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

Circulating miR-206, miR-181b, and miR-21 as promising biomarkers in hypothyroidism and their relationship to related hyperlipidemia and hepatic steatosis

Background: Thyroid hormones (THs) signaling has profound effects on many physiological processes. The regulation of THs signaling in various tissues involves the action of microRNAs (miRNAs) on thyroid deiodinases and receptors. THs regulate the expression of certain miRNAs and their target messenger RNAs (mRNAs) in various tissues and cells. The modulation of miRNA levels by THs affects their functions in processes such as liver lipid metabolism, skin physiology, and muscle and heart performance. Aim: This research aimed to investigate miR-181b, miR-206, and miR-21 in the serum of patients with subclinical and overt hypothyroidism to determine their possible role in the diagnosis of the disease and their relationship to clinical disorders related to hypothyroidism. Methods: This study included ninety participants, divided evenly into three groups as follows: patients with overt hypothyroidism diagnosed clinically, radiologically, and by investigation, subclinical hypothyroid patients, and healthy volunteers. The patients had a thorough medical history and underwent a clinical examination. Laboratory tests included plasma cholesterol, LDL, HDL, TGs, liver and renal function tests, CBC, fasting insulin, HOMA-IR, HbA1c, TSH, and free T4. The serum levels of miR-21, miR-206, and miR-181b were measured using qRT-PCR. Results: miR-206 and miR-181b levels were higher in the subclinical group, followed by the hypothyroid and control groups. For miR-21, there was a significantly lower mean value in both the hypothyroid and subclinical groups than in the control group, with no difference between the two groups. Both miR-206 and miR-181b showed a significant negative association with albumin and free T4 levels and a significant direct association with GGT, ALT, AST, creatinine, uric acid, TGs, TC, LDL, TSH, thyroid volume, and CAP score. The same correlation pattern was observed for miR-181b, except that it was not significantly correlated with the TGs. For miR-21 levels, there was a significant positive correlation with albumin, free T4 level, and kPa score and a negative correlation with GGT, ALT, AST, creatinine, uric acid, HOMA-IR, HbA1c, TC, LDL, TSH, and CAP score. Cases with F1 kPa score and S2 CAP scores had significantly higher averages for miR-206 and miR-181b, with a p-value of 0.05. Moreover, miR-21 levels were significantly lower in the S2 CAP score group. Conclusion: These miRNAs (miR-206, miR-181b, and miR-21) may be used as diagnostic biomarkers for hypothyroidism. They may be used as therapeutic targets to control dyslipidemia and hepatic steatosis during hypothyroid disease.

Chromatin-Accessible miRNA Regulons Driving Thyroid Tumorigenesis and Progression

BACKGROUND

Although papillary thyroid cancer can remain indolent, associated lymph node metastases and recurrence rates are approximately 50% and 20%, respectively. Omics-based medicine has led to the discovery of predictive biomarkers that can be used to predict tumor progression and clinical outcomes. We aimed to develop a noninvasive omics-driven blood test to allow accurate risk stratification and help tailor individual patient treatment plans.

STUDY DESIGN

RNA sequencing (seq) and microRNA analysis of The Cancer Genome Atlas and Gene Expression Omnibus datasets were employed to identify an epigenetic prognostic panel. Integrated bulk assay for transposase-accessible chromatin-seq and RNA-seq experiments confirmed the results. Sixty-two paired tumor and adjacent control thyroid tissues and 67 blood samples (62 papillary thyroid cancer and 5 controls) were analyzed for validation using sequencing and real-time polymerase chain reaction and correlated to clinical outcomes. A liposome-exosome fusion clustered regularly interspaced short palindromic repeats (CRISPR)-fluorescent detection system miRNA assay was developed. A predictive risk nomogram was generated and tested for performance.

RESULTS

Our miRNA panel (miR-146b-5p and miR-221-3p) from tissue and blood was associated with aggressive features and was located within accessible chromatin regions. The miRNA risk score and prognostic nomogram showed higher accuracy in predicting lymph node metastases (miR-146b: area under the curve [AUC] 0.816, sensitivity 76.9%; miR-221: AUC 0.740, sensitivity 79.5%) and recurrence (miR-146b: AUC 0.921, sensitivity 75.0%; miR-221: AUC 0.756, sensitivity 70.0%; p < 0.001) than staging and American Thyroid Association risk stratification. CRISPR-based miRNA assays showed upregulation in the blood of cancer cohorts.

CONCLUSIONS

CRISPR-based detection of miR-146b and miR-221 in the blood of thyroid cancer patients is a reliable and noninvasive tool for real-time assessment and prognostication that has great potential to provide a direct impact on the care of these 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.

Circulating microRNAs and Clinicopathological Findings of Papillary Thyroid Cancer: A Systematic Review

BACKGROUND/AIM

Papillary thyroid cancer (PTC) is the most common endocrine malignancy with a rising incidence. There is a need for a non-invasive preoperative test to enable better patient counselling. The aim of this systematic review was to investigate the potential role of circulating microRNAs (miRNAs) in the diagnosis and prognosis of PTC.

MATERIALS AND METHODS

A systematic literature search was performed using MEDLINE, Cochrane, and Scopus databases (last search date was December 1, 2021). Studies investigating the expression of miRNAs in the serum or plasma of patients with PTC were deemed eligible for inclusion.

RESULTS

Among the 1,533 screened studies, 39 studies met the inclusion criteria. In total, 108 miRNAs candidates were identified in the serum, plasma, or exosomes of patients suffering from PTC. Furthermore, association of circulating miRNAs with thyroid cancer-specific clinicopathological features, such as tumor size (13 miRNAs), location (3 miRNAs), extrathyroidal extension (9 miRNAs), pre- vs. postoperative period (31 miRNAs), lymph node metastasis (17 miRNAs), TNM stage (9 miRNAs), BRAF V600E mutation (6 miRNAs), serum thyroglobulin levels (2 miRNAs), ¹³¹I avid metastases (13 miRNAs), and tumor recurrence (2 miRNAs) was also depicted in this study.

CONCLUSION

MiRNAs provide a potentially promising role in the diagnosis and prognosis of PTC. There is a correlation between miRNA expression profiles and specific clinicopathological features of PTC. However, to enable their use in clinical practice, further clinical studies are required to validate the predictive value and utility of miRNAs as biomarkers.

Development and Validation of a Novel Circulating miRNA-Based Diagnostic Score for Early Detection of Hepatocellular Carcinoma

BACKGROUND

With the rise of liquid biopsy in oncology, circulating miRNAs have become one of the most promising noninvasive biomarkers for early detection of hepatocellular carcinoma (HCC). However, a reliable HCC-related circulating miRNA panel and corresponding diagnostic model remain to be explored.

METHODS

Five large public datasets related to intact miRNA profiles in the serum or tumors of HCC patients were included and divided into training cohorts (GSE113740 and TCGA-LIHC) and validation cohorts (GSE112264, GSE113486 and GSE106817). Compared with non-cancer controls and high-risk patients, key miRNAs dysregulated in both the serum and tumors of HCC patients were identified by differential expression analysis and overlapping analysis. The corresponding diagnostic model was constructed by LASSO logistic regression and evaluated by receiver operating characteristic curves and a nomogram with calibration plot.

RESULTS

A distinctive panel of HCC-related circulating miRNAs, including three upregulated miRNAs (miR-184, miR-532-5p, miR-221-3p) and three downregulated miRNAs (miR-5589-5p, let-7b-3p, miR-26b-3p), were rigorously screened out, all of which displayed significant discriminability between HCC patients and controls (all P < 0.05). In addition, a reliable six-circulating miRNA-based diagnostic score was constructed and displayed robust diagnostic ability for HCC (particularly for early-stage HCC) (AUC = 0.9535, P < 0.05) compared with that of the serum α-fetoprotein test. Importantly, its efficacy was sufficiently validated in three independent datasets (AUC = 0.9780/0.9961/0.9681, all P < 0.05). Furthermore, a visual nomogram based on the diagnostic score was correspondingly established to strengthen its clinical applicability.

CONCLUSION

The six-circulating miRNA-based diagnostic score may be a reliable noninvasive biomarker for early-stage HCC screening and dynamic monitoring of postoperative recurrence.

CircSND1/miR-182-5p Axis Promotes Proliferative and Invasive Abilities of Thyroid Cancer via Binding Targeting MET

Objective. To monitor the impacts of circSND1 upon thyroid cancer (TC) tissues and cells and its mechanisms. Methods. Thiazole blue (MTT) was adopted to monitor the impacts of circSND1 upon the proliferative abilities of TPC-1 and SW1736 cells. 5-Bromodeoxyuridine (BrdU) combined with flow cytometry was adopted to monitor the impacts of circSND1 upon the DNA synthesis of TPC-1 and SW1736 cells. We adopted transwell experiment to examine the impacts of circSND1 on cell invasive abilities of TPC-1 and SW1736 cells. The mRNA quantitative levels of circSND1, miR-182-5p, and mesenchymal epidermal transformation factor (MET) in TC tissues were detected by qRT-PCR experiment. We also adopted luciferase assay to verify the targeting interaction between miR-182-5p and MET or miR-182-5p and circSND1. Results. CircSND1 mRNA and MET mRNA were upregulated in thyroid cancer tissues. MiR-182-5p quantification was attenuated in thyroid cancer tissues. Downregulation of circSND1 suppressed TC progression in vivo and in vitro. Furthermore, luciferase report assay uncovered that miR-182-5p was a direct binding target of circSND1 and MET was a direct binding target of miR-182-5p. Besides, circSND1 regulated MET expression and thyroid cancer cell function via binding miR-182-5p. Conclusion. Overexpression of circSND1 in TC tissues and cells facilitates TC tumorigenesis and metastasis via suppressing the quantitative level of miR-182-5p and inducing the upregulation of MET mRNA and protein expression, which expected to offer fresh clues for the administration of TC.

Expression Profile and Diagnostic Significance of MicroRNAs in Papillary Thyroid Cancer

The incidence of papillary thyroid cancer (PTC) has increased in recent years. To improve the diagnostic management of PTC, we propose the use of microRNAs (miRNAs) as a biomarker. Our aim in this study was to evaluate the miRNA expression pattern in PTC using NanoString technology. We identified ten miRNAs deregulated in PTC compared with reference tissue: miR-146b-5p, miR-221-3p, miR-221-5p, miR-34-5p, miR-551b-3p, miR-152-3p, miR-15a-5p, miR-31-5p, and miR-7-5p (FDR < 0.05; |fold change (FC)| ≥ 1.5). The gene ontology (GO) analysis of differentially expressed miRNA (DEM) target genes identified the predominant involvement of epidermal growth factor receptor (EGFR), tyrosine kinase inhibitor resistance, and pathways in cancer in PTC. The highest area under the receiver operating characteristic (ROC) curve (AUC) for DEMs was found for miR-146-5p (AUC = 0.770) expression, indicating possible clinical applicability in PTC diagnosis. The combination of four miRNAs (miR-152-3p, miR-221-3p, miR-551b-3p, and miR-7-5p) showed an AUC of 0.841. Validation by real-time quantitative polymerase chain reactions (qRT-PCRs) confirmed our findings. The introduction of an miRNA diagnostic panel based on the results of our study may help to improve therapeutic decision making for questionable cases. The use of miRNAs as biomarkers of PTC may become an aspect of personalized medicine.

Identification of Exosomal microRNAs and Their Targets in Papillary Thyroid Cancer Cells

The release of molecules in exosomal cargoes is involved in tumor development and progression. We compared the profiles of exosomal microRNAs released by two thyroid cancer cell lines (TPC-1 and K1) with that of non-tumorigenic thyroid cells (Nthy-ori-3-1), and we explored the network of miRNA–target interaction. After extraction and characterization of exosomes, expression levels of microRNAs were investigated using custom TaqMan Advanced array cards, and compared with those expressed in the total cell extracts. The functional enrichment and network-based analysis of the miRNAs’ targets was also performed. Five microRNAs (miR-21-5p, miR-31-5p, miR-221-3p, miR-222-3p, and let-7i-3p) were significantly deregulated in the exosomes of tumor cells vs. non-tumorigenic cells, and three of them (miR-31-5p, miR-222-3p, and let-7i-3p) in the more aggressive K1 compared to TPC-1 cells. The network analysis of the five miRNAs identified some genes as targets of more than one miRNAs. These findings permitted the identification of exosomal microRNAs secreted by aggressive PTC cells, and indicated that their main targets are regulators of the tumor microenvironment. A deeper analysis of the functional role of the targets of exosomal miRNAs will provide further information on novel targets of molecular treatments for these neoplasms.

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.

Analysis of serum microRNA in exosomal vehicles of papillary thyroid cancer

PURPOSE

In this study, we investigated the profile of microRNAs (miRNAs) contained in exosomes secreted in the serum of patients with papillary thyroid cancer (PTC).

METHODS

Exosome were isolated by adding ExoQuick Exosome Precipitation Solution. Dynamic light scattering (DLS) and western blotting analysis were used to ensure the quality of exosomes. The expression levels of miRNAs were investigated using custom-designed TaqMan Advanced miRNA Array Cards in the screening cohort and using specific TaqMan Advanced MicroRNA Assays in the validation cohort.

RESULTS

We identified miR24-3p, miR146a-5p, miR181a-5p and miR382-5p with different expression levels in two different series of 56 and 58 PTC patients as compared with healthy controls. Significant differences in the expression of three PTC exosomal miRNAs, depending on the presence of lymph node metastasis, were detected in only one PTC series. When comparing the expression levels of some PTC-specific exosomal miRNAs with those of the same miRNAs circulating free of any encapsulation, we found a significant correlation for only miR24-3p, suggesting that only select miRNAs are secreted in exosomes.

CONCLUSIONS

Our findings demonstrate that four miRNAs are differently secreted in the exosomes of PTC patients, whereas no conclusive results were found to characterize PTCs with lymph node metastasis, suggesting caution in the use of circulating exosomal miRNA expression levels as lymph node metastasis biomarkers. Further investigation into the mechanisms governing miRNA secretion in tumor cells are required.

Epigenetic Silencing of SOX15 Is Controlled by miRNAs rather than Methylation in Papillary Thyroid Cancer

Methods

In this study, qRT-PCR was used to investigate the expression levels of the SOX15 gene and of miR-182, miR-183, miR-375, and miR-96 in thyroid tumors and adjacent noncancerous tissues. We also investigated the methylation status of the SOX15 promoter by methylation-specific PCR in tumors and adjacent noncancerous tissues.

Results

We observed a statistically significant downregulation of SOX15 expression in tumors compared to noncancerous tissue samples. The methylation levels of tumors and matched noncancerous tissues were similar, but miR-182, miR-183, and miR-375 expression levels were elevated in tumor tissues compared to noncancerous tissue samples.

Conclusions

Our results indicate that SOX15 gene expression is associated with the pathogenesis of papillary thyroid carcinoma (PTC), and the epigenetic control of the SOX15 gene is regulated by miRNAs rather than by promoter methylation.

MiR-192-5p inhibits proliferation, migration, and invasion in papillary thyroid carcinoma cells by regulation of SH3RF3

Background: The decreased level of miR-192-5p has been reported in several kinds of cancers, including bladder, colon, ovarian, and non-small cell lung cancer. However, the expression and function of miR-192-5p in papillary thyroid carcinoma/cancer (PTC) remains unknown.

Objective: The present study aimed to explore the function and underlying mechanism of miR-192-5p in PTC development.

Methods: PTC tissues and relative normal controls from PTC patients were collected. qRT-PCR analysis was performed to measure miR-192-5p and SH3RF3 mRNA level in PTC tissues and cell lines. CCK-8 method and FCM assay were used to test cell proliferation and apoptosis in TPC-1 cells, respectively. The abilities of cell migration and invasion were detected by wound healing and transwell assays, respectively. The protein expression was evaluated by Western blot. The interaction between miR-192-5p and Src homology 3 (SH3) domain containing ring finger 3 (SH3RF3) were confirmed by dual-luciferase reporter assay.

Results: MiR-192-5p level was obviously decreased in PTC tissues and cell lines. Overexpression of miR-192-5p suppressed proliferation, migration, invasion, and EMT process, while induced apoptosis in TPC-1 cells. In addition, miR-192-5p negatively modulated SH3RF3 expression by binding to its 3′-untranslated region (3′UTR). Silencing SH3RF3 inhibited the migration, invasion, and EMT of TPC-1 cells. In the meantime, matrine, an alkaloid extracted from herb, exerted its anti-cancer effects in PTC cells dependent on increase in miR-192-5p expression and decrease in SH3RF3 expression.

Conclusion: We firstly declared that miR-192-5p played a tumor suppressive role in PTC via targeting SH3RF3. Moreover, matrine exerted its anti-cancer effects in PTC via regulating miR-192-5p/SH3RF3 pathway.

A meta-analysis of circulating microRNAs in the diagnosis of papillary thyroid carcinoma

Background

Aim of this meta-analysis was to evaluate the overall diagnostic value of circulating mini miRNAs for papillary thyroid carcinoma (PTC) and to find the possible molecular marker with higher diagnostic value for PTC.

Methods

We searched the Pubmed, Cochrane and Embase database until June 2020. We selected relevant literatures associated with the diagnosis of PTC with circulating miRNAs. The number of cases in experimental group and the control group, sensitivity and specificity could be extracted from the literatures.

Results

We got 9 literatures including 2114 cases of PTC. Comprehensive sensitivity was 0.79, comprehensive specificity was 0.82, positive likelihood ratio was 4.3, negative likelihood ratio was 0.26, diagnostic advantage ratio was 16. The summary receiver operating characteristic curve was drawn and the Area Under the Curve was 0.87.

Conclusions

Circulating microRNAs may be promising molecular markers for the diagnosis of papillary thyroid carcinoma. Combined detection of certain serum microRNAs can improve the diagnostic accuracy of papillary thyroid carcinoma. Especially MiR-222 and miR-146b may be prime candidates for the diagnosis of PTC in Asian population.

Papillary Thyroid Carcinoma Tissue miR-146b, -21, -221, -222, -181b Expression in Relation with Clinicopathological Features

We analyzed miR-146b, miR-21, miR-221, miR-21, and miR-181b in formalin fixed paraffin-embedded papillary thyroid carcinoma (PTC) tissue samples of 312 individuals and evaluated their expression relationship with clinicopathological parameters. A higher expression of miR-21 was related to unifocal lesions (p < 0.011) and autoimmune thyroiditis (0.007). miR-221, miR-222 expression was higher in the PTC tissue samples with extrathyroidal extension (p = 0.049, 0.003, respectively). In a group of PTC patients with pT1a and pT1b sized tumors, the expression of miR-146b, miR-21, miR-221, and miR-222 in PTC tissue samples was lower than in patients with pT2, pT3, and pT4 (p = 0.032; 0.0044; 0.003; 0.001; 0.001, respectively). Patients with lymph node metastases had higher expression of miR-21, -221, -222, and -181b (p < 0.05). A high expression of miR-146b, miR-21, miR-221 panel was associated with decreased overall survival (OS) (Log rank p = 0.019). Univariate analysis revealed that presence of metastatic lymph nodes and high expression of miR-146b, miR-21, and miR-221 panels were associated with increased hazard of shorter OS. After multivariate analysis, only sex (male) and age (≥55 years) emerged as independent prognostic factors associated with shorter OS (HR 0.28 (95% CI 0.09–0.86) and HR 0.05 (95% CI 0.01–0.22), respectively). In conclusion, 5 analyzed miRs expression have significant relations to clinicopathologic parameters so further investigations of these molecules are expedient while searching for prognostic PTC biomarkers.

Prognostic and Immune-Infiltrate Significance of miR-222-3p and Its Target Genes in Thyroid Cancer

Thyroid cancer (THCA) is a common endocrine malignancy. With increasing incidence and low mortality, balancing the therapeutic approach is an inevitable issue. This study aimed to confirm the role of miR-222-3p and its target genes in THCA survival and immune infiltration. From different expression analyses based on the GEO and TCGA databases, we predicted and subsequently identified the key target genes of miR-222-3p. We then explored the expression, enrichment, pairwise correlation, protein expression, survival analysis, principal component analysis, and immune significance of the critical genes using bioinformatics analysis. The present study demonstrated that NEGR1, NTNG1, XPNPEP2, NTNG2, CD109, OPCML, and PRND are critical genes. The miR-222-3p was highly expressed, probably leading to low NEGR1 and high PRND expression in THCA tissues. Low NEGR1 expression indicated favorable prognosis in THCA patients, and high PRND expression indicated poor prognosis. Seven critical genes were significantly related to gender, age, race, tumor stage, and lymph node metastasis. In addition, the seven-gene biomarker exhibited a certain diagnostic value. Finally, CD109 expression was closely correlated with immune cells, especially B cells and CD4⁺ T cells. The miR-222-3p and its critical target genes could be promising biomarkers for the prognosis of THCA and may emerge as key regulators of immune infiltration in THCA.

Biomarker Value of miR-221 and miR-222 as Potential Substrates in the Differential Diagnosis of Papillary Thyroid Cancer Based on Data Synthesis and Bioinformatics Approach

BACKGROUND

MicroRNA (miRNA) has been reported to play a critical regulatory role in papillary thyroid carcinomas (PTC). However, the role of miR-221/222 in PTC remains unclear. Here, we performed this study to explore the diagnostic potentials and mechanisms of miR-221/222 in PTC.

METHODS

First, we systematically analyzed the diagnostic value of miR-221/222 in the diagnosis PTC by pooling the published studies. Afterwards, we performed comprehensive bioinformatics analysis including gene ontology analysis, pathway enrichment analysis and protein-protein interaction analysis to explore the potential mechanisms of miR-221/222 involved in PTC.

RESULTS

The overall sensitivity and specificity of miR-221/222 for PTC were 0.75 (95% CI: 0.70-0.80) and 0.80 (95% CI: 0.76-0.84) respectively with the AUC of 0.85 (95% CI: 0.81-0.88). The diagnostic performance varied among different subgroups including geographical locations, sample sources and sample sizes. Meanwhile, we found that a combination of miR-221/222 and other miRNAs when used in a diagnostic panel could improve the diagnostic accuracy than individual miR-221/222. Moreover, through the bioinformatics analysis, we confirmed that miR-221/222 targets were highly related to the molecular pathogenesis of PTC. The results revealed that miR-221/222 may exert important functions in PTC through thyroid hormone signaling pathway and some other key pathways by regulating some key genes.

CONCLUSION

These findings indicated that miR-221/222 have the potential to serve as auxiliary tools for diagnosing PTC. Further prospective clinical trials should be performed to assess the accuracy of these findings in a larger cohort and determine the clinical uses.

miRNA Expression Analysis: Cell Lines HCC1500 and HCC1937 as Models for Breast Cancer in Young Women and the miR-23a as a Poor Prognostic Biomarker

PURPOSE

The study of breast cancer nearly always involves patients close to menopause or older. Therefore, young patients are mostly underrepresented. Our aim in this study was to demonstrate biological differences in breast cancer of young people using as a model available cell lines derived from people with breast cancer younger than 35 years.

METHODS

Global miRNA expression was analyzed in breast cancer cells from young (HCC1500, HCC1937) and old patients (MCF-7, MDA-MB-231, HCC1806, and MDA-MB-468). In addition, it was compared with same type of results from patients.

RESULTS

We observed a differential profile for 155 miRNAs between young and older cell lines. We identified a set of 24 miRNA associated with aggressiveness that were regulating pluripotency of stem cell-related pathways. Combining the miRNA expression data from cell lines and breast cancer patients, 132 miRNAs were differently expressed between young and old samples, most of them previously found in cell lines. MiR-23a-downregulation was also associated with poor survival in young patients.

CONCLUSIONS

Our results suggest that HCC1500 and HCC1937 cell lines could be suitable cellular models for breast cancer affecting young women. The miR-23a-downregulation could have a potential role as a poor prognosis biomarker in this age group.

MicroRNA in Papillary Thyroid Carcinoma: A Systematic Review from 2018 to June 2020

Simple Summary

The most common form of endocrine cancer - papillary thyroid carcinoma, has an increasing incidence. Although this disease usually has an indolent behavior, there are cases when it can evolve more aggressively. It has been known for some time that it is possible to use microRNAs for the diagnosis, prognosis and even treatment monitoring of papillary thyroid cancer. The purpose of this study is to summarize the latest information provided by publications regarding the involvement of microRNAs in papillary thyroid cancer, underling the new clinical perspectives offered by these publications.

Abstract

The involvement of micro-ribonucleic acid (microRNAs) in metabolic pathways such as regulation, signal transduction, cell maintenance, and differentiation make them possible biomarkers and therapeutic targets. The purpose of this review is to summarize the information published in the last two and a half years about the involvement of microRNAs in papillary thyroid carcinoma (PTC). Another goal is to understand the perspective offered by the new findings. Main microRNA features such as origin, regulation, targeted genes, and metabolic pathways will be presented in this paper. We interrogated the PubMed database using several keywords: “microRNA” + “thyroid” + “papillary” + “carcinoma”. After applying search filters and inclusion criteria, a selection of 137 articles published between January 2018–June 2020 was made. Data regarding microRNA, metabolic pathways, gene/protein, and study utility were selected and included in the table and later discussed regarding the matter at hand. We found that most microRNAs regularly expressed in the normal thyroid gland are downregulated in PTC, indicating an important tumor-suppressor action by those microRNAs. Moreover, we showed that one gene can be targeted by several microRNAs and have nominally described these interactions. We have revealed which microRNAs can target several genes at once.

Diagnostic value of circulating microRNAs in thyroid carcinoma: A systematic review and meta-analysis

BACKGROUND AND OBJECTIVE

Thyroid cancer (TC) is the most common endocrine system tumour. Several studies had revealed the potential of circulating microRNAs (miRNAs) as novel biomarkers for the diagnosis of TC. The purpose of this meta-analysis is to summarize published studies and evaluate the diagnostic accuracy of circulating miRNAs in TC detection.

METHODS

In this meta-analysis, we systematically searched three databases: PubMed, EMBASE and Cochrane Library. We used the bivariate mixed-effects regression model to calculate the pooled diagnostic parameters and conduct the summary receiver operator characteristic curve (SROC). All calculations were performed using stata software.

RESULTS

Thirty-five studies from 9 articles, including 663 TC patients, 519 patients with benign thyroid nodules (BTNs), and 84 healthy controls were included in this meta-analysis. The pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR) and area under the SROC curve (AUC) were 0.81 (95% CI 0.75-0.86), 0.81 (95% CI 0.75-0.86), 4.3 (95% CI 3.2-5.6), 0.24 (95% CI 0.18-0.31), 18 (95% CI 12-28) and 0.88 (95% CI 0.85-0.90), respectively in BTN controls, and 0.81 (95% CI 0.75-0.86), 0.85 (95% CI 0.75-0.91), 5.3 (95% CI 3.3-8.7), 0.23 (95% CI 0.18-0.29), 24 (95% CI 14-39), 0.89 (95% CI 0.86-0.91) in healthy controls. The subgroup analysis found that multiple miRNA assays had higher diagnostic accuracy than single miRNA assays with sensitivity of 0.88, specificity of 0.89 and AUC of 0.94.

CONCLUSION

Circulating miRNAs have good values to diagnose TC and distinguish TC patients from BTN patients. MiRNAs can assist in the diagnosis of malignancy and avoid unnecessary surgery. In summary, circulating miRNAs should be added to our current clinical tools.

The Prognostic Value of MicroRNAs in Thyroid Cancers-A Systematic Review and Meta-Analysis

Thyroid cancer (TC) includes various phenotypes, from indolent to highly aggressive cancer. The limitations of the current prognostication systems to predict the recurrence risk and the variability in expression of the genes involved in the thyroid carcinogenesis uncover the need for new prognostic biomarkers by taking into account potential epigenetic differences. We aimed to summarize the current knowledge regarding the prognostic impact of microRNAs (miRNAs) in TC. A literature search was conducted in PubMed, Embase, Scopus, and Web of Science databases. Both upregulated and downregulated miRNAs are significantly correlated with worse overall survival (hazard ratio (HR) = 5.94, 95% CI: 2.73-12.90, p < 0.001; HR = 0.51, 95% CI: 0.26-0.96, p = 0.048) disease/recurrence-free survival (HR = 1.58, 95% CI: 1.08-2.32, p = 0.003; HR = 0.37, 95%, CI: 0.24-0.60, p < 0.001). Sensitivity analysis revealed a significant association between the higher expression of miR-146b, miR-221, and miR-222 and the recurrence of papillary TC (OR = 9.11, 95% CI 3.00 to 27.52; p < 0.001; OR = 3.88, 95% CI 1.34 to 11.19, p < 0.001; OR = 6.56, 95% CI 2.75 to 15.64, p < 0.001). This research identified that miR-146b, miR-221, and miR-222 could serve as potential prognostic biomarkers in TC, particularly in PTC. Further studies are needed to strengthen these findings and sustain its clinical applicability.

Plasma-Derived miRNA-222 as a Candidate Marker for Papillary Thyroid Cancer

We analyzed five miRNA molecules (miR-221; miR-222; miR-146b; miR-21; miR-181b) in the plasma of patients with papillary thyroid cancer (PTC), nodular goiter (NG) and healthy controls (HC) and evaluated their diagnostic value for differentiation of PTC from NG and HC. Preoperative PTC plasma miRNA expression (n = 49) was compared with plasma miRNA in the HC group (n = 57) and patients with NG (n = 23). It was demonstrated that miR-221; miR-222; miR-146b; miR-21 and miR-181b were overexpressed in preoperative PTC plasma samples compared to HC (p < 0.0001; p < 0.0001; p < 0.0001; p < 0.0001; p < 0.002; respectively). The upregulation in tumor tissue of these miRNAs was consistent with The Cancer Genome Atlas Thyroid Carcinoma dataset. A significant decrease in miR-21; miR-221; miR-146b and miR-181b expression was observed in the plasma of PTC patients after total thyroidectomy (p = 0.004; p = 0.001; p = 0.03; p = 0.036; respectively). The levels of miR-222 were significantly higher in the preoperative PTC compared to the NG group (p = 0.004). ROC curve (receiver operating characteristic curve) analysis revealed miR-222 as a potential marker in distinguishing PTC from NG (AUC 0.711; p = 0.004). In conclusion; circulating miR-222 profiles might be useful in discriminating PTC from NG.

A Panel of Plasma Exosomal miRNAs as Potential Biomarkers for Differential Diagnosis of Thyroid Nodules

Background: A liquid biopsy using circulating exosomal genetic materials provides new insights for thyroid cancer diagnosis. This study aimed to identify plasma-derived exosomal biomarkers that could be used for early detection of papillary thyroid carcinoma (PTC).

Method: Exosomal miRNAs in plasma were isolated from patients with benign thyroid nodules and patients with PTC. Profiling of exosomal miRNA was performed using RNA sequencing (RNA-seq) to identify miRNA candidates and differentiate the benign from malignant. The validation cohort consisted of 30 patients with benign thyroid nodules, 35 PTC patients, and 31 healthy individuals. Real-time PCR was used to quantify the expression of miRNA candidates. The diagnostic potential of the candidates was evaluated by receiver operating characteristic (ROC) curves.

Results: After RNA-seq, eight plasma exosomal miRNAs were selected as candidates. Further validation indicated that the levels of exosomal miR-16-2-3p, miR-223-5p, miR-34c-5p, miR-182-5p, miR-223-3p, and miR-146b-5p were significantly lower in nodules compared to healthy controls (p < 0.0001), whereas miR-16-2-3p and miR-223-5p were significantly higher in the PTC cases than in those with benign nodules (p < 0.05). ROC analyses revealed that the above six miRNAs were potent indicators for detection of thyroid nodules. Meanwhile, miR-16-2-3p and miR-223-5p can be utilized for detecting PTC from benign nodules. Additionally, combined miRNA panels showed increased diagnostic sensitivities and specificities compared to single miRNA markers.

Conclusion: Six aberrantly expressed plasma exosomal miRNAs may be used as diagnostic biomarkers to differentiate thyroid nodules from healthy individuals. The panel consisting of miR-16-2-3p, miR-223-5p, miR-101-3p, and miR-34c-5p are eligible for discriminating benign from malignant thyroid nodules.

Noncoding RNAs in Extracellular Fluids as Cancer Biomarkers: The New Frontier of Liquid Biopsies

The last two decades of cancer research have been devoted in two directions: (1) understanding the mechanism of carcinogenesis for an effective treatment, and (2) improving cancer prevention and screening for early detection of the disease. This last aspect has been developed, especially for certain types of cancers, thanks also to the introduction of new concepts such as liquid biopsies and precision medicine. In this context, there is a growing interest in the application of alternative and noninvasive methodologies to search for cancer biomarkers. The new frontiers of the research lead to a search for RNA molecules circulating in body fluids. Searching for biomarkers in extracellular body fluids represents a better option for patients because they are easier to access, less painful, and potentially more economical. Moreover, the possibility for these types of samples to be taken repeatedly, allows a better monitoring of the disease progression or treatment efficacy for a better intervention and dynamic treatment of the patient, which is the fundamental basis of personalized medicine. RNA molecules, freely circulating in body fluids or packed in microvesicles, have all the characteristics of the ideal biomarkers owing to their high stability under storage and handling conditions and being able to be sampled several times for monitoring. Moreover, as demonstrated for many cancers, their plasma/serum levels mirror those in the primary tumor. There are a large variety of RNA species noncoding for proteins that could be used as cancer biomarkers in liquid biopsies. Among them, the most studied are microRNAs, but recently the attention of the researcher has been also directed towards Piwi-interacting RNAs, circular RNAs, and other small noncoding RNAs. Another class of RNA species, the long noncoding RNAs, is larger than microRNAs and represents a very versatile and promising group of molecules which, apart from their use as biomarkers, have also a possible therapeutic role. In this review, we will give an overview of the most common noncoding RNA species detectable in extracellular fluids and will provide an update concerning the situation of the research on these molecules as cancer biomarkers.

Elevated serum concentrations of IGF-1 and IGF-1R in patients with thyroid cancers

BACKGROUND

The rising incidence of thyroid cancer observed in the last few decades requires an improvement in diagnostic tools and management techniques for patients with thyroid nodules.

AIMS

The aim of this study was to assess serum concentrations of IGF-1 and IGF-1R in patients diagnosed with thyroid cancers.

METHODS

36 patients diagnosed with papillary thyroid cancer (PTC), 11 subjects with follicular thyroid cancer (FTC), 9 patients with anaplastic thyroid cancer (ATC) and 19 subjects with multinodular nontoxic goiter (MNG) were enrolled to the study. The control group (CG) consisted of 20 healthy volunteers. Blood samples were collected one day before surgery. Serum IGF-1 and IGF-1R concentrations were measured using specific ELISA methods.

RESULTS

Significantly higher concentrations of IGF-1 were found in patients with PTC as compared with controls but not that obtained from subjects diagnosed with MNG. The concentration of IGF-1R was significantly elevated in subjects with PTC and ATC as compared with healthy volunteers. Similarly, patients diagnosed with PTC or ATC presented significantly higher serum concentration of IGF-1R in comparison to the MNG group.

CONCLUSIONS

Our results show that the IGF-1 - IGF-1R axis plays a significant role in the development of PTC and ATC and imply that serum concentrations of both cytokines may be considered as additional markers for the differentiation of malignancies during the preoperative diagnosis of patients with thyroid gland tumors. These results indicate that IGF-1R serum concentrations allow us to differentiate between MNG and PTC or ATC. Moreover IGF-1R serum values appear to be better predictor of PTC and ATC than IGF-1 concentrations.

BRAF V600E mutation and microRNAs are helpful in distinguishing papillary thyroid malignant lesions: Tissues and fine needle aspiration cytology cases

AIMS

Mutations of BRAF oncogene are considered to contribute in the invasiveness and poor clinicopathologic features of papillary thyroid cancer (PTC). As a step towards understanding the underlying molecular mechanisms of this contribution, we aimed to examine the association of four microRNAs' (miR-222, -137, -214, -181b) levels with BRAFV600E and clinicopathological features in PTC tissues and fine needle aspiration (FNA) specimens.

METHODS

In total, 56 PTC and 27 benign with multinodular goiter tissue samples, 95 FNA samples, and B-CPAP and HEK293 cell lines were examined. BRAFV600E mutation was examined in PTC tissues and FNA samples. Expression of microRNAs was assessed by real-time quantitative reverse transcription-PCR.

KEY FINDINGS

The frequency of BRAFV600E in PTC tissues and FNA samples "suspicious for PTC" was 41.1 and 36.8%, respectively. MiR-222, -137, -214, and -181b were significantly upregulated in PTC tumors (P < 0.05) and in B-CPAP cell line (P < 0.001). In FNA, the expressions of miR-222, -181b and -214 were significantly elevated in patients suspected for PTC (P < 0.05), while there was no significant difference in miR-137. After adjustment for age and sex, miR-181b was associated with an increased risk of bearing BRAFV600E mutation (OR: 1.27; 95% CI: 1.01-1.61; P = 0.045) and risk of lymphovascular invasion (OR: 1.66; 95% CI: 1.01-2.72; P = 0.045); miR-137 was associated with the risk of larger tumor size (OR: 1.31; 95% CI: 1.04-1.65; P = 0.022); miR-222 was related to increase in extracapsular invasion (OR: 1.28; 95% CI: 1.04-1.57; P = 0.018).

SIGNIFICANCE

Upregulation of miR-222, -214 and -181b has been confirmed in PTC tumors, FNA samples and cell line. MiR-137 upregulation has been confirmed in PTC tumors and cell line, but not in FNA samples. MiR-222, -137 and -181b showed an association with the degree of malignancy in PTC tumors.

Blood Circulating miRNAs as Cancer Biomarkers for Diagnosis and Surgical Treatment Response

miRNAs can function as potential oncogenes or tumor suppressors. Altered expression of these molecules was correlated with the occurrence of many cancer diseases and therefore they are considered a molecular tool for non-invasive cancer diagnosis and prognosis. We searched for analyses concerning expression of blood circulating miRNA in cancer patients. The studies comprised of at least two miRNA expression measurements: before and after the surgical therapy were considered. We summarized latest reports on evaluation of the efficiency of anticancer therapy through observation of changes in expression of miRNA circulating in blood of patients treated with surgery alone. Twenty one research studies were identified. Thirty one different miRNAs were pointed out as potential both diagnostic and treatment response biomarkers since their deregulated expression before therapy returned to normal after receiving the treatment. Published data revealed a potential of circulating miRNA to become a tool giving a clinical follow up information on the efficiency of applied therapy. However, more observational studies on post-operative circulating miRNA expression changes are necessary.

Current controversies and future directions in the diagnosis and management of differentiated thyroid cancers

Despite the development of novel diagnostic, surgical, and chemotherapeutic approaches to differentiated thyroid cancers (DTCs), the diagnosis and management of these tumors remains controversial. The most recent American Thyroid Association (ATA) guidelines, released in 2015, reflect a recent shift towards less aggressive management for patients with DTCs. However, many clinicians have expressed concern that more conservative management will put patients at risk for disease recurrence and metastasis. In particular, the management of indeterminate nodules on fine needle aspiration (with special attention to genetic and epigenetic markers of malignancy), the extent of surgery for known differentiated cancers, the role of adjuvant radioactive iodine (RAI) therapy, and novel targeted treatments with tyrosine kinase inhibitors (TKIs) represent current areas of uncertainty and opportunities for future research. In this review, we examine the current state of the art in these areas, and address some of the questions that remain.