TSHR intronic polymorphisms (rs179247 and rs12885526) and their role in the susceptibility of the Brazilian population to Graves' disease and Graves' ophthalmopathy

Graves disease: latest understanding of pathogenesis and treatment options

Graves disease is the most common cause of hyperthyroidism in iodine-sufficient areas. The main responsible mechanism is related to autoantibodies that bind and activate the thyrotropin receptor (TSHR). Although Graves hyperthyroidism is relatively common, no causal treatment options are available. Established treatment modalities are antithyroid drugs, which reduce thyroid hormone synthesis, radioactive iodine and surgery. However, emerging drugs that target the main autoantigen (monoclonal antibodies, small molecules, peptides) or block the immune pathway have been recently tested in clinical trials. Graves disease can involve the thyroid exclusively or it can be associated with extrathyroidal manifestations, among which Graves orbitopathy is the most common. The presence of Graves orbitopathy can change the management of the disease. An established treatment for moderate-to-severe Graves orbitopathy is intravenous glucocorticoids. However, recent advances in understanding the pathogenesis of Graves orbitopathy have allowed the development of new target-based therapies by blocking pro-inflammatory cytokine receptors, lymphocytic infiltration or the insulin-like growth factor 1 receptor (IGF1R), with several clinical trials providing promising results. This article reviews the new discoveries in the pathogenesis of Graves hyperthyroidism and Graves orbitopathy that offer several important tools in disease management.

TSHR Gene (rs179247) Polymorphism and Susceptibility to Autoimmune Thyroid Disease: A Systematic Review and Meta-Analysis

BACKGRUOUND

Both Graves' disease (GD) and Hashimoto's thyroiditis (HT) are classified as autoimmune thyroid diseases (AITDs). It has been hypothesized that changes in the thyroid-stimulating hormone receptor (TSHR) gene may contribute to the development of these conditions. This study aimed to analyze the correlation between the TSHR rs179247 gene polymorphism and susceptibility to AITD.

METHODS

We conducted a thorough search of the Google Scholar, Scopus, Medline, and Cochrane Library databases up until March 2, 2024, utilizing a combination of relevant keywords. This review examines data on the association between TSHR rs179247 and susceptibility to AITD. Random-effect models were employed to assess the odds ratio (OR), and the findings are presented along with their respective 95% confidence intervals (CIs).

RESULTS

The meta-analysis included 12 studies. All genetic models of the TSHR rs179247 gene polymorphism were associated with an increased risk of developing GD. Specifically, the associations were observed in the dominant model (OR, 1.65; P<0.00001), recessive model (OR, 1.65; P<0.00001), as well as for the AA genotype (OR, 2.09; P<0.00001), AG genotype (OR, 1.39; P<0.00001), and A allele (OR, 1.44; P<0.00001). Further regression analysis revealed that these associations were consistent regardless of the country of origin, sample size, age, and sex distribution. However, no association was found between TSHR rs179247 and the risk of HT across all genetic models.

CONCLUSION

This study suggests that the TSHR rs179247 gene polymorphism is associated with an increased risk of GD, but not with HT, and may therefore serve as a potential biomarker.

Identification of potential immunotherapeutic targets and prognostic biomarkers in Graves' disease using weighted gene co-expression network analysis

Graves' disease (GD) is an autoimmune disorder characterized by hyperthyroidism resulting from autoantibody-induced stimulation of the thyroid gland. Despite recent advancements in understanding GD's pathogenesis, the molecular processes driving disease progression and treatment response remain poorly understood. In this study, we aimed to identify crucial immunogenic factors associated with GD prognosis and immunotherapeutic response. To achieve this, we implemented a comprehensive screening strategy that combined computational immunogenicity-potential scoring with multi-parametric cluster analysis to assess the immunomodulatory genes in GD-related subtypes involving stromal and immune cells. Utilizing weighted gene co-expression network analysis (WGCNA), we identified co-expressed gene modules linked to cellular senescence and immune infiltration in CD4+ and CD8+ GD samples. Additionally, gene set enrichment analysis enabled the identification of hallmark pathways distinguishing high- and low-immune subtypes. Our WGCNA analysis revealed 21 gene co-expression modules comprising 1,541 genes associated with immune infiltration components in various stages of GD, including T cells, M1 and M2 macrophages, NK cells, and Tregs. These genes primarily participated in T cell proliferation through purinergic signaling pathways, particularly neuroactive ligand-receptor interactions, and DNA binding transcription factor activity. Three genes, namely PRSS1, HCRTR1, and P2RY4, exhibited robustness in GD patients across multiple stages and were involved in immune cell infiltration during the late stage of GD (p < 0.05). Importantly, HCRTR1 and P2RY4 emerged as potential prognostic signatures for predicting overall survival in high-immunocore GD patients (p < 0.05). Overall, our study provides novel insights into the molecular mechanisms driving GD progression and highlights potential key immunogens for further investigation. These findings underscore the significance of immune infiltration-related cellular senescence in GD therapy and present promising targets for the development of new immunotherapeutic strategies.

Molecular Mechanisms in Autoimmune Thyroid Disease

The most common cause of acquired thyroid dysfunction is autoimmune thyroid disease, which is an organ-specific autoimmune disease with two presentation phenotypes: hyperthyroidism (Graves-Basedow disease) and hypothyroidism (Hashimoto's thyroiditis). Hashimoto's thyroiditis is distinguished by the presence of autoantibodies against thyroid peroxidase and thyroglobulin. Meanwhile, autoantibodies against the TSH receptor have been found in Graves-Basedow disease. Numerous susceptibility genes, as well as epigenetic and environmental factors, contribute to the pathogenesis of both diseases. This review summarizes the most common genetic, epigenetic, and environmental mechanisms involved in autoimmune thyroid disease.

Genotype-phenotype correlations in Graves' disease

Graves' disease (GD) is a heterogeneous autoimmune disease affecting with varying degrees of severity the thyroid gland, orbital tissues and skin. The pathogenesis of GD involves a complex interplay between multiple genetic, environmental and endogenous factors. Although the genetic predisposition to GD is well established, the significance of genotype-phenotype correlations and the role of epigenetic modifications in the disease pathogenesis remains largely unknown. In this review, we provide an up-to-date overview of genotype-phenotype correlations and summarize possible clinical implications of genetic and epigenetic markers in GD patients. We will specifically discuss the association of genetic markers and epigenetic modifications with age of GD onset, severity of Graves' hyperthyroidism and the development of clinically evident Graves' orbitopathy.

Mutation of Hashimoto’s Thyroiditis and Papillary Thyroid Carcinoma Related Genes and the Screening of Candidate Genes

Clinical studies have shown similarities in the genetic background and biological functional characteristics between Hashimoto’s thyroiditis (HT) and papillary thyroid carcinoma (PTC), and that HT may increase risks of PTC. Here, we set to determine the gene expression specificity of HT and PTC by screening related genes or co-expressed genes and exploring their genetic correlation. Referencing the Oncomine database, HT-related genes were discovered to be expressed in many different types of thyroid cancer, such as TSHR that is highly expressed in thyroid cancer. An in-depth genetic analysis and verification of 35 cancer and paracancerous tissue pairs from patients with thyroid cancer, and 35 tissues and blood cells pairs from patients with Hashimoto’s thyroiditis was conducted. Gene chip technology research showed that TSHR, BACH2, FOXE1, RNASET2, CTLA4, PTPN22, IL2RA and other HT-related genes were all expressed in PTC, in which TSHR was significantly over-expressed in PTC patients sensitive to radioactive iodine therapy, while BACH2 was significantly under-expressed in these patients. The biologically significant candidate Tag SNP highlighted from HT-related genes was screened by the high-throughput detection method. Somatic mutations in patients with HT and PTC were detected by target region capture technique, and 75 mutations were found in patients with HT and PTC. The upstream regulatory factors of the different genes shared by HT and PTC were analyzed based on Ingenuity Pathway Analysis (IPA), and it was found that HIF-1α and PD-L1 could be used as important upstream regulatory signal molecules. These results provide a basis for screening key diagnostic genes of PTC by highlighting the relationship between some HT-related genes and their polymorphisms in the pathogenesis of PTC.

The risk factors for Graves' ophthalmopathy

PURPOSE

This review aimed to provide an overview of current research into the risk factors for Graves' ophthalmopathy (GO).

METHODS

To find information about the risk factors for GO, the research database PubMed was searched and relevant articles were obtained to extract information about risk factors.

RESULTS

Smoking has been widely accepted as an important risk factor and cigarette smoking cessation has been shown to improve the outcome and decrease the onset of GO. Radioactive iodine on the thyroid may induce hyperthyroidism and increase the occurrence of GO. Selenium deficiency is a risk factor for GO and the supplementation of selenium has been an adjuvant therapy. Decreasing stressful life events (SLE) may help improve GO. Imbalance in intestinal flora is essential to GO, with Yersinia enterocolitica and Escherichia coli both increased in the digestive tract of the individual with GO. In addition, controlling serum cholesterol may help improve GO since adipogenesis is an important pathological change in its pathogenesis. Considering the correlation between Graves' disease and GO, maintaining normal thyroid function hormone level is the first-line therapeutic strategy to prevent progression of GO. An increase in antibodies such as TSHR and IGF-1R is the main predictor of GO. Besides, gender and gene polymorphism are also risk factors towards GO.

CONCLUSIONS

Risk factors for GO arise from five sources: physical and chemical environment, social-psychological environment, biological environment, the human organism, and genetic codes. Risk factors within these categories may interact with each other and their mechanisms in promoting the development of GO are complex. Research into risk factors for GO may promote emerging fields related to GO such as control of autoantibodies and intestinal microbiota.

Significant association of LXRβ (NR1H2) polymorphisms (rs28514894, rs2303044) with type 2 diabetes mellitus and laboratory characteristics

Purpose

To investigate if single-nucleotide polymorphisms (SNPs) in the NR1H2 gene encoding LXRβ contribute to the development of type-2 diabetes mellitus (T2DM) and whether genotypes of two NR1H2 polymorphisms, rs28514894 and rs2303044, are associated with laboratory characteristics of T2DM patients.

Method

A total of 900 subjects (450 T2DM cases and 450 healthy subjects) of Iranian ancestry were genotyped for NR1H2 polymorphisms via ARMS-PCR and PCR-RFLP techniques.

Result

Our findings showed a significant correlation between both polymorphisms and increased risk of T2DM. The haplotype analysis showed an association between the C A haplotype with enhanced risk of T2DM. In T2DM patients, the mean level of HbA1C and BUN significantly differed among carriers of CC and TT genotypes of the rs28514894 polymorphism (P = 0.05 and P < 0.0001, respectively); while in the control group, no significant difference was noticed between subjects with these genotypes. The mean BUN levels also significantly differed among carriers of TC and TT genotypes of this variant in T2DM patients (P = 0.01) and controls (P = 0.04). As for rs2303044 polymorphism, only the mean BUN level significantly differed between GA and GG carriers in T2DM patients (P = 0.006). Compared with CT and TT genotypes, the CC genotype of rs28514894 polymorphism was more frequent in overweight T2DM patients ( 25 < body mass index < 30).

Conclusions

The present research provided the first documents of the correlation of NR1H2 rs28514894 and rs2303044 polymorphisms with susceptibility to T2DM. Replicated case-control studies on larger populations are needed to validate these findings.

Polymorphisms of the genes CTLA4, PTPN22, CD40, and PPARG and their roles in Graves' disease: susceptibility and clinical features

PURPOSE

CTLA4, PTPN22, and CD40 are immune-regulatory genes strongly associated with GD, as well as PPARG, but their clinical significance in different populations is still uncertain.

METHODS

We genotyped 282 Brazilian GD patients (234 women and 48 men, 39.80 ± 11.69 years old), including 144 patients with GO, and 308 healthy control individuals (246 women and 62 men, 36.86 ± 12.95 years old).

RESULTS

A multivariate analysis demonstrated that the inheritance of the GG genotype rs3087243 of CTLA4 (OR = 2.593; 95% CI = 1.630-4.123; p < 0.0001) and the CC genotype of rs3789607 of PTPN22 (OR = 2.668; 95% CI = 1.399-5.086; p = 0.0029) consisted in factors independent of the susceptibility to GD. The inheritance of polymorphic genotypes of rs5742909 of CTLA4 was associated with older age at the time of diagnosis (42.90 ± 10.83 versus 38.84 ± 11.81 years old; p = 0.0105), with higher TRAb levels (148.17 ± 188.90 U/L versus 112.14 ± 208.54 U/L; p = 0.0229) and the need for higher therapeutic doses of radioiodine (64.23 ± 17.16 versus 50.22 ± 16.86; p = 0.0237). The inheritance of the CC genotype of rs1883832 CD40 gene was more frequent among women (69.65%) than men (52.00%; p = 0.0186). The polymorphic genotype of PPARG gene (rs1801282) was associated with TPOAb positivity (p = 0.0391), and the GG genotype of rs2476601 of PTPN22 gene was associated with positivity for both TgAb (p = 0.0360) and TPOAb (p < 0.0001). Both polymorphic genotypes rs2476601 and rs3789607 of the PTPN22 gene were more frequent among nonsmoking patients (p = 0.0102 and p = 0.0124, respectively).

CONCLUSIONS

Our data confirm the important role of CTLA4 polymorphisms in GD susceptibility; demonstrate the role of PTPN22 polymorphisms in patients' clinical features; and suggest these genes may influence the severity of the disease.

Correlation of TSHR and CTLA-4 Single Nucleotide Polymorphisms with Graves Disease

This study was designed to explore the association between Graves disease (GD) and thyroid-stimulating hormone receptor (TSHR) and cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) single nucleotide polymorphisms (SNPs). We studied a total of 1217 subjects from a Han population in northern Anhui province in China. Six SNPs within TSHR (rs179247, rs12101261, rs2284722, rs4903964, rs2300525, and rs17111394) and four SNPs within CTLA-4 (rs10197319, rs231726, rs231804, and rs1024161) were genotyped via a Taqman probe technique using a Fluidigm EP1 platform. The TSHR alleles rs179247-G, rs12101261-C, and rs4903964-G were negatively correlated with GD, whereas the rs2284722-A and rs17111394-C alleles were positively correlated with GD. Analyzing TSHR SNPs at rs179247, rs2284722, rs12101261, and rs4903964 yielded 8 different haplotypes. There were positive correlations between GD risk and the haplotypes AGTA and AATA (OR = 1.27, 95%CI = 1.07-1.50, P = 0.005; OR = 1.45, 95%CI = 1.21-1.75, P < 0.001, respectively). There were negative correlations between GD risk and the haplotype GGCG (OR = 0.56, 95%CI = 0.46-0.67, P < 0.001). With respect to haplotypes based on SNPs at the TSHR rs2300525 and rs17111394 loci, the CC haplotype was positively correlated with GD risk (OR = 1.32, 95%CI = 1.08-1.60, P = 0.006). Analyzing CTLA-4 SNPs at rs231804, rs1024161, and rs231726 yielded four haplotypes, of which AAA was positively correlated with GD risk (OR = 1.21, 95%CI = 1.02-1.43, P = 0.029). Polymorphisms at rs179247, rs12101261, rs2284722, rs4903964, and rs17111394 were associated with GD susceptibility. Haplotypes of both TSHR and CTLA-4 were additionally related to GD risk.

Analysis of chosen polymorphisms rs2476601 a/G - PTPN22, rs1990760 C/T - IFIH1, rs179247 a/G - TSHR in pathogenesis of autoimmune thyroid diseases in children

BACKGROUND

Autoimmune thyroid diseases are multifactorial diseases with a genetic susceptibility and environmental factors. A potential role of the protein tyrosine phosphatase non-receptor type 22 (PTPN22) gene, the interferon-induced helicase domain 1 (IFIH1) gene, the thyroid-stimulating hormone receptor (TSHR) gene polymorphisms on autoimmune thyroid diseases (AITDs) in adults has been established unequivocally, but there is still lack of research articles including group of children. Objective and hypotheses: To estimate the association of polymorphisms of PTPN22, IFIH1 and TSH-R genes with the pre-disposition to Graves' disease (GD) and Hashimoto's thyroiditis (HT) in children.

METHODS

The study was performed in 142 patients with GD, 57 with HT and 160 healthy volunteers. The three single-nucleotide polymorphisms (SNPs): rs2476601 - PTPN22, rs1990760 - IFIH1 and rs179247 - TSHR were genotyped by TaqMan SNP genotyping assay using the real-time PCR.

RESULTS

Rs2476601 A alleles were more frequent in patients with GD in comparison to healthy subjects (p = .009 with odds ratio [OR] = 2.13). Rs2476601 A alleles were more frequent in patients with HT in comparison to healthy subjects (p = .008, OR = 2.48). Rs1990760 T alleles were more frequent in male patients with GD in comparison to healthy males (p = .003, OR = 3.00). In case of HT patients, rs1990760 T alleles were also more frequent in males compared to healthy subjects (p = .086, OR =2.47). Rs179247 A alleles were more frequent in patients with GD in comparison to healthy subjects (p = 0.039, OR = 1.51).

CONCLUSIONS

Rs2476601 A/G, Rs1990760 C/T and Rs179247 A/G polymorphisms could contribute to the development of AITDs in children. The main risk factor for rs2476601 and rs179247 is allele A. In case of rs1990760, the main risk factor is allele T.

The Emerging Role of Epigenetics in Autoimmune Thyroid Diseases

Autoimmune thyroid diseases (AITD) are a group of both B cell- and T cell-mediated organ-specific autoimmune diseases. Graves’ disease and Hashimoto thyroiditis are the two main clinical presentations of AITD. Both genetic and environmental factors have important roles in the development of AITD. Epigenetics have been considered to exert key roles in integrating those genetic and environmental factors, and epigenetic modifications caused by environmental factors may drive genetically susceptibility individuals to develop AITD. Recent studies on the epigenetics of AITD have provided some novel insights into the pathogenesis of AITD. The aim of this review is to provide an overview of recent advances in the epigenetic mechanisms of AITD, such as DNA methylation, histone modifications, and non-coding RNAs. This review highlights the key roles of epigenetics in the pathogenesis of AITD and potential clinical utility. However, the epigenetic roles in AITD are still not fully elucidated, and more researches are needed to provide further deeper insights into the roles of epigenetics in AITD and to uncover new therapeutic targets. Although there are many studies assessing the epigenetic modifications in AITD patients, the clinical utility of epigenetics in AITD remains poorly defined. More studies are needed to identify the underlying epigenetic modifications that can contribute to accurate diagnosis of AITD, adequate choice of treatment approach, and precise prediction of treatment outcomes.

Genetics of Thyroid-Stimulating Hormone Receptor-Relevance for Autoimmune Thyroid Disease

Production of thyroid-stimulating hormone receptor (TSHR) antibodies represents the hallmark of Graves' disease (GD) pathogenesis. Thus, for more than two decades the TSHR gene has been at the center of studies intended to elucidate its contribution to disease pathology. The advent of genome-wide association technology allowed to establish a strong association of the TSHR gene with GD. Subsequent fine-mapping studies narrowed the disease-susceptibility region to a 40 kb sequence in intron 1, where at least five GD-associated SNPs in tight linkage disequilibrium were identified. The current challenge is to understand the functional mechanisms by which these polymorphisms modify physiological processes and trigger disease. The aim of this review is to summarize the current knowledge on the role of the TSHR gene in GD pathogenesis, which has been gained through linkage and association studies, as well as to discuss the emerging mechanisms underlying biological implications of TSHR variants in the development of GD.

Association of polymorphisms of rs179247 and rs12101255 in thyroid stimulating hormone receptor intron 1 with an increased risk of Graves' disease: A meta-analysis

The polymorphisms of thyroid stimulating hormone receptor (TSHR) intron 1 rs179247 and rs12101255 have been found to be associated with Graves' disease (GD) in genetic studies. In the present study, we conducted a meta-analysis to examine this association. Two reviewers systematically searched eligible studies in PubMed, Web of Science, Embase and China Biomedical Literature Database (CBM). A meta-analysis on the association between GD and TSHR intron 1 rs179247 or rs12101255 was performed. The odd ratios (OR) were estimated with 95% confidence interval (CI). Meta package in R was used for the analyses. Seven articles (13 studies) published between 2009 and 2014, involving 5754 GD patients and 5768 controls, were analyzed. The polymorphism of rs179247 was found to be associated with an increased GD risk in the allele analysis (A vs. G: OR=1.40, 95% CI=1.33-1.48) and all genetic models (AA vs. GG: OR=1.94, 95% CI=1.73-2.19; AA+AG vs. GG: OR=1.57, 95% CI=1.41-1.74; AA vs. AG+GG: OR=1.54, 95% CI=1.43-1.66). The site rs12101255 also conferred a risk of GD in the allele analysis (T vs. C: OR=1.50, 95% CI=1.40-1.60) and all genetic models (TT vs. CC: OR=2.22, 95% CI=1.92-2.57; TT+TC vs. CC: OR=1.66, 95% CI=1.50-1.83; TT vs. TC+CC: OR=1.74, 95% CI=1.53-1.98). Analysis of the relationship between rs179247 and Graves' ophthalmopathy (GO) showed no statistically significant correlation (A vs. G: OR=1.02, 95% CI=0.97-1.07). Publication bias was not significant. In conclusion, GD is associated with polymorphisms of TSHR intron 1 rs179247 and rs12101255. There is no association between rs179247 SNPs and GO.

Genetic associations of the thyroid stimulating hormone receptor gene with Graves diseases and Graves ophthalmopathy: A meta-analysis

Graves' disease (GD) is a common thyroid disease, and Graves ophthalmopathy(GO) is the most common extra-thyroidal manifestation of GD. Genetic associations of the thyroid stimulating hormone receptor (TSHR) gene with GD and GO have been studied in different population groups for a long time. We aimed to obtain a more precise estimation of the effects of TSHR single nucleotide polymorphisms (SNPs) on GD/GO using a meta-analysis. Publications were searched on Pub Med and EMBASE up to December 30, 2015. Eight studies involving three SNPs (rs179247, rs12101255, and rs2268458), which included 4790 cases and 5350 controls, met the selection criteria. The pooled odds ratios (OR) and the 95% confidence intervals (CI) were estimated. SNPs rs179247 (dominant model [GG + GA vs. AA]: OR = 0.66, 95%CI: 0.61-0.73, P = 0.000, I(2) = 0%) and rs12101255 (dominant model [TT + TC vs. CC]: OR = 1.67, 95%CI: 1.53-1.83, P = 0.000, I(2) = 0%) were significantly associated with GD in all of the genetic models. TSHR rs12101255 and rs2268458 polymorphisms had no association between GO and GD (GD without GO). The results indicate that rs179247 and rs12101255 are likely to be genetic biomarkers for GD. Further studies with different population groups and larger sample sizes are needed to confirm the genetic associations of the TSHR gene with GD/GO.

Association between TSHR gene polymorphism and the risk of Graves' disease: a meta-analysis

Thyroid stimulating hormone receptor (TSHR) is thought to be a significant candidate for genetic susceptibility to Graves' disease (GD). However, the association between TSHR gene polymorphism and the risk of GD remains controversial. In this study, we investigated the relationship between the two conditions by meta-analysis. We searched all relevant case-control studies in PubMed, Web of Science, CNKI and Wanfang for literature available until May 2015, and chose studies on two single nucleotide polymorphisms (SNPs): rs179247 and rs12101255, within TSHR intron-1. Bias of heterogeneity test among studies was determined by the fixed or random effect pooled measure, and publication bias was examined by modified Begg's and Egger's test. Eight eligible studies with 15 outcomes were involved in this meta-analysis, including 6,976 GD cases and 7,089 controls from China, Japan, Poland, UK and Brazil. Pooled odds ratios (ORs) for allelic comparisons showed that both TSHR rs179247A/G and rs12101255T/C polymorphism had significant association with GD (OR=1.422, 95%CI=1.353–1.495, P<0.001, P_{heterogeneity}=0.448; OR=1.502, 95%CI: 1.410–1.600, P<0.001, P_{heterogeneity}=0.642), and the associations were the same under dominant, recessive and co-dominant models. In subgroup analyses, the conclusions are also consistent with all those in Asian, European and South America subgroups (P<0.001). Our meta-analysis revealed a significant association between TSHR rs179247A/G and rs12101255T/C polymorphism with GD in five different populations from Asia, Europe and South America. Further studies are needed in other ethnic backgrounds to independently confirm our findings.

BRAF-Activated Long Noncoding RNA Modulates Papillary Thyroid Carcinoma Cell Proliferation through Regulating Thyroid Stimulating Hormone Receptor

PURPOSE

The importance of long noncoding RNAs (lncRNAs) in tumorigenesis has recently been demonstrated. However, the role of lncRNAs in development of thyroid cancer remains largely unknown.

MATERIALS AND METHODS

Using quantitative reverse transcription polymerase chain reaction, expression of three lncRNAs, including BRAF-activated long noncoding RNA (BANCR), papillary thyroid cancer susceptibility candidate 3 (PTCSC3), and noncoding RNA associated with mitogen-activated protein kinase pathway and growth arrest (NAMA), was investigated in the current study.

RESULTS

Of the three lncRNAs (BANCR, PTCSC3, and NAMA), expression of BANCR was significantly up-regulated while PTCSC3 and NAMA were significantly down-regulated in papillary thyroid carcinoma (PTC) compared to that in normal tissue. BANCR-knockdown in a PTC-derived cell line (IHH-4) resulted in significant suppression of thyroid stimulating hormone receptor (TSHR). BANCR-knockdown also led to inhibition of cell growth and cell cycle arrest at G0/G1 phase through down-regulation of cyclin D1. In addition, BANCR was enriched by polycomb enhancer of zeste homolog 2 (EZH2), and silencing BANCR led to decreased chromatin recruitment of EZH2, which resulted significantly reduced expression of TSHR.

CONCLUSION

These findings indicate that BANCR may contribute to the tumorigenesis of PTC through regulation of cyclin D1 and TSHR.