The FOXE1 and NKX2-1 loci are associated with susceptibility to papillary thyroid carcinoma in the Japanese population.

Background FOXE1 and NKX2-1 are two known genetic risk factors for the predisposition to sporadic papillary thyroid carcinoma (PTC) in Europeans, but their association in other ethnicities is still unknown. Objective We aim to examine the association of the two genes with Japanese sporadic PTC, which exhibits high BRAF(V600E) mutation rate. Methods 507 Japanese sporadic PTC cases and 2766 controls were genotyped for rs965513 (FOXE1) and rs944289 (NKX2-1). PTC cases were also examined for their BRAF(V600E) mutational status. Results The association of both rs965513 (p=1.27×10(-4), OR=1.69, 95% CI 1.29 to 2.21) and rs944289 (p=0.0121, OR=1.21, 95% CI 1.04 to 1.39) with the risk of sporadic PTC was confirmed. Subgroup analysis based on the BRAF mutational status showed strong association of rs965513 with BRAF(V600E)-positive cases (p=2.26×10(-4), OR=1.72, 95% CI 1.29 to 2.29), but not with BRAF(V600E)-negative cases (p=0.143, OR=1.52, 95% CI 0.87 to 2.65). However, there was no difference in the observed effect size between both subgroups. For rs944289, both subgroups showed marginal association (p=0.0585, OR=1.17, 95% CI 0.99 to 1.37 for BRAF(V600E)-positive cases; p=0.0492, OR=1.35, 95% CI 1.00 to 1.81 for BRAF(V600E)-negative cases). Conclusions Both FOXE1 and NKX2-1 were associated with the increased risk of sporadic Japanese PTC. No clear associations were observed for either SNP with BRAF(V600E) status

The Common Genetic Variant rs944289 on Chromosome 14q13.3 Associates with Risk of Both Malignant and Benign Thyroid Tumors in the Japanese Population

Background: Several single nucleotide polymorphisms (SNP) have been identified to be associated with the risk for differentiated thyroid cancer in populations of distinct ethnic background. The relationship of these genetic markers to a benign tumor of the thyroid, follicular adenoma (FA), is not well established. Methods: In a multicenter retrospective case-control study, five thyroid cancer-related SNPs - rs966513 (9q22.33, FOXE1), rs944289 (14q13.3, PTCSC3), rs2439302 (8p12, NRG1), rs1867277 (9q22.23, FOXE1), and rs6983267 (8q24, POU5F1B) - were genotyped in 959 cases of histologically verified FA, 535 papillary thyroid carcinomas (PTC), and 2766 population controls. Results: A significant association was found between FA and rs944289 (p=0.002; OR 1.176 [CI 1.064-1.316]), and suggestively with rs2439302 (p=0.033; OR 1.149 [CI 1.010-1.315]). In PTC, significant associations were confirmed for rs965513 (p=4.21E-04; OR 1.587 [CI 1.235-2.000]) and rs944289 (p=0.003; OR 1.234 [CI 1.075-1.408]), newly found for rs2439302 (p=0.003; OR 1.266 [CI 1.087-1.493]) and rs1867277 (p=1.17E-04; OR 1.492 [CI 1.235-1.818]), and was not replicated for rs6983267 (p=0.082; OR 1.136 [CI 0.980-1.316]) in this series. A significant correlation between rs2439302 genotype and relative expression of NRG1 was detected in normal and tumor counterparts of PTC (about 10% decrease per each risk allele). NRG1 expression also significantly correlated with that of PTCSC3. Conclusions: Association of rs944289, which was previously known to confer risk for thyroid cancer, with FA, and the correlation between PTCSC3 and NRG1 expression demonstrates that predisposing genetic factors are partly common for benign and malignant thyroid tumors, and imply broader roles of the pathways they underlie in thyroid tumorigenesis, not limited to carcinogenesis

Copy Number Alteration and Uniparental Disomy Analysis Categorizes Japanese Papillary Thyroid Carcinomas into Distinct Groups

The aim of the present study was to investigate chromosomal aberrations in sporadic Japanese papillary thyroid carcinomas (PTCs), concomitant with the analysis of oncogene mutational status. Twenty-five PTCs (11 with BRAFV600E, 4 with RET/PTC1, and 10 without mutation in HRAS, KRAS, NRAS, BRAF, RET/PTC1, or RET/PTC3) were analyzed using Genome-Wide Human SNP Array 6.0 which allows us to detect copy number alteration (CNA) and uniparental disomy (UPD), also referred to as copy neutral loss of heterozygosity, in a single experiment. The Japanese PTCs showed relatively stable karyotypes. Seven cases (28%) showed CNA(s), and 6 (24%) showed UPD(s). Interestingly, CNA and UPD were rarely overlapped in the same tumor; the only one advanced case showed both CNA and UPD with a highly complex karyotype. Thirteen (52%) showed neither CNA nor UPD. Regarding CNA, deletions tended to be more frequent than amplifications. The most frequent and recurrent region was the deletion in chromosome 22; however, it was found in only 4 cases (16%). The degree of genomic instability did not depend on the oncogene status. However, in oncogene-positive cases (BRAFV600E and RET/PTC1), tumors with CNA/UPD were less frequent (5/15, 33%), whereas tumors with CNA/UPD were more frequent in oncogene-negative cases (7/10, 70%), suggesting that chromosomal aberrations may play a role in the development of PTC, especially in oncogene-negative tumors. These data suggest that Japanese PTCs may be classified into three distinct groups: CNA+, UPD+, and no chromosomal aberrations. BRAFV600E mutational status did not correlate with any parameters of chromosomal defects

Spontaneous Slowing and Regressing of Tumor Growth in Childhood/Adolescent Papillary Thyroid Carcinomas Suggested by the Postoperative Thyroglobulin-Doubling Time

Background. Children and adolescents with papillary thyroid carcinomas (PTCs) have generally excellent prognoses despite their frequent extended disease. The tumor growth of young patients’ PTCs might show spontaneous slowing postoperatively. We compared young PTC patients’ postoperative thyroglobulin-doubling time (Tg-DT) with their preoperative hypothetical tumor volume-doubling time (hTV-DT). Methods. Fourteen PTC patients aged ≤18 years who underwent total thyroidectomy at Kuma Hospital in 1998–2016 had biochemically persistent disease postoperatively. We calculated their Tg-DTs and estimated their preoperative TV-DTs with the tumor size and the patient’s age at surgery, presuming that a single cancer cell was present at the patient’s birth. Results. Twelve patients had positive Tg-DTs ranging from 2.0 to 147 years, and the remaining two had negative Tg-DTs, indicating slow growth or even regression. The hTV-DTs were 0.3–0.6 years (median 0.5 years), which were significantly shorter than the Tg-DTs (p<0.001), indicating much faster growth preoperatively. The analyses of the nine patients without radioactive iodine administration (RAI) gave similar results (p<0.01). Conclusions. Irrespective of RAI, the patients’ postoperative Tg-DTs were significantly longer than their preoperative hTV-DTs and were negative values in two patients, indicating that the growth of these young patients’ PTCs had spontaneously slowed or even regressed postoperatively

Comparative frequency of four different types of pregnancy-associated thyrotoxicosis in a single thyroid centre

Abstract Background Pregnancy and delivery markedly influence thyroid function. However, the comparative prevalence of gestational thyrotoxicosis (GT), new onset of Graves’ disease during pregnancy (GD during pregnancy), postpartum destructive thyrotoxicosis (PPT), and postpartum Graves’ thyrotoxicosis (PPGD) has not yet been determined. Methods We prospectively registered and performed a review of 4127 consecutive non treated female patients with thyrotoxicosis, seen between August 2008 and December 2013 in our outpatient clinic of Kuma Hospital. 187 out of the 4127 women had new diagnosis of thyrotoxicosis during pregnancy or in the postpartum period. We investigated the prevalence of new diagnosis of GT, GD during pregnancy, PPT and PPGD and compared the characteristics of these types of thyrotoxicosis. The postpartum period is defined as twelve months after delivery. Results Out of 187 pregnant or postpartum women, we identified 30 (16.0%) with GT, 13 (7.0%) with GD during pregnancy, 42 (22.5%) with PPT, and 102 (54.5%) with PPGD. The onset time of thyrotoxicosis during pregnancy, i.e., both GT and GD during pregnancy, was delayed by a couple of weeks when hCG peaked at 10 gestational weeks. Seventy-six percent of patients with PPT developed thyrotoxicosis between delivery and 4 months postpartum; on the other hand, 83.3% of patients with PPGD developed thyrotoxicosis at 6 months postpartum or later. Conclusions We named gestational thyrotoxicosis, new onset of Graves’ disease during pregnancy, postpartum destructive thyrotoxicosis, and postpartum Graves’ thyrotoxicosis as pregnancy-associated thyrotoxicosis. A clinically significant number of women developed Graves’ disease in the postpartum period in a single thyroid centre