一个多发性内分泌腺瘤病2型家系的RET 基因检测

目的：对一个多发性内分泌腺瘤病2型（ multiple endocrine neoplasia 2,MEN2）家系进行RET基因检测,明确诊断和分型,指导治疗、预防及改善预后。方法采用聚合酶链反应和直接基因测序的方法,对一个临床诊断MEN2的家系（共3名家系成员）和3例正常对照的RET原癌基因21个外显子进行测序。结果该家系中的2例患者和1例无症状一级亲属均为RET原癌基因外显子11第634号密码子位点的杂合错义突变TGC→CGC,半胱氨酸→精氨酸（ C634R）。结论通过RET基因检测明确该家系为多发性内分泌腺瘤病2A型,对家系中患者的治疗和随访起到了指导作用,并筛查出家系中无症状的基因突变携带者。     

两个多发性内分泌腺瘤病2A型家系RET基因突变研究

目的总结2个多发性内分泌腺瘤病2A（MEN2A）型家系的临床特点,及MEN2A家系RET基因突变类型。方法对2个MEN2A家系进行临床调查,分析其临床特点。提取2个家系成员外周血基因组DNA,扩增先证者RET原癌基因的外显子10、11,13—16,并行Sanger测序,测得突变所在的外显子后,将其亲属相应外显子的扩增产物进行测序。结果家系1的先证者及其哥哥的10q11．2外显子11（密码子634）RET原癌基因发生点突变：Cys643Trp。家系2的先证者其兄长存在10q11。2外显子11（密码子634）RET原癌基因发生点突变：Cys643Arg,筛查出1个家系成员为基因突变携带者。结论RET原癌基因第11外显子Cys643Trp杂合突变及Cys634Arg杂合突变,均为MEN2A的致病基因．此2个家系患者虽然突变类型不同,但两家系患者在起病方式、发病年龄及临床表现均相似。基因检测是诊断MEN2A的有效方法。     

RET基因Cys 634 Trp突变致多发性内分泌腺瘤2A型

目的 明确一个多发性内分泌腺瘤2A型（MEN2A）家系致病基因PET的基因型。方法 应用PCR技术对RET基因的第10、11、13、14、15和16外显子进行扩增,将扩增产物纯化后双向测序。结果 先证者及其弟弟RET基因第10、13、14、15和16外显子均无异常,第11外显子的第14996位核苷酸存在C-G替代,其反义链测序为14996 G-C替代,这种替代（TGC-TGG）使编码的氨基酸由半胱氨酸突变为色氨酸（Cys 634 Trp,C 634 W）。正常对照RET基因的第10、11、13、14、15和16外显子区域均未见异常。结论 该MEN2A家系的遗传基础是RET基因Cys 634 Trp突变。     

多发性内分泌腺瘤病2A家系的RET原癌基因突变研究

目的检测一个多发性内分泌腺瘤病2A(MEN 2A)型家系的RET原癌基因突变情况.方法提取16名家系成员外周血基因组DNA,对RET原癌基因第11外显子进行聚合酶链反应(PCR),PCR产物进行直接基因测序.结果家系中1例病理确诊嗜铬细胞瘤的患者存在RET原癌基因第11外显子634密码子错义突变;另外筛查出2名家系成员为该突变基因携带者,其中1例经B超发现甲状腺结节性病灶伴血清降钙素升高.结论 MEN 2A的诊断达到了基因水平,对家系基因筛查可以早期诊断该疾病.     

多发性内分泌腺瘤病2A家系的RET原癌基因突变研究

目的 检测一个多发性内分泌腺瘤病2A(MEN 2A)型家系的RET原癌基因突变情况。方法 提取16名家系成员外周血基因组DNA，对RET原癌基因第ll外显子进行聚合酶链反应(PCR)，PCR产物进行直接基因测序。结果 家系中l例病理确诊嗜铬细胞瘤的患者存在RET原癌基因第ll外显子634密码子错义突变；另外筛查出2名家系成员为该突变基因携带者，其中l例经B超发现甲状腺结节性病灶伴血清降钙素升高。结论 MEN2A的诊断达到了基因水平，对家系基因筛查可以早期诊断该疾病。     

多发性内分泌腺瘤病2A型一例报告

目的讨论一例多发性内分泌腺瘤病2A型(MEN 2A)的特点.方法收集患者临床病史、生化和影像学检查结果;提取外周血基因组DNA,对RET原癌基因第11外显子进行聚合酶链反应,反应产物进行直接基因测序.结果该患者病理证实为双侧肾上腺嗜铬细胞瘤,同时伴有血清降钙素水平明显升高的甲状腺占位性病变以及血清PTH升高的甲状旁腺占位性病变(腺瘤);分子生物学研究发现患者存在RET原癌基因第11外显子634密码子错义突变.结论总结该病例的临床特点对早期发现、诊断和治疗该疾病具有指导意义.     

多发性内分泌腺瘤病2A型一例报告

目的 讨论一例多发性内分泌腺瘤病2A型(MEN2A)的特点。方法 收集患者临床病史、生化和影像学检查结果；提取外周血基因组DNA，对RET原癌基因第ll外显子进行聚合酶链反应，反应产物进行直接基因测序。结果 该患者病理证实为双侧肾上腺嗜铬细胞瘤，同时伴有血清降钙素水平明显升高的甲状腺占位性病变以及血清PTH升高的甲状旁腺占位性病变(腺瘤)；分子生物学研究发现患者存在RET原癌基因第ll外显子634密码子错义突变。结论 总结该病例的临床特点对早期发现、诊断和治疗该疾病具有指导意义。     

多发性内分泌腺瘤2A型家系筛查和RET基因突变研究

目的 探讨多发性内分泌腺瘤2A型（MEN2A）的临床诊治特点及RET基因检测的意义.方法 对1976年6月至2013年2月间诊治的1个MEN2A家系共21例家庭成员进行系统家系调查,提取外周血进行RET基因和血清基础降钙素（Ct）水平检测.结果 基因检测家系内共10例家庭成员存在RET基因第11外显子p.C634Y 突变（10/21）,与临床完全符合.10例MEN2A患者中,男8例,女2例.7例甲状腺髓样癌（MTC）首次平均诊断年龄34.3（21-55）岁;肿瘤平均最大直径2.8（0.8-3.7）cm,5例接受了不规范的甲状腺切术,2例接受双侧甲状腺切除＋改良的双侧颈部淋巴结清扫,其中1例同期伴发甲状腺乳头状癌.平均随访172.4（10-440）个月,术后4例血清Ct水平升高,3例正常.7例中3例伴发双侧肾上腺嗜铬细胞瘤（PHEO;2例同时,1例异时）,平均首次诊断年龄48.3（42-58）岁,肿瘤平均最大直径7.0（4.4-8.5）cm;均接受了保留肾上腺皮质功能的PHEO切除术.分别随访15、17、120个月,未发生肾上腺皮质功能低下和复发、转移.通过家系调查发现的其中3例无症状RET基因突变携带者,平均年龄11.7（8-15）岁,均已随访17个月,Ct水平仍均轻度升高,均拒绝手术.结论 提高对MEN2A的认识和认知水平,整合临床筛查和RET基因检测,有利于MEN2A的及早诊断和规范化治疗,可减少手术并发症和提高远期治愈率.     

多内分泌腺瘤病研究进展

多内分泌腺瘤病1型(MEN1)发生的重要原因是MEN1基因突变,导致肿瘤细胞11号染色体不同程度的杂合缺失,menin蛋白消失,临床主要表现有甲状旁腺腺瘤、胃肠胰腺内分泌肿瘤和垂体前叶瘤。多内分泌腺瘤病2型(MEN2)主要由原癌基因RET突变所致,又分为MEN2A和MEN2B,临床表现为甲状腺髓样癌、嗜铬细胞瘤、甲状旁腺增生和黏膜神经纤维瘤。RET基因突变类型有一定的规律性,即基因型和表现型之间有非常好的相关性。本文将主要介绍MEN1和MEN2发生机制方面的最新研究进展。     

多内分泌腺瘤病研究进展

多内分泌腺瘤病1型(MEN1)发生的重要原因是MEN1基因突变,导致肿瘤细胞11号染色体不同程度的杂合缺失,menin蛋白消失,临床主要表现有甲状旁腺腺瘤、胃肠胰腺内分泌肿瘤和垂体前叶瘤.多内分泌腺瘤病2型(MEN2)主要由原癌基因RET突变所致,又分为MEN2A和MEN2B,临床表现为甲状腺髓样癌、嗜铬细胞瘤、甲状旁腺增生和黏膜神经纤维瘤.RET基因突变类型有一定的规律性,即基因型和表现型之间有非常好的相关性.本文将主要介绍MEN1和MEN2发生机制方面的最新研究进展.     

Germline RET mutations in exons 10 and 11: an Iranian survey of 57 medullary thyroid carcinoma cases

The susceptibility gene for hereditary Medullary Thyroid Carcinoma (MTC) is the RET proto-oncogene. The aim of this study was to evaluate the prevalence of common germline RET mutations in exons 10 and 11 among Iranian MTC patients. Fifty-seven non-related MTC patients were examined in this study (Females: Males =1.2:1.0, Mean age = 40.0 +/- 11.5 years) and the existence of mutations was assessed through the PCR-RFLP technique. The only Multiple Endocrine Neoplasia type 2A (MEN2A) patient displayed a C634W mutation in exon 11. Among 53 apparently sporadic MTC patients, one patient showed a C620R mutation in exon 10 and two other patients displayed C624Y mutations in exon 11 of RET proto-oncogene. Neither the only Multiple Endocrine Neoplasia type 2B (MEN2B) patient nor two Familial MTC patients was found to carry germline mutations in exons 10 and 11. This study reports, for the first time, the prevalence of common RET mutations among Iranian, apparently sporadic MTC patients, underlining the critical importance of screening for RET mutations in such patients.     

DelD631:多发性内分泌腺瘤病2A型RET原癌基因的一个新突变

目的 检测一个多发性内分泌腺瘤病2A型（MEN2A）家系中RET原癌基因突变情况,以探寻该家系发病的分子机制。方法一个MEN2A家系,包括先证者两代人共22位成员的大家系。提取该家系22位成员外周血基因组DNA,扩增先证者RET原癌基因的外显子10、11,进而对纯化后的PCR产物直接测序,并进一步进行克隆测序,判定变异的位点及编码氨基酸序列的变化,测得突变所在的外显子后,将其余几例患者及其亲属相应外显子的扩增产物进行测序。结果 4例MEN2A患者均存在13631密码子（GAC）的杂合缺失,碱基序列由TGC^∧GACGAGCTG变为TGCGAGCTG,导致代表天冬氨酸的13631的缺失,即delD631;4例患者中Ⅱ6的一级亲属（Ⅲ10）为该基因突变携带者。克隆测序发现的突变点与Cariff医学遗传学院人类基因突变数据库收录的MEN2A相关的RET原癌基因突变比较,确定为新突变点。结论 本研究MEN2A家系存在外显子11的13631杂合缺失突变,是国内外报道的首个RET原癌基因13631缺失突变。临床表现特点：相对于半胱氨酸位点突变,其发病年龄迟,肾上腺嗜铬细胞瘤可早于甲状腺髓样癌发生。     

RET oncogene mutations in medullary thyroid carcinoma in Mexican families

BACKGROUND: Different RET oncogene mutations have been found to be associated with inherited medullary thyroid carcinoma (MTC) in the context of three different syndromes including multiple endocrine neoplasia types 2A (MEN 2A) and 2B (MEN 2B) and familial medullary thyroid carcinoma (FMTC). These mutations have been recorded in different populations, but to date there is no corresponding study in Mexican families. Our purpose was identification of RET mutations in Mexican families with inherited or sporadic MTC (SMTC) and search for RET protein expression as prognostic marker in MTC tumors. METHODS: Nine unrelated families with MTC corresponding either to two MEN 2A, three MEN 2B, or four SMTC were studied. Screening of exons 10, 11, and 13-16 of RET oncogene in DNA from circulating lymphocytes and tumor samples were analyzed. Immuno- staining for RET was performed in the corresponding tumor. RESULTS: Germline 918 ATG-->ACG RET mutation was present in three unrelated MEN 2B individuals and corresponding somatic mutation in one individual with SMTC; 634 TGC-->TTC RET mutation was detected in two related patients in an MEN 2A family and the 634 TGC-->TAC RET mutation was detected in 12 related individuals from a second MEN 2A family. RET protein expression was detected in all MTC tumors showing different staining intensity. CONCLUSIONS: RET mutations found in Mexican patients with MTC are similar to those previously reported in several MTC families worldwide. This indicates that RET mutations are highly conserved and that MTC etiology does not depend to a great extent on environmental factors or ethnic differences. Detection of RET protein in MTC tissue sections is not useful as prognostic marker.     

多发性内分泌腺瘤2A 型家系的临床筛查及预防性甲状腺全切除术

目的：探讨多发性内分泌腺瘤2A型（multiple endocrine neoplasia type 2A,MEN 2A）家系筛查的临床意义和进行预防性甲状腺全切除的可行性和有效性。方法对一个MEN 2A家系行家系调查,提取外周血行RET原癌基因和降钙素检测,并对无症状的基因突变携带者行预防性甲状腺全切除术。结果基因检测该家系为RET原癌基因第11外显子第634位点TGC→CGC杂合错义突变,即p．C634R突变,与MEN 2A患者临床表型-甲状腺髓样癌（ medullary thyroid carcinoma ,MTC）或MTC伴肾上腺嗜铬细胞瘤（ pheochromocytom ,PHEO）完全共分离。6例MEN 2A中,男4例,女2例;首次诊断平均年龄33.5（19～65）岁;MTC平均直径2.3（0.7～5.2）cm。其中3例以颈部占位或伴腹泻就诊,接受了不规范的甲状腺切除术或＋双侧Ⅵ区淋巴结清扫或＋侧颈部淋巴结清扫;T2N1bM02例,T3N1bM01例。3例无症状者中2例行预防性甲状腺切除＋双侧Ⅵ区淋巴结清扫,另1例行双侧甲状腺全切除＋双侧Ⅵ区淋巴结清扫＋右侧颈淋巴结清扫术;T1N0M02例,T1N1bM01例。仅见1例无症状者伴发左侧PHEO（1/6）并优先于MTC接受了左侧PHEO切除。6例术后4例降钙素仍升高,其中有症状中的1例（ T3N1bM0）先后接受了4次颈部手术,仍于首次术后130个月出现多处骨转移伴骨痛（T3N1bM1）,服用范得他尼2个月后骨痛消失,至今带瘤生存32个月;另外有症状和无症状者各1例（T2N1bM0和T1N1bM0）,分别在首次术后6、7个月接受了再次手术,包括另1例未再次手术的有症状者（T2N1bM0）,3例至今分别已22、22和20个月,降钙素仍升高。其余2例无症状患者（T1N0M0）术后已随访20个月,降钙素均＜2.0 ng/L。结论对MEN 2A家系进行临床筛查,有利于早期诊断和治疗,改善预后;术前整合RET基因和降钙素检测,对无症状基因突变携带者进行预防性全甲状腺切除是可行、有效的。     

Diagnosis and surgical treatment of multiple endocrine neoplasia

Background Multiple endocrine neoplasia (MEN) is relatively rare. But more patients could be found by detailed examination. We discuss the diagnosis and surgical treatment of MEN. Methods The clinical data of 95 MEN cases were retrospectively analyzed. There were 30 cases of MEN1 including 19 cases from 6 families. The MEN1 gene mutation was detected in 81.48% of cases admitted after 1997. There were 22 cases of primary hyperparathyroidism (PHPT), 10 cases of enteropanceatic tumor including 9 cases of insulinoma, 15 cases of pituitary adenoma, 9 cases of adrenal adenoma, 2 cases of thymic carcinoid. Two patients had 4 glands involved, 3 patients had 3 glands involved, 16 patients had 2 glands involved, and 6 patients had only one gland involved. Three patients had neither clinical symptoms nor biochemical changes, and was diagnosed by MEN1 gene mutation. Six patients presented with nephrolithasis and 6 patients had impaired pancreatic endocrine function. There were 60 cases of MEN2a and 5 cases of MEN2b. 58 cases of MEN2a belongs to 19 kindreds. All MEN2a patients but one presented RET gene mutation in codon 634, and all MEN2b cases had mutation in codon 918. 48 cases of MEN2a had thyroid masses with elevated calcitonin levels. 27 patients had pheochromocytoma including 12 cases of multiple loci and 5 malignancy. 13 patients presented with hyperparathyroidism. 5 MEN2b patients had medullary thyroid carcinoma and mucosal ganglioneuromatosis with Marfanoid. Among them, 3 patients had bilateral pheochromocytoma. Results In MEN1, subtotal parathyroidectomy was performed in 12 patients with PHPT and one patient received parathyroid adenoma enucleation. Insulinomas were enucleated in 4 patients. Two patients underwent thymus tumor extirpation. Total thyroidectomy with bilateral dissection of regional lymph nodes was performed in 16 patients with MEN2a and nodule enucleation was performed in 9 patients. Twenty two MEN2a patients underwent pheochromocytoma enucleation including bilateral adrenal resection in 10 cases. 5 MEN2b patients underwent total thyroidectomy with bilateral lymph node dissection. Among them, 3 cases underwent bilateral adrenal operations. Conclusions MEN varies in symptoms. Germline mutation test is helpful in establishing a diagnosis. Surgical management should be aimed at the improvement of life quality in MEN1 and prevention of the fetal tumors in MEN2.     

Diagnosis and surgical treatment of multiple endocrine neoplasia

Background Multiple endocrine neoplasia (MEN) is relatively rare. But more patients could be found by detailed examination. We discuss the diagnosis and surgical treatment of MEN. Methods The clinical data of 95 MEN cases were retrospectively analyzed. There were 30 cases of MEN1 including 19 cases from 6 families. The MEN1 gene mutation was detected in 81.48% of cases admitted after 1997. There were 22 cases of primary hyperparathyroidism (PHPT), 10 cases of enteropanceatic tumor including 9 cases of insulinoma, 15 cases of pituitary adenoma, 9 cases of adrenal adenoma, 2 cases of thymic carcinoid. Two patients had 4 glands involved, 3 patients had 3 glands involved, 16 patients had 2 glands involved, and 6 patients had only one gland involved. Three patients had neither clinical symptoms nor biochemical changes, and was diagnosed by MEN1 gene mutation. Six patients presented with nephrolithasis and 6 patients had impaired pancreatic endocrine function. There were 60 cases of MEN2a and 5 cases of MEN2b. 58 cases of MEN2a belongs to 19 kindreds. All MEN2a patients but one presented RET gene mutation in codon 634, and all MEN2b cases had mutation in codon 918. 48 cases of MEN2a had thyroid masses with elevated calcitonin levels. 27 patients had pheochromocytoma including 12 cases of multiple loci and 5 malignancy. 13 patients presented with hyperparathyroidism. 5 MEN2b patients had medullary thyroid carcinoma and mucosal ganglioneuromatosis with Marfanoid. Among them, 3 patients had bilateral pheochromocytoma. Results In MEN1, subtotal parathyroidectomy was performed in 12 patients with PHPT and one patient received parathyroid adenoma enucleation. Insulinomas were enucleated in 4 patients. Two patients underwent thymus tumor extirpation. Total thyroidectomy with bilateral dissection of regional lymph nodes was performed in 16 patients with MEN2a and nodule enucleation was performed in 9 patients. Twenty two MEN2a patients underwent pheochromocytoma enucleation including bilateral adrenal resection in 10 cases. 5 MEN2b patients underwent total thyroidectomy with bilateral lymph node dissection. Among them, 3 cases underwent bilateral adrenal operations. Conclusions MEN varies in symptoms. Germline mutation test is helpful in establishing a diagnosis. Surgical management should be aimed at the improvement of life quality in MEN1 and prevention of the fetal tumors in MEN2.