胃癌组织中sfrp5的甲基化表达及其临床意义

发布时间：2018-03-09 15:53

本文选题：胃癌　切入点：基因甲基　出处：《河北医科大学》2016年硕士论文　论文类型：学位论文

【摘要】：胃癌(gastric cancer)占胃部恶性肿瘤的95%以上,其病死率在全球范围内居恶性肿瘤的第2位,2012年数据,我国胃癌发病率占全球43%,死亡率占45%,而早期胃癌仅占10%左右。胃癌在我国仍是最常见的恶性肿瘤之一,是威胁人类健康的一类常见疾病。大量最新研究结果充分表明了基因组学与表观遗传学共同机制在促进肿瘤发生、发展过程中的重要性并展现出令人乐观的临床应用前景。在基因修饰过程中,甲基化将直接影响着一个基因的活性,这是表观遗传修饰过程中极其重要的方式。近年来有学者发现Wnt信号通路的异常激活与肿瘤的发生、发展有着密切的关系。尤其是此过程中基于启动子甲基化致使Wnt信号通路拮抗因子分泌型卷曲相关蛋白(secreted frizzled-related proteins,Sfrp)的沉默或表达活性的严重受抑制促进了肿瘤的形成及发展的过程。目的:本研究旨在探讨胃癌组织及对应的癌旁正常组织中Sfrp5基因甲基化修饰及蛋白表达与临床病理参数的关系并探讨其临床意义。方法:1选择石家庄市第一医院外科手术切除并病理证实为胃癌的新鲜癌组织及其新鲜癌旁正常组织各90例,胃癌患者中男性73例,女性17例;年龄46-76岁,平均年龄64岁;组织学分型:高、中分化腺癌35例,低分化55例。淋巴结转移:其中33例患者发生了邻近或远端淋巴结的受累,57例患者未发生淋巴结转移。取材部位:每例患者均在胃癌原发病变区和切除标本距离切缘大于5厘米处(正常未发生癌变)分别取材;新鲜组织置于液氮罐中暂存,另外一块组织经中性福尔马林固定,经脱水、透明制成蜡块,切片、常规HE染色切片经临床病理科医生的观察保证取材的准确性。所有患者术前均未经化疗和放疗,均有完整的临床和病理资料。不符合上述条件的标本被排除于研究之外。2甲基化特异性PCR(methylation specific PCR,MSP)被用于测定各例患者癌组织及正常组织中Sfrp5基因发生甲基化的状况,用免疫组织化学(Envision)法检测Sfrp5蛋白的表达情况,操作步骤严格按照试剂盒说明执行。3统计学分析。应用SPSS19.0版统计软件进行数据处理及统计学分析,计数资料以百分比表示,组间比较采用卡方检验和Fisher确切概率法分析,以P0.05认为有统计学差异。结果:1 Sfrp5在胃癌和癌旁正常组织中的蛋白表达和甲基化状态:免疫组化结果:Sfrp5蛋白在胃癌和癌旁正常组织中的阳性表达率分别为20%(18/90)和90%(81/90),不同组别间数据具有显著统计学差异(P0.05)。甲基化特异性PCR结果:Sfrp5基因在癌组织及癌旁组织中的甲基化频率分别为82.2%(74/90)和18.9%(17/90),差异有统计学意义(P0.05);2 Sfrp5基因甲基化与临床病理参数的关系:Sfrp5基因甲基化频率在无淋巴结转移组66.7%(22/33)显著低于有淋巴结转移组86.0%(49/57),差异有统计学意义(P0.05);高中分化组中Sfrp5基因的甲基化频率为71.4%(25/35)低分化组的甲基化率81.8%(45/55),但两组之间的差异不具有统计学意义(P0.05);大于等于50岁年龄组84.5%(71/84)低于小于50岁年龄组基因甲基化频率100%(6/6),女性组76.4%(13/17)低于男性组甲基化频率76.7%(56/73),但均无统计学差异(P0.05)。结论:Sfrp5基因高甲基化是其蛋白表达降低的重要原因并且可能与胃癌的发生、发展有关。
[Abstract]:Gastric cancer (gastric cancer) accounted for more than 95% of the stomach cancer, the mortality rate of malignant tumor in the world within the scope of the second, 2012 data, the incidence of gastric cancer in China accounted for 43% of global mortality accounted for 45%, while early gastric cancer accounted for only about 10%. Gastric cancer in our country is still one of the most common malignant tumors, is a kind of common disease threatening human health. A large number of the latest research results show that the genomic and epigenetic common mechanism in promoting tumorigenesis, the importance in the process of development and show the clinical application prospects of optimism. In the process of gene modification, methylation will directly affect the activity of a gene. This is an extremely important epigenetic modification in the process. In recent years, some scholars have found that the abnormal activation of Wnt signaling pathway with tumor occurrence, development has a close relationship. Especially a promoter based on this process The base that Wnt signaling pathway antagonist secreted frizzled related protein (secreted frizzled-related, proteins, Sfrp) or silence the expression activity was inhibited seriously promote the formation and development of tumor. Objective: This study aimed to investigate the methylation of Sfrp5 gene in gastric cancer tissues and corresponding adjacent normal tissue modification and protein expression with the clinicopathological parameters and to explore its clinical significance. Methods: 1. Select the first hospital of Shijiazhuang City surgical resection and pathology of gastric cancer and fresh fresh tissue adjacent normal tissues in 90 cases of gastric cancer patients, 73 were male, 17 were female; the age is 46-76 years old, the average age is 64 years old; histological type high, 35 cases of moderately differentiated adenocarcinoma, poorly differentiated 55 cases. Lymph node metastasis: 33 cases occurred in patients with adjacent or distant lymph node involvement, 57 patients without lymph node metastasis. The Ministry of materials A: all patients were in primary gastric lesions and resection margin distance greater than 5 cm (normal non cancerous) were drawn; fresh tissue in liquid nitrogen tank storage, another piece of tissue was fixed with formalin, dehydrated, transparent, paraffin slice, routine HE staining by to observe the clinical pathologist to ensure the accuracy of sampling. All the patients were not treated by chemotherapy and radiotherapy, the clinical and pathological data were complete. Do not meet the above conditions were excluded.2 methylation specific PCR (methylation specific PCR, MSP) was used to determine the methylation of Sfrp5 patients cancer tissue and normal tissue, gene, immunohistochemistry (Envision) method for detection of expression of Sfrp5 protein, operating procedures in strict accordance with the kit instructions.3 application SPSS19.0 version statistics statistical analysis. Software for data processing and statistical analysis, count data expressed as a percentage, comparison between groups using chi square test and Fisher exact probability analysis, to P0.05 that there was statistically significant difference. Results: 1 Sfrp5 in gastric carcinoma and adjacent normal tissues, protein expression and methylation state: the results of immunohistochemistry: the positive expression of Sfrp5 protein in gastric carcinoma and adjacent normal tissues were respectively 20% (18/90) and 90% (81/90), the data between different groups with significant difference (P0.05). Results: the methylation specific PCR methylation frequency of Sfrp5 gene in cancer tissues and in respectively 82.2% and 18.9% (74/90) (17/90), the difference was statistically significant (P0.05); 2 the relationship between Sfrp5 gene methylation and clinicopathological parameters: Sfrp5 gene methylation frequency in the group without lymph node metastasis 66.7% (22/33) with lymph node metastasis was significantly lower than that of group 86% (49/57), the difference was statistically Statistically significant (P0.05); the methylation frequency of Sfrp5 gene differentiated group was 71.4% (25/35) methylation rate of 81.8% low differentiation group (45/55), but the difference between the two groups was not statistically significant (P0.05); greater than or equal to 50 year old age group 84.5% (71/84) lower than that of less than 50 year old age group methylation frequency of 100% (6/6), female group 76.4% (13/17) lower than the male group. The methylation frequency of 76.7% (56/73), but there was no significant difference (P0.05). Conclusion: Sfrp5 gene methylation is an important cause of reduced protein expression and may be related to gastric carcinogenesis and development.

【学位授予单位】：河北医科大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：R735.2

【参考文献】