Sporadic Medullary Thyroid Carcinoma: Towards a Precision Medicine

Hand-foot syndrome in sorafenib and lenvatinib treatment for advanced thyroid cancer

Objective

The aim of this study was to assess the clinical impact of hand-foot syndrome (HFS) during treatment with two multikinase inhibitors, sorafenib and lenvatinib, in a large group of patients with advanced thyroid cancer. Moreover, we looked for possible associations between HFS occurrence and clinical and pathological features.

Methods

We retrospectively evaluated 239 patients with advanced thyroid cancer: 165 treated with lenvatinib and 74 with sorafenib. Statistical analyses were performed to verify which features could be correlated with HFS development.

Results

HFS was observed in 35/74 (47.4%) and in 43/165 (26.7%) patients treated with sorafenib or lenvatinib, respectively. The median latency from the drug beginning and HFS appearance was 27 days for sorafenib and 2.9 months for lenvatinib. G3/G4 toxicity was observed in 16/35 (45.7%) patients treated with sorafenib and only in 3/43 (7%) treated with lenvatinib. Drug dose reduction due to HFS was required in 19/74 (25.7%) and 3/165 (1.8%) patients treated with sorafenib and lenvatinib, respectively. HFS occurrence was significantly associated with a longer duration of therapy in both groups.

Conclusion

HFS was a frequent adverse event during both lenvatinib and sorafenib therapy, with a higher frequency and toxicity grade during sorafenib treatment. HFS was the most frequent reason for drug reduction or discontinuation in patient treated with sorafenib. Early diagnosis of HFS is important to allow early intervention, possibly in a multidisciplinary setting, and to avoid treatment discontinuation, which is highly relevant to obtain the maximum effectiveness of systemic therapy.

Paraneoplastic Diarrhea From Medullary Thyroid Carcinoma Resolved With Yttrium-90 Radioembolization of Liver Metastases

Medullary thyroid carcinoma (MTC) can often have an indolent course despite distant metastatic disease. Additionally, given that metastatic MTC is incurable and systemic therapies have non-negligeable toxicities, localized treatments are often favored in presence of oligo-progressive disease. Transarterial radioembolization (TARE) with yttrium-90 (Y90) has emerged as a safe and efficacious treatment for nonresectable primary and metastatic liver tumors, yet data supporting its use in metastatic MTC are limited. We present the case of a patient with hereditary MTC and large bilobar liver metastases who demonstrated tumor response and resolution of their paraneoplastic diarrhea following TARE with Y90 microspheres.

The Role of Lipid Metabolism Disorders in the Development of Thyroid Cancer

Thyroid cancer (TC) is a neoplasm with an increasing incidence worldwide. Its etiology is complex and based on a multi-layered interplay of factors. Among these, disorders of lipid metabolism have emerged as an important area of investigation. Cancer cells are metabolically reprogrammed to promote their rapid growth, proliferation, and survival. This reprogramming is associated with significant changes at the level of lipids, mainly fatty acids (FA), as they play a critical role in maintaining cell structure, facilitating signaling pathways, and providing energy. These lipid-related changes help cancer cells meet the increased demands of continued growth and division while adapting to the tumor microenvironment. In this review, we examine lipid metabolism at different stages, including synthesis, transport, and oxidation, in the context of TC and the effects of obesity and hormones on TC development. Recent scientific efforts have revealed disturbances in lipid homeostasis that are specific to thyroid cancer, opening up potential avenues for early detection and targeted therapeutic interventions. Understanding the intricate metabolic pathways involved in FA metabolism may provide insights into potential interventions to prevent cancer progression and mitigate its effects on surrounding tissues.

Efficacy and safety of selpercatinib in treating RET-altered MTC: A single-arm meta-analysis

Background

Selpercatinib is effective in the treatment of RET-altered medullary thyroid carcinoma (MTC). This study aimed to evaluate the efficacy and safety of selpercatinib in the treatment of patients with RET-altered MTC.

Methods

PubMed, Embase, the Cochrane Library, and ClinicalTrials.gov were searched from their inception to April 5, 2024. Outcomes included complete response (CR), partial response (PR), stable disease (SD), objective response rate (ORR), disease control rate (DCR), and adverse events (AEs). We carried out a meta-analysis of these studies and exploratory subgroup analyses. The effect sizes for all pooled results were presented as 95% confidence intervals with upper and lower limits.

Results

The pooled CR, PR, and SD rates for all patients were 10%, 59%, and 26%, respectively. The pooled ORR in all patients was 70%, while the pooled ORR in pre-treated and non-pre-treated groups were 67% and 70%, respectively. The pooled DCR in all patients was 95%, while the pooled DCR in pre-treated and non-pre-treated groups were 96% and 95%, respectively. The most common AEs associated with selpercatinib were hypertension, alanine aminotransferase (ALT) increased and aspartate aminotransferase (AST) increased.

Conclusion

Selpercatinib offers significant benefits to patients with RET-altered MTC with assessable CR, PR, SD, ORR, and grade 3-4 AEs; however, treatment-related AEs should be considered.

Timing and Ideal Patient for an Appropriate Search for Somatic RET Mutation in Medullary Thyroid Cancer

RET somatic mutation analysis in sporadic MTC should be guided by postoperative evaluation results.

Machine Learning for Predicting Distant Metastasis of Medullary Thyroid Carcinoma Using the SEER Database

Objectives

We aimed to establish an effective machine learning (ML) model for predicting the risk of distant metastasis (DM) in medullary thyroid carcinoma (MTC).

Methods

Demographic data of MTC patients were extracted from the Surveillance, Epidemiology, and End Results (SEER) database of the National Institutes of Health between 2004 and 2015 to develop six ML algorithm models. Models were evaluated based on accuracy, precision, recall rate, F1-score, and area under the receiver operating characteristic curve (AUC). The association between clinicopathological characteristics and target variables was interpreted. Analyses were performed using traditional logistic regression (LR).

Results

In total, 2049 patients were included and 138 developed DM. Multivariable LR showed that age, sex, tumor size, extrathyroidal extension, and lymph node metastasis were predictive features for DM in MTC. Among the six ML models, the random forest (RF) had the best predictability in assessing the risk of DM in MTC, with an accuracy, precision, recall rate, F1-score, and AUC higher than those of the traditional binary LR model.

Conclusion

RF was superior to traditional LR in predicting the risk of DM in MTC and can provide a valuable reference for clinicians in decision-making.

Early postoperative prediction of the risk of distant metastases in medullary thyroid cancer

Purpose

The purpose of this study was to develop and validate a nomogram for estimating the risk of distant metastases (DM) in the early postoperative phase of medullary thyroid cancer (MTC).

Patients and methods

We retrospectively reviewed cases of patients diagnosed with MTC from the Surveillance, Epidemiology, and End Results (SEER) database from 2007 to 2017. In addition, we gathered data on patients who diagnosed as MTC at Department of Thyroid Surgery in the First Hospital of Jilin University between 2009 and 2021. Four machine learning algorithms were used for modeling, including random forest classifier (RFC), gradient boosting decision tree (GBDT), logistic regression (LR), and support vector machine (SVM). The optimal model was selected based on accuracy, recall, specificity, receiver operating characteristic curve (ROC), and area under curve (AUC). After that, the Hosmer-Lemeshow goodness-of-fit test, the brier score (BS) and calibration curve were used for validation of the best model, which allowed us to measure the discrepancy between the projected value and the actual value.

Results

Through feature selection, we finally clarified that the following four features are associated with distant metastases of MTC, which are age, surgery, primary tumor (T) and nodes (N). The AUC values of the four models in the internal test set were as follows: random forest: 0.8786 (95% CI, 0.8070-0.9503), GBDT: 0.8402 (95% CI, 0.7606-0.9199), logistic regression: 0.8670(95%CI,0.7927-0.9413), and SVM: 0.8673 (95% CI, 0.7931-0.9415). As can be shown, there was no statistically significant difference in their AUC values. The highest AUC value of the four models were chosen as the best model since. The model was evaluated on the internal test set, and the accuracy was 0.84, recall was 0.76, and specificity was 0.87. The ROC curve was drawn, and the AUC was 0.8786 (95% CI, 0.8070-0.9503), which was higher than the other three models. The model was visualized using the nomogram and its net benefit was shown in both the Decision Curve Analysis (DCA) and Clinical Impact Curve (CIC).

Conclusion

Proposed model had good discrimination ability and could preliminarily screen high-risk patients for DM in the early postoperative period.

Exploring blood metabolites and thyroid disorders: a bidirectional mendelian randomization study

Background

Human blood metabolites have demonstrated close associations with thyroid disorders in observational studies. However, it's essential to determine whether these correlations imply causation. Mendelian Randomization (MR) offers a promising approach to investigate these patterns.

Aims

The primary aim of our investigation is to establish causality between blood metabolites and three thyroid disorders: TC, GD, and HT.

Methods

We employed a two-sample bidirectional MR analysis approach to assess the relationships between 452 blood metabolites and the three aforementioned thyroid disorders. Causal links were estimated using the IVW method, with sensitivity analyses conducted via MR-Egger, Weighted Median, and MR-PRESSO. We assessed potential heterogeneity and pleiotropy using MR-Egger intercept and Cochran's Q statistic. Additionally, we conducted pathway analysis to identify potential metabolic pathways.

Results

We found 46 metabolites that showed suggestive associations with thyroid disease risk, especially Aspartate (ORIVW=7.41; 95%CI: 1.51-36.27; PIVW=0.013) and C-glycosyltryptophan (ORIVW=0.04; 95%CI: 0.00-0.29; PIVW=0.001) impacted TC, Kynurenine (ORIVW=2.69; 95%CI: 1.08-6.66; PIVW=0.032) and 4-androsten-3beta,17beta-diol disulfate 2 (ORIVW=0.78; 95%CI: 0.48-0.91; PIVW=0.024) significantly impacted GD, and Alpha-ketoglutarate (ORIVW=46.89; 95%CI: 4.65-473.28; PIVW=0.001) and X-14189-leucylalanine (ORIVW=0.31; 95%CI: 0.15-0.64 PIVW=0.001) significantly impacted HT. We also detected 23 metabolites influenced by TC and GD. Multiple metabolic pathways have been found to be involved in thyroid disease.

Conclusion

Our MR findings suggest that the identified metabolites and pathways can serve as biomarkers for clinical thyroid disorder screening and prevention, while also providing new insights for future mechanistic exploration and drug target selection.

From Circulating Tumor Cells to Mirna: New Challenges in the Diagnosis and Prognosis of Medullary Thyroid Cancer

Medullary thyroid carcinoma (MTC) is a malignant tumor that arises from parafollicular C cells, which are responsible for producing calcitonin. The majority (75%) of MTC cases are sporadic forms, while the remaining (25%) have a hereditary component. In these hereditary cases, MTC can occur in conjunction with other endocrine disorders (i.e., pheochromocytoma) or as an isolated condition known as familial medullary thyroid carcinoma. The primary genetic mutation associated with the development of MTC, regardless of its hereditary or sporadic nature, is a point mutation in the RET gene. Evaluation of serum calcitonin levels represents the most reliable and sensitive marker for both the initial diagnosis and the postsurgical monitoring of MTC. Unfortunately, most patients do not achieve normalization of postsurgical serum calcitonin (CT) levels after surgery. Therefore, there is a need to find new biomarkers to be used with serum CT in order to increase test sensitivity and specificity. In this review, we summarize the literature from 2010 to 2023 to review the role of circulating tumor cells, cell-free DNA, and miRNA and their application in diagnosis, outcome of MTC, and response to treatments.

Genetically engineered mouse models of head and neck cancers

The head and neck region is one of the anatomic sites commonly afflicted by cancer, with ~1.5 million new diagnoses reported worldwide in 2020 alone. Remarkable progress has been made in understanding the underlying disease mechanisms, personalizing care based on each tumor's individual molecular characteristics, and even therapeutically exploiting the inherent vulnerabilities of these neoplasms. In this regard, genetically engineered mouse models (GEMMs) have played an instrumental role. While progress in the development of GEMMs has been slower than in other major cancer types, several GEMMs are now available that recapitulate most of the heterogeneous characteristics of head and neck cancers such as the tumor microenvironment. Different approaches have been employed in GEMM development and implementation, though each can generally recapitulate only certain disease aspects. As a result, appropriate model selection is essential for addressing specific research questions. In this review, we present an overview of all currently available head and neck cancer GEMMs, encompassing models for head and neck squamous cell carcinoma, nasopharyngeal carcinoma, and salivary and thyroid gland carcinomas.

Clinical Evolution of Sporadic Medullary Thyroid Carcinoma With Biochemical Incomplete Response After Initial Treatment

CONTEXT

The clinical response after surgery is a determinant in the management of patients with medullary thyroid carcinoma (MTC). In case of excellent or structural incomplete response, the follow-up strategies are well designed. Conversely, in case of biochemical incomplete response (BiR) the management is not clearly defined.

OBJECTIVE

This work aimed to evaluate the overall and per-site prevalence of structural disease detection in sporadic MTC patients with BiR and to assess the predictive value of various clinical, biochemical, and genetic features.

METHODS

We evaluated data of 599 consecutive patients surgically treated for sporadic MTC (2000-2018) and followed-up at the endocrine unit of the University Hospital of Pisa.

RESULTS

After a median of 5 months from surgery, 145 of 599 (24.2%) patients were classified as BiR. Structural disease was detected in 64 of 145 (44.1%), after a median time of 3.3 years. In 73.6%, structural disease was detected at a single site, prevalently cervical lymph nodes. Among several others, at the time of first evaluation after surgery, only basal calcitonin (bCTN) and stage IVa/b were independent predictive factors. Also, structural disease was more frequent in patients with shorter CTN doubling time and somatic RET mutation.

CONCLUSION

In sporadic MTC patients with BiR, the risk of detection of structural disease was about 50% at 10 years. Higher bCTN levels and staging predicted the risk of detecting structural disease. According to these findings, stricter follow-up should be reserved for MTC with BiR and elevated values of bCTN and to those with an advanced stage. Long follow-up should be considered for all BiR patients since 50% of them develop structural disease within 10 years.

Molecular basis and targeted therapy in thyroid cancer: Progress and opportunities

Thyroid cancer (TC) is the most prevalent endocrine malignant tumor. Surgery, chemotherapy, radiotherapy, and radioactive iodine (RAI) therapy are the standard TC treatment modalities. However, recurrence or tumor metastasis remains the main challenge in the management of anaplastic thyroid cancer (ATC) and radioiodine (RAI) radioactive iodine-refractory differentiated thyroid cancer (RR-DTC). Several multi-tyrosine kinase inhibitors (MKIs), or immune checkpoint inhibitors in combination with MKIs, have emerged as novel therapies for controlling the progression of DTC, medullary thyroid cancer (MTC), and ATC. Here, we discuss and summarize the molecular basis of TC, review molecularly targeted therapeutic drugs in clinical research, and explore potentially novel molecular therapeutic targets. We focused on the evaluation of current and recently emerging tyrosine kinase inhibitors approved for systemic therapy for TC, including lenvatinib, sorafenib and cabozantinib in DTC, vandetanib, cabozantinib, and RET-specific inhibitor (selpercatinib and pralsetinib) in MTC, combination dabrafenib with trametinib in ATC. In addition, we also discuss promising treatments that are in clinical trials and may be incorporated into clinical practice in the future, briefly describe the resistance mechanisms of targeted therapies, emphasizing that personalized medicine is critical to the design of second-line therapies.

Using preoperative ultrasound vascularity characteristics to estimate medullary thyroid cancer

BACKGROUND

The early diagnosis of medullary thyroid carcinoma (MTC) is still a challenge in clinical practice. Based on ultrasound features, many MTC cases without suspicious characteristics are not categorized as high risk for malignancy. This study was designed to comprehensively investigate the ultrasonic features of MTC on ultrasound and help identify thyroid nodules with a high risk of MTC.

METHODS

Between 2017 and 2023, we retrospectively reviewed 116 consecutive thyroid nodules with a histologic diagnosis of MTC who had undergone preoperative ultrasound examination. According to the ultrasonic criteria for risk classification, nodules were classified as "ultrasound-high suspicious" (h-MTC) and "ultrasound-low suspicious" (l-MTC). Using the same database, a tumour size- and risk evaluation-matched control group comprising 62 lesions was randomly selected to compare the vascularity features of l-MTC disease.

RESULTS

We identified 85 h-MTC nodules (73.3%) and 31 l-MTC nodules (26.7%). For patients with l-MTC disease, 22/31 (71.0%) of the lesions were followed up for a period before fine needle aspiration (FNA) or surgery. We observed more penetrating branching vascularity in the l-MTC group than in the benign nodule group (23/31, 74.2% vs. 5/59, 4.8%, P < 0.001). We also showed that more CHAMMAS IV patterns (central blood flow greater than perinodular flow) (87.1% vs. 32.3%, P < 0.001)) and CHEN IV patterns (penetrating vascularity) (100% vs. 25.8%, P < 0.001) were found in l-MTC than benign nodules.

CONCLUSIONS

Vascularity features can help differentiate l-MTC from benign nodules; moreover, we report a novel sonographic vascularity pattern of l-MTC disease, penetrating branching vascularity. The utilization of vascularity features will help to identify MTC among nodules with low-intermediate suspicion by ultrasound risk classification to ensure appropriate clinical management.

Integrated analysis of transcription factor-mRNA-miRNA regulatory network related to immune characteristics in medullary thyroid carcinoma

Background

Medullary thyroid carcinoma (MTC), a thyroid C cell-derived malignancy, is poorly differentiated and more aggressive than papillary, follicular and oncocytic types of thyroid cancer. The current therapeutic options are limited, with a third of population suffering resistance. The differential gene expression pattern among thyroid cancer subtypes remains unclear. This study intended to explore the exclusive gene profile of MTC and construct a comprehensive regulatory network via integrated analysis, to uncover the potential key biomarkers.

Methods

Multiple datasets of thyroid and other neuroendocrine tumors were obtained from GEO and TCGA databases. Differentially expressed genes (DEGs) specific in MTC were identified to construct a transcription factor (TF)-mRNA-miRNA network. The impact of the TF-mRNA-miRNA network on tumor immune characteristics and patient survival was further explored by single-sample GSEA (ssGSEA) and ESTIMATE algorithms, as well as univariate combined with multivariate analyses. RT-qPCR, cell viability and apoptosis assays were performed for in vitro validation.

Results

We identified 81 genes upregulated and 22 downregulated in MTC but not in other types of thyroid tumor compared to the normal thyroid tissue. According to the L1000CDS2 database, potential targeting drugs were found to reverse the expressions of DEGs, with panobinostat (S1030) validated effective for tumor repression in MTC by in vitro experiments. The 103 DEGs exclusively seen in MTC were involved in signal release, muscle contraction, pathways of neurodegeneration diseases, neurotransmitter activity and related amino acid metabolism, and cAMP pathway. Based on the identified 15 hub genes, a TF-mRNA-miRNA linear network, as well as REST-cored coherent feed-forward loop networks, namely REST-KIF5C-miR-223 and REST-CDK5R2-miR-130a were constructed via online prediction and validation by public datasets and our cohort. Hub-gene, TF and miRNA scores in the TF-mRNA-miRNA network were related to immune score, immune cell infiltration and immunotherapeutic molecules in MTC as well as in neuroendocrine tumor of lung and neuroblastoma. Additionally, a high hub-gene score or a low miRNA score indicated good prognoses of neuroendocrine tumors.

Conclusion

The present study uncovers underlying molecular mechanisms and potential immunotherapy-related targets for the pathogenesis and drug discovery of MTC.

Establishment and validation of a nomogram model for predicting distant metastasis in medullary thyroid carcinoma: An analysis of the SEER database based on the AJCC 8th TNM staging system

OBJECTIVE

Medullary thyroid carcinoma (MTC) patients with distant metastases frequently present a relatively poor survival prognosis. Our main purpose was developing a nomogram model to predict distant metastases in MTC patients.

METHODS

This was a retrospective study based on the Surveillance, Epidemiology, and End Results (SEER) database. Data of 807 MTC patients diagnosed from 2004 to 2015 who undergone total thyroidectomy and neck lymph nodes dissection was included in our study. Independent risk factors were screened by univariate and multivariate logistic regression analysis successively, which were used to develop a nomogram model predicting for distant metastasis risk. Further, the log-rank test was used to compare the differences of Kaplan-Meier curves of cancer-specific survival (CSS) in different M stage and each independent risk factor groups.

RESULTS

Four clinical parameters including age > 55 years, higher T stage (T3/T4), higher N stage (N1b) and lymph node ratio (LNR) > 0.4 were significant for distant metastases at the time of diagnosis in MTC patients, and were selected to develop a nomogram model. This model had satisfied discrimination with the AUC and C-index of 0.894, and C-index was confirmed to be 0.878 through bootstrapping validation. A decision curve analysis (DCA) was subsequently made to evaluate the feasibility of this nomogram for predicting distant metastasis. In addition, CSS differed by different M stage, T stage, N stage, age and LNR groups.

CONCLUSIONS

Age, T stage, N stage and LNR were extracted to develop a nomogram model for predicting the risk of distant metastases in MTC patients. The model is of great significance for clinicians to timely identify patients with high risk of distant metastases and make further clinical decisions.

Chylous effusions in advanced medullary thyroid cancer patients treated with selpercatinib

OBJECTIVE

Selpercatinib is a highly selective RET-inhibitor drug, approved for the treatment of RET-altered lung and thyroid cancers. So far, RET-altered medullary thyroid cancer (MTC) patients treated with selpercatinib showed a remarkable objective response rate and safety profile. However, new treatment emerging adverse events (TEAEs) have been recently reported. The aim of this study was to evaluate the prevalence, features, and clinical management of effusions that are one of these TEAEs.

DESIGN

Around 10 of 11 patients with advanced MTC enrolled in the LIBRETTO-201 clinical trial at Endocrinology Unit of the Pisa University Hospital were evaluated for the presence and management of effusions.

METHODS

We retrospectively evaluated MTC patients treated with selpercatinib. The presence of pleural, pericardial, abdominal, and/or pelvic effusions was evaluated by reviewing the computerized tomography scan performed during the study protocol and up to 24 months of observation.

RESULTS

All but one MTC patient experienced previous multikinase inhibitors treatment. Three patients already had effusions before starting selpercatinib treatment. New effusions appeared in eight of ten (80%) patients during the treatment. A chylous nature was documented in patients who underwent fluid aspiration. Whenever a dose reduction was performed, a significant positive effect was observed.

CONCLUSIONS

Chylous effusions are a new TEAE of selpercatinib treatment. They can appear or worsen at any time during the treatment. For cases with asymptomatic and mild effusions, active surveillance may be appropriate and safe. In symptomatic and/or moderate/severe cases, aspiration of the fluid and a dose reduction can improve this AE, strongly supporting a cause-effect correlation with selpercatinib.

SIGNIFICANCE STATEMENT

Effusions, particularly of chylous nature, represent emergent and quite frequent adverse events in the management of patients affected by advanced MTC on treatment with the highly selective inhibitor selpercatinib. In this study, we evaluated, in a series of MTC patients treated with selpercatinib, the prevalence of pleural, pericardial, abdominal, and/or pelvic effusions. Insights into the diagnosis and treatment of the effusions are provided as well as suggestions for clinical management.

RET Proto-Oncogene-Not Such an Obvious Starting Point in Cancer Therapy

Mutations and fusions of RET (rearranged during transfection) gene are detected in a few common types of tumors including thyroid or non-small cells lung cancers. Multiple kinase inhibitors (MKIs) do not show spectacular effectiveness in patients with RET-altered tumors. Hence, recently, two novel RET-specific inhibitors were registered in the US and in Europe. Selpercatinib and pralsetinib showed high efficacy in clinical trials, with fewer adverse effects, in comparison to previously used MKIs. However, the effectiveness of these new drugs may be reduced by the emergence of resistance mutations in RET gene and activation of different activating signaling pathways. This review presents the function of the normal RET receptor, types of molecular disturbances of the RET gene in patients with various cancers, methods of detecting these abnormalities, and the effectiveness of modern anticancer therapies (ranging from immunotherapies, through MKIs, to RET-specific inhibitors).

Modulatory role of miRNAs in thyroid and breast cancer progression and insights into their therapeutic manipulation

Over the past few decades, thyroid cancer has become one of the most common types of endocrine cancer, contributing to an increase in prevalence. In the year 2020, there were 586,202 newly diagnosed cases of thyroid cancer around the world. This constituted approximately 3.0% of all patients diagnosed with cancer. The World Health Organization reported that there will be 2.3 million women receiving treatment for breast cancer in 2020, with 685,000. Despite the fact that carcinoma is one of the world's leading causes of death, there is still a paucity of information about its biology. MicroRNAs (miRNAs; miRs) are non-coding RNAs that can reduce gene expression by cleaving the 3' untranslated regions of mRNA. These factors make them a potential protein translation inhibitor. Diverse biological mechanisms implicated in the genesis of cancer are modulated by miRNA. The investigation of global miRNA expression in cancer showed regulatory activity through up regulation and down-regulation in several cancers, including thyroid cancer and breast cancer. In thyroid cancer, miRNA influences several cancers related signaling pathways through modulating MAPK, PI3K, and the RAS pathway. In breast cancer, the regulatory activity of miRNA was played through the cyclin protein family, protein kinases and their inhibitors, and other growth promoters or suppressors, which modulated cell proliferation and cell cycle progression. This article's goal is to discuss key miRNA expressions that are involved in the development of thyroid and breast cancer as well as their therapeutic manipulation for these two specific cancer types.

Preclinical Evaluation of Novel Tyrosine-Kinase Inhibitors in Medullary Thyroid Cancer

Simple Summary

Medullary thyroid carcinoma (MTC) is a neuroendocrine tumor arising from parafollicular calcitonin-secreting C cells of the thyroid. Most of the patients affected by MTC, especially the familial form, harbor a mutation of the RET proto-oncogene. In patients with advanced disease, medical therapy is represented by two tyrosine-kinase inhibitors: cabozantinib and vandetanib. However, their usage is limited by several adverse events and drug-resistance onset. The aim of this preclinical study was to evaluate the antitumor activity of novel molecules for the therapy of MTC: SU5402, an inhibitor of the fibroblast growth factor receptor type 1 (FGFR-1) and vascular endothelial growth factor receptor (VEGFR)-2; sulfatinib, a multi-target kinase inhibitor selective for FGFR-1 and the VEGFR-1, -2, and -3; SPP86, a RET-specific inhibitor. Our results suggest a potential role in targeting the FGFR and VEGFR signaling pathways as an alternative strategy for resistant tumors and a significative antitumor activity of this new RET-specific inhibitor.

Abstract

Medullary thyroid carcinoma (MTC) is a neuroendocrine tumor arising from parafollicular C cells of the thyroid gland. In this preclinical study, we tested three tyrosine-kinase inhibitors (TKIs): SU5402, a selective inhibitor of fibroblast growth factor receptor (FGFR)-1 and vascular endothelial growth factor receptor (VEGFR)-2; sulfatinib, an inhibitor of FGFR-1 and VEGFR-1, -2, -3; and SPP86, a RET-specific inhibitor. The effects of these compounds were evaluated in vitro in two human MTC cell lines (TT and MZ-CRC-1), and in vivo using xenografts of MTC cells in zebrafish embryos. SU5402, sulfatinib and SPP86 decreased cell viability. Sulfatinib and SPP86 significantly induced apoptosis in both cell lines. Sulfatinib and SPP86 inhibited the migration of TT and MZCRC-1 cells, while SU5402 was able to inhibit migration only in TT cells. In vivo we observed a significant reduction in TT cell-induced angiogenesis in zebrafish embryos after incubation with sulfatinib and SPP86. In conclusion, sulfatinib and SPP86 displayed a relevant antitumor activity both in vitro and in vivo. Moreover, this work suggests the potential utility of targeting FGFR and VEGFR signaling pathways as an alternative therapy for MTC.

Update on the Diagnosis and Management of Medullary Thyroid Cancer: What Has Changed in Recent Years?

Medullary thyroid carcinoma (MTC) is a neoplasm originating from parafollicular C cells. MTC is a rare disease, but its prognosis is less favorable than that of well-differentiated thyroid cancers. To improve the prognosis of patients with MTC, early diagnosis and prompt therapeutic management are crucial. In the following paper, recent advances in laboratory and imaging diagnostics and also pharmacological and surgical therapies of MTC are discussed. Currently, a thriving direction of development for laboratory diagnostics is immunohistochemistry. The primary imaging modality in the diagnosis of MTC is the ultrasound, but opportunities for development are seen primarily in nuclear medicine techniques. Surgical management is the primary method of treating MTCs. There are numerous publications concerning the stratification of particular lymph node compartments for removal. With the introduction of more effective methods of intraoperative parathyroid identification, the complication rate of surgical treatment may be reduced. The currently used pharmacotherapy is characterized by high toxicity. Moreover, the main limitation of current pharmacotherapy is the development of drug resistance. Currently, there is ongoing research on the use of tyrosine kinase inhibitors (TKIs), highly specific RET inhibitors, radiotherapy and immunotherapy. These new therapies may improve the prognosis of patients with MTCs.

The Role of the Kinase Inhibitors in Thyroid Cancers

Thyroid cancer is the most common endocrine malignancy, accounting for about 3% of all cancer cases each year worldwide with increasing incidence, but with the mortality remaining stable at low levels. This contradiction is due to overdiagnosis of indolent neoplasms identified by neck ultrasound screening that would remain otherwise asymptomatic. Differentiated thyroid carcinomas (DTCs) are almost curable for 95% with a good prognosis. However, 5% of these tumours worsened toward aggressive forms: large tumours with extravasal invasion, either with regional lymph node or distant metastasis, that represent a serious clinical challenge. The unveiling of the genomic landscape of these tumours shows that the most frequent mutations occur in tyrosine kinase receptors (RET), in components of the MAPK/PI3K signalling pathway (RAS and BRAF) or chromosomal rearrangements (RET/PTC and NTRK hybrids); thus, tyrosine-kinase inhibitor (TKI) treatments arose in the last decade as the most effective therapeutic option for these aggressive tumours to mitigate the MAPK/PI3K activation. In this review, we summarize the variants of malignant thyroid cancers, the molecular mechanisms and factors known to contribute to thyroid cell plasticity and the approved drugs in the clinical trials and those under investigation, providing an overview of available treatments toward a genome-driven oncology, the only opportunity to beat cancer eventually through tailoring the therapy to individual genetic alterations. However, radiotherapeutic and chemotherapeutic resistances to these anticancer treatments are common and, wherever possible, we discuss these issues.