Pathology and genetics of thyroid carcinoma

The effect of positive thyroglobulin antibodies on the prognosis and treatment response in patients with papillary thyroid carcinoma

Almost 15-30% of patients with papillary thyroid carcinoma (PTC) experience some degree of recurrence after treatment. Long-term follow-up and examination after thyroidectomy are very important in dealing with this issue. Serum thyroglobulin (Tg) level and neck ultrasound are the main part of follow-up for this purpose. The presence of thyroglobulin antibodies (TgAbs) leads to unreliable thyroglobulin (Tg) levels. The present study aims to evaluate the relationship between the simultaneous measurement of Tg and TgAb with long-term survival and response to treatment in these patients. This study was conducted by surveying available data from the medical records of 204 out of 600 patients over a 20-year period. In this research, 104 patients with positive TgAb were considered as the case group, and 100 patients with negative TgAb were selected as the control group. The relationship of TgAb titer was investigated with the staging, response to treatment (including the surgery number, number of radiotherapies, and dose of radioactive iodine), and recurrence in these patients. Also, the trend of TgAb changes was examined in the presence of high or low thyroglobulin levels during the follow-up period. Patients with high TgAb levels had more lymph node involvement, higher cumulative dose, a higher number of times received iodine, more surgical number, higher recurrence rate, and less excellent response (ER) to treatment during follow-ups. This effect of TgAb worsened in the presence of high Tg titer and remained up to 36 months. Overall, the baseline level of TgAb and its changes can be a suitable factor for predicting subsequent response to treatment and recurrence in patients with PTC. Accordingly, in cases with high TgAb and Tg levels, close follow-up should be considered up to Tg and TgAb normalization.

Advances and challenges in thyroid cancer: The interplay of genetic modulators, targeted therapies, and AI-driven approaches

Thyroid cancer continues to exhibit a rising incidence globally, predominantly affecting women. Despite stable mortality rates, the unique characteristics of thyroid carcinoma warrant a distinct approach. Differentiated thyroid cancer, comprising most cases, is effectively managed through standard treatments such as thyroidectomy and radioiodine therapy. However, rarer variants, including anaplastic thyroid carcinoma, necessitate specialized interventions, often employing targeted therapies. Although these drugs focus on symptom management, they are not curative. This review delves into the fundamental modulators of thyroid cancers, encompassing genetic, epigenetic, and non-coding RNA factors while exploring their intricate interplay and influence. Epigenetic modifications directly affect the expression of causal genes, while long non-coding RNAs impact the function and expression of micro-RNAs, culminating in tumorigenesis. Additionally, this article provides a concise overview of the advantages and disadvantages associated with pharmacological and non-pharmacological therapeutic interventions in thyroid cancer. Furthermore, with technological advancements, integrating modern software and computing into healthcare and medical practices has become increasingly prevalent. Artificial intelligence and machine learning techniques hold the potential to predict treatment outcomes, analyze data, and develop personalized therapeutic approaches catering to patient specificity. In thyroid cancer, cutting-edge machine learning and deep learning technologies analyze factors such as ultrasonography results for tumor textures and biopsy samples from fine needle aspirations, paving the way for a more accurate and effective therapeutic landscape in the near future.

Association of AXIN1 rs12921862 C/A and rs1805105 G/A and CTSB rs12898 G/A polymorphisms with papillary thyroid carcinoma: A case-control study

BACKGROUND

Papillary thyroid cancer (PTC) is the most common type of thyroid cancer which its precise etiology remains unknown. However, environmental and genetic factors contribute to the etiology of PTC. Axis inhibition protein 1 (Axin1) is a scaffold protein that exerts its role as a tumor suppressor. In addition, Cathepsin B (Ctsb) is a cysteine protease with higher expression in several types of tumors. Therefore, the aim of this study was to investigate the possible association of AXIN1 rs12921862 C/A and rs1805105 G/A and CTSB rs12898 G/A polymorphisms with PTC susceptibility.

MATERIALS & METHODS

In total, 156 PTC patients and 158 sex-, age-, and BMI-matched control subjects were enrolled in the study. AXIN1 rs12921862 C/A and rs1805105 G/A and CTSB rs12898 G/A polymorphisms were genotyped using the PCR-RFLP method.

RESULTS

There was a relationship between AXIN1 rs12921862 C/A polymorphism and an increased risk of PTC in all genetic models except the overdominant model. The AXIN1 rs1805105 G/A polymorphism was associated with an increased PTC risk only in codominant and overdominant models. The frequency of AXIN1 A_rs12921862 A_rs1805105 haplotype was higher in the PTC group and also this haplotype was associated with an increased risk of PTC. Moreover, the AXIN1 rs12921862 C/A polymorphism was not associated with PTC clinical and pathological findings, but AXIN1 rs1805105 G/A polymorphism was associated with almost three folds of larger tumor size (≥1 cm). There was no association between CTSB rs12898 G/A polymorphism and PTC and its findings.

CONCLUSION

The AXIN1 rs12921862 C/A and rs1805105 G/A polymorphisms were associated with PTC. AXIN1 rs1805105 G/A polymorphism was associated with higher tumor size.

The Value of Chinese Thyroid Imaging Report and Data System Combined With Contrast-Enhanced Ultrasound Scoring in Differential Diagnosis of Benign and Malignant Thyroid Nodules

OBJECTIVES

To explore the diagnostic value of contrast-enhanced ultrasound (CEUS) combined with the Chinese Thyroid Imaging Reporting and Data System (C-TIRADS) for differentiation of benign and malignant thyroid nodules.

METHODS

A retrospective analysis of the conventional ultrasound and CEUS data of 388 nodules in 355 patients who had undergone thyroid nodule resection was conducted. All nodules had clear pathological results. The CEUS observation indexes included the enhancement degree in the arterial phase (no enhancement, scant punctate-linear enhancement, mild enhancement, moderate enhancement, and high enhancement) and wash-out patterns (rapid wash-out, slow wash-out, and isochronous wash-out). Chi-square test between groups and receiver operating characteristic curves (ROC) were used to determine the malignant (+1 point) and benign (-1 point) observation indexes that were statistically significant for the differentiation between benign and malignant thyroid nodules. The CEUS and C-TIRADS malignant and benign indexes were combined to score and draw the ROC curve, which was compared with the ROC curve scored by C-TIRADS alone to compare the diagnostic efficacy of the two methods for differentiating between benign and malignant thyroid nodules.

RESULTS

Among the CEUS observation indexes, mild enhancement and rapid wash-out were malignant indexes, while isochronous wash-out was a benign index. The best diagnostic cut-off value for the differentiation of benign and malignant thyroid nodules using the C-TIRADS score and the C-TIRADS and CEUS combined score (C-TIRADS + CEUS score) was 2. The sensitivity, specificity, positive predictive values (PPV), and negative predictive values (NPV) of the two methods were 79.97, 75.48, 82.9, 70.5%, and 89.7, 72.9, 83.3, 82.5%, respectively. The area under the curve values were 0.840 and 0.877 (P < .001), respectively.

CONCLUSIONS

The CEUS feature of mild enhancement in the arterial phase and rapid wash-out pattern are suggestive of malignancy and isochronous wash-out pattern is suggestive of benignity. The C-TIRADS + CEUS score has a higher value for distinguishing benign from malignant thyroid nodules than the C-TIRADS score alone.

Genetic polymorphisms in the PCNXL2 gene are risk factors for thyroid cancer in the Chinese population

Background: Thyroid cancer is the most common endocrine malignancy and the fastest growing cancer worldwide. Thyroid cancer has the largest genetic component of all cancers. Previous genome-wide association studies indicated that genetic polymorphism in PCNXL2 is related to thyroid cancer susceptibility in European populations. This study aims to determine the influence of PCNXL2 polymorphisms on thyroid cancer risk in Chinese individuals. Methods: This case-control study identified four polymorphisms in PCNXL2 among 510 thyroid cancer cases and 509 healthy controls. The associations of PCNXL2 polymorphisms with thyroid cancer susceptibility were detected by calculating odds ratios. Multifactor dimensionality reduction was performed to detect the impact of SNP (single nucleotide polymorphism)-SNP interactions on the risk of thyroid cancer. Results: The study showed that rs10910660 in PCNXL2 was related to thyroid cancer susceptibility. Rs12129938 played a protective role in thyroid cancer susceptibility. Stratification analysis indicated that rs10910660 increased thyroid cancer risk at age >45 years. Rs12129938 enhanced susceptibility to thyroid cancer at age >45 years, while this SNP decreased thyroid cancer risk at age ≤45 years. Rs4649295 was associated with lower susceptibility to thyroid cancer at age ≤45 years. An association was observed between rs6424270 and rs12129938 with decreased susceptibility to thyroid cancer in women. Rs10910660 was related to thyroid cancer risk in men. The combination of rs6424270, rs10910660, rs12129938 and rs4649295 was the best model to predict thyroid cancer. Conclusion: This study suggests that PCNXL2 polymorphisms are risk factors for thyroid cancer in the Chinese population.

Rare germline variants in DNA repair-related genes are accountable for papillary thyroid cancer susceptibility

BACKGROUND

Understanding the molecular mechanisms underlying papillary thyroid cancer (PTC) proved to be vital not only for diagnostic purposes but also for tailored treatments. Despite the strong evidence of heritability, only a small subset of alterations has been implicated in PTC pathogenesis. To this reason, we used targeted next-generation sequencing (NGS) to identify candidate variants implicated in PTC pathogenesis, progression, and invasiveness.

METHODS

A total of 42 primary PTC tissues were investigated using a targeted next-generation sequencing (NGS) panel enlisting 47 genes involved in DNA repair and tumor progression.

RESULTS

We identified 57 point mutations in 78.5% of samples (n = 32). Thirty-two somatic mutations were identified exclusively in known thyroid cancer genes (BRAF, KRAS, NRAS, and TERT). Unpredictably, 45% of the all identified mutations (n = 25) resulted to be germline, most affecting DNA repair genes. Interestingly, none of the latter variants was in the main population databases. Following ACMG classification, 20% of pathogenic/likely pathogenic and 68% of variant of unknown significance were identified.

CONCLUSIONS

Overall, our results support the hypothesis that rare germline variants in DNA repair genes are accountable for PTC susceptibility. More data, including the segregation analysis in affected families, should be collected before definitely annotate these alterations and to establish their potential prognostic and treatment implications.

Correlation of the Expression of BRAF V600E Mutation With Various Phenotypic Expressions of Thyroid Neoplasms

Aims We aimed to assess the incidence of the BRAF V600E mutation in thyroid neoplasms at a tertiary care center and its association with various phenotypic features. Methods and material We included all cases diagnosed as thyroid neoplasm in the past decade at the Department of Pathology of our institute and obtained their clinical details from the medical records department of the institute after obtaining permission from the authorities and due International Human Epigenome Consortium clearance. We included data on age, sex, clinical presentation, hormone status, and T and N status of the malignant neoplasms. Hematoxylin and eosin (H&E) slides of all cases were evaluated for the type of neoplasm, nuclear features, invasion into the capsule and vascular spaces, extrathyroidal extension, lymph node metastases, mitoses, necrosis, and presence/absence of amyloid. Paraffin blocks of sections with high tumor density and less normal tissue were chosen for evaluation after H&E staining. The slides showing tumors with large areas of hemorrhage, cystic change, or necrosis were excluded. Two primers were used to amplify a 339-bp fragment containing the V600E mutation in exon 15 of BRAF. Tissues were prepared from formalin-fixed paraffin-embedded (FFPE) blocks, and DNA was isolated using a standard protocol BRAF NF and BRAF NR Primer Standardized Protocol For FFPE Tissue DNA. Percentages and tables have been used for data presentation. Results Among 47 identified cases, 14 were positive for the BRAF V600E mutation and had papillary carcinoma (n = 9) or follicular neoplasms (n = 5; follicular adenoma, n = 3; follicular carcinoma, n = 2). In the BRAF-positive papillary carcinomas, five cases were aged 20-30 years, eight were female, eight (88.88%) were euthyroid, and one was hypothyroid. Furthermore, 55.55% (5/9 cases) of BRAF-positive cases were stage I, 33.3% (3/9 cases) were stage II, and 0.02% (1/9 cases) were stage III. Conclusions In our cohort, 31% of cases of papillary thyroid carcinoma (PTC) and 18.72% of follicular neoplasms expressed the BRAF V600E mutation. BRAF V600E mutation-positive papillary thyroid carcinomas consistently showed all characteristic nuclear features, such as nuclear crowding, overlapping, and grooves. Considering the greater prevalence in the younger age group, the importance of mutation surveillance in PTCs for a total thyroidectomy may be warranted in mutation-positive patients.

Hypoparathyroidism in Pregnancy and Lactation: Current Approach to Diagnosis and Management

Background: Hypoparathyroidism is an uncommon endocrine disorder. During pregnancy, multiple changes occur in the calcium-regulating hormones, which may affect the requirements of calcium and active vitamin D during pregnancy in patients with hypoparathyroidism. Close monitoring of serum calcium during pregnancy and lactation is ideal in order to optimize maternal and fetal outcomes. In this review, we describe calcium homeostasis during pregnancy in euparathyroid individuals and also review the diagnosis and management of hypoparathyroidism during pregnancy and lactation. Methods: We searched the MEDLINE, CINAHL, EMBASE, and Google scholar databases from 1 January 1990 to 31 December 2020. Case reports, case series, book chapters, and clinical guidelines were included in this review. Conclusions: During pregnancy, rises in 1,25-dihydroxyvitamin D (1,25-(OH)2-D3) and PTH-related peptide result in suppression of PTH and enhanced calcium absorption from the bowel. In individuals with hypoparathyroidism, the requirements for calcium and active vitamin D may decrease. Close monitoring of serum calcium is advised in women with hypoparathyroidism with adjustment of the doses of calcium and active vitamin D to ensure that serum calcium is maintained in the low-normal to mid-normal reference range. Hyper- and hypocalcemia should be avoided in order to reduce the maternal and fetal complications of hypoparathyroidism during pregnancy and lactation. Standard of care therapy consisting of elemental calcium, active vitamin D, and vitamin D is safe during pregnancy.

Nature and outcome of malignant goiter: a revisit

Introduction

the aim of this retrospective study is to review patients with malignant goiter, as regards their nature, demographic characterization, clinical presentation and preoperative histopathological data.

Methods

the study focused on a period of 4 years from December 2015 to January 2019. Patients´ demographic data, clinical presentation, Intra-operative findings, Pre and postoperative histopathological staging and grading were all recorded. Postoperative follow up whether early or late were also included.

Results

a total of 100% (n = 65) patients underwent surgery. The female to male ratio was found to be 5:1 (48 females and 17 males). Solitary nodule was the main clinical presentation in 80% (n = 52) of cases while 20% (n = 13) were multinodular swellings. Papillary carcinoma was recorded in 80% (n = 52) of patients while in 15.4% (n =10) of patients were having follicular carcinoma. The remaining 4.6% (n = 3) suffered of lymphoma; no medullary or anaplastic tumors were reported.

Conclusion

thyroid cancer is the most commonly encountered endocrinal malignancy at our institute. Fine Needle Aspiration Cytology (FNAC) showed a high percentage of reliability in diagnosing thyroid cancer among our series. It is recommended to adapt this technique in initial screening of goiter patients in our local setting.

Thyroid Cancer and Circadian Clock Disruption

Thyroid cancer (TC) represents the most common malignancy of the endocrine system, with an increased incidence across continents attributable to both improvement of diagnostic procedures and environmental factors. Among the modifiable risk factors, insulin resistance might influence the development of TC. A relationship between circadian clock machinery disfunction and TC has recently been proposed. The circadian clock machinery comprises a set of rhythmically expressed genes responsible for circadian rhythms. Perturbation of this system contributes to the development of pathological states such as cancer. Several clock genes have been found deregulated upon thyroid nodule malignant transformation. The molecular mechanisms linking circadian clock disruption and TC are still unknown but could include insulin resistance. Circadian misalignment occurring during shift work, jet lag, high fat food intake, is associated with increased insulin resistance. This metabolic alteration, in turn, is associated with a well-known risk factor for TC i.e., hyperthyrotropinemia, which could also be induced by sleep disturbances. In this review, we describe the mechanisms controlling the circadian clock function and its involvement in the cell cycle, stemness and cancer. Moreover, we discuss the evidence supporting the link between circadian clockwork disruption and TC development/progression, highlighting its potential implications for TC prevention, diagnosis and therapy.

Downregulation of miR‑193a‑3p via targeting cyclin D1 in thyroid cancer

Thyroid cancer (TC) is a frequently occurring malignant tumor with a rising steadily incidence. microRNA (miRNA/miR)‑193a‑3p is an miRNA that is associated with tumors, playing a crucial role in the genesis and progression of various cancers. However, the expression levels of miR‑193a‑3p and its molecular mechanisms in TC remain to be elucidated. The present study aimed to probe the expression of miR‑193a‑3p and its clinical significance in TC, including its underlying molecular mechanisms. Microarray and RNA sequencing data gathered from three major databases, specifically Gene Expression Omnibus (GEO), ArrayExpress and The Cancer Genome Atlas (TCGA) databases, and the relevant data from the literature were used to examine miR‑193a‑3p expression. Meta‑analysis was also conducted to evaluate the association between clinicopathological parameters and miR‑193a‑3p in 510 TC and 59 normal samples from the TCGA database. miRWalk 3.0, and the TCGA and GEO databases were used to predict the candidate target genes of miR‑193a‑3p. Gene Ontology, Kyoto Encyclopedia of Genes and Genomes and protein‑protein interaction network enrichment analyses were conducted by using the predicted candidate target genes to investigate the underlying carcinogenic mechanisms. A dual luciferase assay was performed to validate the targeting regulatory association between the most important hub gene cyclin D1 (CCND1) and miR‑193a‑3p. miR‑193a‑3p expression was considerably downregulated in TC compared with in the non‑cancer controls (P<0.001). The area under the curve of the summary receiver operating characteristic was 0.80. Downregulation of miR‑193a‑3p was also significantly associated with age, sex and metastasis (P=0.020, 0.044 and 0.048, respectively). Bioinformatics analysis indicated that a low miR‑193a‑3p expression may augment CCND1 expression to affect the biological processes of TC. In addition, CCND1, as a straightforward target, was validated through a dual luciferase assay. miR‑193a‑3p and CCND1 may serve as prognostic biomarkers of TC. Finally, miR‑193a‑3p may possess a crucial role in the genesis and progression of TC by altering the CCND1 expression.

Novel RET Proto-oncogene variants identified in Turkish patients with thyroid carcinoma

Thyroid cancer is one of the few malignancies whose incidence is increasing in the last decades. Advances in understanding the molecular mechanisms lead to provide opportunity for prevention, effective early identification and targeted therapies for management. A total of 63 patients with participated in this study Genomic DNA samples were obtained from the samples formalin- embedded tissue and peripheral blood. Following polymerase chain reaction amplification of the 6 RET key exons (10, 11, 13, 14, 15, and 16) were applied and PCR products were subjected to next generation DNA sequencing (ABI 3730). Results revealed that; genotype frequencies were for rs1800961 (G > T) , GG 6 (%9.5), GT 17 (%27) TT40 (%63.5) for rs2472732 (G > A), GG31 (%49.2) GA29 (%46) AA3 (%4.8,) for rs1799939, (G > A) GG42 (%66.7) GA19 (%30.2) AA2 (%3.2), for rs1800962, (C > T) CC54 (%85.7) CT9 (%14.3), for rs1800863 (C > G), CC39 (%61.9) CG22 (%34.9) GG2 (%3.2), for rs3026272 (C > G) CC 13 (%20.6) CG 50 (%79.4). Additionally 15 potential novel genetic variants were identified in these key exons. Detailed information was given both known and new detected variants in supplementary table. Genetic variants distribution frequencies and new variants represented in Turkish thyroid cancer patients for RET proto-oncogene and that results would provide contribution to the literature.

Clinicopathological characterization and prognostic implication of FOXP3 and CK19 expression in papillary thyroid carcinoma and concomitant Hashimoto's thyroiditis

Papillary thyroid carcinoma (PTC) is considered the most prevalent thyroid malignancy. The association between Hashimoto's thyroiditis (HT) and PTC is still unclear. We aimed to examine the clinicopathological impact of immunohistochemical staining of FOXP3 and Cytokeratin 19 in PTC and concomitant HT and their correlation with patients' outcome and survival. Eighty thyroid biopsies obtained from patients with PTC were immunostained by FOXP3 and CK19.The patients were treated by radioactive iodine (I131) and followed up. FOXP3 and CK19 expression were detected in 45% and 80% studied cases of PTC respectively. 16.7% of PTC with associated HT showed FOXP3+ lymphocytes in lymphocytic infiltrate of HT, while most of PTC associated HT express cytoplasmic CK19 positive Hurtle cells. FOXP3 was more expressed in PTC female patients more than 45 years with higher stage, lymph node, and distant metastasis, extracapsular extension, number of I131doses, and cumulative radioiodine doses with a highly statistically significant difference (p < 0.001). The relation was significant between CK19 immunostaining as regard 10-year Overall Survival and death (p value = 0.027 and 0.036, respectively). HT represents a step in the process of autoimmune inflammatory disease ending by the evolution of PTC with better prognosis, therefore appropriate follow up of these cases is needed. FOXP3 tends to be more expressed in PTC cases with worse prognostic variables and is predictable to become a recent prognostic and targeted therapy for PTC. There was a significant relation between CK19 immunostaining and 10 year overall survival.

Prevalence and Risk of Metastatic Thyroid Cancers and Management Outcomes: A National Perspective

OBJECTIVES

Examine the prevalence and risk of metastasis in thyroid cancers and management outcomes.

STUDY DESIGN

Retrospective analysis of the National Cancer Database, 2004-2014.

METHODS

The study population included adult (≥ 18 years) patients with thyroid cancer. Analysis included multivariate logistic regression and Cox hazard ratio modeling.

RESULTS

A total of 152,979 patients were included. Distant metastasis was reported in 1,867 (1.22%) patients. The distribution of metastatic cases based on pathology and tumor size were as follows in descending order: papillary thyroid carcinoma (PTC) 1 to 4 cm (30.53%), PTC > 4 cm (19.34%), undifferentiated (UTC) > 4 cm (14.14%), PTC < 1 cm (8.46%), follicular thyroid carcinoma (FTC) > 4 cm (7.28%), FTC 1 to 4 cm (5.52%), medullary thyroid cancer (MTC) ≤ 4 cm (3.96%), MTC > 4 cm (3.91%), UTC ≤ 4 cm (3.32%), Hürthle (HCC ) > 4 cm (2.09%), and HCC 1 to 4 cm (1.45%). Significant predictors of distant metastasis, while controlling for tumor pathology and size, included older age, male gender, non-White minorities, presence of multiple comorbidities, minimal, gross extrathyroidal extension (ETE), lymphovascular invasion (LVI), and concomitant central and lateral lymph node metastasis (LNM) (P < .05 each). The risk of distant metastasis in the absence of nodal metastasis, ETE, and LVI was highest for FTC > 4 cm.

CONCLUSION

Although the risk of metastasis in well-differentiated thyroid carcinoma (WDTC) is low, the prevalence of metastatic thyroid cancer is highest in WDTC population because it is the most common type of thyroid cancer. Certain pathological features, including minimal ETE and central LNM, are associated with a higher prevalence of metastatic disease.

LEVEL OF EVIDENCE

NA Laryngoscope, 131:237-244, 2021.

Anaplastic thyroid cancer: How far can we go?

Globally, thyroid cancer accounts for 2 % of all cancer diagnoses, and can be classified as well-differentiated or undifferentiated. Currently, differentiated thyroid carcinomas have good prognoses, and can be treated with a combination of therapies, including surgical thyroidectomy, radioactive iodine therapy and hormone-based therapy. On the other hand, anaplastic thyroid carcinoma, a subtype of undifferentiated thyroid carcinoma characterized by the loss of thyroid-like phenotype and function, does not respond to either radioactive iodine or hormone therapies. In most cases, anaplastic thyroid carcinomas are diagnosed in later stages of the disease, deeming them inoperable, and showing poor response rates to systemic chemotherapy. Recently, treatment courses using multiple-target agents are being explored and clinical trials have shown very promising results, such as overall survival rates, progression-free survival and tumor shrinkage. This review is focused on thyroid carcinomas, with particular focus on anaplastic thyroid carcinoma, exploring its undifferentiated nature. Special interest will be given to the treatment approaches currently available and respective obstacles or drawbacks. Our purpose is to contribute to understand why this malignancy presents low responsiveness to current treatments, while overviewing novel therapies and clinical trials.

FOXE1 regulates migration and invasion in thyroid cancer cells and targets ZEB1

FOXE1 is a thyroid-specific transcription factor essential for thyroid gland development and maintenance of the differentiated state. Interestingly, a strong association has been recently described between FOXE1 expression and susceptibility to thyroid cancer, but little is known about the mechanisms underlying FOXE1-induced thyroid tumorigenesis. Here, we used a panel of human thyroid cancer-derived cell lines covering the spectrum of thyroid cancer phenotypes to examine FOXE1 expression and to test for correlations between FOXE1 expression, the allele frequency of two SNPs and a length polymorphism in or near the FOXE1 locus associated with cancer susceptibility, and the migration ability of thyroid cancer cell lines. Results showed that FOXE1 expression correlated with differentiation status according to histological sub-type, but not with SNP genotype or cell migration ability. However, loss-and-gain-of-function experiments revealed that FOXE1 modulates cell migration, suggesting a role in epithelial-to-mesenchymal transition (EMT). Our previous genome-wide expression analysis identified Zeb1, a major EMT inducer, as a putative Foxe1 target gene. Indeed, gene silencing of FOXE1 decreased ZEB1 expression, whereas its overexpression increased ZEB1 transcriptional activity. FOXE1 was found to directly interact with the ZEB1 promoter. Lastly, ZEB1 silencing decreased the ability of thyroid tumoral cells to migrate and invade, pointing to its importance in thyroid tumor mestastases. In conclusion, we have identified ZEB1 as a bona fide target of FOXE1 in thyroid cancer cells, which provides new insights into the role of FOXE1 in regulating cell migration and invasion in thyroid cancer.

Hypermethylated RASSF1 and SLC5A8 promoters alongside BRAFV600E mutation as biomarkers for papillary thyroid carcinoma

Circulating cell-free DNA (cfDNA) has been considered as a diagnostic source to track genetic and epigenetic alterations in cancer. We aimed to study mutation in addition to the methylation status in the promoter regions of RASSF1 and SLC5A8 genes in tissues and circulating free DNA samples of patients affected with papillary thyroid carcinoma (PTC) and thyroid nodules as controls. BRAF^V600E mutation was studied by ARMS-scorpion real-time polymerase chain reaction method in 57 PTC and 45 thyroid nodule cases. Methylation status of RASSF1 and SLC5A8 promoter regions was analyzed by methylation-specific high-resolution melting curve analysis. BRAF^V600E mutation was found in 39 (68.4%) out of 57 PTC tissue samples, while in 33 (49.1%) cases of cfDNA, this mutation was detected. The frequency of BRAF^V600E mutation in cfDNA was significantly different between metastatic and nonmetastatic PTC cases (22 of 33 PTC cases vs. 5 of 34 thyroid nodule samples). Methylation levels of three promoter regions of SLC5A8 and proximal promoter region of RASSF1 was significantly different between PTC and thyroid nodule cases in both cfDNA and tissue DNA. In addition, the methylation status of these two genes in tissue DNA was reflected in methylation status observed in cfDNA. This study confirmed that BRAF^V600E mutation is better for discrimination between papillary thyroid carcinoma and thyroid nodules. On the other hand, hypermethylation in the more proximal promoter regions to RASSF1 and SLC5A8 genes showed higher sensitivity and more acceptable specificity for this discrimination.

Molecular Alterations in Thyroid Cancer: From Bench to Clinical Practice

Thyroid cancer comprises different clinical and histological entities. Whereas differentiated (DTCs) malignancies are sensitive to radioiodine therapy, anaplastic (ATCs) and medullary (MTCs) tumors do not uptake radioactive iodine and display aggressive features associated with a poor prognosis. Moreover, in a majority of DTCs, disease evolution leads to the progressive loss of iodine sensitivity. Hence, iodine-refractory DTCs, along with ATCs and MTCs, require alternative treatments reflective of their different tumor biology. In the last decade, the molecular mechanisms promoting thyroid cancer development and progression have been extensively studied. This has led to a better understanding of the genomic landscape, displayed by thyroid malignancies, and to the identification of novel therapeutic targets. Indeed, several pharmacological compounds have been developed for iodine-refractory tumors, with four multi-target tyrosine kinase inhibitors already available for DTCs (sorafenib and lenvatinib) and MTCs (cabozantib and vandetanib), and a plethora of drugs currently being evaluated in clinical trials. In this review, we will describe the genomic alterations and biological processes intertwined with thyroid cancer development, also providing a thorough overview of targeted drugs already tested or under investigation for these tumors. Furthermore, given the existing preclinical evidence, we will briefly discuss the potential role of immunotherapy as an additional therapeutic strategy for the treatment of thyroid cancer.

Clonal analysis of early-stage bilateral papillary thyroid cancer identifies field cancerization

INTRODUCTION

Bilaterality is a newly identified indicator for aggressive tumor behavior and poor outcome in papillary thyroid cancer. However, the clonal origin of these bilateral tumors remains unclear.

METHODS

Here we analyzed 28 pairs of early-stage papillary thyroid cancers (stage I-II without extra-thyroidal extension, lymph node metastasis or distant metastasis) that underwent surgery at First Affiliated Hospital of Zhejiang University School of Medicine (Hangzhou, China). Genomic DNA was extracted from paraffin-embedded tissues after microdissection and analyzed for BRAF mutation and X-chromosome inactivation.

RESULTS

A total of 16 patients (16/28, 57.1%) harbored different BRAF status in bilateral tumors. Fourteen patients were available for X-chromosome inactivation assay and 10 of them achieved informative results. Bilateral tumors from four cases had distinct patterns of X-chromosome inactivation. Combining the results of X-chromosome inactivation and BRAF analysis, we demonstrated that at least 64.3% (18/28) cases harbored discordant X-chromosome inactivation or BRAF status, indicating their independent clonal origin in bilateral tumors.

CONCLUSIONS

The present study confirms "field cancerization" in early-stage bilateral thyroid cancers, suggesting that these subtype papillary thyroid cancers should be treated as independent and localized tumors.

Primary Leiomyosarcoma of the Thyroid Gland - A Rare Malignancy

Primary leiomyosarcoma (LMS) of thyroid is rare malignant neoplasm usually seen in elderly patients. These tumours are characterised by a rapidly growing mass in the neck, difficult to diagnose preoperatively and are highly aggressive with high recurrence rates in spite of radical surgery, chemotherapy and radiotherapy. We herein report a case of 50-year-old female with a rapidly growing painless mass in the neck. Total thyroidectomy with bilateral neck node clearance was done. Histology and Immunohistochemistry revealed primary LMS of thyroid gland. Within 1 month of radical surgery she developed local recurrence. Diagnosis of primary LMS is difficult and immunohistochemistry is necessary to differentiate it from other malignancies of the thyroid. Primary LMS remains a life-threatening tumour and more effective treatment are needed to improve outcome.

Diagnostic pitfalls and therapeutic outcomes of the macrofollicular variant of papillary thyroid carcinoma

Background

The macrofollicular variant of papillary thyroid cancer (MFVPTC) is a rare histological variant of papillary thyroid cancer (PTC), with only 71 cases reported through 2014. This study analyzed the clinical, preoperative thyroid ultrasonography (US), and fine needle aspiration cytology (FNAC) features; and therapeutic outcomes of 11 patients with MFVPTC.

Methods

The records of 393 patients with histologically diagnosed follicular variant of papillary thyroid carcinoma (FVPTC), including 11 with MFVPTC, were retrospectively reviewed. Preoperative thyroid US findings, clinical presentation, treatment outcomes, and survival rates were analyzed.

Result

Mean tumor size was significantly greater in patients with MFVPTC than that in those with FVPTC (4.2 ± 2.1 cm vs. 2.9 ± 1.7 cm; p = 0.016). No patient with MFVPTC had lymph node involvement, but one had a micrometastasis to the lung, which responded well to therapeutic radioiodine. All MFVPTC lesions were isoechoic on US. Eight nodules had calcifications and eight had irregular margins. FNAC showed that these tumors had low cellularity, absence or focal presence of enlarged clear nuclei, and subtle or focal nuclear features of PTC. Cells were, arranged in microfollicular pattern, with abundant colloid background. Multifocal PTCs were detected in the opposite lobe of two patients. All 11 patients with MFVPTC had excellent outcomes. No patient experienced recurrence, and survival rates were high.

Conclusions

Malignant US criteria combined with FNAC features have a low preoperative diagnostic rate for MFVPTC. Surgery is recommended for patients with thyroid nodules larger than 4 cm and those with subtle and focal atypical nuclei in FNAC.

Surgical management of follicular thyroid carcinoma in children and adolescents: A study of 30 cases

BACKGROUND/PURPOSE

The purpose of the study is to describe the anatomoclinical, diagnostic, therapeutic and prognostic aspects of pediatric follicular thyroid carcinoma (FTC) in order to choose the best therapeutic strategy.

METHODS

Our study includes patients ≤18 years old surgically treated for FTC in four Italian Pediatric Surgery Centers from January 2000 to March 2017. The collected data were compared with those of 132 patients matched for age with a histological diagnosis of papillary thyroid carcinoma (PTC) surgically treated in the same institutions during the same period and with the data of patients diagnosed with FTC found in the literature; p-values <0.05 were considered significant.

RESULTS

21 (70%) of the 30 patients with a histological diagnosis of FTC underwent hemithyroidectomy while 9 (30%) underwent total thyroidectomy. 11 (55%) out of 21 patients were subjected to a completion of thyroidectomy. All patients are alive (OS = 100%) without recurrence or relapse of the disease. Compared with PTC, FTC is significant for capsule infiltration (p < 0.0001), vascular invasion (p = 0.0014) and T-stage T3-T4 (p = 0.013). However, multifocality (p < 0.001), extrathyroid extension (p < 0.0001) and lymph node metastasis (p < 0.0001) are more evident in PTC.

CONCLUSION

The conservative approach seems to be a valid surgical treatment for pediatric patients diagnosed with MI-FTC. For patients with wide vascular invasion and/or a tumor >4 cm, especially with high after-surgery Tg rate, a completion of thyroidectomy is recommended. In patients with multifocal neoplasia, and/or tumor size ≥4 cm, and/or extrathyroid extension, and/or lymph node metastasis, and/or distant metastasis, total thyroidectomy followed by radioiodine therapy is generally indicated.

LEVELS OF EVIDENCE

II.

Association between hTERT Polymorphisms and Female Papillary Thyroid Carcinoma

BACKGROUND

A previous genome-wide association study showed that hTERT rs10069690 and rs2736100 polymorphisms were associated with thyroid cancer risk.

OBJECTIVE

This study further investigated the association between increased risk and clinicopathologic characteristics for Papillary Thyroid Carcinoma (PTC) and hTERT polymorphisms rs10069690 or rs2736100 in a Chinese female population.

METHODS

The hTERT genotypes of 276 PTC patients and 345 healthy subjects were determined with regard to SNPs rs10069690 and rs2736100. The association between these SNPs and the risk of PTC and clinicopathologic characteristics was investigated by logistic regression.

RESULTS

We found a significant difference between PTC and rs10069690 (Odds Ratio (OR) = 1.515; P = 0.005), but not between PTC and rs2736100. When the analysis was limited to females, rs10069690 and rs2736100 were both associated with increased risk for PTC in female individuals (OR = 1.647, P = 0.007; OR = 1.339, P = 0.041, respectively). Further haplotype analysis revealed a stimulative effect of haplotypes TC and CA of TERT rs10069690-rs2736100, which increased risk for PTC in female individuals (OR = 1.579, P = 0.014; OR = 0.726, P = 0.025, respectively). Furthermore, the heterozygote A/C of rs2736100 showed significant difference for age (OR = 0.514, P = 0.047).

CONCLUSION

Our finding suggests that hTERT polymorphisms rs10069690 and rs2736100 are associated with increased risk for PTC in Chinese female population and rs2736100 may be related to age. Consistent with US20170360914 and US20170232075, they are expected to be a potential molecular target for anti-cancer therapy.

The Emerging Role of Insulin Receptor Isoforms in Thyroid Cancer: Clinical Implications and New Perspectives

Thyroid cancer (TC) is the most common endocrine tumor. Although the majority of TCs show good prognoses, a minor proportion are aggressive and refractory to conventional therapies. So far, the molecular mechanisms underlying TC pathogenesis are incompletely understood. Evidence suggests that TC cells and their precursors are responsive to insulin and insulin-like growth factors (IGFs), and often overexpress receptors for insulin (IR) and IGF-1 (IGF-1R). IR exists in two isoforms, namely IR-A and IR-B. The first binds insulin and IGF-2, unlike IR-B, which only binds insulin. IR-A is preferentially expressed in prenatal life and contributes to development through IGF-2 action. Aggressive TC overexpresses IR-A, IGF-2, and IGF-1R. The over-activation of IR-A/IGF-2 loop in TC is associated with stem-like features and refractoriness to some targeted therapies. Importantly, both IR isoforms crosstalk with IGF-1R, giving rise to the formation of hybrids receptors (HR-A or HR-B). Other interactions have been demonstrated with other molecules such as the non-integrin collagen receptor, discoidin domain receptor 1 (DDR1), and the receptor for the hepatocyte growth factor (HGF), Met. These functional networks provide mechanisms for IR signaling diversification, which may also exert a role in TC stem cell biology, thereby contributing to TC initiation and progression. This review focuses on the molecular mechanisms by which deregulated IR isoforms and their crosstalk with other molecules and signaling pathways in TC cells and their precursors may contribute to thyroid carcinogenesis, progression, and resistance to conventional treatments. We also highlight how targeting these alterations starting from TC progenitors cells may represent new therapeutic strategies to improve the clinical management of advanced TCs.

A Rare Case of Heterozygous Gain of Function Thyrotropin Receptor Mutation Associated with Development of Thyroid Follicular Carcinoma

Activating mutations in thyrotropin receptor (TSHR) have been previously described in the context of nonautoimmune hyperthyroidism and thyroid adenomas. We describe, for the first time, a mutation in TSHR contributing to follicular thyroid carcinoma (FTC) in an adolescent. A 12-year-old girl presented with a right-sided neck swelling, increasing in size over the previous four weeks. Clinical examination revealed a firm, nontender thyroid nodule. Ultrasound scan of the thyroid showed a heterogeneous highly vascular mass. Thyroid function tests showed suppressed TSH [<0.03mU/L], normal FT4 [10.1pmol/L, 9-19], and raised FT3 [9.1pmol/L, 3.6-6.4]. Thyroid [TPO and TRAB] antibodies were negative. A right hemithyroidectomy was performed and the histology of the sample revealed follicular carcinoma with mild to moderate nuclear pleomorphism and evidence of capsular and vascular invasion (pT1b). Sanger sequencing of DNA extracted from the tumour tissue revealed a missense somatic mutation (c.1703T>C, p.Ile568Thr) in TSHR. Papillary thyroid carcinomas constitute the most common thyroid malignancy in childhood, while FTC is rare. FTC due to TSHR mutation suggests an underlying, yet to be explored, molecular pathway leading to the development of malignancy. The case is also unique in that the clinical presentation of FTC as a toxic thyroid nodule has not been previously reported in children.

The diagnostic value of TROP-2, SLP-2 and CD56 expression in papillary thyroid carcinoma

OBJECTIVE

The study aimed to explore some novel diagnostic biomarkers for papillary thyroid carcinoma (PTC) by identifying the different expression of TROP-2, SLP-2 and CD56 in benign and malignant thyroid lesions.

METHODS

We evaluated the mRNA expressions of TROP-2 and SLP-2 in fine needle aspirates (FNAs) which contained 10 PTCs and 10 benign follicular adenomas (FAs) using quantitative real-time PCR (qRT-PCR). Immunohistochemical (IHC) staining of TROP-2, SLP-2 and CD56 was also performed on postoperative samples of 30 PTCs and 29 FAs. Membranous or cytoplasmic staining in > 10% of cells was considered as positive. Diagnostic sensitivity, specificity, positive predictive value, negative predictive value (NPV) and diagnostic accuracy of these three biomarkers were carried out. We further analyzed the associations between the clinical features and the expressions of markers in PTCs.

RESULTS

The mRNA expressions of both TROP-2 and SLP-2 were increased substantially in PTCs in comparison with those in FAs (P < 0.05). Similarly, IHC for these two proteins demonstrated higher positive staining in PTCs than in FAs (96.5% vs. 12.5% for TROP-2, 83.3% vs. 20.7% for SLP-2, P < 0.05). Conversely, CD56 expression was lost with 86.7% of PTCs. In identifying malignancy, TROP-2 was the most sensitive marker and CD56 was the most specific one. When the markers were combined, the sensitivity and NPV increased to 100% and had better diagnostic accuracy. However, no association was found between biomarker expressions and clinicopathological factors in PTCs.

CONCLUSIONS

We found that TROP-2, SLP-2 and CD56 were effective diagnostic markers for PTC, especially when they were combined to use.

Restoration of p53 using the novel MDM2-p53 antagonist APG115 suppresses dedifferentiated papillary thyroid cancer cells

Dedifferentiated papillary thyroid cancer (DePTC) is characterized by aggressive growth, recurrence, distant metastasis, and resistance to radioactive iodine (RAI) therapy. DePTC is also accompanied by poor prognosis and high early-mortality. Nevertheless, most DePTC cells show intact p53 downstream functionality. In cells with wild-type p53, the murine double minute2 (MDM2) protein interacts with p53 and abrogates its activity. Inhibition of the MDM2-p53 interaction restores p53 activity and leads to cell cycle arrest and apoptosis. Restoring p53 function by inhibiting its interaction with p53 suppressors such as MDM2 is thus a promising therapeutic strategy for the treatment of DePTC. The novel MDM2-p53 interaction antagonist APG115 is an analogue of SAR405838, and is being tested in a phase I clinical trial. In this study, we evaluated the efficacy of APG115 as a single-agent to treat DePTC. APG115 diminished the viability of p53 wild-type DePTC cells and induced cell cycle arrest and apoptosis. In a human xenograft mouse model, APG115 elicited robust tumor regression and cell apoptosis. These data demonstrate that further research is warranted to determine whether APG115 can be used to effectively treat DePTC patients.

Expression of Hypoxia-Associated Protein HIF-1α in Follicular Thyroid Cancer is Associated with Distant Metastasis

Follicular thyroid carcinomas (FTCs) are the second most common malignant neoplasia of the thyroid and in general its prognosis is quite favorable. However, the occurrence of metastases or non-responsiveness to radioiodine therapy worsens the prognosis considerably. We evaluated immunohistochemically the expression of hypoxia-associated proteins by hypoxia-induced factor 1α (HIF-1α), the stroma-remodeling marker Tenascin C, as well as markers for the epithelial-mesenchymal transition (EMT), namely E-cadherin and slug in a series of 59 sporadic FTCs. In addition, various clinicopathologic parameters were assessed like TNM-staging, age, tumor size as well as tumor characteristics like desmoplasia, necrosis, and calcification. Overexpression of HIF-1α was seen in 29 of 59 tumors (49.2%) including 21 (35.6%) FTC with strong expression of tumor cell groups. HIF-1α correlated significantly with metastasis (p < 0.001; Mann-Whitney U test), degree of desmoplasia (p = 0.042, Kruskal-Wallis test), tenascin C expression (p = 0.042, Kruskal-Wallis test), calcification (p < 0.025, Kruskal-Wallis test), necrosis (p = 0.002), age (p = 0.011, Kruskal-Wallis test) and tumor stage UICC (p = 0.022, Kruskal-Wallis test). Furthermore, metastasis was associated with the degree of desmoplasia (p = 0.014; Fisher's exact test), calcification (p = 0.008, Fisher's exact test), necrosis (p = 0.042, Fisher's exact test), tumor size (p = 0.015, Mann-Whitney U test), and age (p = 0.001, Mann-Whitney U test). In a Cox proportional hazards model, only metastasis remained as an independent risk factor for overall survival (hazard rate: 10.2 [95% CI, 02.19 to 47.26]; p = 0.003). Our data suggest that HIF-1α plays a critical role in the remodeling of the extracellular matrix as well as metastasizing process of follicular thyroid carcinoma and targeting hypoxia-associated and -regulated proteins may be considered as potential targets for personalized medicine.

Differentiation of the Follicular Variant of Papillary Thyroid Carcinoma From Classic Papillary Thyroid Carcinoma: An Ultrasound Analysis and Complement to Fine-Needle Aspiration Cytology

OBJECTIVES

It is difficult to establish a diagnosis of the follicular variant of papillary thyroid carcinoma (PTC) using fine-needle aspiration cytology (FNAC). Preoperative features on ultrasound (US) imaging are different between follicular PTC and classic PTC. This study developed a risk score system to differentiate follicular PTC from classic PTC and to correlate the risk score of follicular PTC with its FNAC categories and pathologic features.

METHODS

The US features, FNAC results, and pathologic reports of 156 follicular PTC nodules and 152 classic PTC nodules from 296 patients with PTC along with their clinical characteristics were reviewed retrospectively. A risk score system based on US features was developed by multivariate logistic regression to differentiate classic PTC from follicular PTC nodules. The risk scores were then correlated with the FNAC category and pathologic features of the nodules.

RESULTS

The US risk score (5 × echogenicity + 3 × calcifications + 3 × marginal regularity) had an area under the receiver operating characteristic curve of 0.85 and a cutoff value of 8.0, with specificity of 87% and sensitivity of 69% for predicting a classic PTC nodule. The follicular PTC nodules with low Bethesda categorization (I-III) had a median US risk score of 6 (range, 0-11), which was higher than that of nodules with high categorization (IV-VI; median, 3; range, 0-11).

CONCLUSIONS

The US risk score may be useful in differentiating classic PTC from follicular PTC and complementary to FNAC in identifying follicular PTC.

rs965513 polymorphism as a common risk marker is associated with papillary thyroid cancer

Papillary thyroid cancer (PTC) is the most common type of thyroid cancer. With the rapid development of genome-wide association studies (GWAS), many genome variants associated with susceptibility to PTC have been identified, including the single nucleotide polymorphism rs965513 (9q22.33) near FOXE1. To evaluate the association between rs965513 and PTC in different ethnicities and countries, we conducted a meta-analysis using relatively large-scale samples from 23 studies (N = 163,136; 20,736 cases and 142,400 controls) by searching the PubMed and Google Scholar databases. Significant heterogeneity caused by different populations among the selected studies was observed. The A allele of rs965513 polymorphism was shown to be highly associated with risk of thyroid cancer, with odds ratios of 1.58 (95% CI 1.32–1.90) in all populations, 1.65 (95% CI 1.31–2.07)) in Caucasian populations and 1.49 in Asian populations. Compared to the dominant and recessive models, we observed the highest odds ratio (OR = 2.80, 95% CI 2.12–3.69) in the homozygous model. These results revealed that the rs965513 polymorphism is a risk factor for thyroid cancer

Prognostic implication of BRAF and TERT promoter mutation combination in papillary thyroid carcinoma-A meta-analysis

INTRODUCTION

The use of molecular markers, especially BRAF and TERT promoter mutations, for risk stratification in papillary thyroid carcinoma (PTC) is subject to continuing debate. In this study, we aimed to investigate the clinicopathological implication of each genotype when combining BRAF and TERT promoter mutations in PTCs.

METHODS

We searched four electronic databases including PubMed, Scopus, Web of Science and Virtual Health Library for relevant studies. Pooled estimates of odds ratios and corresponding 95% confidence intervals were calculated using random-effect model.

RESULTS

From 111 results, we finally included 11 studies with 3911 PTC patients for meta-analyses. Our results demonstrated that PTCs with concurrent BRAF and TERT promoter mutations were associated with increased tumour aggressiveness in comparison with PTCs harbouring BRAF or TERT promoter mutation alone. The combination of BRAF and TERT promoter mutations could classify PTCs into four distinct risk groups with decreasing aggressiveness as follows: coexisting BRAF and TERT > TERT alone=BRAF alone > no mutations.

CONCLUSION

The risk stratification of PTC based on these four genotypes can help improve the clinical management of PTCs by identifying the group of PTCs with the highest aggressiveness.

Genome-wide association and expression quantitative trait loci studies identify multiple susceptibility loci for thyroid cancer

Thyroid cancer is the most common cancer in Korea. Several susceptibility loci of differentiated thyroid cancer (DTC) were identified by previous genome-wide association studies (GWASs) in Europeans only. Here we conducted a GWAS and a replication study in Koreans using a total of 1,085 DTC cases and 8,884 controls, and validated these results using expression quantitative trait loci (eQTL) analysis and clinical phenotypes. The most robust associations were observed in the NRG1 gene (rs6996585, P=1.08 × 10-10) and this SNP was also associated with NRG1 expression in thyroid tissues. In addition, we confirmed three previously reported loci (FOXE1, NKX2-1 and DIRC3) and identified seven novel susceptibility loci (VAV3, PCNXL2, INSR, MRSB3, FHIT, SEPT11 and SLC24A6) associated with DTC. Furthermore, we identified specific variants of DTC that have different effects according to cancer type or ethnicity. Our findings provide deeper insight into the genetic contribution to thyroid cancer in different populations.

Restoration of Brain Acid Soluble Protein 1 Inhibits Proliferation and Migration of Thyroid Cancer Cells

BACKGROUND

Brain acid soluble protein 1 (BASP1) is identified as a novel potential tumor suppressor in several cancers. However, its role in thyroid cancer has not been investigated yet. In the present study, the antitumor activities of BASP1 against the growth and migration of thyroid cancer cells were evaluated.

METHODS

BASP1 expression in thyroid cancer tissues and normal tissues were examined by immunohistochemical staining and the association between its expression and prognosis was analyzed. pcDNA-BASP1 carrying full length of BASP1 cDNA was constructed to restore the expression of BASP1 in thyroid cancer cell lines (BHT-101 and KMH-2). The cell proliferation in vitro and in vivo was evaluated by WST-1 assay and xenograft tumor models, respectively. Cell cycle distribution after transfection was analyzed using flow cytometry. Cell apoptosis after transfection was examined by annexin V/propidium iodide assay. The migration was examined using transwell assay.

RESULTS

BASP1 expression was abundant in normal tissues while it is significantly decreased in cancer tissues (P = 0.000). pcDNA-BASP1 restored the expression of BASP1 and significantly inhibited the growth of BHT-101 and KMH-2 cells as well as xenograft tumors in nude mice (P = 0.000). pcDNA-BASP1 induced G1 arrest and apoptosis in BHT-101 and KMH-2 cells. In addition, pcDNA-BASP1 significantly inhibited the cell migration.

CONCLUSIONS

Downregulation of BASP1 expression may play a role in the tumorigenesis of thyroid cancer. Restoration of BASP1 expression exerted extensive antitumor activities against growth and migration of thyroid cancer cells, which suggested that BASP1 gene might act as a potential therapeutic agent for the treatment of thyroid cancer.

A genome-wide association study yields five novel thyroid cancer risk loci

The great majority of thyroid cancers are of the non-medullary type. Here we report findings from a genome-wide association study of non-medullary thyroid cancer, including in total 3,001 patients and 287,550 controls from five study groups of European descent. Our results yield five novel loci (all with Pcombined<3 × 10-8): 1q42.2 (rs12129938 in PCNXL2), 3q26.2 (rs6793295 a missense mutation in LRCC34 near TERC), 5q22.1 (rs73227498 between NREP and EPB41L4A), 10q24.33 (rs7902587 near OBFC1), and two independently associated variants at 15q22.33 (rs2289261 and rs56062135; both in SMAD3). We also confirm recently published association results from a Chinese study of a variant on 5p15.33 (rs2736100 near the TERT gene) and present a stronger association result for a moderately correlated variant (rs10069690; OR=1.20, P=3.2 × 10-7) based on our study of individuals of European ancestry. In combination, these results raise several opportunities for future studies of the pathogenesis of thyroid cancer.

A Brief Review on The Molecular Basis of Medullary Thyroid Carcinoma

Approximately 5-10% of all thyroid cancers are medullary thyroid carcinomas (MTC). MTC is mainly sporadic in nature, but 20-30% of cases are hereditary. Genetic testing for hereditary MTC is very important for the patient and his family, but the patients must be receiving appropriate genetic counseling. About 98% of patients with hereditary MTC have germline mutations in exons 10, 11, 13, 14, 15, 16 and intron 16 of the REarrangement during transfection (RET) proto-oncogene, but the etiology of the more frequent sporadic form of MTC (sMTC) is not well understood. Recently, it has been reported that apparently sporadic MTC may involve point mutations in BRAF and RAS genes, with an overall prevalence of almost 10%. Also alteration and abnormal expression of miRNA has been described in MTC. In this review, we attempted to mention some mutations and molecular changes in sporadic and hereditary MTC pathogenesis.

Quantitative assessment of preoperative serum thyrotropin level and thyroid cancer

Thyroid stimulating hormone (TSH) is the major growth factor for thyrocytes, but the pathogenic role of serum TSH in thyroid cancer (TC) is unknown. The association between TSH level and the development of thyroid cancer has been widely evaluated recently. However, the results remain conflicting. To develop an understanding of the relationship between TSH exposure and thyroid cancer, a meta-analysis of 56 studies involving 20227 thyroid cancer cases and 50003 controls with benign thyroid nodule was performed. Overall, significantly increased TSH level was observed in thyroid cancer patients compared with controls (RoM: 1.44, 95% CI: 1.32-1.56, P < 10-5). The pooled analyses also revealed that higher serum TSH level were significantly associated with the size of TC nodule and malignancy as well as lymph node metastasis. Furthermore, significantly increased THS levels were observed preferentially for papillary thyroid cancer when stratified by histological type of tumors. However, the diagnostic value of TSH level for TC might be limited. These results suggest that higher serum TSH concentration is associated with an increased risk of thyroid cancer.

Thyroid Cancer in Pediatrics

Well differentiated thyroid cancer (DTC) in children is characterized by a high rate of response to treatment and low disease-specific mortality. Treatment of children with DTC has evolved toward a greater reliance on evaluation and monitoring with serial serum thyroglobulin measurements and ultrasound examinations. Radioiodine therapy is recommended for thyroid remnant ablation in high-risk patients, treatment of demonstrated radioiodine-avid local-regional disease not amenable to surgical resection, or distant radioiodine-avid metastatic disease. Sufficient time should be given for benefits of radioiodine therapy to be realized, with follow-up monitoring. Re-treatment with radioiodine can be deferred until progression of significant disease manifests.

Molecular genetics of thyroid cancer

The pathogenesis of the development and progression of thyroid cancer (TC) is far from being clear at present. Accumulated evidence suggests that it is a complex polygenic disorder for which genetic factors play an important role in disease aetiology. Here we review the literature to report the genetic variations and alterations that have been described in the aetiology of TC. The functional effects of some mutations and single nucleotide polymorphisms on TC are validated, establishing the role of sequence variations in this cancer. However, large prospective studies are still required to evaluate the diagnostic and prognostic value of these genetic determinants in clinical practice.

Surgical Management of Familial Papillary Thyroid Microcarcinoma: A Single Institution Study of 94 Cases

BACKGROUND

Familial papillary thyroid carcinoma (familial PTC) is well known to present with aggressiveness; however, the characteristics and the prognostic outcomes of familial papillary thyroid microcarcinoma (familial micro-PTC) are not well established. The overall aim of this study was to analyze the clinicopathological outcomes of familial micro-PTC.

METHODS

Between 1996 and 2006, 2071 patients underwent thyroid surgery for papillary thyroid carcinoma. The clinicopathological outcomes for familial PTC and sporadic PTC were compared, and familial micro-PTC data were sub-analyzed.

RESULTS

There were significant differences in multifocality, bilaterality, extent of surgery, and recurrence between familial PTC and sporadic PTC (p<0.05). There was no significant difference in the number of affected family members in the familial PTC group. In patients with familial micro-PTC, less aggressiveness was noted in multifocality, extrathyroidal invasion, tumor stage at time of initial surgery, central lymph node metastasis, and recurrence than in those with familial PTC tumors>1 cm in diameter (p<0.05). The multivariate analysis including recurrence showed no significant difference between familial micro-PTC patients and sporadic micro-PTC patients.

CONCLUSION

When familial PTC was compared with sporadic PTC, our results support the recommendation for more invasive familial PTC surgery. However, familial micro-PTC outcomes differed from familial PTC tumors>1.0 cm in diameter. It was similar to sporadic micro-PTC, illustrating that familial micro-PTC is less aggressive and that a less invasive surgical treatment could be considered.

A Comprehensive Meta-analysis of Case-Control Association Studies to Evaluate Polymorphisms Associated with the Risk of Differentiated Thyroid Carcinoma

BACKGROUND

Linkage analyses and association studies suggested that inherited genetic variations play a role in the development of differentiated thyroid carcinoma (DTC).

METHODS

We combined the results from a genome-wide association study (GWAS) performed by our group and from published studies on DTC. With a first approach, we evaluated whether a SNP published as associated with the risk of DTC could replicate in our GWAS (using FDR as adjustment for multiple comparisons). With the second approach, meta-analyses were performed between literature and GWAS when both sources suggested an association, increasing the statistical power of the analysis.

RESULTS

rs1799814 (CYP1A1), rs1121980 (FTO), and 3 SNPs within 9q22 (rs965513, rs7048394, and rs894673) replicated the associations described in the literature. In addition, the meta-analyses between literature and GWAS revealed 10 more SNPs within 9q22, six within FTO, two within SOD1, and single variations within HUS1, WDR3, UGT2B7, ALOX12, TICAM1, ATG16L1, HDAC4, PIK3CA, SULF1, IL11RA, VEGFA, and 1p31.3, 2q35, 8p12, and 14q13.

CONCLUSION

This analysis confirmed several published risk loci that could be involved in DTC predisposition.

IMPACT

These findings provide evidence for the role of germline variants in DTC etiology and are consistent with a polygenic model of the disease. Cancer Epidemiol Biomarkers Prev; 25(4); 700-13. ©2016 AACR.

Extending the Impact of RAC1b Overexpression to Follicular Thyroid Carcinomas

RAC1b is a hyperactive variant of the small GTPase RAC1 known to be a relevant molecular player in different cancers. Previous studies from our group lead to the evidence that its overexpression in papillary thyroid carcinoma (PTC) is associated with an unfavorable prognosis. In the present study, we intended to extend the analysis of RAC1b expression to thyroid follicular neoplasms and to seek for clinical correlations. RAC1b expression levels were determined by RT-qPCR in thyroid follicular tumor samples comprising 23 follicular thyroid carcinomas (FTCs) and 33 follicular thyroid adenomas (FTAs). RAC1b was found to be overexpressed in 33% of carcinomas while no RAC1b overexpression was documented among follicular adenomas. Patients with a diagnosis of FTC were divided into two groups based on longitudinal evolution and final outcome. RAC1b overexpression was significantly associated with both the presence of distant metastases (P = 0.01) and poorer clinical outcome (P = 0.01) suggesting that, similarly to that previously found in PTCs, RAC1b overexpression in FTCs is also associated with worse outcomes. Furthermore, the absence of RAC1b overexpression in follicular adenomas hints its potential as a molecular marker likely to contribute, in conjunction with other putative markers, to the preoperative differential diagnosis of thyroid follicular lesions.

The management of thyroid nodules and cancer in the molecular era

The incidence of thyroid cancer is increasing worldwide. Current standards in the diagnosis and management of thyroid cancer are limited by the uncertainty of fine-needle aspiration samples that are indeterminate in nature. Molecular markers have the potential to improve the accuracy of thyroid fine-needle aspiration and to aid the physician in giving a more accurate diagnosis and prognosis. This paper summarizes the various molecular markers currently available.

Analysis of RAS mutation and PAX8/PPARγ rearrangements in follicular-derived thyroid neoplasms in a Korean population: frequency and ultrasound findings

OBJECTIVE

To investigate the frequency and ultrasonography (US) findings of RAS mutations and PAX8/PPARγ rearrangements between follicular thyroid adenomas (FTAs) and follicular thyroid carcinomas (FTCs) in a Korean population.

METHODS

RAS mutations and PAX8/PPARγ rearrangements in 56 FTAs and 35 FTCs were analyzed. We also analyzed the US findings of FTCs and FTAs.

RESULTS

16 nodules of 35 FTCs (45.7 %) and 19 nodules of 56 FTAs (33.9 %) harbored RAS mutations. Three FTCs and three FTAs showed two point mutations simultaneously. K-RAS codon 12-13 (n = 6, 31.6 %), N-RAS codon 61 (n = 5, 26.3 %), H-RAS codon 61 (n = 4, 21.1 %), K-RAS codon 61 (n = 3, 15.8 %), and N-RAS codon 12-13 (n = 1, 5.3 %) were found in FTCs, and N-RAS codon 61 (n = 10, 45 %), K-RAS codon 12-13 (n = 5, 22.7 %), H-RAS codon 61 (n = 5, 22.7 %), K-RAS codon 61 (n = 1, 4.5 %), and N-RAS codon 12-13 (n = 1, 4.5 %) were observed in FTAs. 4 of 56 (7.1 %) FTAs and 1 of 35 (2.9 %) FTCs represented PAX8/PPARγ rearrangements, respectively (P = 0.645). The absence of a hypoechoic rim (P = 0.021) and presence of calcifications (P = 0.049) were significantly associated with FTCs compared with FTAs.

CONCLUSIONS

RAS mutation frequency targeting the Korean population showed a 45.7 % in FTCs and 35.7 % in FTAs, and PAX8/PPARγ rearrangements were more frequently showed in FTAs. K-RAS codon 12-13 was the most common RAS mutation in FTCs, whereas N-RAS codon 61 was more frequent in FTAs. The presence of calcifications and absence of a hypoechoic rim showed more frequently in FTCs.

Management Guidelines for Children with Thyroid Nodules and Differentiated Thyroid Cancer

BACKGROUND

Previous guidelines for the management of thyroid nodules and cancers were geared toward adults. Compared with thyroid neoplasms in adults, however, those in the pediatric population exhibit differences in pathophysiology, clinical presentation, and long-term outcomes. Furthermore, therapy that may be recommended for an adult may not be appropriate for a child who is at low risk for death but at higher risk for long-term harm from overly aggressive treatment. For these reasons, unique guidelines for children and adolescents with thyroid tumors are needed.

METHODS

A task force commissioned by the American Thyroid Association (ATA) developed a series of clinically relevant questions pertaining to the management of children with thyroid nodules and differentiated thyroid cancer (DTC). Using an extensive literature search, primarily focused on studies that included subjects ≤18 years of age, the task force identified and reviewed relevant articles through April 2014. Recommendations were made based upon scientific evidence and expert opinion and were graded using a modified schema from the United States Preventive Services Task Force.

RESULTS

These inaugural guidelines provide recommendations for the evaluation and management of thyroid nodules in children and adolescents, including the role and interpretation of ultrasound, fine-needle aspiration cytology, and the management of benign nodules. Recommendations for the evaluation, treatment, and follow-up of children and adolescents with DTC are outlined and include preoperative staging, surgical management, postoperative staging, the role of radioactive iodine therapy, and goals for thyrotropin suppression. Management algorithms are proposed and separate recommendations for papillary and follicular thyroid cancers are provided.

CONCLUSIONS

In response to our charge as an independent task force appointed by the ATA, we developed recommendations based on scientific evidence and expert opinion for the management of thyroid nodules and DTC in children and adolescents. In our opinion, these represent the current optimal care for children and adolescents with these conditions.

Identification and characterization of two novel germline RET variants associated with medullary thyroid carcinoma

Activating germline mutations in the RET proto-oncogene are responsible for about 98 % of the familial forms of medullary thyroid carcinoma (MTC), which represent 25 % of all MTC cases. The search for germline mutations in this gene is important for the recognition of hereditary forms of MTC and further identification of at-risk relatives who may benefit from early clinical intervention. Genotype-phenotype correlations are well established for most disease-causing RET mutations, allowing risk stratification. The association of a new RET variant with the MTC phenotype and familial predisposition requires the assessment of its functional and clinical significance. The aim of this study was to evaluate the oncogenic potential of two newly identified RET germline variants associated with late-onset MTC. In vitro functional assays were designed to address the transforming potential of novel RET variants, through their expression in non-transformed cells, and comparing their effect with wild-type RET. The new variants were identified in codons 515 (p.C515W) and 636 (p.T636M) located, respectively, in exons 8 and 11, thus resulting in amino acid substitutions in the extracellular region of the tyrosine kinase receptor RET. Through functional assays, we observed increased cell growth and proliferation, loss of contact inhibition, and a stimulation of cell migration, suggesting that these new RET variants hold some relevant transforming potential. The transforming potential of these novel RET variants was of low-grade, when compared to that of RET MEN2A-causing mutation p.C634R, probably explaining the mild phenotype characterized by late onset and low clinical aggressiveness.

Clusterin transcript variants expression in thyroid tumor: a potential marker of malignancy?

BACKGROUND

Clusterin (CLU) is a ubiquitous multifunctional factor involved in neoplastic transformation. The CLU transcript variants and protein forms play a crucial role in balancing cells proliferation and death.

METHODS

We investigated the regulation of CLU transcript variants expression in an in vivo model system consisting of both neoplastic tissues and fine needle aspiration biopsy (FNAB) samples isolated from patients undergoing thyroidectomy.

RESULTS

The immunohistochemical analyses showed an overall CLU up-regulation in papillary carcinoma. A specific CLU2 transcript variant increase was registered using qPCR in papillary carcinomas while CLU1 decreased. In addition, the analysis of CLU transcripts expression level showed an increase of the CLU2 transcript in the TIR 3 patients with histologically confirmed thyroid cancer.

CONCLUSIONS

Our results suggest the existence of a specific alteration of CLU2:CLU1 ratio towards CLU2, thus providing the first circumstantial evidence for the potential use of CLU transcript variants as effective biomarkers for a more accurate assessment of the so called "indeterminate" thyroid nodules.

VE1 immunohistochemical detection of the BRAF V600E mutation in thyroid carcinoma: a review of its usefulness and limitations

The BRAF V600E mutation is a valuable prognostic factor in thyroid carcinoma despite lingering debate. Successful immunohistochemical (IHC) detection of the BRAF V600E mutation using a VE1 antibody was introduced recently. The objective of this study was to verify the usefulness of IHC detection of the BRAF V600E mutation in thyroid carcinoma using the VE1 antibody. IHC detection of BRAF V600E was performed on various thyroid carcinoma subtypes. IHC results were compared with those obtained from real-time polymerase chain reaction (PCR) detection. Discordant cases were re-examined using a direct sequencing method following nested PCR amplification. The BRAF V600E mutation was detected in 68 % (71/104) of papillary carcinoma cases and 78 % (7/9) of anaplastic carcinoma cases. The mutation was not detected in patients with follicular carcinoma (0/18) or in medullary carcinoma (0/21). The overall sensitivity and specificity of IHC using the VE1 antibody were 100 and 94 %, respectively, suggesting that molecular-based results were indeterminable in four VE1-positive cases. IHC using the VE1 antibody is a highly sensitive and specific method for BRAF V600E mutation detection and may represent a future replacement for DNA-based molecular tests.

Genome-wide expression analysis suggests a crucial role of dysregulation of matrix metalloproteinases pathway in undifferentiated thyroid carcinoma

Background

Thyroid cancer (TC) is the most common malignant cancer of the Endocrine System. Histologically, there are three main subtypes of TC: follicular, papillary and anaplastic. Diagnosing a thyroid tumor subtype with a high level of accuracy and confidence is still a difficult task because genetic, molecular and cellular mechanisms underlying the transition from differentiated to undifferentiated thyroid tumors are not well understood.

A genome-wide analysis of these three subtypes of thyroid carcinoma was carried out in order to identify significant differences in expression levels as well as enriched pathways for non-shared molecular and cellular features between subtypes.

Results

Inhibition of matrix metalloproteinases pathway is a major event involved in thyroid cancer progression and its dysregulation may result crucial for invasiveness, migration and metastasis. This pathway is drastically altered in ATC while in FTC and PTC, the most important pathways are related to DNA-repair activation or cell to cell signaling events.

Conclusion

A progression from FTC to PTC and then to ATC was detected and validated on two independent datasets. Moreover, PTX3, COLEC12 and PDGFRA genes were found as possible candidates for biomarkers of ATC while GPR110 could be tested to distinguish PTC over other tumor subtypes. The genome-wide analysis emphasizes the preponderance of pathway-dysregulation mechanisms over simple gene-malfunction as the main mechanism involved in the development of a cancer phenotype.

Electronic supplementary material

The online version of this article (doi:10.1186/s12864-015-1372-0) contains supplementary material, which is available to authorized users.

Association Analysis of MET Gene Polymorphism with Papillary Thyroid Carcinoma in a Chinese Population

To investigate the association of MET SNPs with gender disparity in thyroid tumors, as well as the metastasis and prognosis of patients, 858 patients with papillary thyroid carcinoma (PTC), 556 patients with nodular goiter, and 896 population-based normal controls were recruited. The genotyping of MET SNPs was carried out using the Sequenom MassARRAY system. The distribution of MET SNPs (rs1621 and rs6566) was different among groups. Gender stratification analysis revealed a significant association between the rs1621 genotype and PTC in female patients (P = 0.037), but not in male patients (P > 0.05). For female patients, the rs1621 AG genotype was significantly higher in patients with PTC than in normal controls (P = 0.01) and revealed an increasing risk of PTC (OR: 1.465, 95% CI: 1.118-1.92). However, association analysis of the rs1621 genotype with metastasis and prognosis revealed no significant correlation in both male and female patients. The findings of our study showed that polymorphism of SNP locus rs1621 in MET gene may be associated with gender disparity in PTC. Higher AG genotypes in rs1621 were correlated with PTC in female patients, but not in male patients.