LIMD2 Is Overexpressed in BRAF V600E-Positive Papillary Thyroid Carcinomas and Matched Lymph Node Metastases

We previously described that LIM domain containing 2 (LIMD2) overexpression was closely correlated with metastatic process in papillary thyroid carcinoma (PTC). We here evaluated the expression of LIMD2 in a series of non-metastatic and metastatic PTC and their matched lymph node metastases via immunohistochemistry. LIMD2 was expressed in 74 (81%) of primary PTC and 35 (95%) of lymph node metastases. Sub-analysis performed in 37 matched samples demonstrated that in four cases, LIMD2 is expressed in lymph node metastases, while it is not expressed in primary tumors. Moreover, in eight cases, the staining intensity of LIMD2 was stronger in the patient-matched lymph node metastases than in the primary tumors. Next, the expression of LIMD2 was correlated with clinical pathological parameters and BRAF V600E and RET/PTC mutational status. The expression of LIMD2 in primary tumors was correlated with the presence of BRAF V600E mutation (P =?0.0338). Western blot analysis in thyroid cell lines demonstrated that LIMD2 is expressed in two PTC cell lines, while it is not expressed in normal thyroid and follicular thyroid carcinoma cell lines. Importantly, its expression was higher in a PTC cell line that harbors BRAF V600E mutation than in a PTC cell line that harbors RET/PTC1. The available genomic profiling data generated by The Cancer Genome Atlas Research Network confirmed that LIMD2 expression is higher in BRAF-like PTC samples. Our data suggest that LIMD2 may play an important role in the metastatic process of PTC, predominantly in BRAF V600E-positive tumors.     

Concurrent lymph node metastases of medullary and papillary thyroid carcinoma in a case with <Emphasis Type="Italic">RET</Emphasis> oncogene germline mutation

We report the case of a 72 yr-old woman who underwent total thyroidectomy and resection of neck lymph nodes because of a firm nodule in the right lobe, which was consistent with medullary thyroid carcinoma (MTC) on cytological examination. Histology showed multifocal bilateral MTC; a 2 mm papillary thyroid carcinoma (PTC) was also detected in the right lobe, next to a focus of MTC; five cervical lymph nodes contained MTC. In one right perithyroidal lymph node, concurrent metastases of MTC and PTC were demonstated. DNA analysis showed a point mutation in exon 14 at codon 804 of the RET proto-oncogene locus, as frequently found in cases of familial MTC (FMTC). To our knowledge, this case represents the first documented case of concurrent lymph node metastases of MTC and PTC in a patient with RET proto-oncogene germline mutation. We report this unique case, discuss related thyroid malignancies, and suggest possible underlying pathogenetic mechanisms.     

甲状腺乳头状癌中BRAFV599E点突变与RET/PTC融合基因的检测

目的检测甲状腺乳头状癌(PTC)及其他类型甲状腺良恶性肿瘤中BRAFV599E的点突变及 RET/PTC1、3融合基因的表达状况,探讨二者与PTC临床病理学特征的关系.方法用聚合酶链反应(PCR)及逆转录(RT)-PCR分别检测95例石蜡与新鲜甲状腺病变组织中BRAFV599E点突变和RET/PTC1、3融合基因.结果 (1)仅在PTC中检测到BRAFV599E的突变,突变率56%(37/66),在经典型PTC和高细胞型PTC中突变率分别为70%(29/41)和2/3,在滤泡型PTC及其他类型甲状腺病变中未检测到BRAFV599E的突变.统计学分析BRAF突变与性别、年龄、伴慢性淋巴细胞浸润及淋巴结转移无明显关系(P>0.05).(2)PTC中RET/PTC检出率21.2%(14/66),其中5例RET/PTC1阳性(7.6%),9例RET/PTC3阳性(13.6%).RET/PTC融合基因阳性的14例PTC中未检测到BRAFV599E突变.其余29例良恶性病例中未检测到RET/PTC融合基因.RET/PTC融合基因的表达与PTC的临床病理学特征无明显关系(P>0.05).结论 (1)BRAFV599E突变和RET/PTC融合基因是PTC较特征性的遗传学改变,可作为PTC诊断和鉴别诊断提供分子学的依据,BRAFV599E突变可能是甲状腺乳头状癌表型的重要决定因素之一;(2)BRAFV599E突变与PTC的经典型和高细胞型两种主要亚型密切相关;(3)BRAFV599E突变与RET/PTC融合基因可能在PTC中是独立事件.     

甲状腺乳头状癌BRAF基因突变的检测及临床意义

目的 了解甲状腺乳头状癌(papillary thyroid carcinoma,PTC)BRAF基因T1799A点突变的情况与临床病理学特征的关系.方法 应用聚合酶链反应及DNA直接测序法对43例PTC患者,20例非PTC甲状腺病变患者及40份正常甲状腺组织对照的新鲜标本进行BRAF基因检测.分析BRAF基因突变与性别、发病年龄、原发灶大小、甲状腺包膜外浸润、颈淋巴结转移及远处转移等临床病理学特征的关系.结果 43例PTC中1 7例检出BRAF基因T1799A点突变.检出率为39.5%,而在非PTC甲状腺病变患者和40份正常甲状腺组织未发现T1799A点突变.BRAF基因突变与PTC甲状腺包膜外浸润及颈淋巴结转移密切相关(P<0.05及P<0.05),与性别、发病年龄、原发灶大小及远处转移无关.结论 BRAF基因突变与颈淋巴结转移和甲状腺包膜外浸润密切相关,突变可能增加PTC的侵袭性并影响预后.     

甲状腺乳头状癌BRAF基因突变的检测及临床意义

目的 了解甲状腺乳头状癌(papillary thyroid carcinoma,PTC)BRAF基因T1799A点突变的情况与临床病理学特征的关系.方法 应用聚合酶链反应及DNA直接测序法对43例PTC患者,20例非PTC甲状腺病变患者及40份正常甲状腺组织对照的新鲜标本进行BRAF基因检测.分析BRAF基因突变与性别、发病年龄、原发灶大小、甲状腺包膜外浸润、颈淋巴结转移及远处转移等临床病理学特征的关系.结果 43例PTC中1 7例检出BRAF基因T1799A点突变.检出率为39.5%,而在非PTC甲状腺病变患者和40份正常甲状腺组织未发现T1799A点突变.BRAF基因突变与PTC甲状腺包膜外浸润及颈淋巴结转移密切相关(P<0.05及P<0.05),与性别、发病年龄、原发灶大小及远处转移无关.结论 BRAF基因突变与颈淋巴结转移和甲状腺包膜外浸润密切相关,突变可能增加PTC的侵袭性并影响预后.     

甲状腺乳头状癌BRAF基因突变的检测及临床意义

目的 了解甲状腺乳头状癌(papillary thyroid carcinoma,PTC)BRAF基因T1799A点突变的情况与临床病理学特征的关系.方法 应用聚合酶链反应及DNA直接测序法对43例PTC患者,20例非PTC甲状腺病变患者及40份正常甲状腺组织对照的新鲜标本进行BRAF基因检测.分析BRAF基因突变与性别、发病年龄、原发灶大小、甲状腺包膜外浸润、颈淋巴结转移及远处转移等临床病理学特征的关系.结果 43例PTC中1 7例检出BRAF基因T1799A点突变.检出率为39.5%,而在非PTC甲状腺病变患者和40份正常甲状腺组织未发现T1799A点突变.BRAF基因突变与PTC甲状腺包膜外浸润及颈淋巴结转移密切相关(P<0.05及P<0.05),与性别、发病年龄、原发灶大小及远处转移无关.结论 BRAF基因突变与颈淋巴结转移和甲状腺包膜外浸润密切相关,突变可能增加PTC的侵袭性并影响预后.     

甲状腺乳头状癌BRAF基因突变的检测及临床意义

目的 了解甲状腺乳头状癌(papillary thyroid carcinoma,PTC)BRAF基因T1799A点突变的情况与临床病理学特征的关系.方法 应用聚合酶链反应及DNA直接测序法对43例PTC患者,20例非PTC甲状腺病变患者及40份正常甲状腺组织对照的新鲜标本进行BRAF基因检测.分析BRAF基因突变与性别、发病年龄、原发灶大小、甲状腺包膜外浸润、颈淋巴结转移及远处转移等临床病理学特征的关系.结果 43例PTC中1 7例检出BRAF基因T1799A点突变.检出率为39.5%,而在非PTC甲状腺病变患者和40份正常甲状腺组织未发现T1799A点突变.BRAF基因突变与PTC甲状腺包膜外浸润及颈淋巴结转移密切相关(P<0.05及P<0.05),与性别、发病年龄、原发灶大小及远处转移无关.结论 BRAF基因突变与颈淋巴结转移和甲状腺包膜外浸润密切相关,突变可能增加PTC的侵袭性并影响预后.     

甲状腺乳头状癌BRAF基因突变的检测及临床意义

目的 了解甲状腺乳头状癌(papillary thyroid carcinoma,PTC)BRAF基因T1799A点突变的情况与临床病理学特征的关系.方法 应用聚合酶链反应及DNA直接测序法对43例PTC患者,20例非PTC甲状腺病变患者及40份正常甲状腺组织对照的新鲜标本进行BRAF基因检测.分析BRAF基因突变与性别、发病年龄、原发灶大小、甲状腺包膜外浸润、颈淋巴结转移及远处转移等临床病理学特征的关系.结果 43例PTC中1 7例检出BRAF基因T1799A点突变.检出率为39.5%,而在非PTC甲状腺病变患者和40份正常甲状腺组织未发现T1799A点突变.BRAF基因突变与PTC甲状腺包膜外浸润及颈淋巴结转移密切相关(P<0.05及P<0.05),与性别、发病年龄、原发灶大小及远处转移无关.结论 BRAF基因突变与颈淋巴结转移和甲状腺包膜外浸润密切相关,突变可能增加PTC的侵袭性并影响预后.     

甲状腺乳头状癌BRAF基因突变的检测及临床意义

目的 了解甲状腺乳头状癌(papillary thyroid carcinoma,PTC)BRAF基因T1799A点突变的情况与临床病理学特征的关系.方法 应用聚合酶链反应及DNA直接测序法对43例PTC患者,20例非PTC甲状腺病变患者及40份正常甲状腺组织对照的新鲜标本进行BRAF基因检测.分析BRAF基因突变与性别、发病年龄、原发灶大小、甲状腺包膜外浸润、颈淋巴结转移及远处转移等临床病理学特征的关系.结果 43例PTC中1 7例检出BRAF基因T1799A点突变.检出率为39.5%,而在非PTC甲状腺病变患者和40份正常甲状腺组织未发现T1799A点突变.BRAF基因突变与PTC甲状腺包膜外浸润及颈淋巴结转移密切相关(P<0.05及P<0.05),与性别、发病年龄、原发灶大小及远处转移无关.结论 BRAF基因突变与颈淋巴结转移和甲状腺包膜外浸润密切相关,突变可能增加PTC的侵袭性并影响预后.     

甲状腺乳头状癌BRAF基因突变的检测及临床意义

目的 了解甲状腺乳头状癌(papillary thyroid carcinoma,PTC)BRAF基因T1799A点突变的情况与临床病理学特征的关系.方法 应用聚合酶链反应及DNA直接测序法对43例PTC患者,20例非PTC甲状腺病变患者及40份正常甲状腺组织对照的新鲜标本进行BRAF基因检测.分析BRAF基因突变与性别、发病年龄、原发灶大小、甲状腺包膜外浸润、颈淋巴结转移及远处转移等临床病理学特征的关系.结果 43例PTC中1 7例检出BRAF基因T1799A点突变.检出率为39.5%,而在非PTC甲状腺病变患者和40份正常甲状腺组织未发现T1799A点突变.BRAF基因突变与PTC甲状腺包膜外浸润及颈淋巴结转移密切相关(P<0.05及P<0.05),与性别、发病年龄、原发灶大小及远处转移无关.结论 BRAF基因突变与颈淋巴结转移和甲状腺包膜外浸润密切相关,突变可能增加PTC的侵袭性并影响预后.     

甲状腺乳头状癌BRAF基因突变的检测及临床意义

目的 了解甲状腺乳头状癌(papillary thyroid carcinoma,PTC)BRAF基因T1799A点突变的情况与临床病理学特征的关系.方法 应用聚合酶链反应及DNA直接测序法对43例PTC患者,20例非PTC甲状腺病变患者及40份正常甲状腺组织对照的新鲜标本进行BRAF基因检测.分析BRAF基因突变与性别、发病年龄、原发灶大小、甲状腺包膜外浸润、颈淋巴结转移及远处转移等临床病理学特征的关系.结果 43例PTC中1 7例检出BRAF基因T1799A点突变.检出率为39.5%,而在非PTC甲状腺病变患者和40份正常甲状腺组织未发现T1799A点突变.BRAF基因突变与PTC甲状腺包膜外浸润及颈淋巴结转移密切相关(P<0.05及P<0.05),与性别、发病年龄、原发灶大小及远处转移无关.结论 BRAF基因突变与颈淋巴结转移和甲状腺包膜外浸润密切相关,突变可能增加PTC的侵袭性并影响预后.     

甲状腺乳头状癌BRAF基因突变的检测及临床意义

目的 了解甲状腺乳头状癌(papillary thyroid carcinoma,PTC)BRAF基因T1799A点突变的情况与临床病理学特征的关系.方法 应用聚合酶链反应及DNA直接测序法对43例PTC患者,20例非PTC甲状腺病变患者及40份正常甲状腺组织对照的新鲜标本进行BRAF基因检测.分析BRAF基因突变与性别、发病年龄、原发灶大小、甲状腺包膜外浸润、颈淋巴结转移及远处转移等临床病理学特征的关系.结果 43例PTC中1 7例检出BRAF基因T1799A点突变.检出率为39.5%,而在非PTC甲状腺病变患者和40份正常甲状腺组织未发现T1799A点突变.BRAF基因突变与PTC甲状腺包膜外浸润及颈淋巴结转移密切相关(P<0.05及P<0.05),与性别、发病年龄、原发灶大小及远处转移无关.结论 BRAF基因突变与颈淋巴结转移和甲状腺包膜外浸润密切相关,突变可能增加PTC的侵袭性并影响预后.     

甲状腺乳头状癌BRAF基因突变的检测及临床意义

目的 了解甲状腺乳头状癌(papillary thyroid carcinoma,PTC)BRAF基因T1799A点突变的情况与临床病理学特征的关系.方法 应用聚合酶链反应及DNA直接测序法对43例PTC患者,20例非PTC甲状腺病变患者及40份正常甲状腺组织对照的新鲜标本进行BRAF基因检测.分析BRAF基因突变与性别、发病年龄、原发灶大小、甲状腺包膜外浸润、颈淋巴结转移及远处转移等临床病理学特征的关系.结果 43例PTC中1 7例检出BRAF基因T1799A点突变.检出率为39.5%,而在非PTC甲状腺病变患者和40份正常甲状腺组织未发现T1799A点突变.BRAF基因突变与PTC甲状腺包膜外浸润及颈淋巴结转移密切相关(P<0.05及P<0.05),与性别、发病年龄、原发灶大小及远处转移无关.结论 BRAF基因突变与颈淋巴结转移和甲状腺包膜外浸润密切相关,突变可能增加PTC的侵袭性并影响预后.     

甲状腺乳头状癌BRAF基因突变的检测及临床意义

目的 了解甲状腺乳头状癌(papillary thyroid carcinoma,PTC)BRAF基因T1799A点突变的情况与临床病理学特征的关系.方法 应用聚合酶链反应及DNA直接测序法对43例PTC患者,20例非PTC甲状腺病变患者及40份正常甲状腺组织对照的新鲜标本进行BRAF基因检测.分析BRAF基因突变与性别、发病年龄、原发灶大小、甲状腺包膜外浸润、颈淋巴结转移及远处转移等临床病理学特征的关系.结果 43例PTC中1 7例检出BRAF基因T1799A点突变.检出率为39.5%,而在非PTC甲状腺病变患者和40份正常甲状腺组织未发现T1799A点突变.BRAF基因突变与PTC甲状腺包膜外浸润及颈淋巴结转移密切相关(P<0.05及P<0.05),与性别、发病年龄、原发灶大小及远处转移无关.结论 BRAF基因突变与颈淋巴结转移和甲状腺包膜外浸润密切相关,突变可能增加PTC的侵袭性并影响预后.     

The oncogenic activity of RET point mutants for follicular thyroid cells may account for the occurrence of papillary thyroid carcinoma in patients affected by familial medullary thyroid carcinoma

Activating germ-line point mutations in the RET receptor are responsible for multiple endocrine neoplasia type 2-associated medullary thyroid carcinoma (MTC), whereas somatic RET rearrangements are prevalent in papillary thyroid carcinomas (PTCs). Some rare kindreds, carrying point mutations in RET, are affected by both cancer types, suggesting that, under specific circumstances, point mutations in RET can drive the generation of PTC. Here we describe a family whose siblings, affected by both PTC and MTC, carried a germ-line point mutation in the RET extracellular domain, converting cysteine 634 into serine. We tested on thyroid follicular cells the transforming activity of RET(C634S), RET(K603Q), another mutant identified in a kindred with both PTC and MTC, RET(C634R) a commonly isolated allele in MEN2A, RET(M918T) responsible for MEN2B and also identified in kindreds with both PTC and MTC, and RET/PTC1 the rearranged oncogene that characterizes bona fide PTC in patients without MTC. We show that the various RET point mutants, but not wild-type RET, scored constitutive kinase activity and exerted mitogenic effects for thyroid PC Cl 3 cells, albeit at significantly lower levels compared to RET/PTC1. The low mitogenic activity of RET point mutants paralleled their reduced kinase activity compared to RET/PTC. Furthermore, RET point mutants maintained a protein domain, the intracellular juxtamembrane domain, that exerted negative effects on the mitogenic activity. In conclusion, RET point mutants can behave as dominant oncogenes for thyroid follicular cells. Their transforming activity, however, is rather modest, providing a possible explanation for the rare association of MTC with PTC.     

Familiäre Karzinome der Schilddrüse

Approximately 5% of differentiated thyroid carcinomas with follicular cell differentiation, papillary thyroid carcinoma (PTC) and follicular thyroid carcinoma (FTC) and 25–30% of medullary thyroid carcinoma (MTC) are hereditary. They occur either as part of a defined syndrome or are confined to the thyroid gland. Compared to their sporadic non-hereditary counterparts hereditary thyroid carcinomas generally develop earlier and regularly show multifocal tumour growth. With the exception of familial MTC, which is preceded by neoplastic C cell hyperplasia, no precursor lesions of hereditary thyroid carcinoma are known. In strong correlation with the localisation of the germline mutation of the RET protooncogene, familial MTC shows a distinct clinical course which allows precise clinical decision-making for prophylactic thyroidectomy to prevent invasive MTC. According to current knowledge prophylactic thyroidectomy of all other types of hereditary thyroid carcinoma is not justified.     

Diffuse sclerosing variant of papillary thyroid carcinoma: lack of BRAF mutation but occurrence of RET/PTC rearrangements.

Diffuse sclerosing variant of papillary thyroid carcinoma (PTC) is a rare tumour with a characteristic morphology as well as a strong preponderance for younger female patients. The T1799A missense mutation in exon 15 of the BRAF gene and RET/PTC rearrangement have been identified as the dominant genetic tumour initiation events in the pathogenesis of PTC leading to a constitutive activation of the RAS-RAF-MAPK pathway. In order to elucidate the pathogenesis of diffuse sclerosing variant of PTC, the prevalence of BRAF mutation and RET/PTC were determined by RT-polymerase chain reaction and DNA-sequence analysis in tumour samples of seven patients with this variant (all female, age range 15-61 years, mean 33.3 years) without prior radiation exposure. None of these cases showed a BRAF mutation. RET/PTC1 (two out of seven) and RET/PTC3 (one out of seven), which have been shown in large PTC series to comprise together more than 90% of RET/PTC types, were found in <50% of the cases investigated. All seven samples expressed the RET tyrosine kinase domain but lacked its extracellular domain potentially suggesting the existence of rare types of RET/PTC rearrangement in the four remained cases of diffuse sclerosing variant of PTC. Regarding this subtype, our study confirmed the paradigm of a mutual exclusivity between RET/PTC and BRAF in PTC. Additionally, this rare variant of papillary thyroid carcinoma may represent a tumour type susceptible to RET-targeted therapies.     

Synchronous Occurrence of Medullary and Papillary Carcinoma of the Thyroid in a Patient with Cutaneous Melanoma: Determination of BRAFV600E in Peripheral Blood and Tissues. Report of a Case and Review of the Literature

The purpose of this study is to describe a case of concurrent medullary and papillary thyroid carcinoma (MTC and PTC) and cutaneous melanoma and to analyze BRAF^V600E mutation in plasma and tissues. We report the clinical history and the laboratory, imaging, and histopathological findings of a 47-year-old man affected by multinodular goiter. BRAF^V600E-mutated DNA was quantified in plasma samples and in cancer sections by quantitative real-time polymerase chain reaction (qPCR). At ultrasound examination, the dominant right nodule of the thyroid was weakly hyperechoic and hypervascularized, while the left one was hypoechoic without internal vascularization. Regional lymphadenomegalia was not detected. Basal plasma calcitonin was elevated, and the patient underwent total thyroidectomy and resection of central cervical lymph nodes. Histopathological examination identified two distinct foci of MTC and PTC and micrometastasis of well-differentiated carcinoma in one of the six resected lymph nodes. RET proto-oncogene germline mutations were not detected. Cutaneous melanoma of the thorax was subsequently diagnosed. BRAF^V600E tissue DNA was detected in PTC and melanoma but not in MTC. The cell-free plasma percentage of BRAF^V600E DNA was detected in pre-thyroidectomy peripheral blood and was drastically reduced after cancer treatments. This study confirms the occurrence of synchronous MTC and PTC and is the first evidence of the co-existence of melanoma and distinct thyroid cancers of different origin. BRAF^V600E allele was detected in PTC and melanoma but not in MTC tissues. BRAF^V600E molecular quantification in pre- and post-treatment blood supports our previous data, suggesting its possible role in diagnosis and follow-up of BRAF-positive tumors.     

甲状腺乳头状癌中TROP-2表达的临床意义及其诊断价值

目的观察人类滋养层细胞表面抗原2(TROP-2)在甲状腺乳头状癌(papillary thyroid carcinoma,PTC)中的表达,探讨TROP-2在PTC中表达的临床意义及其诊断价值。方法采用免疫组化EnVision法检测100例甲状腺恶性病变(PTC 75例、滤泡性癌10例、髓样癌10例、差分化癌5例)、45例良性病变(正常甲状腺10例、结节性甲状腺肿10例、桥本甲状腺炎15例、滤泡性腺瘤10例),5例具有乳头样核特征的非浸润性甲状腺滤泡性肿瘤(non-invasive folliculaRthyroid neoplasms with papillary-like nucleaRfeatures,NIFTP)中TROP-2的表达;ARMS法检测PTC中BRAF V600E基因突变。分析TROP-2对PTC诊断的敏感性和特异性,及其与PTC临床病理特征以及BRAF V600E基因突变的关系。结果TROP-2在PTC中的阳性率为81.3%(61/75),在其他甲状腺恶性肿瘤和良性病变中均阴性,TROP-2对PTC诊断的敏感性为81.3%,特异性为100%。TROP-2表达与PTC淋巴结转移有关(P<0.05),与患者年龄、性别、肿瘤部位及临床分期无关(P>0.05),经典型PTC中TROP-2表达高于滤泡亚型PTC(P<0.05)。PTC中TROP-2表达与BRAF V600E基因突变呈正相关(P<0.05)。结论TROP-2是一种具有高度特异性和敏感性的诊断PTC的标志物,TROP-2检测可预测PTC的临床生物学行为和BRAF V600E基因突变状态,并对于形态学变形的PTC、微小型PTC和PTC的甲状腺内扩散的诊断和识别具有重要价值。