發(fā)布時間：2018-06-20 09:08

  本文選題：Lynch綜合征 + DNA錯配修復(fù)基因��； 參考：《昆明醫(yī)科大學(xué)》2017年碩士論文

【摘要】：[目的]Lynch綜合征是最常見的遺傳性結(jié)直腸癌綜合征之一。目前臨床中用以診斷Lynch綜合征的方法主要是對符合Amsterdam標準或Bethesda指南的患者行IHC檢測其病理組織中的MMR蛋白表達或進行MSI檢測,但這些方法無法避免一定的誤診及漏診。本文從1個符合AmsterdamⅡ臨床診斷標準的典型Lynch綜合征先證者及其家系成員入手,對先證者進行MMR蛋白表達檢測、MSI檢測,并應(yīng)用二代高通量測序?qū)ο茸C者進行遺傳性結(jié)直腸癌相關(guān)致病基因檢測,明確該家系致病突變基因及位點。從而評估各分子檢測的一致性,并對家系成員進行致病突變基因及位點的篩查和健康指導(dǎo),對臨床進行Lynch綜合征的診斷及家系健康管理進行探索。[方法]對臨床診療時經(jīng)CT及腸鏡等檢查發(fā)現(xiàn)多原發(fā)結(jié)腸癌且符合Amsterdam Ⅱ標準考慮為可疑Lynch綜合征的患者進行臨床評估后行結(jié)腸次全切除術(shù)。術(shù)后對切除標本行IHC檢測明確MMR蛋白表達情況,并行MSI檢測進一步明確患者微衛(wèi)星狀態(tài),隨后進行患者家系成員患病情況調(diào)查及回顧性調(diào)查追蹤尋訪,依據(jù)所掌握的資料繪制該家族的家系圖,再采用目標區(qū)域捕獲結(jié)合二代高通量測序技術(shù),對先證者及家系內(nèi)患者檢測相關(guān)基因外顯子及其附近±10bp內(nèi)含子區(qū)變異(包括點突變,20bp以內(nèi)的缺失插入突變)明確致病突變,并對家系內(nèi)其他成員行驗證實驗,分析他們的患病危險程度以進行健康指導(dǎo)。[結(jié)果]先證者CT及腸鏡檢查確定為多原發(fā)結(jié)腸癌,后行根治性結(jié)腸次全切除術(shù)。術(shù)后病理檢查提示:闌尾根部、降結(jié)腸高-中分化管狀腺癌,部分為粘液腺癌(大小分別為6cm×4cm×4cm;2.5cm×2cm×1cm);腸系膜淋巴結(jié)(5/28)見癌轉(zhuǎn)移。將病理標本行IHC染色提示MSH2及MSH6蛋白表達缺失,同時行MSI檢測提示MSI-H即微衛(wèi)星高度不穩(wěn)定。根據(jù)對患者家族史的追溯完成家系圖的繪制,發(fā)現(xiàn)先證者家系現(xiàn)在四代共有7名病理確證Lynch綜合征相關(guān)腫瘤患者,先證者(27歲)現(xiàn)罹患多原發(fā)結(jié)腸癌,先證者母親曾確診為子宮內(nèi)膜癌(52歲),已行手術(shù)治療,規(guī)律復(fù)查未再發(fā)相關(guān)腫瘤。先證者外祖母為多系統(tǒng)多原發(fā)腫瘤患者,先后罹患子宮內(nèi)膜癌(51歲)、乙狀結(jié)腸癌(64歲)及直腸癌(72歲),并于同年去世。先證者外祖母的3個兄弟分別罹患直腸癌,先證者另有1位表妹因罹患病理未明確腫瘤去世。對患者家族中11位成員采血提取DNA行基因檢測,證實家系內(nèi)患者均于MSH2基因檢出無義突變c.2038CT(p.Arg680Ter),導(dǎo)致MSH2基因編碼蛋白在第680位發(fā)生截短,為該家系致病突變。而在表現(xiàn)型正常家族成員中,2人行基因檢測確證為基因突變攜帶者,后行腸鏡檢查發(fā)現(xiàn)結(jié)直腸多發(fā)息肉,其余未發(fā)現(xiàn)攜帶該基因突變。[結(jié)論]本文所研究的Lynch綜合征家系疾病史連續(xù)4代,是符合Amsterdam Ⅱ標準的典型Lynch綜合征家系。先證者病理標本的IHC/MSI檢測與基因檢測結(jié)果一致,基因檢測結(jié)果提示了該家系的致病基因為MSH2基因的一個已知致病突變位點c.2038CT(p.Arg680Ter)。基因檢測有利于對Lynch綜合征患者進行家系內(nèi)篩查,并對進一步的遺傳學(xué)咨詢及家系健康管理提供了明確的依據(jù)。
[Abstract]:[Objective]Lynch syndrome is one of the most common hereditary colorectal cancer syndrome. At present, the main clinical use of the diagnosis of Lynch syndrome is to detect the expression of MMR protein in the pathological tissue of the patients with Amsterdam or Bethesda guidelines by IHC, or to perform MSI detection, but these methods can not avoid misdiagnosis and leakage. In this paper, we start with 1 typical Lynch syndromes and their family members, which conform to the Amsterdam II clinical diagnostic criteria, carry out MMR protein expression detection, MSI detection, and use two generation high-throughput sequencing to detect the hereditary colorectal cancer related genes and identify the gene and loci of the family. In order to evaluate the consistency of the various molecular detection, the screening and health guidance for the genes and loci of the family members, the diagnosis of Lynch syndrome and the health management of the family were explored. [Methods] multiple primary colon cancer was detected by CT and enteroscopy, and the Amsterdam II standard was considered for the clinical diagnosis and treatment. Patients with suspected Lynch syndrome underwent subtotal colectomy after clinical evaluation. After the operation, the expression of MMR protein was determined by IHC detection, and the microsatellite status of the patients was further confirmed by MSI detection. The family map, then the target region capture and two generation high-throughput sequencing technology, was used to detect the mutations in the exons of the related gene exons and their adjacent 10bp introns (including point mutations and 20bp deletion mutations) in the patients and their families, and to test the other members of the family and analyze them. [results] CT and colonoscopy were identified as multiple primary colon cancer, followed by radical colonic subtotal resection. Postoperative pathological examination suggested that O Nebe, high and middle differentiated tubular adenocarcinoma of the descending colon were mucous adenocarcinoma (6cm * 4cm x 4cm; 2.5cm * 2cm x 1cm); mesenteric lymph nodes. IHC staining showed that the expression of MSH2 and MSH6 protein was missing, and MSI was used to detect the high instability of the microsatellite. According to the family history of the patients, the family history of the patients had been traced, and the four generation of the first four generations of the patients were found to confirm the Lynch syndrome related tumor patients, the precursor (2). 7 years of age) suffered from multiple primary colon cancer. The first confirmed mother had been diagnosed with endometrial carcinoma (52 years old) and had undergone surgical treatment. The first syndrome was a multisystem, multiple primary tumor, with endometrial carcinoma (51 years old), sigmoid carcinoma (64 years old) and rectal cancer (72 years old), and died in the same year. The progenitor of the first syndrome was the progenitor of the precursor. The 3 brothers of the mother had rectal cancer respectively, and 1 other cousins died of a pathological undefined tumor. 11 members of the family had a DNA gene test, which confirmed that the MSH2 gene detected a nonsense mutation c.2038CT (p.Arg680Ter) in the family of the family, causing the MSH2 gene encoding protein to be truncated in 680th. Among the members of the normal family, 2 people were confirmed to be the carriers of the gene mutation, and the colonoscopy was used to detect multiple colorectal polyps, and the others were not found to carry the mutation. [Conclusion] the history of the family disease of Lynch syndrome was 4 generations, which was a typical Lynch ensemble in line with the standard of Amsterdam II. The IHC/MSI detection of the histopathological specimens of the first syndrome is consistent with the results of the gene detection. The gene detection results suggest that the pathogenic gene of the family is a known pathogenicity site c.2038CT (p.Arg680Ter) of the MSH2 gene. The gene detection is beneficial to the screening of the patients in the family of Lynch syndrome and the further genetic counseling. The family's health management provides a clear basis.
【學(xué)位授予單位】：昆明醫(yī)科大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2017
【分類號】：R735.3

【參考文獻】

相關(guān)博士學(xué)位論文 前1條

1 珠珠;云南省Lynch綜合征候選基因標志物研究[D];昆明醫(yī)科大學(xué);2014年

，

本文編號：2043748