Molecular pathogenesis of follicular cell derived thyroid cancers

Obesity and thyroid cancer: unraveling the connection through a systematic review and meta-analysis of cohort studies

Background

The relationship between adiposity indicators and thyroid cancer (TC) risk has garnered increasing attention due to the rising prevalence of obesity and its potential impact on cancer incidence. We conducted a comprehensive meta-analysis to investigate this association across various effect measures.

Method

Until July 2022, a comprehensive search of databases was conducted to identify cohort studies that assessed the association between adiposity and the development of TC. Meta-analysis was performed using random effects models. Subgroup analyses were conducted to explore heterogeneity. Publication bias was assessed using Begg's tests.

Results

A systematic literature search identified 27 eligible studies reporting odds ratios (OR), relative risks (RR), or hazard ratios (HR) as effect measures. Pooling the studies irrespective of the effect measure, a significant positive association between adiposity indicators and TC risk was observed, yielding an effect estimate of 1.16 (95% CI 1.12-1.21). The combined effect estimate for OR/RR studies was 1.10 (95%CI 1.04-1.17), while HR studies yielded an effect estimate of 1.20 (95%CI 1.13-1.26). Subgroup analyses revealed associations across different age groups, obesity indices, and regions, with some variations based on effect measure. Meta-regression identified follow-up duration as a confounding factor only in HR studies.

Conclusion

The synthesis of 27 studies with diverse designs and populations underscores a robust positive association between adiposity and TC risk, providing compelling evidence for the potential role of increased adiposity in TC development.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40200-024-01425-3.

Survival Trends in Pediatric Differentiated Thyroid Cancer: A Middle Eastern Perspective

Pediatric Differentiated Thyroid Cancer (pedDTC) is a rare pediatric malignancy with an increasing incidence over time. To date, there is a paucity of literature specifically addressing pedDTC within the context of Middle Eastern ethnicity. This retrospective study aimed to assess the risk-stratifying factors for overall survival (OS) and event-free survival (EFS) in pediatric DTC patients from Iraq and Jordan. The medical records of 81 patients from two tertiary cancer institutes were retrieved. Kaplan-Meier analysis was employed to investigate OS and EFS, and the Cox proportional hazards model was employed to estimate hazard ratios. All patients underwent surgery and radioactive iodine therapy, with a median age of 14 and an interquartile range of 12-15. Lymph node involvement was observed in 55% of cases, while distant metastases were present in 13.5%. After a median follow-up period of 68 months, the 10-year survival rate was determined to be 94%, while the 10-year EFS rate was 58%. EFS was negatively impacted by cervical lymph node metastases and early age of diagnosis (p ≤ 0.01, each). Therefore, pediatrics with initial cervical lymph node metastases and those diagnosed before puberty tend to experience poorer EFS, which may justify the need for more aggressive management plans.

Role of Truncated O-GalNAc Glycans in Cancer Progression and Metastasis in Endocrine Cancers

Glycans are an essential part of cells, playing a fundamental role in many pathophysiological processes such as cell differentiation, adhesion, motility, signal transduction, host-pathogen interactions, tumour cell invasion, and metastasis development. These glycans are also able to exert control over the changes in tumour immunogenicity, interfering with tumour-editing events and leading to immune-resistant cancer cells. The incomplete synthesis of O-glycans or the formation of truncated glycans such as the Tn-antigen (Thomsen nouveau; GalNAcα- Ser/Thr), its sialylated version the STn-antigen (sialyl-Tn; Neu5Acα2-6GalNAcα-Ser/Thr) and the elongated T-antigen (Thomsen-Friedenreich; Galβ1-3GalNAcα-Ser/Thr) has been shown to be associated with tumour progression and metastatic state in many human cancers. Prognosis in various human cancers is significantly poor when they dedifferentiate or metastasise. Recent studies in glycobiology have shown truncated O-glycans to be a hallmark of cancer cells, and when expressed, increase the oncogenicity by promoting dedifferentiation, risk of metastasis by impaired adhesion (mediated by selectins and integrins), and resistance to immunological killing by NK cells. Insight into these truncated glycans provides a complimentary and attractive route for cancer antigen discovery. The recent emergence of immunotherapies against cancers is predicted to harness the potential of using such agents against cancer-associated truncated glycans. In this review, we explore the role of truncated O-glycans in cancer progression and metastasis along with some recent studies on the role of O-glycans in endocrine cancers affecting the thyroid and adrenal gland.

PAX8 in the Junction between Development and Tumorigenesis

Normal processes of embryonic development and abnormal transformation to cancer have many parallels, and in fact many aberrant cancer cell capabilities are embryonic traits restored in a distorted, unorganized way. Some of these capabilities are cell autonomous, such as proliferation and resisting apoptosis, while others involve a complex interplay with other cells that drives significant changes in neighboring cells. The correlation between embryonic development and cancer is driven by shared proteins. Some embryonic proteins disappear after embryogenesis in adult differentiated cells and are restored in cancer, while others are retained in adult cells, acquiring new functions upon transformation to cancer. Many embryonic factors embraced by cancer cells are transcription factors; some are master regulators that play a major role in determining cell fate. The paired box (PAX) domain family of developmental transcription factors includes nine members involved in differentiation of various organs. All paired box domain proteins are involved in different cancer types carrying pro-tumorigenic or anti-tumorigenic roles. This review focuses on PAX8, a master regulator of transcription in embryonic development of the thyroid, kidney, and male and female genital tracts. We detail the role of PAX8 in each of these organ systems, describe its role during development and in the adult if known, and highlight its pro-tumorigenic role in cancers that emerge from PAX8 expressing organs.

Adherence to the Mediterranean Diet as a Modifiable Risk Factor for Thyroid Nodular Disease and Thyroid Cancer: Results From a Pilot Study

Iodine deficiency is the most important established nutritional risk factor for the development of thyroid nodular disease. Nevertheless, to the best of our knowledge, to date no study focused on the association between the adherence to the Mediterranean diet (MD) and thyroid nodular disease. Adherence to the MD was evaluated using the PREvención con DIetaMEDiterránea (PREDIMED) questionnaire. Physical activity, smoking habits, and anthropometric parameters were studied. PREDIMED was used to evaluate the degree of adherence to the MD. Evaluation of fine needle aspiration cytology of thyroid lesions based on 2013 Italian thyroid cytology classification system. Cytology of thyroid nodules was carried out through sonography-guided fine-needle aspiration and patients were divided into 5 categories: TIR2, TIR3a, TIR3b, TIR4, and TIR5. The study population consisted of 794 subjects (554 females, 69.8%), aged 18–65 years, with BMIs ranging from 19.4 to 55.3 kg/m². Thyroid nodular disease was present in 391 participants (49.2%), and the most frequent cytological categories was TIR2 (18.3 %), followed by a TIR4 (8.9 %). The presence of thyroid nodules was also significantly associated with the lowest adherence to the MD (OR 6.16, p < 0.001). Patients with TIR5 had the lower adherence to the MD (2.15 ± 1.12 score) compared to other TIRs (p < 0.001). The cytological category with high-risk of malignancy (TIR4/TIR5) was significantly associated with the lowest adherence to the MD (OR 137.55, p < 0.001) and PREDIMED score (OR = 0.33, p < 0.001, 95% IC = 0.26–0.41, R² = 0.462). At multiple regression analysis, PREDIMED score was the main predictor of both the presence of nodules (p < 0.001) and the cytological category with high-risk of malignancy (p < 0.001). At ROC analysis PREDIMED score ≤ 5 and ≤ 4 (p = 0.001) were the values that predicted the presence of thyroid nodular disease and cytological category with high-risk of malignancy, respectively. In conclusion, our study demonstrated that the low adherence to the MD is associated with the presence of thyroid nodular disease and in particular with those at high-risk of malignancy.

Impaired Glucose Metabolism, Anti-Diabetes Medications, and Risk of Thyroid Cancer

Simple Summary

An epidemiologic link exists between obesity, insulin resistance, diabetes, and some cancers, such as breast cancer and colon cancer. The prevalence of obesity and diabetes is increasing, and additional epidemiologic data suggest that there may be a link between obesity and risk of thyroid abnormalities. Factors that may link obesity and diabetes with thyroid proliferative disorders include elevated circulating levels of insulin, increased body fat, high blood sugars, and exogenous insulin use. However, mechanisms underlying associations of obesity, diabetes, and thyroid proliferative disorders are not yet fully understood. The present manuscript reviews and summarizes current evidence of mechanisms and epidemiologic associations of obesity, insulin resistance, and use of anti-diabetes medications with benign and malignant proliferative disorders of the thyroid.

Abstract

The prevalence of obesity is progressively increasing along with the potential high risk for insulin resistance and development of type 2 diabetes mellitus. Obesity is associated with increased risk of many malignancies, and hyperinsulinemia has been proposed to be a link between obesity and cancer development. The incidence of thyroid cancer is also increasing, making this cancer the most common endocrine malignancy. There is some evidence of associations between obesity, insulin resistance and/or diabetes with thyroid proliferative disorders, including thyroid cancer. However, the etiology of such an association has not been fully elucidated. The goal of the present work is to review the current knowledge on crosstalk between thyroid and glucose metabolic pathways and the effects of obesity, insulin resistance, diabetes, and anti-hyperglycemic medications on the risk of thyroid cancer development.

Ambient particulate matter air pollution is associated with increased risk of papillary thyroid cancer

BACKGROUND

The association between exposure to air pollution and papillary thyroid carcinoma is unknown. We sought to estimate the relationship between long-term exposure to the fine (diameter ≤ 2.5 μm) particulate matter component of air pollution and the risk of papillary thyroid cancer.

METHODS

Adult (age ≥18) patients with newly diagnosed papillary thyroid carcinoma between January 1, 2013 and December 31, 2016 across a single health system were identified using electronic medical records. Data from 1,990 patients with papillary thyroid carcinoma were compared with 3,980 age- and sex-matched control subjects without any evidence of thyroid disease. Cumulative fine (diameter <2.5 μm) particulate matter exposure was estimated by incorporating patients' residential zip codes into a deep learning neural networks model, which uses both meteorological and satellite-based measurements. Conditional logistic regression was performed to assess for association between papillary thyroid carcinoma and increasing fine (diameter ≤2.5 μm) particulate matter concentrations over 1, 2, and 3 years of cumulative exposure preceding papillary thyroid carcinoma diagnosis.

RESULTS

Increased odds of developing papillary thyroid carcinoma was associated with a 5 μg/m³ increase of fine (diameter ≤2.5 μm) particulate matter concentrations over 2 years (adjusted odds ratio = 1.18, 95% confidence interval: 1.00-1.40) and 3 years (adjusted odds ratio = 1.23, 95% confidence interval: 1.05-1.44) of exposure. This risk differed by smoking status (p_interaction = 0.04). Among current smokers (n = 623), the risk of developing papillary thyroid carcinoma was highest (adjusted odds ratio = 1.35, 95% confidence interval: 1.12-1.63).

CONCLUSION

Increasing concentration of fine (diameter ≤2.5 μm) particulate matter in air pollution is significantly associated with the incidence of papillary thyroid carcinoma with 2 and 3 years of exposure. Our novel findings provide additional insight into the potential associations between risk factors and papillary thyroid carcinoma and warrant further investigation, specifically in areas with high levels of air pollution both nationally and internationally.

Ionising Radiation Promotes Invasive Potential of Breast Cancer Cells: The Role of Exosomes in the Process

Along with the cells that are exposed to radiation, non-irradiated cells can unveil radiation effects as a result of intercellular communication, which are collectively defined as radiation induced bystander effects (RIBE). Exosome-mediated signalling is one of the core mechanisms responsible for multidirectional communication of tumor cells and their associated microenvironment, which may result in enhancement of malignant tumor phenotypes. Recent studies show that exosomes and exosome-mediated signalling also play a dynamic role in RIBE in cancer cell lines, many of which focused on altered exosome cargo or their effects on DNA damage. However, there is a lack of knowledge regarding how these changes in exosome cargo are reflected in other functional characteristics of cancer cells from the aspects of invasiveness and metastasis. Therefore, in the current study, we aimed to investigate exosome-mediated bystander effects of 2 Gy X-ray therapeutic dose of ionizing radiation on the invasive potential of MCF-7 breast cancer cells in vitro via assessing Matrigel invasion potential, epithelial mesenchymal transition (EMT) characteristics and the extent of glycosylation, as well as underlying plausible molecular mechanisms. The findings show that exosomes derived from irradiated MCF-7 cells enhance invasiveness of bystander MCF-7 cells, possibly through altered miRNA and protein content carried in exosomes.

In vitro antitumoral effects of the steroid ouabain on human thyroid papillary carcinoma cell lines

Ouabain is a steroid described as a compound extracted from plants that is capable of binding to Na⁺ , K⁺ -ATPase, inhibiting ion transport and triggering cell signaling pathways. Due to its positive ionotropic effect, ouabain was used for more than 200 years for the treatment of cardiac dysfunctions. Numerous antitumor effects of ouabain have been described so far; however, its role on thyroid cancer is still poorly understood. Therefore, the aim of the present work was to evaluate the effect of ouabain on the biology of human papillary thyroid cancer cells. For this, three human thyroid cell lines were used: NTHY-ori, a non-tumor lineage, BCPAP and TPC-1, both derived from papillary carcinomas. Cells were cultured in the presence or absence of ouabain. Subsequently, we evaluated its effects on the viability, cell death, cell cycle, and migratory ability of these cell lines. We also investigated the impact of ouabain in IL-6/IL-6R and epithelial to mesenchymal transition markers expression. Our results indicate that ouabain (10^-7 M), decreased the number of NTHY-ori, TPC-1 and BCPAP viable cells and induced cell cycle arrest after in vitro culture, but did not appear to promote cell death. In TPC-1 cells ouabain also inhibited cell migration; increased IL-6/IL-6R expression and IL-6 secretion; and diminished vimentin and SNAIL-1 expression. Collectively, our results indicate that ouabain has an antitumoral role on human papillary thyroid carcinomas in vitro. Even though additional studies are necessary, our work contributes to the discussion of the possibility of new clinical trials of ouabain.

Somatic Genomic Changes in the Formation of Differentiated Thyroid Carcinoma

Globally, the diffuse goiter affects more than 10% of the population and in some regions is endemic. Thyroid nodules are found in approximately 5% of the population using the oldest method for thyroid examination – palpation. When performing ultrasound screening, this percentage increases significantly and reaches between 20 and 75% of the total population. Thyroid carcinoma is a rare malignancy and accounts for up to 1% of all malignant tumors. It is the most common endocrine cancer and is clinically manifested as a thyroid nodule. Somatic mutations play an important role in its development. Differentiation of benign and malignant thyroid nodules is of great importance due to the different therapeutic approach. Therefore, new diagnostic tools are sought to help distinguish the two. Despite the progress in our knowledge of carcinogenesis in recent years, a number of key issues still remain unanswered. The establishment of new rare somatic mutations can improve pre-surgical diagnosis and optimize post-operative strategies for the treatment of thyroid carcinoma. Next-generation sequencing (NGS) allows for extensive mutation and genome rearrangements tracking. The results obtained with NGS provide the basis for the development of new approach for systematic genetic screening, at prevention, early diagnosis, accurate prognosis, and targeted therapy of this disorder.

Metabolic Syndrome and the Risk of Thyroid Cancer: A Nationwide Population-Based Cohort Study

Background: The association of metabolic syndrome and its components with the risk of thyroid cancer is unclear. Thus, we conducted a large-scale, nationwide, population-based, cohort study to investigate this relationship. Methods: We studied 9,890,917 adults without thyroid cancer from the Korean National Health Insurance health checkup database from January 1 to December 31, 2009. Individuals with at least three of the following five components were diagnosed with metabolic syndrome: abdominal obesity, hypertriglyceridemia, low high-density lipoprotein-cholesterol levels, elevated blood pressure, and hyperglycemia. Multivariate Cox proportional hazards models were used to estimate thyroid cancer risk. Results: During the average 7.2 years of follow-up, 77,133 thyroid cancer cases were newly identified. The thyroid cancer risk was higher in the metabolic syndrome group than in the nonmetabolic syndrome group (hazard ratio [HR] 1.15 [95% confidence interval, CI 1.13-1.17]). The association between metabolic syndrome and thyroid cancer risk was significant in the obese group (HR 1.10 [CI 1.07-1.13]) and not in the nonobese group (HR 1.002 [CI 0.98-1.03]). The effect of metabolic syndrome on the risk of thyroid cancer differs according to obesity (p for interaction = 0.017). People with all five components of metabolic syndrome had a 39% higher risk than those without any components (HR 1.39 [CI 1.33-1.44]). The higher risk of thyroid cancer in people with all five components was significant in the obese group (HR 1.29 [CI 1.21-1.38]), but not in the nonobese group (HR 1.06 [CI 0.98-1.14]). There was a significant interaction between the number of metabolic syndrome components and obesity (p for interaction <0.0001). For the combined effect of obesity and metabolic syndrome on the risk of thyroid cancer, obese men with metabolic syndrome had the highest risk of thyroid cancer compared with those without (HR 1.58 [CI 1.52-1.64]), but obese women with metabolic syndrome did not. Conclusions: Metabolic syndrome was associated with an increased risk of thyroid cancer in the Korean general population. Metabolic syndrome had a more significant risk of thyroid cancer in the obese group. Metabolic syndrome and obesity were associated with a higher risk of thyroid cancer in men but not in women.

Current and Future Role of Tyrosine Kinases Inhibition in Thyroid Cancer: From Biology to Therapy

Thyroid cancer represents a heterogenous disease whose incidence has increased in the last decades. Although three main different subtypes have been described, molecular characterization is progressively being included in the diagnostic and therapeutic algorithm of these patients. In fact, thyroid cancer is a landmark in the oncological approach to solid tumors as it harbors key genetic alterations driving tumor progression that have been demonstrated to be potential actionable targets. Within this promising and rapid changing scenario, current efforts are directed to improve tumor characterization for an accurate guidance in the therapeutic management. In this sense, it is strongly recommended to perform tissue genotyping to patients that are going to be considered for systemic therapy in order to select the adequate treatment, according to recent clinical trials data. Overall, the aim of this article is to provide a comprehensive review on the molecular biology of thyroid cancer focusing on the key role of tyrosine kinases. Additionally, from a clinical point of view, we provide a thorough perspective, current and future, in the treatment landscape of this tumor.

Gene Expression Patterns Unveil New Insights in Papillary Thyroid Cancer

Background and objectives: Papillary thyroid carcinoma is the most frequent variety of all malignant endocrine tumors. It represents a heterogeneous malignancy with various clinical outcomes, emphasizing the need to identify powerful biomarkers with clinical relevance. Materials and Methods: Available gene expression data (level 3) for thyroid cancers were downloaded from the Cancer Genome Atlas (TCGA), followed by bioinformatic analyses performed on the data set. Results: Based on gene expression analysis, we were able to identify common and specific gene signatures for the three main types of papillary thyroid carcinoma (classical, follicular variant, and tall-cell). The survival rate was not significantly different among the main subtypes, but we were able to identify a biological adhesion signature with impact in patient prognostic. Conclusions: Taken together, the gene expression signature and particular adhesion signature, along with ITGA10 and MSLN in particular, could be used as a prognostic tool with important clinical relevance.

Role of P53, E-cadherin and BRAF as predictors of regional nodal recurrence for papillary thyroid cancer

BACKGROUND

Regional nodal recurrence (RNR) in patients diagnosed with papillary thyroid carcinoma (PTC) has increased. Variable immunohistochemical (IHC) markers have been studied for predicting the likelihood of PTC for recurrence. We aimed to clarify the IHC expression of p53, Ecadherin and BRAF as potential markers of RNR in PTC.

METHOD

145 (73 study group and 72 control group) patients with PTC were analyzed retrospectively between January 2010 and June 2017. Further classification to a specific histological variant was done, and IHC expression of p53, Ecadherin and BRAF was analyzed both in the primary tumor and in nodal recurrence.

RESULTS

Regarding the risk of RNR, we found certain clinicopathologic features as elder age ≥55 years, tumor size >1 cm, presence of microscopic extrathyroid extension, presence of lymphovascular emboli, and conventional papillary subtype. Furthermore, IHC results for negative E-cadherin, and positive P53 and BRAF are significant risk factors, while radioactive iodine (RAI) adjuvant therapy decrease recurrence risk.

CONCLUSION

We found several risk factors for RNR in PTC diagnosed patients, all of which are easily achievable in clinical settings. In this regard, we suggested that patients with specific clinicopathologic and immunohistochemical features have strict follow up for early detection of RNR as it has a great impact on their survival.

Mathematical models applied to thyroid cancer

Thyroid cancer is the most prevalent endocrine neoplasia in the world. The use of mathematical models on the development of tumors has yielded numerous results in this field and modeling with differential equations is present in many papers on cancer. In order to know the use of mathematical models with differential equations or similar in the study of thyroid cancer, studies since 2006 to date was reviewed. Systems with ordinary or partial differential equations were the means most frequently adopted by the authors. The models deal with tumor growth, effective half-life of radioiodine applied after thyroidectomy, the treatment with iodine-131, thyroid volume before thyroidectomy, and others. The variables usually employed in the models includes tumor volume, thyroid volume, amount of iodine, thyroglobulin and thyroxine hormone, radioiodine activity, and physical characteristics such as pressure, density, and displacement of the thyroid molecules. In conclusion, the mathematical models used so far with differential equations approach several aspects of thyroid cancer, including participation in methods of execution or follow-up of treatments. With the development of new models, an increase in the current understanding of the detection, evolution, and treatment of diseases is a step that should be considered.

Effect of insulin on thyroid cell proliferation, tumor cell migration, and potentially related mechanisms

BACKGROUND

Diabetes has recently been identified as a risk factor for a variety of cancers, possibly due to hyperinsulinemia or exogenous insulin use. Thyroid cancer is the most common endocrine malignancy, and its incidence has been exponentially increasing worldwide at an alarming rate. The aim of this study was to establish whether insulin use affects thyroid cancer development and progression, specifically cell proliferation and migration in vitro.

METHODS

In this study, we investigated the effects of the insulin agents most commonly used in the clinic, regular human insulin (HI) and insulin glargine (IG), on the proliferation and migration of thyroid cells.

RESULTS

Both HI and IG affected the thyroid cells in a dose-dependent manner and at high concentrations significantly promoted thyroid cell proliferation and tumor cell migration. The promoting effect might be elicited by activation of the insulin receptor and insulin-like growth factor-1 receptor and through the downstream Akt-signaling pathway, which inhibits the activity of the tumor-suppressor FoxO3a. In particular, MAPK-signaling cascades were activated in papillary thyroid carcinoma cell-1 cells but not in follicular rat thyroid-5 cells.

CONCLUSION

The in vitro evidence demonstrated that HI and IG can promote thyroid cell proliferation and tumor cell migration at supraphysiological concentrations, but the effect was not significant at low concentrations. Whether high-dose insulins could affect diabetic patients with thyroid cancer or undetected (pre)cancerous lesions needs further in vivo study.

ABBREVIATIONS

HI: human regular insulin; IG: insulin glargine; IR: insulin receptor; IGF-1R: insulin-like growth factor-1 receptor; Akt: protein kinase B (PKB); MAPK: mitogen-activated protein kinase; FoxO3a: the forkhead box-containing protein: class O 3a.

Expression of Vascular Endothelial Growth Factor and Its Receptors in Thyroid Nodular Hyperplasia and Papillary Thyroid Carcinoma: A Tertiary Health Care Centre Based Study

Introduction:

Vascular endothelial growth factor (VEGF) is an angiogenic factor that plays an important role in thyroid cancer. VEGF is known to have high affinity to VEGF receptors such as VEGFR-1 (Flt-1) and VEGFR-2 (KDR). Papillary thyroid carcinoma (PTC) is the most common thyroid cancer and studies showed the increasing incidence of PTC arising in nodular hyperplasia. Targeted therapy on these growth factors and receptors are used in management of both differentiated and undifferentiated thyroid carcinoma. This study aims to determine the expression of VEGF and VEGF receptors (VEGFR) in thyroid nodular hyperplasia and PTC.

Methods:

A cross-sectional study based on paraffinized archival tissue blocks of 113 nodular hyperplasias and 67 PTC from the thyroidectomy specimens in the year of 2003 to 2014. The tissue sections were then stained by immunohistochemistry for VEGF, VEGFR-1 and VEGFR-2. The lymph node involvement and extrathyroid extension also were determined.

Results:

The mean age of PTC patients was 44.7±15.8 years and nodular hyperplasia were 42.2±13.6 years. There was a statistical difference of VEGFR-1 (p=0.028) and VEGFR-2 (p=0.003) expression between nodular hyperplasia and PTC. However, no significant difference of VEGF expression (p=0.576) between both diseases. Co-expression of VEGF and VEGFR-1 was significant in both nodular hyperplasia (p=0.016) and PTC (p=0.03), meanwhile no relevant relationship for VEGF and VEGFR-2 expression (p>0.05). No significant association (p>0.05) between lymph node status and extrathyroid extension with age groups, gender, VEGF and VEGFR expression.

Conclusions:

VEGF, VEGFR-1 and VEGFR-2 showed overexpression in both nodular hyperplasia and PTC. The expression of VEGFR-1 and VEGFR-2 are more significant in PTC with relevant co-expression of VEGF and VEGFR-1. Therefore, the inhibition of VEGFR offers a promising prospect for tumour management in thyroid carcinoma.

Association of obesity and diabetes with thyroid nodules

AIM

There are conflicting data concerning the possibility that obesity and diabetes raise the risk of thyroid nodules. The incidence of thyroid nodules is increasing, as is that of obesity and diabetes; therefore, understanding whether these metabolic and nutritional disorders influence nodular thyroid disease is important for organizing prevention strategies. This study investigated the association between thyroid nodules, obesity, diabetes, and dietary habits.

MATERIALS AND METHODS

A cohort of randomly selected adults (455 males, 746 females; age: 18-90 years) living in Palermo (Italy), a mild iodine deficiency area, was cross-sectionally investigated. Participants underwent high-resolution ultrasonographic evaluation of the thyroid, and answered a food frequency questionnaire. Laboratory blood measurements were obtained in 587 participants.

RESULTS AND DISCUSSION

Thyroid nodules were detected in 475 (39.5%) participants. The number of thyroid nodules was correlated with age (r = 0.19; P < 0.001), gender (r = 0.08; P = 0.005), and body mass index (r = 0.07; P = 0.02). No significant correlation was observed between the number of nodules and glycated hemoglobin, serum insulin concentrations, and homeostasis model assessment of insulin resistance. Age-adjusted and gender-adjusted prevalence of both overweight/obesity and type 2 diabetes of each group of participants divided according to the number of nodules significantly increased with the number of nodules (P < 0.05 in both cases). The group of participants with nodules exhibited a significantly lower age-adjusted and gender-adjusted habitual intake of milk (P = 0.02). Multivariate regression analysis showed that age, gender, body mass index, diabetes, and habitual consumption of milk were independently correlated with presence of thyroid nodules.

CONCLUSION

This study seems to indicate that an association exists between obesity, diabetes, and thyroid nodules.

Metabolic Reprogramming in Thyroid Carcinoma

Among all the adaptations of cancer cells, their ability to change metabolism from the oxidative to the glycolytic phenotype is a hallmark called the Warburg effect. Studies on tumor metabolism show that improved glycolysis and glutaminolysis are necessary to maintain rapid cell proliferation, tumor progression, and resistance to cell death. Thyroid neoplasms are common endocrine tumors that are more prevalent in women and elderly individuals. The incidence of thyroid cancer has increased in the Past decades, and recent findings describing the metabolic profiles of thyroid tumors have emerged. Currently, several drugs are in development or clinical trials that target the altered metabolic pathways of tumors are undergoing. We present a review of the metabolic reprogramming in cancerous thyroid tissues with a focus on the factors that promote enhanced glycolysis and the possible identification of promising metabolic targets in thyroid cancer.

Gene Expression (mRNA) Markers for Differentiating between Malignant and Benign Follicular Thyroid Tumours

Distinguishing between follicular thyroid cancer (FTC) and follicular thyroid adenoma (FTA) constitutes a long-standing diagnostic problem resulting in equivocal histopathological diagnoses. There is therefore a need for additional molecular markers. To identify molecular differences between FTC and FTA, we analyzed the gene expression microarray data of 52 follicular neoplasms. We also performed a meta-analysis involving 14 studies employing high throughput methods (365 follicular neoplasms analyzed). Based on these two analyses, we selected 18 genes differentially expressed between FTA and FTC. We validated them by quantitative real-time polymerase chain reaction (qRT-PCR) in an independent set of 71 follicular neoplasms from formaldehyde-fixed paraffin embedded (FFPE) tissue material. We confirmed differential expression for 7 genes (CPQ, PLVAP, TFF3, ACVRL1, ZFYVE21, FAM189A2, and CLEC3B). Finally, we created a classifier that distinguished between FTC and FTA with an accuracy of 78%, sensitivity of 76%, and specificity of 80%, based on the expression of 4 genes (CPQ, PLVAP, TFF3, ACVRL1). In our study, we have demonstrated that meta-analysis is a valuable method for selecting possible molecular markers. Based on our results, we conclude that there might exist a plausible limit of gene classifier accuracy of approximately 80%, when follicular tumors are discriminated based on formalin-fixed postoperative material.

A Concise Atlas of Thyroid Cancer Next-Generation Sequencing Panel ThyroSeq v.2

The next-generation sequencing technology allows high out-put genomic analysis. An innovative assay in thyroid cancer, ThyroSeq® was developed for targeted mutation detection by next generation sequencing technology in fine needle aspiration and tissue samples. ThyroSeq v.2 next generation sequencing panel offers simultaneous sequencing and detection in >1000 hotspots of 14 thyroid cancer-related genes and for 42 types of gene fusions known to occur in thyroid cancer. ThyroSeq is being increasingly used to further narrow the indeterminate category defined by cytology for thyroid nodules. From a surgical perspective, genomic profiling also provides prognostic and predictive information and closely relates to determination of surgical strategy. Both the genomic analysis technology and the informatics for the cancer genome data base are rapidly developing. In this paper, we have gathered existing information on the thyroid cancer-related genes involved in the initiation and progression of thyroid cancer. Our goal is to assemble a glossary for the current ThyroSeq genomic panel that can help elucidate the role genomics play in thyroid cancer oncogenesis.

N-acetylgalactosamine glycans function in cancer cell adhesion to endothelial cells: A role for truncated O-glycans in metastatic mechanisms

Failure in O-glycan chain extension exposing Tn antigen (GalNAc-O-Ser/Thr) is clinically associated with cancer metastasis. This study provides evidence of a functional role for aberrant GalNAc-glycans in cancer cell capture from blood flow and/or adhesion to endothelium. Adhesion of breast cancer cells to human umbilical vein endothelial cell monolayers was modelled under sweeping flow. Adhesion of metastatic, GalNAc glycan-rich, MCF7 and ZR 75 1 cells to endothelium increased over timepoints up to 1.5 hour, after which it plateaued. Adhesion was significantly inhibited (p < 0.001) when cell surface GalNAc-glycans were masked, an effect not seen in GalNAc glycan-poor, non-metastatic BT 474 cells. Masking irrelevant galactose- and mannose-glycans had no inhibitory effect. Imaging of cells post-adhesion over a 24 hour time course using confocal and scanning electron microscopy revealed that up to 6 hours post-adhesion, motile, rounded cancer cells featuring lamellipodia-like processes crawled on an intact endothelial monolayer. From 6-12 hours post-adhesion, cancer cells became stationary, adopted a smooth, circular flattened morphology, and endothelial cells retracted from around them leaving cleared zones in which the cancer cells proceeded to form colonies through cell division.

Unveiling a novel biomarker panel for diagnosis and classification of well-differentiated thyroid carcinomas

Thyroid cancer is the most common human endocrine malignancy with increasing global incidence. Papillary thyroid carcinomas (PTC) and follicular thyroid carcinomas (FTC) are well-differentiated thyroid cancers (WDTC) accounting for 95% of all thyroid cancer cases, with survival rates of almost 100% when diagnosed early. Since PTC and FTC have different modes of metastasis, they require different treatment strategies. Standard diagnosis by fine needle aspiration with cytopathological examination can be inaccurate in approximately 10-30% of all cases and difficult to definitively classify as WDTC. Currently, there is no single or panel of biomarkers available for thyroid cancer diagnosis and classification. This study identified novel biomarkers for thyroid cancer diagnosis and classification using proteomics, which may be translated into a biomarker panel for clinical application. Two-dimensional SDS-PAGE and mass spectrometry were used to identify potential biomarkers in papillary and follicular thyroid carcinoma cell lines, and the biomarkers were validated in five PTC and five FTC tissues, with their adjacent normal tissues from Thai patients. Eight biomarkers could distinguish PTC from normal tissues, namely enolase 1, triose phosphate isomerase, cathepsin D, annexin A2, cofilin 1, proliferating cell nuclear antigen (PCNA), copine 1 and heat shock protein 27 kDa (HSP27). These biomarkers can also discriminate FTC from normal tissues, except for annexin A2. On the contrary, annexin A2, cofilin 1, PCNA and HSP27 can be used to classify the types of WDTC. These findings have potential for use as a novel multi-marker panel for more accurate diagnosis and classification to better guide physicians on thyroid cancer treatment. Moreover, our results suggest the involvement of proteins in cell growth and proliferation, and the p53 pathway in the carcinogenesis of WDTC, which may lead to targeted therapy for thyroid cancer.

Associations of the BRAF (V600E) mutation and p53 protein expression with clinicopathological features of papillary thyroid carcinomas patients

The BRAF (V600E) mutation is the most prevalent type of genetic alteration that has been identified in papillary thyroid carcinoma (PTC); in addition, previous immunohistochemical studies have revealed the overexpression of p53 protein in PTC. The aim of the present study was to investigate the prevalence of the BRAF (V600E) mutation and the expression of p53 in PTC, as well as to determine any associations between these two factors and the clinicopathological features of PTC. The study was performed on 66 PTC patients who underwent surgical tumor resection between January and December 2012. Polymerase chain reaction-based DNA amplification was used to analyze extracted DNA from the tumor specimens in order to determine the prevalence of the BRAF (V600E) mutation. In addition, immunohistochemical analysis was employed in order to evaluate the protein expression of p53 in sections of tumor tissue. Furthermore, statistical analysis was performed in order to determine any associations among the BRAF (V600E) mutation prevalence, p53 overexpression and the clinicopathological features of PTC patients, including age, gender, tumor size, multiplicity, lymph node metastasis and extrathyroidal extension. The results revealed that the BRAF (V600E) mutation was observed in 50 (75.8%) of the 66 PTC patients and overexpression of p53 was found in 52 (78.8%) of 66 cases. No significant correlations were observed between the BRAF (V600E) mutation or p53 protein overexpression and the clinicopathological features of patients. However, the BRAF (V600E) mutation demonstrated noteworthy, but non-significant, correlations with the overexpression of p53 (P=0.0854) and extrathyroidal extension (P=0.0661). In addition, a significant correlation was observed between lymph node metastasis and bilaterality (P=0.0280). In conclusion, the present study demonstrated that the BRAF (V600E) mutation and overexpression of p53 were not significantly correlated with clinicopathological features of PTC, although notable associations were identified between BRAF (V600E) mutation and overexpression of p53 as well as extrathyroidal extension. In addition, lymph node metastasis was significantly associated with bilaterality.

PTEN and TP53 Mutations in Oncocytic Follicular Carcinoma

Oncocytic follicular carcinoma (OFC)/Hürthle cell carcinoma represents 3-4 % thyroid carcinomas and can be associated with more aggressive behavior and compromised survival compared to non-oncocytic thyroid carcinoma. In this study, we utilized targeted next-generation sequencing to investigate the molecular alterations in a heterogeneous group of clinically aggressive OFC. A total of 12 cases of OFC were included in this study. Targeted next-generation sequencing was performed using panels of 47 or 20 genes, which are frequently mutated in solid tumors. The case cohort comprised eight cases of angioinvasive OFC, two cases of poorly differentiated OFC, one case of OFC with anaplastic change, and one case of OFC with capsular invasion only. Five out of 12 cases (42 %) harbored TP53 mutation. PTEN mutations were also seen in three cases with TP53 mutation (25 %). Based on this study, TP53 and PTEN are possibly involved in the pathogenesis of OFC. Further studies on a larger case cohort are needed to further elucidate this mechanism and its effect on clinical behavior of these intriguing tumors.

Adiposity and risk of thyroid cancer: a systematic review and meta-analysis

Thyroid cancer incidence has increased rapidly over time, as has obesity prevalence. A link between the two appears plausible, but the relation of adiposity to thyroid cancer remains incompletely understood. We performed a meta-analysis of adiposity measures and thyroid cancer using studies identified through October 2014. Twenty-one articles yielded data on 12,199 thyroid cancer cases. We found a statistically significant 25% greater risk of thyroid cancer in overweight individuals and a 55% greater thyroid cancer risk in obese individuals as compared with their normal-weight peers. Each 5-unit increase in body mass index (BMI), 5 kg increase in weight, 5 cm increase in waist or hip circumference and 0.1-unit increase in waist-to-hip ratio were associated with 30%, 5%, 5% and 14% greater risks of thyroid cancer, respectively. When evaluated by histologic type, obesity was significantly positively related to papillary, follicular and anaplastic thyroid cancers, whereas it revealed an inverse association with medullary thyroid cancer. Both general and abdominal adiposity are positively associated with thyroid cancer. However, relations with BMI vary importantly by tumour histologic type.

New insights in the treatment of radioiodine refractory differentiated thyroid carcinomas: to lenvatinib and beyond

During the past two decades, several key somatic mutations associated with development and progression of differentiated thyroid cancer (DTC) have been revealed. Historically, the treatment for advanced DTC is challenging after patients become refractory to radioactive iodine. The response to doxorubicin, the only chemotherapy agent approved by the US Food and Drug Administration, is disappointing either as monotherapy or combination therapy. Because of the lack of effective systemic treatment coupled with increased understanding of molecular and cellular pathogenesis, multiple kinase inhibitors (MKIs) as an alternative therapy for the treatment of advanced DTC has generated much interest, enthusiasm, and, most excitingly, promising results. After the encouraging results of these agents in earlier trials, the Food and Drug Administration approved sorafenib for the treatment of locally recurrent, progressive, or metastatic DTC refractory to radioactive iodine treatment based on the results of a multicenter DECISION trial. Sorafenib therefore became the first MKI approved for this indication in more than 20 years. However, even more impressive responses and progression-free survival benefits were seen in the phase III SELECT trial with lenvatinib, giving even higher hopes for the future management of what was considered just a decade ago an orphan disease. Given the role of MKIs, a new era in the treatment of advanced DTC has begun. We review the key therapeutic targets, oncogenic pathways, and promising clinical results of these agents in refractory disease, as well as their roles after failure of first line kinase inhibitors.

Thyrospheres From Normal or Malignant Thyroid Tissue Have Different Biological, Functional, and Genetic Features

CONTEXT

Cancer stem cells from several human malignancies, including poorly differentiated thyroid carcinoma and thyroid cancer cell lines, have been cultured in vitro as sphere-forming cells. These thyroid cancer stem cells were proven to be able to reproduce the original tumor in a xenograft orthotopic model.

OBJECTIVES

The objective of the study was to characterize papillary thyroid carcinoma (PTC) spheres from well-differentiated thyroid cancer and normal thyroid (NT) spheres obtained from the contralateral thyroid tissue of the same patient.

DESIGN

Thyrospheres from PTCs and NTs were isolated.

MAIN OUTCOME MEASURES

Gene expression analysis by real-time PCR, immunofluorescence studies, and fluorescence-activated cell sorter analysis in thyrospheres from PTCs and NTs have been evaluated.

CONCLUSIONS

Compared with NT spheres, PTC spheres are larger, more irregular, and more clonogenic and have a higher rate of symmetric division. Moreover, PTC spheres express higher levels of stem cell markers and lower levels of thyroid-specific genes compared with NT spheres. Under appropriate conditions, NT spheres differentiated into thyrocytes, whereas PTC spheres did not, displaying a defect in the differentiation potential. Immunofluorescence experiments indicated that, in NT spheres, progenitor cells are mainly present in the sphere core, and the sphere periphery contains thyroid precursor cells already committed to differentiation. PTC spheres are not polarized like NT spheres. Unlike cells differentiated from NT spheres, TSH did not significantly stimulate cAMP production in cells differentiated from PTC spheres. A microarray analysis performed in paired samples (NT and PTC spheres from the same patient) indicated that NT and PTC spheres display a gene expression pattern typical of stem/progenitor cells; however, compared with NT spheres, PTC spheres display a unique gene expression pattern that might be involved in PTC progression.

Zn(II)-curc targets p53 in thyroid cancer cells

TP53 mutation is a common event in many cancers, including thyroid carcinoma. Defective p53 activity promotes cancer resistance to therapies and a more malignant phenotype, acquiring oncogenic functions. Rescuing the function of mutant p53 (mutp53) protein is an attractive anticancer therapeutic strategy. Zn(II)-curc is a novel small molecule that has been shown to target mutp53 protein in several cancer cells, but its effect in thyroid cancer cells remains unclear. Here, we investigated whether Zn(II)-curc could affect p53 in thyroid cancer cells with both p53 mutation (R273H) and wild-type p53. Zn(II)-curc induced mutp53H273 downregulation and reactivation of wild-type functions, such as binding to canonical target promoters and target gene transactivation. This latter effect was similar to that induced by PRIMA-1. In addition, Zn(II)-curc triggered p53 target gene expression in wild-type p53-carrying cells. In combination treatments, Zn(II)-curc enhanced the antitumor activity of chemotherapeutic drugs, in both mutant and wild-type-carrying cancer cells. Taken together, our data indicate that Zn(II)-curc promotes the reactivation of p53 in thyroid cancer cells, providing in vitro evidence for a potential therapeutic approach in thyroid cancers.

The TP53 intron 6 G13964C polymorphism and risk of thyroid and breast cancer development in the Iranian Azeri population

BACKGROUND

TP53 mutations are the most common genetic alterations in human cancers. There are also several polymorphisms in both exons and introns of TP53 that may influence its anti-tumor functions and increase the risk of cancer development. Associations of the TP53 intron 6 G13964C polymorphism with increased risk of development of several cancers have been investigated in numerous studies, but the results were controversial and conflicting. In this study, we aimed to investigate the probable association of this polymorphism with risk of both thyroid and breast cancers among the Iranian-Azeri population.

MATERIALS AND METHODS

We performed two separate case control studies on associations of the intron 6 polymorphism with two different kinds of cancer. In one case-control study, a total of 75 patients with thyroid carcinoma and 180 controls were analyzed and the other study included 170 patients with breast cancer and 135 healthy women. The intron 6 genotype was determined by RFLP-PCR and the SPSS 16 program was applied for data analysis.

RESULTS

For thyroid cancer, the frequencies of GG genotype were 96.0% in patients and 93.3% in controls. The GC genotype had a frequency of 4.0% in patients and 6.7% in controls. In the study on breast cancer, the frequency of GG and GC genotypes in patients were 95.3% and 4.7%, respectively. In breast related control group, the frequency of GG genotype was 93.3% and the frequency of GC genotype was 6.7%. None of the cases and controls had the CC genotype.

CONCLUSIONS

There was no significant association between the TP53 intron 6 G13964C polymorphism and risk of development of both thyroid and breast cancer in Iranian-Azeri patients.

Involvement of cysteine-rich protein 61 in the epidermal growth factor-induced migration of human anaplastic thyroid cancer cells

Anaplastic thyroid cancer (ATC) is among the most aggressive types of malignant cancer. Epidermal growth factor (EGF) plays a crucial role in the pathogenesis of ATC, and patients with thyroid carcinoma typically exhibit increased cysteine-rich protein 61 (Cyr61). In this study, we found that EGF treatment induced cell migration, stress fiber formation, Cyr61 mRNA and protein expressions, and Cyr61 protein secretion in ATC cells. The recombinant Cyr61 protein significantly induced cell migration; however, inhibition of Cyr61 activity by a Cyr61-specific antibody abrogated EGF-induced cell migration. EGF treatment also affected epithelial-to-mesenchymal transition (EMT)-related marker protein expression, as evidenced by an increase in vimentin and a decrease in E-cadherin expression. Inhibition of Cyr61 expression by Cyr61 siRNA decreased cell migration and reversed the EMT-related marker protein expression. EGF treatment increased the phosphorylation of the extracellular signal-regulated kinase (ERK) and cAMP response element-binding protein (CREB), and finally activated Cyr61 promoter plasmid activity. Our results suggest that Cyr61 is induced by EGF through the ERK/CREB signal pathway and that it plays a crucial role in the migration and invasion of ATC cells; moreover, Cyr61 might be a therapeutic target for metastatic ATC.

Clinicopathologic and diagnostic significance of p53 protein expression in papillary thyroid carcinoma

BACKGROUND

P53 protein expression has been detected immunohistochemically in papillary thyroid carcinoma(PTC). We investigated the relations between its expression and clinicopathologic features and its significance as a diagnostic marker.

MATERIALS AND METHODS

We compared and evaluated 93 patients in whom thyroidectomy with lymph node dissection had been performed to treat PTC for clinicopathologic significance and 102 patients with 23 papillary thyroid overt carcinomas (POC), 57 papillary thyroid microcarcinomas(PMC), 5 follicular adenomas (FA), 5 Hashimoto's thyroiditis (HT) and 12 nodular hyperplasias (NH) for significance as a diagnostic marker. Expression of p53 protein was evaluated immunohistochemically in sections of paraffin- embedded tissue.

RESULTS

Statistical analysis showed significantly different expression of p53 in PTC versus other benign thyroid lesions (BTL).The diagnostic sensitivity and specificity were 85.0% and 72.7%, respectively. Overexpression of p53 protein was observed in 44 of the 93 PTC cases (47.3%), but no significant correlation between p53 protein overexpression and clinicopathologic features (age, size, multiplicity, lymph node metastasis, extrathyroidal extension and vascular invasion) was noted.

CONCLUSIONS

p53 is valuable to distinguish PTC from other BTL, but there is no correlation between p53 protein overexpression and clinicopathologic features.

"Is there any association between insulin resistance and thyroid cancer? : A case control study"

Insulin stimulates proliferation of thyroid cells in culture. The presence of insulin resistance (IR) is associated with larger thyroid gland volume and an increased prevalence of thyroid nodules. The aim of this study was to investigate the presence of any possible association between IR and thyroid cancer. Forty-one patients with diffuse thyroid cancer (Group 1) were matched for age and gender with 41 patients with nodular goiter (Group 2). Both groups were compared in terms of frequency of IR, as estimated by the homeostasis model assessment, as well as other parameters of the metabolic syndrome (MetS). Fourteen patients (34.1 %) in each group had MetS. Twelve patients (29.3 %) in group 1 had IR compared to 10 (24.4 %) in group 2. Mean HOMA-IR scores in group 1 and 2 were 2.5 ± 2.2 and 1.8 ± 1.1, respectively. Thirty-two patients (78 %) in group 1 had a body mass index (BMI) of more than 25 compared to 33 patients (80.5 %) in group 2. The difference between groups with regard to HOMA-IR, the frequency of IR, BMI, and any of the parameters of MetS was statistically insignificant (p > 0.05). A subgroup analysis based on tumor size did not reveal a significant difference between patients with microcarcinoma (≤10 mm) and macrocarcinoma (>10 mm) in terms of any of the study parameters (p > 0.05). Neither MetS nor IR was a significant risk factor for thyroid cancer following logistic regression analysis (p > 0.05). IR is not more prevalent in patients with thyroid cancer. Some other pathologic mechanisms may be more prominent during thyroid carcinogenesis.

Diabetes and thyroid cancer risk: literature review

Diabetic patients have a higher risk of various types of cancer. However, whether diabetes may increase the risk of thyroid cancer has not been extensively studied. This paper reviews and summarizes the current literature studying the relationship between diabetes mellitus and thyroid cancer, and the possible mechanisms linking such an association. Epidemiologic studies showed significant or nonsignificant increases in thyroid cancer risk in diabetic women and nonsignificant increase or no change in thyroid cancer risk in diabetic men. A recent pooled analysis, including 5 prospective studies from the USA, showed that the summary hazard ratio (95% confidence interval) for women was 1.19 (0.84-1.69) and was 0.96 (0.65-1.42) for men. Therefore, the results are controversial and the association between diabetes and thyroid cancer is probably weak. Further studies are necessary to confirm their relationship. Proposed mechanisms for such a possible link between diabetes and thyroid cancer include elevated levels of thyroid-stimulating hormone, insulin, glucose and triglycerides, insulin resistance, obesity, vitamin D deficiency, and antidiabetic medications such as insulin or sulfonylureas.

The treatment of differentiated thyroid cancer in children: emphasis on surgical approach and radioactive iodine therapy

Pediatric thyroid cancer is a rare disease with an excellent prognosis. Compared with adults, epithelial-derived differentiated thyroid cancer (DTC), which includes papillary and follicular thyroid cancer, presents at more advanced stages in children and is associated with higher rates of recurrence. Because of its uncommon occurrence, randomized trials have not been applied to test best-care options in children. Even in adults that have a 10-fold or higher incidence of thyroid cancer than children, few prospective trials have been executed to compare treatment approaches. We recognize that treatment recommendations have changed over the past few decades and will continue to do so. Respecting the aggressiveness of pediatric thyroid cancer, high recurrence rates, and the problems associated with decades of long-term follow-up, a premium should be placed on treatments that minimize risk of recurrence and the adverse effects of treatments and facilitate follow-up. We recommend that total thyroidectomy and central compartment lymph node dissection is the surgical procedure of choice for children with DTC if it can be performed by a high-volume thyroid surgeon. We recommend radioactive iodine therapy for remnant ablation or residual disease for most children with DTC. We recommend long-term follow-up because disease can recur decades after initial diagnosis and therapy. Considering the complexity of DTC management and the potential complications associated with therapy, it is essential that pediatric DTC be managed by physicians with expertise in this area.

Managing anaplastic thyroid carcinoma

Anaplastic thyroid cancer is one of the most lethal malignancies, with dismal prognosis, resistance to multimodal treatments and a median survival of only 5-6 months. Advances in the discovery of genetic pathway aberrations involved in this aggressive disease have been made, and multiple novel therapies targeting these pathways are undergoing clinical trials. So far, there is no single effective treatment for this disease; however, multimodal therapies with a combination of surgery, radiation and chemotherapy hold some promise. We conducted a PubMed search using the words thyroid neoplasm, anaplastic thyroid carcinoma, anaplastic thyroid cancer and anaplastic thyroid neoplasm, revealing 1673 publications. We review the pathophysiology, current treatments and advances made in identifying the alterations in genetic pathways, as well as novel therapies targeting these pathways.

Lovastatin inhibits proliferation of anaplastic thyroid cancer cells through up-regulation of p27 by interfering with the Rho/ROCK-mediated pathway

Previously, we demonstrated that lovastatin, a HMG-CoA reductase inhibitor, induced apoptosis, differentiation, and inhibition of invasiveness of human anaplastic thyroid carcinoma cells (ATCs). Here, we further examined the effect of lovastatin on the growth of ARO cells. Lovastatin (0-20μM) concentration-dependently decreased cell number in cultured ATC and arrested the cell at the G0/G1 phase of the cell cycle. Western blot analysis revealed that lovastatin caused an increase of the protein level of p27 and cyclin-dependent kinase (CDK)4 and a decrease of the protein level of cyclin A2, cyclin D3, and phosphorylated Rb (pRb), but did not significantly change the protein levels of p21, cyclins D1 and E, and CDK2, in ARO cells. The formation of the CDK2-p27 complex was increased and the CDK2 activity was decreased in the lovastatin-treated ARO cells. Pretreatment of ARO cells with a p27, but not p21, antisense oligonucleotide prevented the lovastatin-induced G0/G1 arrest in ARO cells. The lovastatin-induced growth inhibition and translocation of RhoA and Rac1 in ARO cells were completely prevented by mevalonate and partially by geranylgeranyl pyrophosphate. Treatment of ARO cells with Y27632, an inhibitor of Rho-associated kinase, abolished the GGPP-mediated prevention of lovastatin-induced anti-proliferation and up-regulation and prolonged degradation of p27. Taken together, these data suggest that lovastatin treatment caused a reduction of Rho geranylgeranylation, which in turn increased the expression and stability of p27, and then inhibited ARO cell proliferation. These data suggest that lovastatin merits further investigation as multipotent therapy for treatment ATC.

Diabetes and thyroid cancer risk in the National Institutes of Health-AARP Diet and Health Study

BACKGROUND

We hypothesized that diabetes may play a role in thyroid cancer risk due to the parallel secular rise in diabetes prevalence and morbidity in the United States, the higher prevalence of thyroid disorders among diabetics compared with the general population, and the potential roles of metabolic syndrome, obesity, and diabetes as precipitating factors in cancer development.

METHODS

We assessed the association between self-reported diabetes and the risk of differentiated thyroid cancer in the NIH-AARP Diet and Health Study, a prospective cohort of 200,556 women and 295,992 men, 50-71 years of age, in 1995-1996. Diabetes status and information on potential confounders was ascertained using a self-administered questionnaire. During an average of 10 years of follow-up, 585 thyroid cancer cases were identified. Cox proportional hazards models were used to estimate hazard ratios (HR) and 95% confidence intervals (CI) for thyroid cancer and thyroid cancer subtypes in men and women according to diabetes status.

RESULTS

Nine percent of the total baseline cohort reported a history of diabetes (7% of women, 10% of men). A nonsignificant 25% increase in thyroid cancer risk (HR = 1.25; 95% CI: 0.95-1.64) was associated with diabetes. Among women, the risk was significantly increased (HR = 1.46, 95% CI: 1.01-2.10). The risk was not elevated among men (HR = 1.04, 95% CI: 0.69-1.58). In this cohort, diabetic women with differentiated thyroid cancer were at somewhat higher risk of follicular thyroid cancer (HR = 1.92; 95% CI: 0.86-4.27) than papillary thyroid cancer (HR = 1.25; 95% CI: 0.80-1.97).

CONCLUSION

This study lends support to the hypothesis that diabetes increases the risk of differentiated thyroid cancer.