Novel Inhibitor-Based Therapies for Thyroid Cancer-An Update

GNA15 facilitates the malignant development of thyroid carcinoma cells via the BTK-mediated MAPK signaling pathway

G protein subunit alpha 15 (GNA15) is recognized as an oncogene for some cancers, however, its role in thyroid carcinoma (TC) is elusive and is investigated in this study. Concretely, bioinformatics was employed to analyze the GNA15 expression profile in TC. The effect of GNA15 on TC cell functions was examined using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), colony formation, and Transwell assays. Expressions of extracellular regulated protein kinase (ERK), c-Jun N-terminal kinase (JNK), and p38 were determined using Western blot. The involvement of Bruton tyrosine kinase (BTK) in the mechanism of GNA15 was investigated by BTK knockdown and rescue assay. GNA15 presented an overexpression pattern in TC samples, which facilitated the viability, proliferation, migration, and invasion of TC cells; GNA15 silencing led to converse results. Ratios of p-ERK/ERK, p-JNK/JNK, and p-p38/p38 were upregulated by GNA15 overexpression. The BTK deficiency weakened the aforementioned behaviors of TC cells and blocked the MAPK signaling pathway, however, these effects were counteracted by GNA15 overexpression. Collectively, GNA15 contributes to the malignant development of TC cells by binding to BTK and thus activating the MAPK signaling pathway.

No Correlation between PD-L1 and NIS Expression in Lymph Node Metastatic Papillary Thyroid Carcinoma

Approximately 90% of thyroid cancers are differentiated thyroid cancers (DTCs), originating from follicular epithelial cells. Out of these, 90% are papillary thyroid cancer (PTC), and 10% are follicular thyroid cancer (FTC). The standard care procedure for PTC includes surgery, followed by radioiodine (RAI) ablation and thyroid-stimulating hormone (TSH) suppressive therapy. Globally, treating radioiodine-refractory DTC poses a challenge. During malignant transformation, thyroid epithelial cells often lose their ability to absorb radioiodine due to impaired membrane targeting or lack of NIS (sodium/iodide symporter) expression. Recent reports show an increase in PD-L1 (programmed death ligand 1) expression in thyroid cancer cells during dedifferentiation. However, no research exists wherein NIS and PD-L1 expression are analyzed together in thyroid cancer. Therefore, we aimed to investigate and correlate PD-L1 and NIS expression within primary tumor samples of lymph node metastatic PTC. We analyzed the expression of hNIS (human sodium/iodide symporter) and PD-L1 in primary tumor samples from metastatic PTC patients using immunohistochemistry. Immunohistochemistry analysis of PD-L1 and NIS was conducted in 89 and 86 PTC cases, respectively. Any subcellular NIS localization was counted as a positive result. PD-L1 expression was absent in 25 tumors, while 58 tumors displayed PD-L1 expression in 1-50% of their cells; in 6 tumors, over 50% of the cells tested positive for PD-L1. NIS immunohistochemistry was performed for 86 primary papillary carcinomas, with 51 out of 86 tumors showcasing NIS expression. Only in seven cases was NIS localized in the plasma membrane; in most tumors, NIS was primarily found in the intracytoplasmic membrane compartments. In the case of PD-L1 staining, cells showing linear membrane positivity of any intensity were counted as positive. The evaluation of NIS immunostaining was simpler: cells showing staining of any intensity of cytoplasmic or membranous fashion were counted as positive. The number of NIS positive cells can be further divided into cytoplasmic and membrane positive compartments. There was no observed correlation between PD-L1 and NIS expression. We can speculate that the manipulation of the PD-1/PD-L1 axis using anti-PD-L1 or anti-PD-1 antibodies could reinstate the functional expression of NIS. However, based on our study, the only conclusion that can be drawn is that there is no correlation between the percentage of NIS- or PD-L1-expressing tumor cells in the primary tumor of lymph node metastatic PTC.

Long-term survival outcomes of systemic therapy in patients with isolated and mixed medullary thyroid cancer

Background

Medullary thyroid carcinoma (MTC) is an uncommon thyroid cancer with limited treatment options for advanced disease. A small subset exhibits mixed MTC histology with both medullary and well-differentiated components. We investigated survival outcomes with systemic therapy in isolated versus mixed MTC using a large population-based cohort.

Methods

Patients diagnosed with MTC from 2000 to 2019 were identified in the National Cancer Institute's Surveillance, Epidemiology, and End Results database. The overall and thyroid cancer-specific survivals were compared between isolated (n = 1814) and mixed (n = 113) MTC cohorts. The impact of postoperative systemic therapy on survival was analyzed.

Results

No significant difference in 10-year overall survival was observed between isolated (77.4 %) and mixed (75.2 %) MTC in a cohort of 1927 patients. Median overall survival was similar between isolated (136.9 months) and mixed MTC (129.0 months), p = 0.81. While systemic therapy improved 10-year survival in isolated MTC (83.2 % vs. 76.9 %, p < 0.001), no benefit was seen in mixed MTC (76.4 % vs. 74.2 %, p = 0.82). Multivariate analysis confirmed survival gains with systemic therapy for isolated (HR = 0.763, 95%CI = 0.590-0.987, p = 0.040) but not mixed MTC (HR = 0.909, 95%CI = 0.268-3.079, p = 0.88).

Conclusions

In this large population-based study, no significant survival difference was observed between isolated and mixed MTC. Systemic therapy was associated with improved survival in isolated MTC, but not in the mixed subtype. These findings suggest a differential treatment response that warrants further investigation in prospective studies and may inform histology-tailored management strategies for mixed MTC.

Medullary Thyroid Cancer: Molecular Drivers and Immune Cellular Milieu of the Tumour Microenvironment-Implications for Systemic Treatment

In this review, we explore the underlying molecular biology of medullary thyroid carcinoma (MTC) and its interplay with the host immune system. MTC is consistently driven by a small number of specific pathogenic variants, beyond which few additional genetic events are required for tumorigenesis. This explains the exceedingly low tumour mutational burden seen in most MTC, in contrast to other cancers. However, because of the low tumour mutational burden (TMB), there is a correspondingly low level of tumour-associated neoantigens that are presented to the host immune system. This reduces tumour visibility and vigour of the anti-tumour immune response and suggests the efficacy of immunotherapy in MTC is likely to be poor, acknowledging this inference is largely based on the extrapolation of data from other tumour types. The dominance of specific RET (REarranged during Transfection) pathogenic variants in MTC tumorigenesis rationalizes the observed efficacy of the targeted RET-specific tyrosine kinase inhibitors (TKIs) in comparison to multi-kinase inhibitors (MKIs). Therapeutic durability of pathway inhibitors is an ongoing research focus. It may be limited by the selection pressure TKI treatment creates, promoting survival of resistant tumour cell clones that can escape pathway inhibition through binding-site mutations, activation of alternate pathways, and modulation of the cellular and cytokine milieu of the tumour microenvironment (TME).

Papillary Thyroid Cancer Remodels the Genetic Information Processing Pathways

The genetic causes of the differentiated, highly treatable, and mostly non-fatal papillary thyroid cancer (PTC) are not yet fully understood. The mostly accepted PTC etiology blames the altered sequence or/and expression level of certain biomarker genes. However, tumor heterogeneity and the patient's unique set of favoring factors question the fit-for-all gene biomarkers. Publicly accessible gene expression profiles of the cancer nodule and the surrounding normal tissue from a surgically removed PTC tumor were re-analyzed to determine the cancer-induced alterations of the genomic fabrics responsible for major functional pathways. Tumor data were compared with those of standard papillary and anaplastic thyroid cancer cell lines. We found that PTC regulated numerous genes associated with DNA replication, repair, and transcription. Results further indicated that changes of the gene networking in functional pathways and the homeostatic control of transcript abundances also had major contributions to the PTC phenotype occurrence. The purpose to proliferate and invade the entire gland may explain the substantial transcriptomic differences we detected between the cells of the cancer nodule and those spread in homo-cellular cultures (where they need only to survive). In conclusion, the PTC etiology should include the complex molecular mechanisms involved in the remodeling of the genetic information processing pathways.

Expression of pyroptosis-associated genes and construction of prognostic model for thyroid cancer

Background

Thyroid cancer (THCA) is a common endocrine malignancy. This study aimed to explore the expression of pyroptosis-related genes in THCA and establish a prognosis prediction model.

Methods

Differentially expressed pyroptosis-related genes (DEPRGs) were identified in The Cancer Genome Atlas (TCGA) and the Molecular Signatures Database (MSigDB). Subsequently, these genes were subjected to Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses. A least absolute shrinkage and selection operator (LASSO) regression model was employed to establish a DEPRG signature, and its reliability was validated through survival analysis and receiver operating characteristic (ROC) curves. Patients in TCGA-THCA cohort were stratified into two risk groups. The biological functions of the genes between the two risk groups were assessed through gene set enrichment analysis (GSEA) and gene set variation analysis (GSVA). Finally, expression of DEPRGs was validated using datasets from the Gene Expression Omnibus (GEO) and the Human Protein Atlas (HPA) databases.

Results

Six DEPRGs were identified in TCGA dataset. Through LASSO Cox regression analysis, we determined IL6, TP63, NOD1, and BAX to be significant. Kaplan-Meier survival analysis demonstrated that patients with THCA expressing high levels of NOD1 and classified as low-risk individuals exhibited prolonged survival. The multifactorial ROC curves yielded area under the curve (AUC) scores exceeding 0.7 for risk score, age, and T-stage, affirming their significance as independent prognostic factors as determined by multivariate analysis. Additionally, we observed elevated expression levels of BAX and NOD1 in THCA using data derived from the HPA database and the GEO dataset.

Conclusions

We established a novel DEPRG signature for predicting the prognosis of THCA, potentially offering a promising therapeutic marker for THCA treatment.

Drug-induced inhibition of HMGA and EZH2 activity as a possible therapy for anaplastic thyroid carcinoma

Anaplastic thyroid carcinoma (ATC) is one of the most aggressive and lethal neoplasms in humans, and just limited progresses have been made to extend patient survival and decrease ATC-associated mortality. Thus, the identification of novel therapeutic strategies for treating ATC is needed. Recently, our group has identified two proteins with oncogenic activity, namely HMGA1 and EZH2, with pivotal roles in ATC cancer progression. Therefore, we tested the ability of trabectedin, a HMGA1-targeting drug, and GSK126, an inhibitor of EZH2 enzymatic activity, to impair cell viability of four ATC-derived cell lines. In the present study, we first confirmed the overexpression of HMGA1 and EZH2 in all ATC-derived cell lines and tissues compared to the normal primary thyroid cells and tissues. Then, treatment of the ATC cell lines with trabectedin and GSK126 resulted in a drastic induction of apoptotic cell death, which increased when the ATC cell lines were treated with a combination of both drugs. Conversely, normal primary human thyroid cells did not show any significant reduction in their viability when exposed to the same drugs. Noteworthy, both drugs induced the deregulation of EZH2- and HMGA1-controlled genes. Altogether, these findings propose the combination of trabectedin and GSK126 as possible novel strategy for ATC therapy.

Acute exposure to diesel particulate matter promotes collective cell migration in thyroid cancer cells

Several ecological studies suggest that ambient air pollution is associated with the occurrence of thyroid cancer. In this study, we used certified diesel particulate matter as a proxy for fine particulate matter. Human thyroid cancer cell lines 8505C and TPC-1 were incubated with different concentrations of NIST1650b for 5 days and subjected to functional assays. We found that NIST1650b treatment did not affect short-term cell growth but reduced colony formation at high concentrations. Notably, NIST1650b-treated cells showed altered morphology toward cluster coalescence following treatment. Wound healing assays revealed that leading-edge cells formed protruding tips while maintaining cell-cell adhesion, and a significantly higher ratio of wound closure following treatment at 10 μg/mL was seen in both cell lines. A weak stimulatory effect on transwell cell migration was observed in 8505C cells. Taken together, our results suggest that fine particulate matter induced a coherent phenotype accompanied by augmented collective cell migration in thyroid cancer cells.

The Incidence Trend and Management of Thyroid Cancer-What Has Changed in the Past Years: Own Experience and Literature Review

Because of ambiguous and widely debated observations concerning the incidence, trend, and management of TC, we performed this analysis. We drew attention to some events, such as "cancer screening activity", introduction of noninvasive follicular neoplasm with papillary-like nuclear features (NIFTP) to TC types, possibility of papillary thyroid microcarcinoma (PTMC) active surveillance (AS), occurrence of personalized medicine in TC management, and, finally, COVID-19 pandemic time. Because of the opinion that all changes have been made mostly by PTC, we compared it to the remaining types of TC in terms of incidence, clinical and pathological characteristics, and treatment. We analyzed patients treated in a single surgical center in eastern Europe (Poland). The prevalence of TC significantly increased from 5.15% in 2008 to 13.84% in 2015, and then significantly decreased to 1.33% in 2022 when the COVID-19 pandemic lasted (p < 0.0001). A similar trend was observed for PTC, when the incidence significantly increased to 13.99% in 2015 and then decreased to 1.38% in 2022 (p < 0.0001). At that time, the NIFTP category was introduced, and observation of PTMC began. The prevalence of FTC and MTC also increased until 2015 and then decreased. Significant differences in age, types of surgery, necessity of reoperation, and pTNM between PTCs and other types of TCs were observed. The average age was significantly lower in PTC patients than in patients with the remaining types of TC (p < 0.0001). Four milestones, including NIFTP introduction, the possibility of PTMC AS, personalized cancer medicine, and the COVID-19 pandemic, may have influenced the general statistics of TC.

HLA-G Gene Variability Is Associated with Papillary Thyroid Carcinoma Morbidity and the HLA-G Protein Profile

Human leukocyte antigen (HLA)-G is an immune checkpoint molecule that is highly expressed in papillary thyroid carcinoma (PTC). The HLA-G gene presents several functional polymorphisms distributed across the coding and regulatory regions (5'URR: 5' upstream regulatory region and 3'UTR: 3' untranslated region) and some of them may impact HLA-G expression and human malignancy. To understand the contribution of the HLA-G genetic background in PTC, we studied the HLA-G gene variability in PTC patients in association with tumor morbidity, HLA-G tissue expression, and plasma soluble (sHLA-G) levels. We evaluated 185 PTC patients and 154 healthy controls. Polymorphic sites defining coding, regulatory and extended haplotypes were characterized by sequencing analyses. HLA-G tissue expression and plasma soluble HLA-G levels were evaluated by immunohistochemistry and ELISA, respectively. Compared to the controls, the G0104a(5'URR)G*01:04:04(coding)UTR-03(3'UTR) extended haplotype was underrepresented in the PTC patients, while G0104a(5'URR)G*01:04:01(coding)UTR-03(3'UTR) was less frequent in patients with metastatic and multifocal tumors. Decreased HLA-G tissue expression and undetectable plasma sHLA-G were associated with the G010102a(5'URR)G*01:01:02:01(coding)UTR-02(3'UTR) extended haplotype. We concluded that the HLA-G variability was associated with PTC development and morbidity, as well as the magnitude of the encoded protein expression at local and systemic levels.

Cancer gene analysis of liquid-based cytology specimens using next-generation sequencing: A technical report of bimodal DNA- and RNA-based panel application

BACKGROUND

As liquid-based cytology (LBC) specimens harbor high-quality DNA, genomic analysis using LBC specimens is beneficial for integrative diagnosis. This study aimed to clarify the feasibility of LBC specimens for a bimodal application of DNA- and RNA-based next-generation sequencing (NGS) panels.

METHODS

LBC specimens were prepared from cultured human cancer HEC59 cells using commercially available fixatives (Cellprep, CytoRich Red, and SurePath solutions), and were subjected to NGS for a feasibility study. Clinical LBC specimens of thyroid and salivary gland tumors were prepared using CytoRich Red solution. After DNA and RNA extraction, NGS analyses were performed in a single run using combined DNA- and RNA-based custom-made cancer panels for the detection of gene mutations and fusions.

RESULTS

High-quality DNA and RNA were obtained, and the expected gene mutations and fusions were detected in HEC59 cells using all types of LBC fixatives. Most available clinical cases (18 out of 20) exhibited pathogenic gene mutations (15 cases) and fusion genes (3 cases) using the bimodal DNA- and RNA-based panels. Overall, 18 cases (90%) showed oncogenic mutations or fusion genes of diagnostic values.

CONCLUSION

Simultaneous application of bimodal DNA- and RNA-based gene panels was useful in NGS analysis using residual LBC specimens for integrative diagnosis. Residual LBC specimens for genomic analysis, including fusion gene analysis, are particularly useful for obtaining genomic information before surgical resection.

Cancer Predisposition Syndromes and Thyroid Cancer: Keys for a Short Two-Way Street

Cancer predisposition syndromes are entities determined especially by germinal pathogenic variants, with most of them autosomal dominantly inherited. The risk of a form of cancer is variable throughout life and affects various organs, including the thyroid. Knowing the heterogeneous clinical picture and the existing genotype-phenotype correlations in some forms of thyroid cancer associated with these syndromes is important for adequate and early management of patients and families. This review synthesizes the current knowledge on genes and proteins involved in cancer predisposition syndromes with thyroid cancer and the phenomena of heterogeneity (locus, allelic, mutational, and clinical).

Resolving the role of podoplanin in the motility of papillary thyroid carcinoma-derived cells using RNA sequencing

The intracellular level of podoplanin (PDPN), a transmembrane protein of still unclear function, is frequently altered in metastatic tumors. High expression of PDPN is frequently observed in papillary thyroid cancer (PTC) specimens. Similarly, PTC-derived cell lines (BCPAP and TPC1, harboring the BRAF V600E mutation and RET/PTC1 fusion, respectively), also present enhanced PDPN yield. We previously reported that depletion of PDPN impairs migration of TPC1 cells, but augments metastasis of BCPAP cells. Interestingly, this phenomenon stays in contrast to the migratory pattern observed for wild-type cells, where TPC1 exhibited higher motility than BCPAP cells. Here, we aimed to elucidate the potential role of PDPN in regulation of molecular mechanisms leading to the diverse metastatic features of the studied PTC-derived cells. We consider that this phenomenon may be caused by alternative regulation of signaling pathways due to the presence of the mutated BRAF allele or RET/PTC1 fusion. The high-throughput RNA sequencing (RNA-seq) technique was used to uncover the genes and signaling pathways affected in wild-type and PDPN-depleted TPC1 and BCPAP cells. We found that changes in the expression of various factors of signaling pathways, like RHOA and RAC1 GTPases and their regulators, are linked with both high PDPN levels and presence of the BRAF V600E mutation. We imply that the suppressed motility of wild-type BCPAP cells results from overactivation of RHOA through natively high PDPN expression. This process is accompanied by inhibition of the PI3K kinase and consequently RAC1, due to overactivation of RAS-mediated signaling and the PTEN regulator.

The Difference in Clinical Behavior of Gene Fusions Involving RET/PTC Fusions and THADA/IGF2BP3 Fusions in Thyroid Nodules

BACKGROUND

Molecular testing has been used as an adjunct to morphological evaluation in the workup of thyroid nodules. This study investigated the impact of two gene fusions, RET/PTC and THADA/IGF2BP3, that have been described as oncogenic events in thyroid neoplasms.

METHODS

We performed a retrospective, single-centered study at a McGill University teaching hospital in Montreal, Canada, from January 2016 to August 2021. We included patients who underwent surgery for thyroid nodules that pre-operatively underwent molecular testing showing either RET/PTC or THADA/IGF2BP3 gene fusion.

RESULTS

This study included 697 consecutive operated thyroid nodules assessed using molecular testing, of which five had the RET/PTC fusion and seven had the THADA/IGF2BP3 fusion. Of the five nodules in the RET/PTC group, 100% were malignant and presented as Bethesda V/VI. Eighty percent (4/5) were found to have lymph node metastasis. Twenty percent (1/5) had extrathyroidal extensions. Sixty percent (3/5) were a diffuse sclerosing variant of papillary thyroid carcinoma, and the rest were the classical variant. Of the seven THADA/IGF2BP3 nodules, all presented as Bethesda III/IV and 71.4% (5/7) were malignant based on the final pathology analysis, and 28.6% (2/7) were NIFTP. All the THADA/IGF2BP3 fusion malignancies were a follicular variant of papillary thyroid carcinoma. None had lymph node metastasis or displayed extrathyroidal extensions.

CONCLUSIONS

RET/PTC nodules presented as Bethesda V/VI and potentially had more aggressive features, whereas THADA/IGF2BP3 nodules presented as Bethesda III/IV and had more indolent behavior. This understanding may allow clinicians to develop more targeted treatment plans, such as the extent of surgery and adjuvant radioactive iodine treatment.

Expression of pY397-FAK and Its miR Regulators Drive Dedifferentiation in the Thyroid Neoplasia Spectrum

Thyroid carcinomas are growing malignancies worldwide. They encompass several diagnostic categories with varying degrees of dedifferentiation. Focal adhesion kinase is involved in cellular communication and locomotion. It is regulated on a posttranscriptional level by miR-7, miR-135a, and miR-138 and on a posttranslational level by autophosphorylation at Y397 (pY397-FAK). We related regulators of FAK with histologic dedifferentiation, clinicopathological factors, and differential diagnosis in the thyroid neoplasia spectrum. We classified 82 cases into 5 groups with increasing aggressiveness: healthy tissue, follicular and classical variants of papillary thyroid carcinoma (PTC), dedifferentiated PTC, and anaplastic carcinoma. MiRs were analyzed by RT-qPCR. Protein expression of pY397-FAK was analyzed by immunohistochemistry (separately in the membrane, cytoplasm, and nuclear compartment) and Western blot. All three miRs were upregulated in healthy tissue compared to malignant, while pY397-FAK was downregulated. MiRs and pY397-FAK were not mutually correlated. MiR-135a-5p was decreasing while membranous and cytoplasmic pY397-FAK increased with dedifferentiation. Neither miR correlated with clinicopathological factors. MiR-135a-5p, miR-138-5p, and membranous and cytoplasmic pY397-FAK discriminated the follicular from the classical variant of PTC. Disturbances of FAK regulation on different levels contribute to neoplastic dedifferentiation. pY397-FAK exerts its oncogenic role in the membrane and cytoplasm. Diagnostically, miRs-135a-5p, miR-138-5p, and membranous and cytoplasmic pY397-FAK differentiated between classical and follicular PTC.

Acetate-Mediated Odorant Receptor OR51E2 Activation Results in Calcitonin Secretion in Parafollicular C-Cells: A Novel Diagnostic Target of Human Medullary Thyroid Cancer

Medullary thyroid cancer originates from parafollicular C-cells in the thyroid. Despite successful thyroidectomy, localizing remnant cancer cells in patients with elevated calcitonin and carcinoembryonic antigen levels remains a challenge. Extranasal odorant receptors are expressed in cells from non-olfactory tissues, including C-cells. This study evaluates the odorant receptor signals from parafollicular C-cells, specifically, the presence of olfactory marker protein, and further assesses the ability of the protein in localizing and treating medullary thyroid cancer. We used immunohistochemistry, immunofluorescent staining, Western blot, RNA sequencing, and real time-PCR to analyze the expression of odorant receptors in mice thyroids, thyroid cancer cell lines, and patient specimens. We used in vivo assays to analyze acetate binding, calcitonin secretion, and cAMP pathway. We also used positron emission tomography (PET) to assess C11-acetate uptake in medullary thyroid cancer patients. We investigated olfactory marker protein expression in C-cells in patients and found that it co-localizes with calcitonin in C-cells from both normal and cancer cell lines. Specifically, we found that OR51E2 and OR51E1 were expressed in thyroid cancer cell lines and human medullary thyroid cancer cells. Furthermore, we found that in the C-cells, the binding of acetate to OR51E2 activates its migration into the nucleus, subsequently resulting in calcitonin secretion via the cAMP pathway. Finally, we found that C11-acetate, a positron emission tomography radiotracer analog for acetate, binds competitively to OR51E2. We confirmed C11-acetate uptake in cancer cells and in human patients using PET. We demonstrated that acetate binds to OR51E2 in C-cells. Using C11-acetate PET, we identified recurrence sites in post-operative medullary thyroid cancer patients. Therefore, OR51E2 may be a novel diagnostic and therapeutic target for medullary thyroid cancer.

Clinicopathological and Genetic Characteristics of Patients of Different Ages with Diffuse Sclerosing Variant Papillary Thyroid Carcinoma

Diffuse sclerosing variant papillary thyroid carcinoma (DSVPTC) is commonly observed in young patients, with a median age at diagnosis in the third decade of life. Further, the risk of recurrence is higher for DSVPTC than for classical PTC. Therefore, this study aimed to describe the clinicopathological and genetic characteristics of patients of different ages with DSVPTC. We retrospectively reviewed 397 patients who underwent thyroidectomy for DSVPTC at Gangnam Severance Hospital, Yonsei University, from January 2005 to December 2017. The mean age at diagnosis was 36.7 ± 11.6 years, with most patients (163, 41.1%) aged 31-40 years. DSVPTC was predominant in women (276, 69.5%). We observed recurrence in 46 (11.6%) patients, with regional nodal recurrence being the most common type of recurrence (32 patients, 69.6%). The mean tumour size was larger in younger patients than in older patients. DSVPTC was more aggressive in paediatric patients with a larger-sized tumour, more common multiplicity, and lateral neck metastasis. Through random sampling, we selected 41 patients by age group and examined the mutations in 119 genes using next-generation sequencing. BRAF, KRAS, and TERT displayed relatively higher mutation rates than other genes. DSVPTC displays different clinical, pathological, and molecular profiles than classical PTC. The BRAF, KRAS, and TERT mutations are the most important, with age-specific differences.

Cyanidin as potential anticancer agent targeting various proliferative pathways

A natural compound cyanidin, which is a type of anthocyanin present in pigmented leaves, fruits, and flowers; distributed widely in berries, apples, and oranges possess anticancer activities, thus curing various types of cancer such as breast, liver, lung, prostate, and thyroid cancer. The article provides an insight into the potential of using a single phytochemical, cyanidin to treat various cancer types including breast, liver, lung, prostate, and thyroid cancer. Information about cyanidin and its pharmacological impact on cancer was collected from books, scientific journals, and reports through electronic data search (Web of Science, Scifinder, PubMed, Scopus, Google Scholar, Elsevier, Springer, Wiley, ACS, Science Direct, CNKI as well as Kew Plants of the Word Online) and library. Cyanidin produces its effects against cancer probably by inhibiting (RAS, MAPK) and activating (caspases-3 and P-38) innovative molecular pathways. It may cause cell cycle arrest, cell differentiation processes and changes in redox status which trigger the cytotoxic chemotherapeutic effects. However, it also optimizes the chemotherapeutic targets which are cancer cells less responsive to chemotherapy. Cancer is considered the most widely spread disease and cyanidin from natural origin provides an essential role in treatment of cancer by approaching various mechanistic pathways.

Cabozantinib, Vandetanib, Pralsetinib and Selpercatinib as Treatment for Progressed Medullary Thyroid Cancer with a Main Focus on Hypertension as Adverse Effect

This manuscript investigates cabozantinib, vandetanib, pralsetinib, and selpercatinib, four tyrosine kinase inhibitors (TKIs), which are used to treat advanced and/or metastatic medullary thyroid cancer (MTC). Data on efficacy and safety are presented with the main focus on treatment-related hypertension, a well-known adverse effect (AE) of these TKIs. Taken together, TKI-induced hypertension is rarely a dose-limiting side effect. However, with increasing survival times of patients under treatment, hypertension-associated complications can be expected to be on the rise without proper medication.

Molecular features of aggressive thyroid cancer

Poorly differentiated thyroid cancer (PDTC) and anaplastic thyroid cancer (ATC) have a worse prognosis with respect to well differentiated TC, and the loss of the capability of up-taking ¹³¹I is one of the main features characterizing aggressive TC. The knowledge of the genomic landscape of TC can help clinicians to discover the responsible alterations underlying more advance diseases and to address more tailored therapy. In fact, to date, the antiangiogenic multi-targeted kinase inhibitor (aaMKIs) sorafenib, lenvatinib, and cabozantinib, have been approved for the therapy of aggressive radioiodine (RAI)-resistant papillary TC (PTC) or follicular TC (FTC). Several other compounds, including immunotherapies, have been introduced and, in part, approved for the treatment of TC harboring specific mutations. For example, selpercatinib and pralsetinib inhibit mutant RET in medullary thyroid cancer but they can also block the RET fusion proteins-mediated signaling found in PTC. Entrectinib and larotrectinib, can be used in patients with progressive RAI-resistant TC harboring TRK fusion proteins. In addition FDA authorized the association of dabrafenib (BRAF^V600E inhibitor) and trametinib (MEK inhibitor) for the treatment of BRAF^V600E-mutated ATC. These drugs not only can limit the cancer spread, but in some circumstance they are able to induce the re-differentiation of aggressive tumors, which can be again submitted to new attempts of RAI therapy. In this review we explore the current knowledge on the genetic landscape of TC and its implication on the development of new precise therapeutic strategies.

Identification of Circulating Exosomal microRNAs Associated with Radioiodine Refractory in Papillary Thyroid Carcinoma

Papillary thyroid carcinoma (PTC) has a favorable prognosis, but a fraction of cases show progressive behaviors, becoming radioiodine refractory (RAIR) PTC. To explore circulating exosomal microRNAs (miRNAs) associated with RAIR PTC, the miRNA profiles in exosomes from parental and induced RAIR cell lines were firstly identified with a next-generation sequencing technique. The Na⁺/I^- symporter (NIS) related miRNAs were then validated by quantitative real-time PCR (qRT-PCR) in plasma of PTC patients with non-¹³¹I-avid metastases and those with ¹³¹I-avid metastases. The regulation of exosomal miRNAs on NIS were also verified. We identified that miR-1296-5p, upregulation in exosomes from RAIR cell lines, and the plasma of patients with RAIR PTC achieved the largest areas under the curve (AUC) of 0.911 and that it is an independent risk factor for RAIR PTC. In addition, miR-1296-5p was abundantly detected in the tissue of RAIR PTC and can directly target downstream gene of NIS. Taken together, our findings suggested that circulating exosomal miRNAs, particularly miR-1296-5p, may be involved in the pathogenesis of RAIR PTC by directly targeting NIS.

Rationale Efficacy and Safety Evidence of Lenvatinib and Pembrolizumab Association in Anaplastic Thyroid Carcinoma

Anaplastic thyroid carcinoma (ATC) are highly aggressive malignant tumors with poor overall prognosis despite multimodal therapy. As ATC are extremely rare, no randomized controlled study has been published for metastatic disease. Thyrosine kinase inhibitors, especially lenvatinib and immune checkpoint inhibitors such as pembrolizumab, are emerging drugs for ATC. Few studies have reported the efficacity of pembrolizumab and lenvatinib association, resulting in its frequent off-label use. In this review, we discuss rationale efficacy and safety evidence for the association of lenvatinib and pembrolizumab in ATC. First, we discuss preclinical rationale for pembrolizumab monotherapy, lenvatinib monotherapy and synergistic action of pembrolizumab and lenvatinib in the metastatic setting. We also discuss clinical evidence for immunotherapy and pembrolizumab in ATC through the analysis of studies evaluating immunotherapy, lenvatinib and pembrolizumab lenvatinib association in ATC. In addition, we discuss the safety of this association and potential predictive biomarkers of efficiency.

Towards an era of precise diagnosis and treatment: Role of novel molecular modification-based imaging and therapy for dedifferentiated thyroid cancer

Dedifferentiated thyroid cancer is the major cause of mortality in thyroid cancer and is difficult to treat. Hence, the essential molecular mechanisms involved in dedifferentiation should be thoroughly investigated. Several studies have explored the biomolecular modifications of dedifferentiated thyroid cancer such as DNA methylation, protein phosphorylation, acetylation, ubiquitination, and glycosylation and the new targets for radiological imaging and therapy in recent years. Novel radionuclide tracers and drugs have shown attractive potential in the early diagnosis and treatment of dedifferentiated thyroid cancer. We summarized the updated molecular mechanisms of dedifferentiation combined with early detection by molecular modification-based imaging to provide more accurate diagnosis and novel therapeutics in the management of dedifferentiated thyroid cancer.

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.

Epidermal growth factor receptor activation confers resistance to lenvatinib in thyroid cancer cells

Thyroid cancer is the most common endocrine malignancy. A multitargeted tyrosine kinase inhibitor, lenvatinib, has been used for the treatment of advanced thyroid cancer. To elucidate the mechanism of resistance to lenvatinib in thyroid cancer cells, we established lenvatinib‐resistant sublines and analyzed the molecular mechanisms of resistance. Two thyroid cancer cell lines (TPC‐1 and FRO) were used, and resistant sublines for lenvatinib (TPC‐1/LR, FRO/LR) were established. In TPC‐1/LR, the phosphorylation of epidermal growth factor receptor (EGFR), extracellular signal‐regulated kinase (ERK), and Akt was enhanced whereas in FRO/LR, the phosphorylation of EGFR and downstream signal transduction molecules was not enhanced. The addition of epidermal growth factor decreased sensitivity to lenvatinib in TPC‐1 and FRO. The combination of EGFR inhibitors lapatinib and lenvatinib significantly inhibited the growth of TPC‐1/LR in both in vitro and mouse xenograft models. Short‐term exposure to lenvatinib enhanced the phosphorylation of EGFR in six thyroid cancer cell lines regardless of their histological origin or driver gene mutations; however, phosphorylation of ERK was enhanced in all cells except TPC‐1. A synergistic growth‐inhibitory effect was observed in three thyroid cancer cell lines, including intrinsically lenvatinib‐resistant cells. The results indicate that signal transduction via the EGFR pathway may be involved in the development of lenvatinib resistance in thyroid cancer cells. The inhibition of the EGFR pathway simultaneously by an EGFR inhibitor may have therapeutic potential for overcoming lenvatinib resistance in thyroid cancer.

Predictive Biomarkers in Thyroid Cancer

In molecular pathology, predictive biomarkers identify which patients are likely to respond to targeted drugs. These therapeutic agents block specific molecules directly involved in cancer growth, dedifferentiation and progression. Until few years ago, the only targeted drugs available for advanced thyroid cancer included multi-tyrosine kinase inhibitors, mainly targeting the MAPK pathway and the angiogenic signaling. The administration of these drugs does not necessarily require a molecular characterization of tumors to assess the presence of predictive alterations. However, the availability of new selective targeted drugs for thyroid cancer patients is changing the diagnostic strategies for the molecular characterization of these tumors. The search for targetable alterations can be performed directly on tumor tissue by using a variety of methodologies, depending also on the number and type of alterations to test (i.e. single nucleotide variation or gene rearrangement). Herein, a comprehensive review of the currently available targeted treatments for thyroid cancer, related predictive markers and testing methodologies is provided.

Analysis of the Rehabilitation Efficacy and Nutritional Status of Patients After Endoscopic Radical Thyroidectomy by Fast Track Surgery Based on Nutritional Support

Objective

To investigate and analyze the effect of fast track surgery (FTS) based on nutritional support on the improvement of rehabilitation efficacy and nutritional status of patients after radical lumpectomy for thyroid cancer.

Methods

Eighty-six patients admitted to our hospital for radical lumpectomy for thyroid cancer between April 2018 and April 2021 were selected, of which 40 patients admitted between April 2018 and April 2019 were included in the control group with conventional perioperative care. Forty-six patients admitted between May 2019 and April 2021 were included in the trial group with FTS care based on nutritional support. The two groups of patients were compared in terms of postoperative feeding time, length of stay, time out of bed, VAS scores, albumin (ALB), total protein (TP) and prealbumin (PA) levels, negative emotions [Mental Health Test Questionnaire (DCL-90)], quality of life [General Quality of Life Inventory (GQOLI-74)] and complication rates.

Results

The patients in the trial group had shorter feeding time, hospitalization time and time out of bed than the control group (P < 0.05). After the intervention, ALB, TP and PA levels were higher in the trial group than in the control group vs. preoperatively (P < 0.05); VAS scores in the trial group were lower than VAS scores in the control group during the same period (P < 0.05). The postoperative DCL-90 scores of the trial group were lower than those of the control group (P < 0.05); the GQOLI-74 scores and total scores of the trial group were higher than those of the control group at the 3-month postoperative follow-up (P < 0.05). The overall incidence of complications such as hoarseness, choking on water, hand and foot numbness, wound infection, and hypocalemia was lower in the trial group than in the control group (P < 0.05).

Conclusion

The implementation of FTS care based on nutritional support for patients after endoscopic radical thyroidectomyr can effectively improve the postoperative recovery and reduce their pain level, as well as help improve their nutritional status, negative emotions and improve their quality of life, which is worth promoting.

Targeting GLI1 Transcription Factor for Restoring Iodine Avidity with Redifferentiation in Radioactive-Iodine Refractory Thyroid Cancers

Simple Summary

Thyroid cancers have an excellent prognosis by standard therapy of surgery followed by radioactive-iodine therapy. However, metastatic thyroid cancers do not response to radioactive-iodine therapy by losing iodine avidity. Therefore, reversing iodine avidity to metastatic thyroid cancers gives a new chance of applying radioactive-iodine therapy to the cancers. In the current study, we found that GLI1 knockdown can revert iodine non-avid thyroid cancers to iodine avid cancers by increasing expression of thyroid-specific proteins. Restoration of iodine avidity in thyroid cancers makes the cancers sensitive to radioactive-iodine therapy again. Therefore, the GLI1 can be a potential therapeutic target of radioactive-iodine resistant thyroid cancers.

Abstract

Radioactive-iodine (RAI) therapy is the mainstay for patients with recurrent and metastatic thyroid cancer. However, many patients exhibit dedifferentiation characteristics along with lack of sodium iodide symporter (NIS) functionality, low expression of thyroid-specific proteins, and poor RAI uptake, leading to poor prognosis. Previous studies have demonstrated the effect of GLI family zinc finger 1 (GLI1) inhibition on tumor growth and apoptosis. In this study, we investigated the role of GLI1 in the context of redifferentiation and improvement in the efficacy of RAI therapy for thyroid cancer. We evaluated GLI1 expression in several thyroid cancer cell lines and selected TPC-1 and SW1736 cell lines showing the high expression of GLI. We performed GLI1 knockdown and evaluated the changes of thyroid-specific proteins expression, RAI uptake and I-131-mediated cytotoxicity. The effect of GANT61 (GLI1 inhibitor) on endogenous NIS expression was also assessed. Endogenous NIS expression upregulated by inhibiting GLI1, in addition, increased expression level in plasma membrane. Also, GLI1 knockdown increased expression of thyroid-specific proteins. Restoration of thyroid-specific proteins increased RAI uptake and I-131-mediated cytotoxic effect. Treatment with GANT61 also increased expression of endogenous NIS. Targeting GLI1 can be a potential strategy with redifferentiation for restoring RAI avidity in dedifferentiated thyroid cancers.

State of the Art in the Current Management and Future Directions of Targeted Therapy for Differentiated Thyroid Cancer

Two-thirds of differentiated thyroid cancer (DTC) patients with distant metastases would be classified as radioactive iodine-refractory (RAIR-DTC), evolving into a poor outcome. Recent advances underlying DTC molecular mechanisms have shifted the therapy focus from the standard approach to targeting specific genetic dysregulations. Lenvatinib and sorafenib are first-line, multitargeted tyrosine kinase inhibitors (TKIs) approved to treat advanced, progressive RAIR-DTC. However, other anti-angiogenic drugs, including single targeted TKIs, are currently being evaluated as alternative or salvage therapy after the failure of first-line TKIs. Combinatorial therapy of mitogen-activated protein kinase (MAPK) and phosphoinositide 3-kinase (PI3K) signalling cascade inhibitors has become a highly advocated strategy to improve the low efficiency of the single agent treatment. Recent studies pointed out targetable alternative pathways to overcome the resistance to MAPK and PI3K pathways’ inhibitors. Because radioiodine resistance originates in DTC loss of differentiation, redifferentiation therapies are currently being explored for efficacy. The present review will summarize the conventional management of DTC, the first-line and alternative TKIs in RAIR-DTC, and the approaches that seek to overcome the resistance to MAPK and PI3K pathways’ inhibitors. We also aim to emphasize the latest achievements in the research of redifferentiation therapy, immunotherapy, and agents targeting gene rearrangements in advanced DTC.

GLUT1 and ASCT2 Protein Expression in Papillary Thyroid Carcinoma Patients and Relation to Hepatitis C Virus: A Propensity-Score Matched Analysis

Purpose

Recently, glucose and amino acid transporters have gradually become a hot topic in thyroid gland biology and cancer research. We aimed to investigate the expressions of glucose transporter 1 (GLUT1) and glutamine transporter 2 (ASCT2) in papillary thyroid carcinoma (PTC) and their clinical significance and relation to HCV-related hepatitis.

Patients and Methods

Screening 202 TC tissue samples against the selection criteria using a propensity-score matched analysis to adjust for age, sex, side of tumor, histopathological variants, TNM staging system, and the positivity for HCV yielded 51 matched (17 HCV positive and 34 HCV negative) PTC samples. The expressions of GLUT1 and ASCT2 expressions were detected by immunohistochemical staining. Kaplan–Meier survival curves were generated for disease-free and overall survival, and multivariate Cox regression analysis was applied to identify predictors for mortality.

Results

Of 51 thyroid cancer tissues, 85% showed positive GLUT1 cytoplasmic staining, and 26% had a high expression score. All thyroid cancer specimens demonstrated ASCT2 cytoplasmic staining with membranous accentuation. Of these, 78% showed a high expression score, and 22% showed weak staining. On stratifying the study cohort based on the HCV status, HCV negative cohort showed a significantly higher immunoreactivity score for GLUT1 (p = 0.004) but not ASCT2 (p = 0.94) than HCV positive group. The expressions of the studied transporters showed no significant associations with the prognostic features of PTC nor the disease-free/overall survival.

Conclusion

GLUT1 and ASCT2 immunohistochemical staining showed positive expression with variable intensity in nearly 85% and 100% of PTC tissue samples compared to normal ones, respectively. Furthermore, GLUT1 protein expression, not ASCT2, showed a higher immunoreactivity score in PTC patients who are negative for HCV than cancer patients with positive HCV. Meanwhile, the expression of both protein markers was not associated with the clinicopathological characteristics of the studied PTC patients. Further large-scale multicenter studies are recommended to validate the present findings.

Advances in pharmacotherapy for advanced thyroid cancer of follicular origin (PTC, FTC). New approved drugs and future therapies

INTRODUCTION

The most common altered signaling found in aggressive iodine-refractory Thyroid cancer derived from follicular cells (RAI-TC) are RTK, MAPK, PI3K, WNT, BRAF, RAS, RET, and TP53. Tyrosine Kinase Inhibitors (TKI) are multi-kinase inhibitors able to act against different pathways, that elicit an anti-neoplastic activity.

AREAS COVERED

The aim of this paper is to review recent novel molecular therapies of RAI-TC. Recently, sorafenib and lenvatinib, have been approved for the treatment of aggressive RAI-TC. Other studies are evaluating vandetanib and selumetinib in RAI-TC. Furthermore, preliminary studies have evaluated dabrafenib, and vemurafenib in BRAF mutated RAI-TC patients to re-induce 131-iodine uptake. The interplay between cells of the immune system and cancer cells can be altered by immune checkpoints inhibitors. The expression of PDL1 in RAI-TC was related to tumor recurrence and poor survival. Several clinical trials are investigating a combination of different therapies, such as lenvatinib and pembrolizumab.

EXPERT OPINION

Mechanisms of resistance to TKIs inhibitors can be of intrinsic or acquired origin. An acquired resistance to lenvatinib, or sorafenib can be due to upregulation of FGFR; therefore anti-FGFR agents are evaluated. A new strategy is to combine TKIs with immunotherapy. Several studies are evaluating lenvatinib and pembrolizumab in RAI-TC patients.