结直肠癌患者SorCS1基因启动子甲基化检测的临床价值

目的 探讨结直肠癌患者SorCS1基因启动子甲基化检测的临床价值。方法 收集17例结直肠癌患者的癌组织和癌旁组织,采用MassARRAY平台检测结直肠癌患者癌组织与癌旁组织相关基因启动子甲基化水平,筛选出癌组织与癌旁组织基因启动子甲基化存在差异的基因,并与肿瘤基因图谱计划（TCGA）数据库进行比对。同时检测SEPT9基因甲基化水平。用癌组织基因启动子甲基化检测值与癌旁组织基因启动子甲基化检测值的差值（Δ）表示结直肠癌患者癌组织基因启动子甲基化水平相对于癌旁组织的差异。结果 共筛选出2个基因（SorCS1、CASR）。结直肠癌患者癌组织SorCS1、CASR、SEPT9基因启动子甲基化水平均显著高于癌旁组织（P<0.001）。与TCGA数据库的比对结果显示,膀胱尿路上皮癌、宫颈鳞状细胞癌、结肠腺癌、多形性胶质母细胞瘤、直肠腺癌、胃腺癌患者的SorCS1基因相对表达量均低于正常对照者（P<0.05）,结肠癌、直肠癌、肺腺癌患者SorCS1基因启动子甲基化水平明显高于正常对照者（P<0.05）;结直肠癌患者与正常对照者之间CASR基因相对表达量差异无统计学意义（P>0...     

粪便SDC2基因甲基化检测联合结肠镜在早期结直肠癌筛查中的意义

目的探讨粪便SDC2基因甲基化检测联合结肠镜在早期结直肠癌(CRC)筛查中的意义。方法选择2018年1月-2019年10月在深圳市宝安区中心医院体检的1 000例体检者作为研究对象,使用试剂盒分别检测粪便SDC2基因甲基化和血浆SEPT9基因甲基化,对两者任一结果为阳性者再行结肠镜检查。比较SDC2和SEPT9基因甲基化检测的阳性率以及两者联合结肠镜对进展性腺瘤和CRC的检出率。结果在1 000例筛查对象中,粪便SDC2基因甲基化检测阳性率明显高于血浆SEPT9基因甲基化〔18.10%(181/1 000)比9.80%(98/1 000)〕,差异有统计学意义(P<0.05);粪便SDC2基因甲基化检测联合结肠镜对进展性腺瘤和CRC的检出率均明显高于血浆SEPT9基因甲基化检测联合结肠镜筛查〔进展性腺瘤检出率:2.50%(25/1 000)比1.00%(10/1 000),CRC检出率:1.50%(15/1 000)比0.50%(5/1 000)〕,差异均有统计学意义(均P<0.05)。结论粪便SDC2基因甲基化检测是一种简单无创的CRC筛查新技术,患者接受程度更高,能够避免大规模肠镜筛查带来的弊端,联合结肠镜检测可作为CRC早期筛查的首选策略。     

外周血SEPT9基因甲基化检测在结直肠癌中的研究进展

外周血SEPT9基因甲基化检测在结直肠癌(CRC)诊断和筛查中敏感性及特异性较高,目前有关外周血SEPT9基因甲基化检测的四种算法中,Septin9(1/3)算法灵敏性最高,Septin9(2/3)算法特异性最高.可根据研究的目的进行外周血SEPT9基因甲基化检测的算法选择,满足实际检测需求.SEPT9基因甲基化检测在...     

血清SEPT9基因甲基化检测在结直肠癌诊断中的应用

目的探讨血清代替血浆检测SEPT9基因甲基化在结直肠癌(CRC)诊断中的价值。方法收集70例CRC患者、38例腺瘤或息肉患者及15例其他肠道疾病患者血清样本。用Epi pro Colon 2.0试剂盒进行SEPT9基因甲基化检测,依据肠镜病理诊断进行验证,比较SEPT9、癌胚抗原(CEA)和粪便潜血试验(FOBT)的敏感性和特异性,并进行统计学分析。结果 CRC患者血清SEPT9的阳性率(81.4%)明显高于对照组(13.2%),差异有统计学意义(χ2=92.814,P0.01)。CRC患者血清SEPT9的敏感性为81.4%(95%CI:72.4%~90.4%)、特异性为86.7%(95%CI:72.4%~100%)。临床分期为Ⅰ期的CRC患者SEPT9阳性率为42.9%,Ⅱ期为88.9%,Ⅲ期为82.4%,Ⅳ期为100%,差异有统计学意义(χ2=16.572,P0.01)。SEPT9的ROC曲线下面积(AUCROC)为0.841,明显高于CEA(0.716)和FOBT(0.792)。3者联合检测AUCROC可达0.935。结论血清SEPT9基因甲基化的检测是早期诊断CRC的有效方法,联合检测CEA及FOBT可以提高诊断效能。     

P27基因甲基化与结直肠癌发生发展及临床生物学行为的关系

目的:研究P27基因在结直肠癌发生过程中的蛋白表达和基因启动子区CpG岛甲基化状态的变化及意义.方法:采用免疫组织化学染色和甲基化特异性PCR系统检测结直肠癌患者手术切缘黏膜上皮、癌旁组织、癌组织各56例、腺瘤42例中p27蛋白的表达和基因甲基化状态的变化.结果:p27蛋白在结直肠癌患者手术切缘黏膜上皮的表达率最高(77%),随病变进展其表达率呈下降趋势,其在癌旁组织(59%)、腺瘤(57%)和癌组织(32%)中的表达与手术切缘黏膜上皮相比及癌与癌旁组织或腺瘤相比差异均有统计学意义;在结直肠癌发生过程中,P27基因甲基化程度呈增加趋势,且在各病变阶段与蛋白的表达呈明显负相关,其甲基化程度还与淋巴结转移密切相关.结论:P27基因异常甲基化是p27失活的主要机制,与结直肠癌的发生、发展密切相关,可作为结直肠癌早期诊断、临床生物学行为和预后判断的重要参考指标.     

结直肠癌C-erbB-2基因启动子CpG岛甲基化状态及其与C-erbB-2蛋白表达的关系

目的了解结直肠癌组织C-erbB-2基因启动子区CpG岛甲基化状态、C-erbB-2蛋白表达水平及两者之间的关系。方法取经病理确诊的43例结直肠癌组织和相应癌旁组织,分别用甲基化特异性聚合酶链反应(MSP)和免疫组织化学法(IHC)检测C-erbB-2启动子区CpG岛的甲基化和C-erbB-2蛋白表达水平。结果癌组织和癌旁组织中C-erbB-2启动子区CpG岛甲基化率分别为44.2%和74.4%,差异具有统计学意义(P=0.004)。癌组织和癌旁组织中C-erbB-2蛋白过度表达率分别为67.4%和27.9%,差异具有统计学意义(P=0.000)。C-erbB-2蛋白表达水平与肿瘤分期相关。结直肠癌组织C-erbB-2启动子区CpG岛甲基化状态与C-erbB-2蛋白表达水平呈显著相关(r=0.331,P=0.03)。结论结直肠癌中C-erbB-2基因启动子区CpG岛的低甲基化可能在C-erbB-2蛋白过度表达中起一定作用,有望成为有用的肿瘤分子诊断标记和治疗靶点。     

SEPT9甲基化检测在结直肠癌早期诊断中价值的研究进展

结直肠癌是我国常见恶性消化道肿瘤之一,其发病率逐年上升且预后不好,病死率较高。早发现、早诊断可有效降低结直肠癌致死率。目前,临床用于结直肠癌诊断及监测的肿瘤标志物有癌胚抗原(CEA)、糖类抗原19-9(CA199)、糖类抗原242(CA242)等,这些标志物在结直肠癌早期诊断中的临床价值不够理想。因此,探索新的、早期诊断价值更高的肿瘤标志物用于结直肠癌筛查是当前研究的热点之一。SEPT9是一种抑癌基因,SEPT9基因甲基化检测对结直肠癌早期诊断有较高的特异度和灵敏度,该文就SEPT9基因甲基化检测在结直肠癌早期诊断中的研究进展进行综述。     

肺癌患者癌组织和血浆p16基因甲基化的检测及其临床意义

目的研究非小细胞肺癌患者癌组织和血浆p16基因甲基化及其临床意义。方法选择120例非小细胞肺癌患者,用巢式甲基化特异性聚合酶链反应法检测其肺癌组织、癌旁正常组织和外周血血浆p16基因的甲基化,并对120例正常对照组血浆样品进行p16基因甲基化检测,各组检测结果进行比较。结果肺癌组织p16基因甲基化率44.2%,高于癌旁组织的11.7%(P0.01);非小细胞肺癌患者血浆样品中p16基因甲基化检测率为32.5%,对照组血浆未检测到p16基因甲基化(P0.01);肺癌患者血浆样品与癌组织p16基因甲基化检出率比较差异无显著性(P0.05);患者血浆样品与癌旁组织p16基因甲基化检出率比较差异有显著性(P0.01)。结论肺癌患者癌组织和血浆样本p16基因甲基化的检测都为肺癌的早期筛查和诊断提供了有价值的参考信息。     

甲基化在肺癌中的意义

目的探讨基因T-钙黏蛋白(CDH13)在40例癌组织,40例的癌旁组织标本和非肺癌良性肺切除组织标本15例作为对照的表达的临床意义,进一步研究其基因异常甲基化与肺癌的相关性。方法采用特异性甲基化PCR(MSP)检测该基因在肺癌组织中异常甲基化的水平。结果 1.在肺癌组织中CDH13基因甲基化率明显高于癌旁组织和非肺癌良性肺切除组织,甲基化率分别为32.5%、7.5%、6.7%,有统计学意义(P<0.05)。2.CDH13基因异常甲基化和CDH13的表达水平呈负相关性(r=-0.520).3.CDH13基因启动子区5’CpG岛甲基化阳性率在肺癌组织中显著高于癌旁组织和非肺癌良性肺切除组织,CDH13基因启动子区5’CpG岛甲基化导致了CDH13的表达下调。结论在肺癌组织中CDH13基因异常甲基化率明显升高且有临床诊断意义,CDH13基因在癌组织中的异常甲基化水平将有望成为肺癌新的治疗靶点。     

非小细胞肺癌p16基因甲基化及其临床诊断意义

目的 研究非小细胞肺癌癌组织p16基因甲基化及其临床诊断意义.方法 选择47例非小细胞肺癌患者,用MSP技术检测肺癌组织和癌旁正常组织p16基因甲基化.结果 肺癌组织p16基因甲基化率44.7%,高于癌旁组织的17.0%(P＜0.01);肺癌组织甲基化检出率与临床分期、临床病理分型和临床分类之间差异无统计学意义(均P＞0.05).结论 提示肺癌有关组织或样本的p16基因甲基化,可能成为各种临床类型的非小细胞肺癌早期诊断的一个有效指标.但特异性、灵敏性和可行性等有待进一步研究.     

粪便基因甲基化对结直肠肿瘤诊断价值的Meta分析

目的系统评价粪便基因异常甲基化诊断结直肠肿瘤的准确性。方法计算机检索TheCochraneLibrary、PubMed、EMbase、CBM、WebofScience、CNKI和WanFangData,收集粪便基因甲基化诊断结直肠肿瘤的研究,检索时限为1990年1月至2012年2月,同时依据QUADAS条目评价纳入研究质量,采用Meta—Discl．4软件进行数据分析。结果最终共纳入32个研究,3951例患者。Meta分析结果显示：粪便基因甲基化对于检测结直肠肿瘤的合并敏感度（Sen）、特异度（Spe）、诊断比值比（DOR）、SROC曲线下面积（AUC）及Q木值分别为92％195％CI（91％,93％）]、63％[95％CI（61％,65％）]、20．79[95％CI（15．13,28．57）]、O．8619（SE=0．0204圾0．7926（SE=0．0198）;对于检测结直肠癌的合并Sen、Spe及SROCAUC分别为91呱95％CI（89％,92％）]、75％[95％CI（73％,77％）圾0．9007;而对于结直肠腺瘤的合并Sen、Spe及SROCAUC分别为79％[95％CI（76％,83％）]、7596[95％CI（73％,77％）]及0．8457。结论粪便基因异常甲基化对于诊断结直肠肿瘤具有较高的敏感性（92％）和中度特异性（63％）,可作为诊断结直肠肿瘤的无创性初筛方法。     

Accuracy of early detection of colorectal tumours using stool methylation markers: A meta-analysis

AIM: To evaluate the accuracy of methylation of genes in stool samples for diagnosing colorectal tumours. METHODS: Electronic databases including PubMed, Web of Science, Chinese Journal Full Text Database and Wanfang Journals Full-text Database were searched to find relevant original articles about methylated genes used in diagnosing colorectal tumours. Quality assessment of diagnostic accuracy studies items were used to evaluate the quality of the included articles, and the Meta-disc 1.4 and SPSS 13.0 software programs were used for data analysis. RESULTS: Thirty-four articles met the inclusion criteria, and 4151 patients were included. Pooled diagnostic performances of SFRP2 methylation for colorectal cancer (CRC) provided the following results: the sensitivity was 79% (95%CI: 75%-82%), the specificity was 93% (95%CI: 90%-96%), the diagnostic odds ratio (DOR) was 47.57 (95%CI: 20.08-112.72), and the area under the curve was 0.9565. Additionally, the results of accuracy of SFRP2 methylation for detecting colorectal adenomas were as follows: the sensitivity was 43% (95%CI: 38%-49%), the specificity was 94% (95%CI: 91%-97%), the DOR was 11.06 (95%CI: 5.77-21.18), and the area under the curve was 0.9563. CONCLUSION: Stool-based DNA testing may be useful for non-invasively diagnosing colorectal tumours, and SFRP2 methylation is a promising marker that has great potential in early CRC diagnosis.     

DNA methylation biomarkers for blood-based colorectal cancer screening

BACKGROUND: Sensitive, specific blood-based tests are difficult to develop unless steps are taken to maximize performance characteristics at every stage of marker discovery and development. We describe a sieving strategy for identifying high-performing marker assays that detect colorectal cancer (CRC)-specific methylated DNA in plasma. METHODS: We first used restriction enzyme-based discovery methods to identify marker candidates with obviously different methylation patterns in CRC tissue and nonpathologic tissue. We then used a selection process incorporating microarrays and/or real-time PCR analysis of tissue samples to further test marker candidates for maximum methylation in CRC tissue and minimum amplification in tissues from both healthy individuals and patients with other diseases. Real-time assays of 3 selected markers were validated with plasma samples from 133 CRC patients and 179 healthy control individuals in the same age range. RESULTS: Restriction enzyme-based testing identified 56 candidate markers. This group was reduced to 6 with microarray and real-time PCR testing. Three markers, TMEFF2, NGFR, and SEPT9, were tested with plasma samples. TMEFF2 methylation was detected in 65% [95% confidence interval, 56%-73%] of plasma samples from CRC patients and not detected in 69% (62%-76%) of the controls. The corresponding results for NGFR were 51% (42%-60%) and 84% (77%-89%); for SEPT9, the values were 69% (60%-77%) and 86% (80%-91%). CONCLUSIONS: The stringent criteria applied at all steps of the selection and validation process enabled successful identification and ranking of blood-based marker candidates.     

结直肠癌患者p16基因甲基化的检测

目的检测p16基因启动子区异常甲基化发生情况,探讨p16基因异常甲基化作为结直肠癌临床辅助诊断分子生物学标志物的可能性。方法选取2004年5月至2004年12月第三军医大学西南医院及贵州省人民医院普外科住院的结直肠癌患者53例,所有患者均经病理学诊断证实,并按Dukes病理分期分为四期,提取肿瘤组织DNA,分别应用巢式甲基化特异性PCR(nested methylation specific polymerase chain reaction,nested-MSP)及甲基化特异性PCR(methylation specific polvmerase chain reaction,MSP)方法,检测患者肿瘤组织中p16基冈的异常甲基化情况;比较MSP及nested-MSP两方法的灵敏度。结果应用MSP方法,Dukes A、B期患者和Dukes C、D期患者p16基因的甲基化率分别为23.8%和59.4%,两组比较有显著性差异(P<0.05);应用nested-MSP方法,Dukes A、B期患者和Dukes C、D期患者p16基因的甲基化率分别为52.4%和84.4%,两组比较有显著性差异(P<0.05)。应用MSP与nested-MSP方法检测肿瘤组织p16基因甲基化的阳性率分别为45.3%(24/53)、71.7%(38/53),两组比较有显著性差异(P<0.01)。结论应用nested-MSP方法检测肿瘤组织p16基因甲基化的灵敏度明显高于普通的MSP方法,分析患者DNA的p16基因异常甲基化有可能成为结直肠癌辅助诊断及预后评估的有效方法之一。     

Promoter DNA Methylation of Oncostatin M receptor-β as a Novel Diagnostic and Therapeutic Marker in Colon Cancer

In addition to genetic changes, the occurrence of epigenetic alterations is associated with accumulation of both genetic and epigenetic events that promote the development and progression of human cancer. Previously, we reported a set of candidate genes that comprise part of the emerging “cancer methylome”. In the present study, we first tested 23 candidate genes for promoter methylation in a small number of primary colon tumor tissues and controls. Based on these results, we then examined the methylation frequency of Oncostatin M receptor-β (OSMR) in a larger number of tissue and stool DNA samples collected from colon cancer patients and controls. We found that OSMR was frequently methylated in primary colon cancer tissues (80%, 80/100), but not in normal tissues (4%, 4/100). Methylation of OSMR was also detected in stool DNA from colorectal cancer patients (38%, 26/69) (cut-off in TaqMan-MSP, 4). Detection of other methylated markers in stool DNA improved sensitivity with little effect on specificity. Promoter methylation mediated silencing of OSMR in cell lines, and CRC cells with low OSMR expression were resistant to growth inhibition by Oncostatin M. Our data provide a biologic rationale for silencing of OSMR in colon cancer progression and highlight a new therapeutic target in this disease. Moreover, detection and quantification of OSMR promoter methylation in fecal DNA is a highly specific diagnostic biomarker for CRC.     

腺瘤样结肠息肉易感基因(APC)及结直肠癌缺失基因(DCC)基因甲基化在肺癌早期诊断的意义

目的 探讨腺瘤样结肠息肉易感基因(APC)及结直肠癌缺失基因(DCC)基因甲基化在肺癌早期诊断的意义。方法 对245例肺癌患者、150例非恶性肺病患者和40例健康志愿者抽取晨起空腹外周血,应用甲基化特异性PCR法检测APC和DCC启动子区甲基化状态。并对其与临床病理特征等进行相关性分析。结果 ①肺癌组患者外周血中APC及DCC启动子甲基化阳性率分别为26.53%(65/245)和36.33%(89/245); 非肺癌组患者外周血中APC及DCC启动子甲基化阳性率分别为2.67%(4/150)和8.00%(12/150); 健康志愿者外周血中APC及DCC启动子甲基化阳性率为0; 肺癌组与非肺癌组、健康志愿者组相比,APC和DCC基因甲基化检测结果比较,差异均有统计学意义(P<0.01)。②APC及DCC基因甲基化联合检测,诊断肺癌灵敏度为52.65%,特异度为89.33%,联合检测与单独APC检测相比,敏感度与特异度差异均有统计学意义(P<0.01); 联合检测与单独DCC检测相比,敏感度有统计学差异(P<0.01),但是特异度差异不明显(P>0.05); ③甲基化检测结果与患者性别、年龄、病理类型、病理分化程度、临床TNM分期等没有相关性(P>0.05)。结论 APC和DCC基因甲基化与非小细胞肺癌的发生发展密切相关,可以作为肺癌早期诊断标志物之一。     

The stool DNA test: an emerging technology in colorectal cancer screening.

The stool DNA test is considered an emerging technology in screening for colorectal cancer. The stool DNA test detects DNA markers which are shed from cells of premalignant adenomas and cancers into the stool. Potentially, both preclinical and clinical colorectal cancer may be detected. Panels of multiple DNA markers are used to ensure a high sensitivity for colorectal cancer.In this article, several advantages of the stool DNA test (compared with current colorectal cancer screening methods) are discussed. The stool DNA test may be more patient-friendly and has a higher degree of sensitivity and specificity for colorectal cancer. No bowel or dietary preparation is required and the test is noninvasive. The stool DNA test screens the entire colon and may detect some other types of cancers proximal to the colon. In the future, there may be potential to use the stool DNA test to screen for aerodigestive cancers (lung, esophageal, gastric, and pancreatic), in addition to colorectal cancer. An improved noninvasive screening test would help allocate colonoscopy resources to those patients who would benefit the most. Colorectal cancer screening cost-effectiveness may also be improved.Some limitations of the stool DNA test include the need for clinical studies in average-risk populations and marker refinement. An automated testing system may help reduce costs and turnaround times. Despite recognized limitations, the stool DNA test is a promising new diagnostic tool with the potential to improve effectiveness of colorectal cancer screening.     

Heterogeneity of DNA methylation status analyzed by bisulfite-PCR-SSCP and correlation with clinico-pathological characteristics in colorectal cancer.

Aberrant DNA methylation has been identified as an important mechanism for inactivation of tumor suppressor genes and mismatch repair genes during carcinogenesis. We used bisulfite treatment and the PCR-single strand conformation polymorphism (SSCP) (BiPS) technique to analyze methylation status of the promoter regions of the hMLH1, p16, and HIC1 genes in several cancer cell lines and colorectal cancer tissues. The methylation of the hMLH1, p16 and HIC1 genes was observed in 2, 8, and 13 of 13 cancer cell lines, respectively. The SSCP for p16 and HIC1 in each of the methylation-positive cell lines were similar, indicating relative homogeneity of methylation status and complete methylation in the cell lines. Methylation was observed in 8, 5, and 21 of 25 colorectal cancer tissues for the hMLH1, p16, and HIC1 genes, respectively. The methylated bands revealed by BiPS analysis of the hMLH1 gene were homogeneous, whereas those of the p16 and HIC1 genes were different in each case. The methylation of the promoter region of the HIC1 gene in colorectal cancer was observed most frequently and could serve as a sensitive marker for colorectal cancer. Methylation status of the hMLH1 and p16 gene promoters was correlated with microsatellite instability status, tumor location, and differentiation but not with K-ras mutation or allelic loss of p53.     

MSP-DHPLC技术检测MGMT基因甲基化的应用评价

目的 应用变性高效液相色谱(DHPLC)结合甲基化特异性PCR(MSP),建立一种临床可行的MGMT基因启动子甲基化检测方法,并探讨其灵敏度和特异性.方法 选取MGMT甲基化标准品、30例脑胶质瘤组织和5例正常脑组织作为研究对象,分别应用MSP和MSP-DHPLC方法进行MGMT基因启动子区甲基化检测,比较两种方法的检...