲基化的改变状况及其临床意义。方法运用甲基化特异性PCR技术,检测73例大肠癌患者手术切除的癌组织和相应的癌旁组织及28例正常组织、36例腺瘤患者手术切除的腺瘤组织中unc5c基因启动子区域甲基化的改变情况,并分析与临床病理特征之间的关系。结果73例癌组织样本中甲基化检出率为75％(55/73),相应的癌旁组织为7％(5/73),腺瘤组织为63％(23/36),而正常组织中未检出unc5c基因甲基化。unc5c基因甲基化检出率与年龄、分化程度及TNM分期有关。结论检测unc5c基因启动子区域异常甲基化是大肠癌早期辅助诊断的分子标志物之一。     

胃癌中E-cadherin和DAPK基因启动子异常甲基化的研究

目的:检测胃癌中死亡相关蛋白激酶(death-associated protein kinase,DAPK)基因和上皮钙粘蛋白(epithelial cadherin,E-cadherin)基因启动子区CpG岛甲基化状态,并探讨两个基因甲基化改变的特点及其与临床病理特征、患者一般资料之间的关系.方法:采用目前常用的甲基化特异性PCR(Methylation-specific PCR.MSP)方法检测4l例胃癌组织和20例正常对照组织中DAPK、E-cadherin基因启动子区甲基化状态并进行统计分析.结果:41例胃癌组织中DAPK、E-cadherin基因启动子区甲基化阳性率分别为68.3%(28/41)和46.3%(19/41),20例正常时照组织中未检测到DAPK、E-cadherin基因启动子区发生甲基化,两个基因在胃癌组织中的甲基化率明显高于正常对照组织(P<0.05),但DAPK和E-cadherin基因启动子甲基化在胃癌的发生中无协同性(相关性和一致性).胃癌组织中一个基因发生甲基化的检出率为78.0%(32/41);胃癌组织中DAPK基因启动子区甲基化与淋巴结转移、分化程度相关(P<0.05),而E-cadherin基因启动子区甲基化则与淋巴结转移和浸润深度有相关性(P<0.05).两个基因启动子区异常甲基化与被检查者肿瘤的大小、肿瘤的部位等临床病理特征以及被检者的性别、年龄不具有相关性.结论:DAPK、E-eadherin基因启动子区甲基化是胃癌发生、发展过程中的频发事件,通过检测胃粘膜组织中两个基因启动子区甲基化状况,可能会对胃癌的早期诊断及判断预后提供一定的参考价值;联合检测两个基因甲基化状态优于各单个基因检测.     

宫颈癌中p16基因启动子异常甲基化的检测

目的:探讨宫颈癌组织及外周血浆中p16基因启动子异常甲基化的状况及其在宫颈癌诊断中的价值.方法:用甲基化特异性PCR技术对宫颈癌组织,正常宫颈组织及相对应血浆中p16基因进行甲基化的检测.结果:45例宫颈癌组织中p16基因异常甲基化率为33.3％(15/45),相对应血浆中p16基因甲基化的检出率为20％(9/45),而正常对照组织未检出甲基化.血浆中甲基化的改变与宫颈癌组织甲基化状态显著相关(P＜0.05).p16基因甲基化发生率与年龄、病理分级、临床分期之间无统计学相关性(P＞0.05).结论:p16基因CpG岛甲基化是宫颈癌发生的高频事件,其甲基化检测在宫颈癌早期诊断中有一定的应用价值.     

肺癌患者外周血血浆中p16基因异常甲基化的检测

目的 分析肺癌患者外周血血浆中p16基因启动子区异常甲基化发生情况,探讨血浆中p16基因异常改变作为肺癌临床辅助诊断分子生物学标志物的可能性。方法 利用半巢式甲基化特异性PCR技术,检测了137例肺癌患者血浆和112例相对应肿瘤组织DNA p16基因的异常甲基化情况。结果 在血浆和肿瘤组织中的p16基因甲基化检出率分别为75．2％和80．4％;其中鳞癌、腺癌、腺鳞癌和小细胞肺癌患者血浆标本的阳性率分别为77．9％,65．1％,75．1％和91．7％。血浆DNAp16基因甲基化仅在肿瘤组织存在同样甲基化的病例中被检出。血浆和肿瘤组织中,p16基因的甲基化异常改变与肿瘤的分期、分型无明显相关性。结论 分析血浆DNA的p16基因异常甲基化有可能成为辅助肺癌诊断的有效方法之一。     

NSCLC患者血清中p16、DAP基因甲基化的研究

目的：探讨p16、死亡相关蛋白激酶（death-associated protein kinase,DAP）基因的异常甲基化作为非小细胞肺癌（NSCLC）患者诊断的基因标志物的可行性。方法：采用甲基化特异性PCR（MSP）法检测30例NSCLC患者肿瘤组织及对应血清中p16、DAP基因的异常甲基化，结果：NCSLC肿瘤中60．0％（18／30）检测出至少一个基因启动子呈甲基化改变，在18例肿瘤组织检测到异常甲基化的患者中，50．0％的患者（9／18）在血清中检测到相应的改变。所有的癌旁组织、健康对照组的血清中及正常肺组织均未检测到p16、DAP的甲基化，结论：检测NSCLC患者血清中p16、DAP基因异常甲基化有可能成为肺癌诊断的分了标志物。     

中国非小细胞肺癌患者血清DAPK基因、p16基因启动子甲基化的分析

Objective： To evaluate the clinical significance of the aberrant methylation of DAPK gene and p16 gene in sera from 65 NSCLC patients from Nanjing General Hospital of Nanjing Command, China. Methods： A methylation-specific PCR （MSP） was performed for the detection of promoter hypermethylation of DAPK gene and p16 gene in blood DNA from 65 cases of NSCLC, and to analyze the relation of the aberrant methylation of DAPK gene and p16 gene and the clinicopathological data. Results： 30.8% （20/65） of the sera from 65 cases of NSCLC showed hypermethylation for DAPK promoter and 43.1% （28/65） the same for p16 promoter, whereas no methylated DAPK gene promoter and p16 gene promoter were found in sera from the patients with lung benign diseases and normal controls. Methylated DAPK gene promoter and p16 gene promoter in sera were not closely correlated with the pathological classification, stage, metastasis and differentiation in NSCLC. Conclusion： Detection of the aberrant methylation of DAPK gene and p16 gene in blood DNA from NSCLC patients might offer an effective means for the earlier auxiliary diagnosis of the malignancy.     

PROMOTER HYPERMETHYLATION OF p16 GENE AND DAPK GENE IN SERA FROM HEPATOCELLULAR CARCINOMA （HCC） PATIENTS

Objective： To analyze the aberrant methylation of p16 gene and DAPK gene in sera from primary liver cancer patients ad to evaluate the clinical significance. Methods： A methylation-specific PCR was performed for the detection of promoter hypermethylation of p16 gene and DAPK gene in blood DNA from 64 cases of HCC patients, and to analyze the relation of the aberrant methylation of p16 gene and KAPK gene and the clinical pathological data. Results： 76.6%（49/64） of the sera from 64 cases of HCC patients showed hypermethylation for p16 promoter and 40.6% （26/64） for KAPK promoter, whereas no methylated p16 gene promoter and DAPK gene promoter were found in sera from benign liver diseases patients and normal control. Methylated p16 gene and KAPK gene promoters in sera did not strongly correlated with HBsAg, stage, metastasis and differentiation in HCC; but strongly correlated with AFP. Conclusion： Detection of the aberrant methylation of p16 gene and KAPK gene in blood DNA from HCC patients might offer an effective means for the earlier auxiliary diagnosis of the malignancy.     

Aberrant Promoter Methylation Profile in Pleural Fluid DNA and Clinicopathological Factors in Patients with Non-small Cell Lung Cancer

The aim of this study was to investigate the prognostic value of hypermethylation of tumor suppressor genesin patients with non-small cell lung cancer (NSCLC). In samples from 34 lung patients with malignant pleuraleffusions, we used a methylation-specific polymerase chain reaction to detect aberrant hypermethylation of thepromoters of the DNA repair gene O6-methylguanine-DNA methyltransferase (MGMT), p16INK4a, rasassociation domain family 1A (RASSF1A), apoptosis-related genes, death-associated protein kinase (DAPK),and retinoic acid receptor ß (RARß).There is no association between methylation status of five tumor suppressorgenes including MGMT, p16INK4a, RASSF1A, DAPK and RARß in pleural fluid DNA and clinicopathologicalparameters including clinical outcome. Aberrant promoter methylation of tumor suppressor genes in pleuralfluid DNA could not be a valuable prognostic marker of NSCLC patients with malignant pleural effusion.     

非小细胞肺癌pl6/CDKN2基因失活的研究

目的：分析中国人非小细胞肺癌中ｐ１６／ＣＤＫＮ２基因失活的情况,探讨该基因在肺癌发生中的作用。方法：选取与ｐ１６基因紧密连锁的Ｄ９Ｓ１７４８位点,对１７例临床切除的原发性肺癌标本进行微卫星不稳定性分析,用甲基化特异性ＰＣＲ（ｍｅｔｈｙｌａｔｉｏｎ－ｓｐｅｃｉｆｉｃ ＰＣＲ, ＭＳＰ）检测 ｐｌ６基因启动子区 ＣｐＧ岛甲基化状况,用免疫组织化学法检测Ｐ１６蛋白表达情况。结果：微卫星不稳定性分析结果表明,在１３例Ｄ９Ｓ１７４８位点存在多态性的肿瘤ＤＮＡ中有 ９例（６９ ．２％）发生了杂合性缺失（ｌｏｓｓ ｏｆ ｈｅｔｅｒｏｚｙｇｏｓｉｔｙ, ＬＯＨ）。 ＭＳＰ的结果显示,有 ７０． ６％（１２／１７）的肿瘤组织存在ｐ１６启动子区的异常高甲基化。在本研究中,８２．４％（１４／１７）的肿瘤组织可以检测出一种或两种ｐ１６基因的异常改变。对此１７例肿瘤标本进行的免疫组织化学分析显示,有 １３例 Ｐ１６蛋白表达阴性,其中 ９２ ３％（１２／１３）存在一种或两种ｐ１６基因的异常改变。免疫组化结果与ｐ１６基因分子遗传学改变情况基本吻合。结论：作为一种抑癌基因,ｐ１６在多种肿瘤组织中都有异常改变。我们的研究表明,ｐ１６基因失表达是非小细胞肺癌     

肺癌血清p16基因启动子畸变甲基化检测

[目的]检测肺癌患者血清DNA中p16基因启动子畸变甲基化,并探讨其在肺癌早期诊断和预后评价中的作用。[方法]收集新鲜的肺癌组织及其对应的血清标本69例,肺良性疾病患者标本25例,健康人血清标本10例。采用PCR技术分别检测肿瘤组织DNA和血清游离DNA中p16基因启动子畸变甲基化的状况。[结果]28.99%(20/69)肺癌组织出现p16高甲基化;出现高甲基化的组织标本相对应的20例血清中有15例(75%)出现p16基因高甲基化。肺良性疾病患者及正常人的血清、DNA中均未见p16基因高甲基化。血清p16基因高甲基化与肺癌TNM分期及分化程度密切相关(P<0.01或P<0.05)。[结论]非小细胞肺癌血清中p16基因甲基化状况的检测,可能有助于非小细胞肺癌的早期诊断或预后评估。     

Aberrant promoter methylation in pleural fluid DNA for diagnosis of malignant pleural effusion

Accumulating evidence implicates epigenetic changes such as hypermethylation in carcinogenesis. We investigated whether DNA methylation of 5 tumor suppressor genes in pleural fluid samples could aid in diagnosis of malignant effusion. In samples from 47 patients with malignant pleural effusions and 34 with nonmalignant effusions, we used a methylation-specific polymerase chain reaction to detect aberrant hypermethylation of the promoters of the DNA repair gene O(6)-methylguanine-DNA methyltransferase (MGMT), p16(INK4a), ras association domain family 1A (RASSF1A), apoptosis-related genes, death-associated protein kinase (DAPK), and retinoic acid receptor beta (RARbeta). Promoter hypermethylation was associated with malignant effusion for MGMT (Odds ratio (OR) = infinity), p16(INK4a) (OR = infinity), RASSF1A (OR = 13.8; CI, 1.71-112), and RARbeta (OR = 3.17; CI, 1.10-9.11), but not for DAPK. Instead, DAPK methylation was associated with the length of smoking (p < 0.05). Patients with hypermethylation of MGMT, p16(INK4a), RASSF1A or RARbeta were 5.68 times more likely to have malignant effusions than patients without methylation (p = 0.008). Methylations per patient were more numerous for lung cancer than nonmalignant pulmonary disease (0.915 vs. 0.206, p < 0.001). Sensitivity, specificity, and positive predictive value of methylation in one or more genes for diagnosis of malignant effusion were 59.6%, 79.4%, and 80.0% respectively. In conclusion, aberrant promoter methylation of tumor suppressor genes in pleural fluid DNA could be a valuable diagnostic marker for malignant pleural effusion.     

Development and application of a multiplex PCR procedure for the detection of DNA methylation in colorectal cancer

Cancers often exhibit aberrant methylation of gene promoter regions associated with loss of tumor suppressor and/or DNA repair gene function. Such methylation constitutes an excellent marker for the molecular detection of micro-metastases and the diagnosis of tumor recurrences. We have developed a multiplex methylation-specific PCR (MSP) procedure for rapid and simultaneous assessment of the methylation of 5 loci: the tumor suppressor genes p16INK4a, death-associated protein kinase (DAPK) and p14ARF, and the DNA repair genes hMLH1 and O6-methylguanine-DNA-methyltransferase (MGMT). This multiplex test uses one single PCR reaction and only one electrophoretic run. In 98 samples of colorectal cancer studied, methylation of MGMT, DAPK, p16, hMLH1 and p14 was present in 31, 20, 17, 16 and 14% of tumors, respectively. In 58% of the tumors at least one methylated gene was found. This multiplex MSP constitutes a simple and inexpensive method for screening of molecular signatures in colorectal cancer and can be used profitably before employing more expensive and complex techniques such as microarray testing.     

鼻咽癌组织中DAPK基因启动子甲基化的研究

目的:分析鼻咽癌组织中DAPK基因启动子的甲基化状态,探讨DAPK基因启动子甲基化与鼻咽癌的关系。方法:应用甲基化特异性PCR技术检测48例鼻咽癌组织、26例慢性鼻咽黏膜炎症组织的DAPK基因启动子甲基化状态,比较鼻咽癌和慢性鼻咽黏膜炎症组织的DAPK基因启动子甲基化率。结果:鼻咽癌组织的DAPK基因启动子甲基化率为75%,而慢性鼻咽黏膜炎症组织中未检测到DAPK基因启动子甲基化。结论:鼻咽癌组织中DAPK基因启动子存在高甲基化水平,检测DAPK基因启动子甲基化或许能为鼻咽癌的诊断提供依据。