Expression profiles of pivotal microRNAs and targets in thyroid papillary carcinoma: an analysis of The Cancer Genome Atlas

Circular RNA eukaryotic translation initiation factor 6 facilitates TPC-1 cell proliferation and invasion through the microRNA-138-5p/lipase H axis

Both circular RNA eukaryotic translation initiation factor 6 (circEIF6) and microRNA (miR)-138-5p participate in thyroid cancer (TC) progression. Nevertheless, the relationship between them remains under-explored. Hence, this research ascertained the mechanism of circEIF6 in TC via miR-138-5p. After TC tissues and cells were harvested, circEIF6, miR-138-5p, and lipase H (LIPH) levels were assessed. The binding relationships among circEIF6, miR-138-5p, and LIPH were analyzed. The impacts of circEIF6, miR-138-5p, and LIPH on the invasive and proliferative abilities of TPC-1 cells were examined by Transwell and EdU assays. Tumor xenograft in nude mice was established for in vivo validation of the impact of circEIF6. CircEIF6 expression was high in TC cells and tissues. Additionally, miR-138-5p was poor and LIPH level was high in TC tissues. Mechanistically, circEIF6 competitively bound to miR-138-5p to elevate LIPH via a competitive endogenous RNA mechanism. Silencing of circEIF6 reduced TPC-1 cell proliferative and invasive properties, which was annulled by further inhibiting miR-138-5p or overexpressing LIPH. Likewise, circEIF6 silencing repressed the growth of transplanted tumors, augmented miR-138-5p expression, and diminished LIPH expression in nude mice. Conclusively, circEIF6 silencing reduced LIPH level by competitive binding to miR-138-5p, thus subduing the proliferation and invasion of TPC-1 cells.

MiR-20b Tissue Expression Level Displays the Diagnostic Value in Papillary Thyroid Carcinoma

Background

Detection of cancer in patients with thyroid nodules requires sensitive and specific diagnostic modalities that are accurate and inexpensive. This study aimed to identify a potential microRNA(miRNA) panel to detect papillary thyroid carcinoma (PTC).

Methods

Following a comprehensive literature review as well as miRNA target predictor databases, Real-time PCR was used to quantify the expression of candidate miRNAs in 59 tissue specimens from 30 patients with PTC and 29 patients with benign nodules. A receiver operating characteristic (ROC) curve analysis was used to assess the accuracy of miRNA expression levels compared to the pathology report as the gold standard. Based on prediction results, four miRNAs, including miR-9, miR-20b, miR-221, and miR-222, were selected to evaluate their expression level in Iranian thyroid samples.

Results

A significant difference between the tissue expression level of miR-20b, miR-9, miR-222, and miR-221 was detected in the PTC group compared with non-PTC (P < 0.05). The area under the curves for the included miRs were 1, 0.98, 0.99, 0.98, and 1, respectively.

Conclusion

Our results confirmed deregulations of miR-20b as well as miR-222, miR-221, and miR-9 in PTC and, therefore, could be used as a helpful miRNA panel to differentiate PTC from benign nodules, which results in the more efficient clinical management of PTC patients.

Thyroid Cancer Persistence in Patients with Unreliable Thyroglobulin Measurement: Circulating microRNA as Candidate Alternative Biomarkers

BACKGROUND

We aimed to evaluate the role of circulating miRNAs as a biomarker of the persistence of papillary thyroid cancer (PTC) in patients with an "uninformative" thyroglobulin (Tg) measurement.

METHODS

We prospectively enrolled 49 consecutive PTC patients with Tg-positive antibodies (TgAb) who had undergone a (near)-total thyroidectomy and ¹³¹I therapy (RIT). The serum thyroid stimulating hormone (TSH), Tg, and TgAb levels were measured before and at 6 and 12 months after RIT, respectively. The serum miRNA (221, 222, 375, 155, and 146b) levels were measured simultaneously.

RESULTS

The response to the initial therapy was assessed according to the 2015 ATA criteria. A decrease in 50% or more of serum miRNA over time was observed in 41/49 PTC patients, who showed an excellent response (ER), but six and two patients were classified to have an indeterminate/incomplete biochemical or incomplete structural response to initial therapy.

CONCLUSION

Serum miRNA kinetics emerge as a promising biomarker for the early detection of a persistent disease in PTC patients with uninformative Tg results.

MicroRNAs in Papillary Thyroid Cancer: What Is New in Diagnosis and Treatment

Introduction

Papillary thyroid cancer (PTC) accounts for up to 80% of thyroid malignancies. New diagnostic and therapeutic options are suggested including innovative molecular methods. MicroRNAs (miRNAs) are nonprotein coding single-stranded RNAs that regulate many cell processes. The aim of the present study is to review the deregulated miRNAs associated with PTCs.

Methods

A bibliographic research was conducted, resulting in 272 articles referred to miRNAs and PTC. Regarding our exclusion criteria, 183 articles were finally included in our review.

Results

A remarkably large number of miRNAs have been found to be deregulated during PTC manifestation in the literature. The deregulated miRNAs are detected in tissue samples, serum/plasma, and FNA samples of patients with PTC. These miRNAs are related to several molecular pathways, involving genes and proteins responsible for important biological processes. MiRNA deregulation is associated with tumor aggressiveness, including larger tumor size, multifocality, extrathyroidal extension, lymphovascular invasion, lymph node and distant metastasis, and advanced tumor node metastasis stage.

Conclusion

MiRNAs are proposed as new diagnostic and therapeutic tools regarding PTC. They could be essential biomarkers for PTC diagnosis applied in serum and FNA samples, while their contribution to prognosis is of great importance.

Changes in Exosomal miRNA Composition in Thyroid Cancer Cells after Prolonged Exposure to Real Microgravity in Space

As much as space travel and exploration have been a goal since humankind looked up to the stars, the challenges coming with it are manifold and difficult to overcome. Therefore, researching the changes the human organism undergoes following exposure to weightlessness, on a cellular or a physiological level, is imperative to reach the goal of exploring space and new planets. Building on the results of our CellBox-1 experiment, where thyroid cancer cells were flown to the International Space Station, we are now taking advantage of the newest technological opportunities to gain more insight into the changes in cell–cell communication of these cells. Analyzing the exosomal microRNA composition after several days of microgravity might elucidate some of the proteomic changes we have reported earlier. An array scan of a total of 754 miRNA targets revealed more than 100 differentially expressed miRNAs in our samples, many of which have been implicated in thyroid disease in other studies.

CircRNA NRIP1 promotes papillary thyroid carcinoma progression by sponging mir-195-5p and modulating the P38 MAPK and JAK/STAT pathways

BACKGROUND

Circular RNAs (circRNAs) have become a hot topic in the area of tumor biology due to its closed structure and the post-transcriptional regulatory effect. This study aims to clarify the roles of circRNA nuclear receptor-interacting protein 1 (NRIP1; circNRIP1) and the possible mechanisms in papillary thyroid carcinoma (PTC).

METHODS

The real-time PCR was used to detect the expression level of CircRNA NRIP1 in PTC specimens and cell lines. The effects of CircRNA NRIP1 and miR-195-5p on the PTC cell functions were detected by MTT, transwell, and flow cytometry assays. Dual-luciferase reporter assays and pull down assays were used to verify the association between circRNA NRIP1 and miR-195-5p. The murine xenograft models were constructed to detect the roles of CircRNA NRIP1 and miR-195-5p. Western blot was applied to detect the effects of CircRNA NRIP1 and miR-195-5p on the P38 MAPK and JAK/STAT singling pathways.

RESULTS

CircRNA NRIP1 was over-expressed in PTC tissues and cells and the high levels of CircRNA NRIP1 were correlated with advanced PTC stage. Depletion of CircRNA NRIP1 inhibited PTC cell proliferation, invasion, while accelerated apoptosis. miR-195-5p upregulation repressed proliferation and invasion capabilities, and accelerated apoptosis of PTC cell lines and restraining the growth of tumor xenografts, while the functions were reversed following CircRNA NRIP1 overexpression in PTC cells and tumor xenografts. Besides, the protein levels of p-p38, p-JAK2 and p-STAT1 were remarkably down-regulated in miR-195-5p overexpressed PTC cells and tumor xenografts, whereas CircRNA NRIP1 up-regulation overturned the impacts.

CONCLUSIONS

In conclusion, CircRNA NRIP1 promoted PTC progression by accelerating PTC cells proliferation, invasion and tumor growth, while impeding apoptosis by way of sponging miR-195-5p and regulating the P38 MAPK and JAK/STAT pathways.

MiR-181a-5p Regulates NIS Expression in Papillary Thyroid Carcinoma

NIS is a potent iodide transporter encoded by the SLC5A5 gene. Its expression is reduced in papillary thyroid carcinoma (PTC). In this study we analyzed the impact of miR-181a-5p on NIS expression in the context of PTC. We used real-time PCR to analyze the expression of SLC5A5 and miR-181a-5p in 49 PTC/normal tissue pairs. Luciferase assays and mutagenesis were performed to confirm direct binding of miR-181a-5p to the 3′UTR of SLC5A5 and identify the binding site. The impact of modulation of miR-181a-5p using appropriate plasmids on endogenous NIS and radioactive iodine accumulation was verified. We confirmed downregulation of SLC5A5 and concomitant upregulation of miR-181a-5p in PTC. Broadly used algorithms did not predict the binding site of miR-181a-5p in 3′UTR of SLC5A5, but we identified and confirmed the binding site through mutagenesis using luciferase assays. In MCF7 and HEK293-flhNIS cell lines, transfection with mir-181a-expressing plasmid decreased endogenous SLC5A5, whereas silencing of miR-181a-5p increased it. We observed similar tendencies in protein expression and radioactive iodine accumulation. This study shows for the first time that miR-181a-5p directly regulates SLC5A5 expression in the context of PTC and may decrease efficacy of radioiodine treatment. Accordingly, miR-181a-5p may serve as an emerging target to enhance the efficacy of radioactive iodine therapy.

The Role of Snail-1 in Thyroid Cancer-What We Know So Far

Thyroid carcinomas, despite the usually indolent behaviour and relatively good overall prognosis, show a high tendency to gain invasive phenotype and metastasise in some cases. However, due to a relatively slow progression, the exact mechanisms governing the metastatic process of thyroid carcinomas, including the epithelial-to-mesenchymal transition (EMT), are poorly described. One of the best-known regulators of cancer invasiveness is Snail-1-a zinc-finger transcription factor that plays a key role as an EMT inducer. More and more attention is being paid to the role of Snail with regard to thyroid cancer development. Apart from the obvious implications in the EMT process, Snail-1 plays an important role in the regulation of chemoresistance of the thyroid cells and cancer stem cell (CSC) formation, and it also interacts with miRNA specific to the thyroid gland. The aim of this review was to summarise the knowledge on Snail-1, especially in the context of thyroid oncogenesis.

COL4A1, negatively regulated by XPD and miR-29a-3p, promotes cell proliferation, migration, invasion and epithelial-mesenchymal transition in liver cancer cells

OBJECTIVE

Collagen type IV alpha 1 (COL4A1) exerts tumor-promoting functions in several tumors. However, its role in liver cancer remains not fully understood. Hence, this study aims to investigate the role of COL4A1 in regulating liver cancer cell behaviors and to validate its upstream regulatory mechanism.

METHODS

Expression of xeroderma pigmentosum D (XPD) and COL4A1 was examined by qRT-PCR and western blot. Cell proliferation, migration, and invasion were evaluated. The protein levels of N-cadherin, vimentin, and E-cadherin were determined by western blot to evaluate epithelial-mesenchymal transition (EMT). The interaction between miR-29a-3p and COL4A1 was analyzed by luciferase reporter assay.

RESULTS

COL4A1 overexpression significantly promoted cell proliferation, migration, invasion, and EMT in Hep3B cells. In contrast, COL4A1 silencing yielded the opposite effects in HepG2 cells. Expression of COL4A1 was increased, whereas expression of XPD and miR-29a-3p was decreased in HCC tissues compared to controls. COL4A1 mRNA level was negatively correlated with expression of XPD and miR-29a-3p in HCC tissues. Furthermore, XPD silencing-mediated up-regulation of COL4A1 expression was attenuated by miR-29a-3p mimic. Moreover, miR-29a-3p mimic inhibited Hep3B cell proliferation, migration, and invasion by directly targeting COL4A1.

CONCLUSION

COL4A1 is negatively regulated by XPD-miR-29a-3p axis and promotes liver cancer progression in vitro.

Suppression of long noncoding RNA LINC00324 restricts cell proliferation and invasion of papillary thyroid carcinoma through downregulation of TRIM29 via upregulating microRNA-195-5p

Long noncoding RNAs (lncRNAs) are identified as novel regulators of carcinogenesis. To date, the precise functions of lncRNAs in papillary thyroid carcinoma (PTC) remains poorly understood. The purposes of this work were to explore the potential relevance of lncRNA 00324 (LINC00324) in PTC. Levels of LINC00324 were markedly up-regulated in PTC. Silencing of LINC00324 significantly repressed the proliferation and invasion of PTC cells. LINC00324 was documented as a sponge of microRNA-195-5p (miR-195-5p). Decreased levels of miR-195-5p were detected in PTC. The up-regulation of miR-195-5p suppressed PTC cellular proliferation and invasion. Suppression of miR-195-5p partially reversed the LINC00324-knockdown-mediated effects in PTC cells. We identified tripartite motif-containing 29 (TRIM29) as a target gene of miR-195-5p. TRIM29 overexpression partially reversed the LINC00324-knockdown- or miR-195-5p-overexpression-mediated effects in PTC cells. In short, this work demonstrates that LINC00324 knockdown inhibits the proliferation and invasion of PTC cells by decreasing TRIM29 expression via up-regulating miR-195-5p expression.

miR-146a-5p Plays an Oncogenic Role in NSCLC via Suppression of TRAF6

Non-small cell lung cancer (NSCLC) is the most deadly cancer in the world due to its often delayed diagnosis. Identification of biomarkers with high sensitivity, specificity, and accessibility for early detection, such as circulating microRNAs, is therefore of utmost importance. In the present study, we identified a significantly higher expression of miR-146a-5p in the serum and tissue samples of NSCLC patients than that of the healthy controls. In parallel, miR-146a-5p was also highly expressed in three human NSCLC adenocarcinoma-cell lines (A549, H1299, and H1975) compared to the human bronchial epithelium cell line (HBE). By dual-luciferase reporter assay and manipulation of the expressions of miR-146a-5p and its target gene, tumor necrosis factor receptor-associated factor 6 (TRAF6), we showed that the functional effects of miR-146a-5p on NSCLC cell survival and migration were mediated by direct binding to and suppression of TRAF6. Overexpression of TRAF6 sufficiently reversed miR-146a-5p-induced cancer cell proliferation, migration, and apoptosis resistance. Our data implied that miR-146a-5p/TRAF6/NF-κB-p65 axis could be a promising diagnostic marker and a therapeutic target for NSCLC.

Multifunctional Roles of miR-34a in Cancer: A Review with the Emphasis on Head and Neck Squamous Cell Carcinoma and Thyroid Cancer with Clinical Implications

MiR-34a belongs to the class of small non-coding regulatory RNAs and functions as a tumor suppressor. Under physiological conditions, miR-34a has an inhibitory effect on all processes related to cell proliferation by targeting many proto-oncogenes and silencing them on the post-transcriptional level. However, deregulation of miR-34a was shown to play important roles in tumorigenesis and processes associated with cancer progression, such as tumor-associated epithelial-mesenchymal transition, invasion, and metastasis. Moreover, further understanding of miR-34a molecular mechanisms in cancer are indispensable for the development of effective diagnosis and treatments. In this review, we summarized the current knowledge on miR-34a functions in human disease with an emphasis on its regulation and dysregulation, its role in human cancer, specifically head and neck squamous carcinoma and thyroid cancer, and emerging role as a disease diagnostic and prognostic biomarker and the novel therapeutic target in oncology.

The role of microRNAs in the pathogenesis of thyroid cancer

Thyroid cancer is the most frequent type of cancers originating from the endocrine system. Early diagnosis leads to good clinical outcome in differentiated types of thyroid cancer. Yet, there are few treatment options for patients with medullary or anaplastic thyroid cancer. Thus, identification of molecular markers that explain the pathologic process during evolution of this cancer has practical significance. MicroRNAs (miRNAs) have been shown to influence the activity of thyroid cancer-related signaling pathways such as MAPK pathway and RET gene. These small transcripts not only can differentiate malignant tissues from non-malignant tissues, but also have differential expression in different stages of thyroid cancer. Assessment of serum levels of miRNAs is a practical noninvasive method for follow-up of patients after thyroidectomy. Moreover, the therapeutic effects of a number of miRNAs have been verified in xenograft models of thyroid cancer. In the current review, we summarize the data regarding the role of miRNAs in thyroid cancer.

Expression based biomarkers and models to classify early and late-stage samples of Papillary Thyroid Carcinoma

INTRODUCTION

Recently, the rise in the incidences of thyroid cancer worldwide renders it to be the sixth most common cancer among women. Commonly, Fine Needle Aspiration biopsy predominantly facilitates the diagnosis of the nature of thyroid nodules. However, it is inconsiderable in determining the tumor's state, i.e., benign or malignant. This study aims to identify the key RNA transcripts that can segregate the early and late-stage samples of Thyroid Carcinoma (THCA) using RNA expression profiles.

MATERIALS AND METHODS

In this study, we used the THCA RNA-Seq dataset of The Cancer Genome Atlas, consisting of 500 cancer and 58 normal (adjacent non-tumorous) samples obtained from the Genomics Data Commons (GDC) data portal. This dataset was dissected to identify key RNA expression features using various feature selection techniques. Subsequently, samples were classified based on selected features employing different machine learning algorithms.

RESULTS

Single gene ranking based on the Area Under the Receiver Operating Characteristics (AUROC) curve identified the DCN transcript that can classify the early-stage samples from late-stage samples with 0.66 AUROC. To further improve the performance, we identified a panel of 36 RNA transcripts that achieved F1 score of 0.75 with 0.73 AUROC (95% CI: 0.62-0.84) on the validation dataset. Moreover, prediction models based on 18-features from this panel correctly predicted 75% of the samples of the external validation dataset. In addition, the multiclass model classified normal, early, and late-stage samples with AUROC of 0.95 (95% CI: 0.84-1), 0.76 (95% CI: 0.66-0.85) and 0.72 (95% CI: 0.61-0.83) on the validation dataset. Besides, a five protein-coding transcripts panel was also recognized, which segregated cancer and normal samples in the validation dataset with F1 score of 0.97 and 0.99 AUROC (95% CI: 0.91-1).

CONCLUSION

We identified 36 important RNA transcripts whose expression segregated early and late-stage samples with reasonable accuracy. The models and dataset used in this study are available from the webserver CancerTSP (http://webs.iiitd.edu.in/raghava/cancertsp/).

miR-424-5p Promotes Anoikis Resistance and Lung Metastasis by Inactivating Hippo Signaling in Thyroid Cancer

miR-424-5p has been widely identified to function as an oncomiR in multiple human cancer types. However, the biological function of miR-424-5p in distant metastasis of thyroid cancer, as well as the underlying mechanism, remains not clarified yet. In the current study, miR-424-5p expression was elucidated in 10 paired fresh thyroid cancer tissues and the thyroid cancer dataset from The Cancer Genome Atlas (TCGA). Lung metastasis colonization models in vivo and functional assays in vitro were used to determine the role of miR-424-5p in thyroid cancer. Bioinformatics analysis, western blot, luciferase reporter, and immunofluorescence assays were applied to identify the potential targets and underlying mechanism involved in the functional role of miR-424-5p in lung metastasis of thyroid cancer. Here, we reported that miR-424-5p was upregulated in thyroid cancer, and overexpression of miR-424-5p significantly correlated with distant metastasis of thyroid cancer. Upregulating miR-424-5p promoted, whereas silencing miR-424-5p inhibited, anoikis resistance in vitro and lung metastasis in vivo. Mechanistic investigation further revealed that miR-424-5p promoted anoikis resistance and lung metastasis by inactivating Hippo signaling via simultaneously targeting WWC1, SAV1, and LAST2. Therefore, our results support the idea that miR-424-5p may serve as a potential therapeutic target in lung metastasis of thyroid cancer.

Molecular Signature of Prospero Homeobox 1 (PROX1) in Follicular Thyroid Carcinoma Cells

The prospero homeobox 1 (PROX1) transcription factor is a product of one of the lymphangiogenesis master genes. It has also been suggested to play a role in carcinogenesis, although its precise role in tumour development and metastasis remains unclear. The aim of this study was to gain more knowledge on the PROX1 function in thyroid tumorigenesis. Follicular thyroid cancer-derived cells—CGTH-W-1—were transfected with PROX1-siRNA (small interfering RNA) and their proliferation, cell cycle, apoptosis and motility were then analysed. The transcriptional signature of PROX1 depletion was determined using RNA-Sequencing (RNA-Seq) and the expression of relevant genes was further validated using reverse transcriptase quantitative PCR (RT-qPCR), Western blot and immunocytochemistry. PROX1 depletion resulted in a decreased cell motility, with both migratory and invasive potential being significantly reduced. The cell morphology was also affected, while the other studied cancer-related cell characteristics were not significantly altered. RNA-seq analysis revealed significant changes in the expression of transcripts encoding genes involved in both motility and cytoskeleton organization. Our transcriptional analysis of PROX1-depleted follicular thyroid carcinoma cells followed by functional and phenotypical analyses provide, for the first time, evidence that PROX1 plays an important role in the metastasis of thyroid cancer cells by regulating genes involved in focal adhesion and cytoskeleton organization in tumour cells.

MicroRNA-221 promotes papillary thyroid carcinoma cell migration and invasion via targeting RECK and regulating epithelial-mesenchymal transition

Aim

The aim of this study was to detect the effects and potential mechanisms of microRNA-221 on a series of biological behaviors of papillary thyroid carcinoma (PTC) cells in vitro and in vivo.

Methods

First, we analyzed the relationship between the expression of miR-221 and several clinicopathological features of PTC patients and then detected the expression of the miR-221 in tumor tissues and cell lines. The effects of miR-221 on proliferation and invasion of PTC cells were verified by cell counting kit-8 (CCK-8) assay, wound healing assay and transwell assay. Western blot assay was applied to explore the correlation between miR-221 and RECK expression in PTC K1 cells. Finally, a xenograft model was established to further confirm the tumor-promoting effects of miR-221 in vivo.

Results

Our data indicated that miR-221 was relatively upregulated in metastatic PTC tissues. MiR-221 promoted the proliferation, migration and invasion activities of PTC K1 cells, following variations of epithelial-mesenchymal transition (EMT)-related protein expression. We identified RECK as a direct target of miR-221, revealed its expression to be inversely correlated with miR-221 in PTC samples and showed that its reintroduction reverses miR-221-induced PTC invasiveness. In addition, miR-221 was also verified to promote tumor growth and increase tumor volume and weight in vivo. Taken together, miR-221/RECK axis could be an effective way to regulate biological behaviors of PTC.

Conclusion

MiR-221 may be involved in PTC cell invasion and metastasis by targeting RECK, indicating that the miR-221/RECK pathway could be studied further as a potential new diagnostic or prognostic biomarker for PTC.

Identification of Biomarkers Based on Differentially Expressed Genes in Papillary Thyroid Carcinoma

The incidence of papillary thyroid carcinoma (PTC) is increasing rapidly throughout the world. Hence, there is an urgent need for identifying more specific and sensitive biomarkers to explorate the pathogenesis of PTC. In this study, three pairs of stage I PTC tissues and matched normal adjacent tissues were sequenced by RNA-Seq, and 719 differentially expressed genes (DEGs) were screened. KEGG pathway enrichment analyses indicated that the DEGs were significantly enriched in 28 pathways. A total of 18 nodes consisting of 20 DEGs were identified in the top 10% of KEGG integrated networks. The functions of DEGs were further analysed by GO. The 13 selected genes were confirmed by qRT-PCR in 16 stage I PTC patients and by The Cancer Genome Atlas (TCGA) database. The relationship interactions between DEGs were analysed by protein-protein interaction networks and chromosome localizations. Finally, four newly discovered genes, COMP, COL3A1, ZAP70, and CD247, were found to be related with PTC clinical phenotypes, and were confirmed by Spearman’s correlation analyses in TCGA database. These four DEGs might be promising biomarkers for early-stage PTC, and provide an experimental foundation for further exploration of the pathogenesis of early-stage PTC.

Clinical significance of microRNA-449a in hepatocellular carcinoma with microarray data mining together with initial bioinformatics analysis

Increasing evidence has demonstrated that microRNA (miR)-449a expression is reduced in various types of tumors and that it serves as a tumor suppressor. However, the molecular mechanism of miR-449a in hepatocellular carcinoma (HCC) has not been thoroughly elucidated and is disputed. Therefore, the aim of the present work was to systematically review the current literature and to utilize the public Gene Expression Omnibus database to determine the role of miR-449a and its significance in HCC. A total of eight original papers and seven microarrays were included in the present study. Based on the evidence, miR-449a was reduced in HCC. miR-449a is likely involved in various signaling pathways and is targeted to multiple mRNA as part of its function in HCC. In addition, a preliminary bioinformatic analysis was conducted for miR-449a to investigate the novel potential pathways that miR-449a may participate in regarding HCC.

Clinical significance of miR-34a expression in thyroid diseases - an 18F-FDG PET-CT study

Purpose

To evaluate the possible roles of miR-34a expression in thyroid lesions, to unravel the correlation between fluorodeoxyglucose (FDG) uptake and miR-34a expression and moreover, to discover the underlying mechanisms by which miR-34a regulates FDG avidity.

Methods

We retrospectively reviewed 75 patients with pathology-confirmed thyroid diseases who underwent ¹⁸F-FDG positron emission tomography/computed tomography (PET/CT) within 3 months before undergoing thyroid surgery and miR-34a analysis from June 2012 to July 2017. ¹⁸F-FDG uptake of thyroid lesions was also analyzed semiquantitatively using maximum standardized uptake value (SUVmax). The association between miR-34a expression and clinicopathological variables (age, sex, TNM stage, histopathology, lesion numbers, location and ¹⁸F-FDG avidity) was investigated. When there were multiple lesions in thyroid bed, only the one with the highest ¹⁸F-FDG uptake was analyzed. Next, we inhibited the miR-34a expression in TPC-1 cells and detected the expression of glucose transporter 1 (GLUT1) mRNA and protein.

Results

In the patients cohort, miR-34a was upregulated in those with malignant thyroid diseases compared with benign lesions. The expression of miR-34a was associated with tumor stages, histopathological types and SUVmax. There was an inverse relationship between miR-34a expression and SUVmax in patients with thyroid diseases (Spearman correlation coefficient = −0.553, P < 0.0001). With an SUVmax of 4.3 as the threshold, sensitivity and specificity of the prediction of miR-34a expression (low or high) were 70% and 94.3%, respectively. The area under the receiver operating characteristic curve was 0.843 (95% confidence interval: 0.749, 0.936; P = 0.001). Inhibiting miR-34a in TPC-1 cells significantly increased GLUT1 mRNA and protein expression.

Conclusion

miR-34a expression was upregulated in thyroid lesions, negatively correlated with SUVmax and can be predicted by FDG SUVmax. In addition, miR-34a may regulate FDG avidity via targeting GLUT1.

hsa-miR-29c-3p regulates biological function of colorectal cancer by targeting SPARC

Colorectal cancer (CRC) is the most common type of behavioral cancers, miRNAs play a critical role in cancer development and progression. In the present study, we downloaded the original data from Gene Expression Omnibus (GEO) and conduct data analysis. has-mir-29c-3p mimic, inhibitor, negative control or si-SPARC (secreted protein acidic, rich in cysteine) were transfected into HCT116 cells, respectively. Quantitative real time PCR (qRT-PCR) was used to measure has-mir-29c-3p and SPARC mRNA expressions, western blot was used to detect ACAA1 (acetyl-CoA acyltransferase 1), ACOX1 (acyl-CoA oxidase 1), COL1A1(collagen, type I, alpha-1), COL1A2 (collagen, type I, alpha-2), COL4A1 (collagen, type IV, alpha-1), COL5A2 (collagen, type V, alpha-2), COL12A1 (collagen, type XII, alpha-1), CPT2 (carnitine palmitoyltransferase 2), ETHE1 (persulfide dioxygenase), HMGCS2 (3-hydroxy-3-methylglutaryl-CoA synthase 2), SPARC, SQRDL (sulfide quinone oxidoreductase), and TST (thiosulfate sulfurtransferase) protein expression. CCK-8 and wound healing assay were employed to verify cell proliferation and migration. The luciferase reporter assay data made sure the target correlation of has-mir-29c-3p and SPARC. Firstly, we found that the expression of has-mir-29c-3p was lower in CRC tissues than in their paired corresponding non-cancerous tissues and there was significant inversed correlation between has-mir-29c-3p and SPARC. Overexpression of has-mir-29c-3p reduced cell proliferation and migration. SPARC was identified as a direct target of has-mir-29c-3p, whose silencing reduced cell proliferation and migration. These data showed that has-mir-29c-3p regulates CRC cell functions through regulating SPARC expression. Taken together, has-mir-29c-3p may function as an oncogenic miRNA targeting SPARC, targeted modulation of has-mir-29c-3p expression may became a potential strategy for the treatment.

Novel biomarker SYT12 may contribute to predicting papillary thyroid cancer outcomes

Aim:

To investigate biomarkers for predicting papillary thyroid cancer outcomes.

Materials & methods:

The expression of biomarkers (ITGA2, SYT12 and CDH3) was studied in a prospective cohort of patients with papillary thyroid cancer. Three outcomes of initial metastases, baseline status and longitudinal status were analyzed and correlated with the biomarkers.

Results:

SYT12 provided the best prediction of initial metastasis (sensitivity: 72%; specificity: 54%). SYT12 had the highest accuracy for predicting longitudinal status (sensitivity: 100%; specificity: 47%). The best performance for longitudinal status resulted from combining SYT12 with American Thyroid Association risk stratification, with sensitivity and specificity of 88 and 73%, respectively.

Conclusion:

SYT12 has some prognostic significance in papillary thyroid cancer. Further validation studies in larger populations are warranted.

Survival and disease recurrence after diagnosis of papillary thyroid cancer is imperfectly predicted by commonly used ‘staging systems’ based mostly on the characteristics of the tumor such as size and location of spread. Also, these staging systems are generally designed to predict survival. Other characteristics, such as gene mutations may be helpful in predicting whether thyroid cancer will behave aggressively or not. This study investigates three genes associated with thyroid tumors and shows that expression of one of them, synaptotagmin 12 (SYT12), tends to predict greater progression of disease in patients with papillary thyroid cancer.

Serum miRNAs as Biomarkers for the Diagnosis and Prognosis of Thyroid Cancer: A Comprehensive Review of the Literature

BACKGROUND/OBJECTIVES

Thyroid cancer is the most common endocrine malignancy and accounts for 1% of cancers. In recent years, there has been much interest in the feasibility of using miRNAs or miRNA panels as biomarkers for the diagnosis of thyroid cancer. miRNAs are noncoding RNAs with 21-23 nucleotides that are highly conserved during evolution. They have been proposed as regulators of gene expression, apoptosis, cancer, and cell growth and differentiation.

METHODS

The Directory of Open Access Journals (DOAJ), Google Scholar, PubMed (NLM), LISTA (EBSCO), and Web of Science were searched.

RESULTS

The serum level of miRNAs (miRNA-375, 34a, 145b, 221, 222, 155, Let-7, 181b) can be used as molecular markers for the diagnosis and prognosis of thyroid cancer in the serum samples of patients with thyroid glands.

CONCLUSIONS

Given that most common methods for the screening of thyroid cancer cannot detect the disease in its early stages, identifying miRNAs that are released in the bloodstream during the gradual progression of the disease is considered a key method in the early diagnosis of thyroid cancers.

Wnt signaling pathway protein LEF1 in cancer, as a biomarker for prognosis and a target for treatment

Transcription factors are regulatory proteins that either activate or repress the transcription of genes via binding to DNA regulatory sequences and regulating recruitment of transcriptional complexes. Lymphoid enhancer-binding factor 1 (LEF1), a member of the T-cell Factor (TCF)/LEF1 family of high-mobility group transcription factors, is a downstream mediator of the Wnt/β-catenin signaling pathway, but can also modulate gene transcription independently. LEF1 is essential in stem cell maintenance and organ development, especially in its role in epithelial-mesenchymal transition (EMT) by activating the transcription of hallmark EMT effectors including N-Cadherin, Vimentin, and Snail. Aberrant expression of LEF1 is implicated in tumorigenesis and cancer cell proliferation, migration, and invasion. LEF1's activity in particular cancer cell types, such as chronic lymphocytic leukemia (CLL), Burkitt lymphoma (BL), acute lymphoblastic leukemia (ALL), oral squamous cell carcinoma (OSCC), and colorectal cancer (CRC), makes it a valuable biomarker in predicting patient prognosis. Additionally, due to aberrant LEF1 activity resulting in cancer progression, knockdown and inhibition treatments designed to target LEF1 have proven effective in alleviating cancer growth, migration, and invasion in CLL, CRC, glioblastoma multiforme (GBM), and renal cell carcinoma (RCC). In prostate cancer cells, LEF1 promotes androgen receptor expression and activity in an androgen-independent manner, ultimately increasing prostate cancer growth regardless of androgen ablation therapy. In this review, we review LEF1 regulation, its role in tumorigenesis in several cancer types, and its clinical value as a biomarker for predicting prognoses and as a target for treatment.

Primary Thyroid Carcinoma with Low-Risk Histology and Distant Metastases: Clinicopathologic and Molecular Characteristics

BACKGROUND

Distant metastases (DM) are a rare occurrence in well-differentiated thyroid carcinoma. The aim of this study was to analyze the clinical, pathologic, and molecular features of primary thyroid carcinoma with low-risk histology that develop DM.

METHODS

A detailed clinicopathologic review and targeted next-generation sequencing were performed on a cohort of well-differentiated thyroid carcinoma lacking gross extrathyroidal extension, extensive vascular invasion, or significant lymph node metastases but exhibiting DM.

RESULTS

Primary well-differentiated thyroid carcinoma with low-risk histologic features and DM was a rare occurrence, accounting for only 3% of metastatic non-anaplastic thyroid carcinoma. All 15 cases meeting the inclusion criteria harbored DM at presentation. The majority (11/15) of these tumors were follicular variant of papillary thyroid carcinoma (PTC), especially the encapsulated form (n = 8). The remaining patients harbored encapsulated Hürthle cell carcinoma (n = 2), encapsulated follicular carcinoma (n = 1), and an encapsulated papillary carcinoma classical variant (n = 1). Of the 12 encapsulated carcinomas, 10 had capsular invasion only and no vascular invasion. Ninety-two percent of the tumors exhibited extensive intra-tumoral fibrosis. Among the eight tumors that were subjected to next-generation sequencing analysis, a RAS mutation was the main driver (5/8), and TERT promoter mutation was highly prevalent (6/8). In four cases, TERT promoter mutations were associated with RAS or BRAF mutations. BRAF-mutated classical variant of papillary carcinoma also presented with DM but was less common (1/8). In 11/15 cases, the clinician was able to diagnose distant disease based on the clinical presentation. In 3/4 incidental cases that were genotyped, TERT promoter mutations were found.

CONCLUSIONS

When DM occur in primary thyroid carcinoma with low-risk histology, they are almost always found at presentation. The majority are encapsulated follicular variant of PTC with capsular invasion only. TERT promoter mutations occur at a higher rate than that seen in PTC in general and may help explain the aggressive behavior of these histologically deceptive primary carcinomas.

The highly expressed COL4A1 genes contributes to the proliferation and migration of the invasive ductal carcinomas

BACKGROUND

Invasive ductal carcinoma is a kind of very typical breast cancer. The goal of our research was to figure out the molecular mechanism of Invasive ductal carcinoma and to find out its potential therapy targets.

RESULTS

The total amount of 478 differentially expressed genes in Invasive ductal carcinoma which compared with normal breast epithelial cells were recognized. Functional enrichment analysis proved the most part of differentially expressed genes had connection with ECM-receptor interaction. The two genes lists were contrasted in PPI network, and miRNA regulation networks, The most two crucial genes were identified in our study, which may be helpful to improve Invasive ductal carcinoma treatment. Additionally, experimental results shows that the COL4A1 gene, one of identified genes, played important roles in both of proliferation and colony formation in Invasive ductal carcinoma.

CONCLUSIONS

Invasive ductal carcinoma could have connection with ECM-receptor mutations. These 9 vital genes could be an important part in the progression of Invasive ductal carcinoma and be offered as therapy targets and prognosis indicator. and the experimental results showed that one of the most crucial genes, COL4A1, was the key gene that influence the proliferation and colony formation of the Invasive ductal carcinoma cell.

Dynamic monitoring of circulating microRNAs as a predictive biomarker for the diagnosis and recurrence of papillary thyroid carcinoma

Circulating microRNAs (miRNAs/miRs) are considered to be potential biomarkers for numerous types of cancer. However, previous investigations into the expression of miRNAs in the serum of patients with papillary thyroid carcinoma (PTC) to predict diagnosis, prognosis and recurrence have reported conflicting results, and the role of miRNAs remains unclear. The present study dynamically assessed the circulating miRNA profile in patients with PTC and determined whether miRNAs in the serum could be used as biomarkers for the diagnosis, prognosis and recurrence of PTC. The expression levels of 3 reportedly upregulated miRNAs (miR-222, miR-221 and miR-146b) were analyzed using reverse transcription-quantitative polymerase chain reaction in 106 patients with PTC, 35 patients with benign thyroid nodules (BTN) and 40 paired controls. Patients with either newly diagnosed PTC or BTN who were undergoing thyroidectomies were recruited for a dynamic analysis of preoperative and postoperative serum miRNA levels. The results indicated that the expression levels of serum miR-222, miR-221 and miR-146b were significantly increased in patients with newly diagnosed PTC compared with controls and patients with BTN. Receiver operating characteristic curve analysis indicated that these miRNAs had a high diagnostic sensitivity and specificity for PTC prior to surgery. The expression of these three miRNAs in serum was significantly associated with poorer prognostic variables, including extrathyroidal invasion, metastatic lymph nodes and high-risk or advanced tumor node metastasis stage. More notably, the present study identified 2.36-, 2.69- and 5.39-fold reductions in the serum levels of miR-222, miR-221 and miR-146b, respectively, subsequent to patients undergoing a thyroidectomy. In addition, miR-222, miR-221 and miR-146b were overexpressed in the PTC with recurrence group compared with the PTC without recurrence group. Collectively, dynamic monitoring of circulating miRNAs may serve as a non-invasive biomarker for the diagnosis of PTC and the postoperative monitoring of its progression and recurrence.

VDR mRNA overexpression is associated with worse prognostic factors in papillary thyroid carcinoma

The purpose of this study was to assess the relationship between vitamin D receptor gene (VDR) expression and prognostic factors in papillary thyroid cancer (PTC). mRNA sequencing and somatic mutation data from The Cancer Genome Atlas (TCGA) were analyzed. VDR mRNA expression was compared to clinicopathologic variables by linear regression. Tree-based classification was applied to find cutoff and patients were split into low and high VDR group. Logistic regression, Kaplan-Meier analysis, differentially expressed gene (DEG) test and pathway analysis were performed to assess the differences between two VDR groups. VDR mRNA expression was elevated in PTC than that in normal thyroid tissue. VDR expressions were high in classic and tall-cell variant PTC and lateral neck node metastasis was present. High VDR group was also associated with classic and tall cell subtype, AJCC stage IV and lower recurrence-free survival. DEG test reveals that 545 genes were upregulated in high VDR group. Thyroid cancer-related pathways were enriched in high VDR group in pathway analyses. VDR mRNA overexpression was correlated with worse prognostic factors such as subtypes of papillary thyroid carcinoma that are known to be worse prognosis, lateral neck node metastasis, advanced stage and recurrence-free survival.

Knockdown of Long Non-Coding RNA KCNQ1OT1 Restrained Glioma Cells' Malignancy by Activating miR-370/CCNE2 Axis

Accumulating evidence has highlighted the potential role of long non-coding RNAs (lncRNAs) as biomarkers and therapeutic targets in solid tumors. Here, we elucidated the function and possible molecular mechanisms of lncRNA KCNQ1OT1 in human glioma U87 and U251 cells. Quantitative Real-Time polymerase chain reaction (qRT-PCR) demonstrated that KCNQ1OT1 expression was up-regulated in glioma tissues and cells. Knockdown of KCNQ1OT1 exerted tumor-suppressive function in glioma cells. Moreover, a binding region was confirmed between KCNQ1OT1 and miR-370 by dual-luciferase assays. qRT-PCR showed that miR-370 was down-regulated in human glioma tissue and cells. In addition, restoration of miR-370 exerted tumor-suppressive function via inhibiting cell proliferation, migration and invasion, while promoting the apoptosis of human glioma cells. Knockdown of KCNQ1OT1 decreased the expression level of Cyclin E2 (CCNE2) by binding to miR-370. Further, miR-370 bound to CCNE2 3′UTR region and decreased the expression of CCNE2. These results provided a comprehensive analysis of KCNQ1OT1-miR-370-CCNE2 axis in human glioma cells and might provide a novel strategy for glioma treatment.

MicroRNA-146b: A Novel Biomarker and Therapeutic Target for Human Papillary Thyroid Cancer

Papillary thyroid cancer (PTC) is the most common tumor subtype of thyroid cancer. However, not all PTCs are responsive to current surgical and radioiodine treatment. The well-established clinical prognostic factors include tumor size, lymph node/distal metastasis, and extrathyroidal invasion. The RET/PTC-RAS-BRAF linear molecular signaling cascade is known to mediate PTC pathogenesis. However, whether presence of BRAF mutation, the most common genetic alteration in PTC, can affect PTC behavior and prognosis is controversial. MicroRNAs (miRNAs) have been labeled as promising molecular prognostic markers in several tumor types. Our recent studies demonstrated that microRNA-146b (miR-146b) deregulation is associated with PTC aggressiveness and prognosis. Here we summarize the current knowledge related to the functional roles, regulated target genes, and clinical applications of miR-146b in PTC and discuss how these studies provide insights into the key role of miR-146b as an oncogenic regulator promoting cellular transformation as well as a prognosis marker for tumor recurrence in PTC. In conjunction with the current perspectives on miRNAs in a wide variety of human cancers, this review will hopefully translate these updated findings on miR-146b into more comprehensive diagnostic or prognostic information regarding treatment in PTC patients before surgical intervention and follow up strategies.

MicroRNA-363-3p inhibits papillary thyroid carcinoma progression by targeting PIK3CA

MicroRNA-363-3p (miR-363-3p) reportedly plays crucial roles in tumor development and progression in many types of cancers. However, its role in papillary thyroid carcinoma (PTC) remain largely unclear. We therefore investigated the function and underlying mechanism of miR-363-3p in PTC. Here, we found that miR-363-3p was significantly downregulated in human PTC tissue samples and cell lines, and that miR-363-3p levels are negatively correlated with advanced clinical stage and lymph node metastasis. In addition to suppressing tumor growth in vivo, restoration of miR-363-3p in TPC-1 cells significantly inhibits proliferation, migration, and invasion and induced apoptosis in vitro. Mechanistically, miR-363-3p was verified to directly bind to 3'UTR of the phosphoinositide-3-kinase catalytic subunit alpha (PIK3CA) mRNA, and reduce its expression at both mRNA and protein levels, which further inhibits phosphatidylinositol 3-kinase/Akt signaling pathway. PIK3CA expression was also found to be increased in human PTC tissues, and were inversely correlated with miR-363-3p. Furthermore, restoration of PIK3CA partially rescued the miR-363-3p-induced inhibition effect on TPC-1 cell proliferation, migration and invasion. Taken together, these findings indicated for the first time that miR-363-3p functions as a tumor suppressor in PTC, and its suppressive effect is mediated by repressing PIK3CA.

MiR-195 Inhibits Tumor Growth and Metastasis in Papillary Thyroid Carcinoma Cell Lines by Targeting CCND1 and FGF2

BACKGROUND

MicroRNA (miRNA) dysregulation was commonly seen in papillary thyroid carcinoma (PTC), and miR-195 was verified to be downregulated in PTC by the large data set analysis from The Cancer Genome Atlas (TCGA). Our study aimed to explore the biological functions and the underlying molecular mechanisms of miR-195 in PTC.

METHODS

The relative expression of miR-195 and its target genes were assessed by quantitative RT-PCR assay in 38 pairs of PTC and the adjacent thyroid tissues. Assays were performed to evaluate the effect of miR-195 on the proliferation, migration, and invasion in PTC cell lines. Moreover, we searched for targets of miR-195 and explored the possible molecular pathway of miR-195 in PTC.

RESULTS

We found that miR-195 was downregulated in PTC cell lines and tissues. Overexpression of miR-195 significantly inhibited cell proliferation, migration, and invasion in K1 and BCPAP cell lines. CCND1 and FGF2, which had inverse correlations with miR-195 in clinical specimens, were found to be the direct targets of miR-195. Furthermore, miR-195 might be involved in PTC tumorigenesis by suppressing the Wnt/β-catenin signaling pathway.

CONCLUSIONS

These results highlight an important role of miR-195 in the initiation and progression of PTC and implicate the potential application of miR-195 in PTC target therapy.

miRNA expression profiling of 'noninvasive follicular thyroid neoplasms with papillary-like nuclear features' compared with adenomas and infiltrative follicular variants of papillary thyroid carcinomas

Follicular variants of papillary thyroid carcinoma include encapsulated (with or without capsular/vascular invasion) and infiltrative forms, which have different clinical behaviors. The encapsulated forms that lack capsular invasion have an indolent clinical behavior that is similar to benign lesions; therefore, they were recently reclassified as 'noninvasive follicular thyroid neoplasms with papillary-like nuclear features' (NIFTPs). Because NIFTPs have nuclear features of papillary carcinomas, distinguishing between NIFTPs and infiltrative follicular variant of papillary thyroid carcinoma is almost impossible with cytological examination. The aim of this study is to determine whether miRNA expression profiles may help distinguish between NIFTPs versus follicular adenomas and infiltrative follicular variant of papillary thyroid carcinomas. The expression profiling of 798 miRNAs was tested in 54 thyroid tumors, including 18 follicular adenomas, 19 NIFTPs and 17 infiltrative follicular variant of papillary thyroid carcinomas, using nCounter Nanostring. We found that miR-146-5p, miR-221-5p, miR-222-3p, miR-30e-3p, and miR-152-3p could discriminate between benign and malignant lesions with a very high level of significance (P-value<0.001). High expression levels of miR-146-5p, miR-199a-5p, miR-199b-5p, miR-1285-5p, miR-1915-3p, and miR-4516, and low miR-148b-3p expression were associated with infiltrative growth of follicular variant of papillary thyroid carcinomas. Interestingly, miR-152-3p, miR-185-5p, and miR-574-3p were significantly downregulated in NIFTPs compared with follicular adenomas, whereas miR-10a-5p and miR-320e can discriminate between NIFTPs and infiltrative forms of follicular variant of papillary thyroid carcinomas. In conclusion, a panel of these markers could have high diagnostic potential as well as could be applied to presurgical fine-needle aspiration, especially for lesions classified as indeterminate thyroid nodules.

MiR-146a suppresses hepatocellular carcinoma by downregulating TRAF6

MicroRNAs have been proven to play important roles in many biological processes such as cellular growth and differentiation, apoptosis, and modulation of host response to viral infection. In the present study, we find that the expression of miR-146a was decreased in hepatocellular carcinoma (HCC) tissues compared with corresponding adjacent tissues, and the expression level in HCC cell lines was lower than in a normal liver cell. Over-expression suppressed the proliferation and invasion of HCC cells. In addition, luciferase reporter assays and western blotting confirmed that miR-146a directly target TRAF6 which attenuated the effect of miR-146a on cell proliferation and invasion in HepG2 and SMMC7721 cells. Meanwhile, lentivirus-mediated increased expression of miR146a repressed tumor formation in nude mice. Taken together, our findings demonstrate that miR-146a suppresses HCC by down-regulating TRAF6. We also discovered that miR-146a may represent a novel potential candidate of the HCC carcinoma diagnostic marker in the long term.

Multicentre validation of a microRNA-based assay for diagnosing indeterminate thyroid nodules utilising fine needle aspirate smears

AIMS

The distinction between benign and malignant thyroid nodules has important therapeutic implications. Our objective was to develop an assay that could classify indeterminate thyroid nodules as benign or suspicious, using routinely prepared fine needle aspirate (FNA) cytology smears.

METHODS

A training set of 375 FNA smears was used to develop the microRNA-based assay, which was validated using a blinded, multicentre, retrospective cohort of 201 smears. Final diagnosis of the validation samples was determined based on corresponding surgical specimens, reviewed by the contributing institute pathologist and two independent pathologists. Validation samples were from adult patients (≥18 years) with nodule size >0.5 cm, and a final diagnosis confirmed by at least one of the two blinded, independent pathologists. The developed assay, RosettaGX Reveal, differentiates benign from malignant thyroid nodules, using quantitative RT-PCR.

RESULTS

Test performance on the 189 samples that passed quality control: negative predictive value: 91% (95% CI 84% to 96%); sensitivity: 85% (CI 74% to 93%); specificity: 72% (CI 63% to 79%). Performance for cases in which all three reviewing pathologists were in agreement regarding the final diagnosis (n=150): negative predictive value: 99% (CI 94% to 100%); sensitivity: 98% (CI 87% to 100%); specificity: 78% (CI 69% to 85%).

CONCLUSIONS

A novel assay utilising microRNA expression in cytology smears was developed. The assay distinguishes benign from malignant thyroid nodules using a single FNA stained smear, and does not require fresh tissue or special collection and shipment conditions. This assay offers a valuable tool for the preoperative classification of thyroid samples with indeterminate cytology.