ACAP3 negatively regulated by HDAC2 inhibits the malignant development of papillary thyroid carcinoma cells.

ArfGAP with coiled-coil, ankyrin repeat and PH domains 3 (ACAP3) level has been confirmed to be downregulated in papillary thyroid carcinoma (PTC). Histone deacetylase inhibitors (HDACIs) have therapeutic effects on PTC. Accordingly, this study probed into the potential relation of histone deacetylase 2 (HDAC2) and ACAP3 in PTC. Expressions of ACAP3 and HDAC2 in PTC were investigated by quantitative real-time polymerase chain reaction (qRT-PCR). The relationship between HDAC2 and ACAP3 was predicted by Pearson analysis. Cell functional assays (cell counting kit-8, transwell, wound healing and flow cytometry assays) and rescue assay were carried out to determine the effects of HDAC2/ACAP3 axis on biological behaviors of PTC cells. Expressions of apoptosis-, epithelial-mesenchymal transition-, Protein Kinase B (AKT)-, and P53-related proteins were measured by Western blot. ACAP3 level was downregulated in PTC tissues and cells. ACAP3 overexpression (oe-ACAP3) suppressed viability, proliferation, migration and invasion of PTC cells, facilitated apoptosis, downregulated the expressions of Protein Kinase B (Bcl-2) and N-cadherin, upregulated the expressions of Bcl-2 associated protein X (Bax) and E-cadherin, diminished the p-AKT/AKT ratio and elevated the p-p53/p53 ratio; however, ACAP3 silencing or HDAC2 overexpression (oe-HDAC2) did the opposite. HDAC2 negatively correlated with ACAP3. The tumor-suppressing effect of oe-ACAP3 in PTC was reversed by oe-HDAC2. Collectively, ACAP3 negatively regulated by HDAC2 suppresses the proliferation and metastasis while facilitating apoptosis of PTC cells.

Plasma miRNA-146b-3p, -222-3p, -221-5p, -21a-3p Expression Levels and TSHR Methylation: Diagnostic Potential and Association with Clinical and Pathological Features in Papillary Thyroid Cancer.

This study aimed to investigate the expression of microRNAs (miRNAs) -146b-3p, -221-5p, -222-3p, and -21a-3p and the methylation pattern of the thyroid-stimulating hormone receptor (TSHR) gene in blood plasma samples from papillary thyroid cancer (PTC) patients before and after thyroidectomy compared to healthy controls (HCs). This study included 103 participants, 46 PTC patients and 57 HCs, matched for gender and age. Significantly higher preoperative expression levels of miRNAs and TSHR methylation were determined in the PTC patients compared to HCs. Post-surgery, there was a notable decrease in these biomarkers. Elevated TSHR methylation was linked to larger tumor sizes and lymphovascular invasion, while increased miRNA-222-3p levels correlated with multifocality. Receiver operating characteristic (ROC) analysis showed AUCs below 0.8 for all candidate biomarkers. However, significant changes in the expression of all analyzed miRNAs and TSHR methylation levels indicate their potential to differentiate PTC patients from healthy individuals. These findings suggest that miRNAs and TSHR methylation levels may serve as candidate biomarkers for early diagnosis and monitoring of PTC, with the potential to distinguish PTC patients from healthy individuals. Further research is needed to validate these biomarkers for clinical application.

Higher microRNA-221 and lower microRNA-451 expression are associated with poor prognosis in patients with thyroid papillary carcinoma.

BACKGROUND: To analyze the relationship between serum microRNA-221 and microRNA-451 expression and the pathological features and prognosis of patients with thyroid papillary carcinoma. METHODS: Cross-sectional study that included 120 patients with papillary thyroid cancer treated at the hospital and 120 healthy volunteers selected as the control group who underwent physical examination. The relative expression levels of microRNA-221 and microRNA-451 were compared between the thyroid papillary carcinoma group (prior to treatment) and the control group. Additionally, microRNA-221 and microRNA-451 expression levels were analyzed in patients with papillary thyroid carcinoma across different pathological characteristics. RESULTS: Serum microRNA-221 relative levels were significantly higher (p<0.001) in the papillary carcinoma group compared to the control group, while microRNA-451 levels were higher in the control group (p<0.001). In the papillary carcinoma group, microRNA-221 expression was significantly higher in patients with extracapsular invasion (p<0.001), lymphatic metastasis (p=0.003), and poor prognosis (p<0.001). Conversely, microRNA-451 expression was significantly lower (p<0.001) in patients with extracapsular invasion, lymphatic metastasis and poor prognosis. In the multivariate logistic regression analysis, morphological features suggestive of an aggressive clinical behavior (extracapsular invasion and lymphatic metastasis) were related to high expression of microRNA-221 and low expression of microRNA-451 in patients with thyroid papillary carcinoma (p<0.001). CONCLUSIONS: Serum microRNA-221 and microRNA-451 expression levels are significantly higher and lower, respectively, in patients with papillary thyroid carcinoma, particularly in patients with morphological features suggestive of an aggressive clinical behavior (extracapsular invasion and lymphatic metastasis) and, therefore, of a poor prognosis.

Biomarkers related to m6A and succinic acid metabolism in papillary thyroid carcinoma.

BACKGROUND: Studies have shown that m6A modification is related to the occurrence and development of papillary thyroid carcinoma (PTC). The disorder of succinic acid metabolism is associated with the occurrence and development of various tumors. However, there are few studies based on m6A and succinate metabolism-related genes (SMRGs) in PTC. METHODS: The TCGA-Thyroid carcinoma (THCA), GSE33630, 1159 SMRGs, and 23 m6A regulatory factors were collected from the online databases. Subsequently, the differentially expressed genes (DEGs) were selected between PTC (Tumor) and Normal samples. The overlapping genes among the DEGs, m6A, and SMRGs were applied to screen the biomarkers. Using the 3 machine-learning algorithms, the biomarkers were determined based on the overlapping genes. Next, the biomarkers were evaluated by the ROC curve and expression analysis in TCGA-THCA and GSE33630. Then, the overall survival (OS) differences were compared between the high-and low-expression biomarkers. Finally, immune infiltration analysis, molecular regulatory network, and drug prediction were performed based on the biomarkers. RESULTS: In TCGA-THCA, there were 2800 DEGs between and Normal samples, and then 7 overlapping genes were obtained. Importantly, ADK, TNFRSF10B, CYP7B1, FGFR2, and CPQ were determined as biomarkers with excellent diagnostic efficiency (AUC > 0.7). In PTC samples, ADK and TNFRSF10B were high-expressed while CYP7B1, FGFR2, and CPQ were low-expressed. Especially, the high-expression groups of ADK had a better prognosis, while the high-expression groups of CYP7B1, FGFR2, and CPQ had a worse prognosis. Afterward, immune infiltration analysis found that 16 immune cells had infiltration differences between the Tumor and Normal samples. Finally, transcription factor SP1 could regulate CYP7B1 and TNFRSF10B. Moreover, Navitoclax was a potential drug for PTC patients. CONCLUSION: Overall, we described 5 biomarkers associated with adverse prognosis of PTC, including ADK, TNFRSF10B, CYP7B1, FGFR2, and CPQ. All these biomarkers were involved in succinate metabolism and m6A modification of RNA. This set of biomarkers should be explored further for their diagnostic value in PTC. Investigations into the mechanistic role of alteration of succinate metabolism and m6A modification of RNA pathways in the pathophysiology of PTC are warranted.

Gene Expression Profiles of AHNAK2, DCSTAMP, FN1, and TERT Correlate With Mutational Status and Recurrence in Papillary Thyroid Carcinoma.

Papillary thyroid carcinoma (PTC), the most common malignancy of follicular cell derivation, is generally associated with good prognosis. Nevertheless, it is important to identify patients with aggressive PTCs and unfavorable outcome. Molecular markers such as BRAFV600E mutation and TERT promoter mutations have been proposed for risk stratification. While TERT promoter mutations have been frequently associated with aggressive PTCs, the association of BRAFV600E mutation with increased recurrence and mortality is less clear and has been controversially discussed. The aim of the present study was to analyze whether differentially expressed genes can predict BRAFV600E mutations as well as TERT promoter mutations in PTCs. RNA sequencing identified a large number of differentially expressed genes between BRAFV600E and BRAFwildtype PTCs. Of those, AHNAK2, DCSTAMP, and FN1 could be confirmed in a larger cohort (n = 91) to be significantly upregulated in BRAFV600E mutant PTCs using quantitative RT-PCR. Moreover, individual PTC expression values of DCSTAMP and FN1 were able to predict the BRAFV600E mutation status with high sensitivity and specificity. The expression of TERT was detected in all PTCs harboring TERT promoter mutations and in 19% of PTCs without TERT promoter mutations. Tumors with both TERT expression and TERT promoter mutations were particularly associated with aggressive clinicopathological features and a shorter recurrence-free survival. Altogether, it will be interesting to explore the biological function of AHNAK2, DCSTAMP, and FN1 in PTC in more detail. The analysis of their expression patterns could allow the characterization of PTC subtypes and thus enabling a more individualized surgical and medical treatment.

Mitochondrial DNA copy number and risk of papillary thyroid carcinoma.

BACKGROUND: Mitochondrial DNA (mtDNA) copy number is associated with tumor activity and carcinogenesis. This study was undertaken to investigate mtDNA copy number in papillary thyroid cancer (PTC) tissues and to evaluate the risk of PTC development. The clinicopathological features of patients and mtDNA copy number were correlated. The value of mtDNA copy number was evaluated as a biomarker for PTC. METHOD: DNA was extracted from 105 PTC tissues and 67 control thyroid tissues, and mtDNA copy number mtDNA oxidative damage were determined using qPCR techniques. RESULTS: Overall, the relative mtDNA copy number was significantly higher in PTC patients (p < 0.001). The risk of developing PTC increased significantly across the tertiles of mtDNA copy number (p trend < 0.001). The higher the mtDNA copy number tertile, the greater the risk of developing PTC. Patients with follicular variants had an odds ratio of 2.09 (95% CI: 1.78-2.44) compared to those with classical variants (p < 0.001). The level of mtDNA oxidative damage in PTC was significantly elevated compared to controls (p < 0.001). The ROC analysis of mtDNA copy number indicated an area under the curve (AUC) of 77.7% (95% CI: 0.71 to 0.85, p < 0.001) for the ability of mtDNA copy number z-scores in differentiate between PTC and controls. CONCLUSION: Our results indicated that the augmentation of mtDNA content plays a significant role during the initiation of thyroid cancer, and it might represent a potential biomarker for predicting the risk of PTC.

The role of immune cells and immune related genes in the tumor microenvironment of papillary thyroid cancer and their significance for immunotherapy.

Papillary thyroid carcinoma (PTC) is the most common pathological type of thyroid cancer (THCA) and shows a better prognosis than other types. However, further research is needed to determine the risk of PTC. We herein used the CIBERSORT algorithm to analyze the gene-expression profile obtained from TCGA, estimated the infiltration ratio of 22 immune cell types in tumor tissues and normal tissues, analyzed the differential expression of immune-related genes, and identified immune cells and immune-related genes related to clinical progress and prognosis. We uncovered 12 immune cell types and nine immune-related genes that were closely correlated with TNM staging, and two immune cell types (activated NK cells and γδT cells) and one immune-related gene (CD40LG) that were associated with prognosis. After evaluation, four immune cell types could be used to determine low-risk PTC, with six immune cell types and six immune-related genes closely associated with high-risk PTC. The type and quantity of infiltrating immune cells in the microenvironment of PTC, as well as immune-related genes, appear to be closely related to tumor progression and can therefore be used as important indicators for the evaluation of patient prognosis. We posit that the study of immune cells and immune-related genes in the tumor microenvironment will facilitate the determination of low-risk PTC more accurately, and that this will greatly promote the development of high-risk PTC immunotherapy.

METTL3 regulates thyroid cancer differentiation and chemosensitivity by modulating PAX8.

Background: Thyroid cancer (TC) is a common endocrine cancer with a favourable prognosis. However, poor patient prognosis due to TC dedifferentiation is becoming an urgent challenge. Recently, methyltransferase-like 3 (METTL3)-mediated N6 -methyladenosine (m6A) modification has been demonstrated to play an important role in the occurrence and progression of various cancers and a tumour suppressor role in TC. However, the mechanism of METTL3 in TC remains unclear. Methods: The correlation between METTL3 and prognosis in TC patients was evaluated by immunohistochemistry. Mettl3fl/flBrafV600ETPO-cre TC mouse models and RNA-seq were used to investigate the underlying molecular mechanism, which was further validated by in vitro experiments. The target gene of METTL3 was identified, and the complete m6A modification process was described. The phenomenon of low expression of METTL3 in TC was explained by identifying miRNAs that regulate METTL3. Results: We observed that METTL3 expression was negatively associated with tumour progression and poor prognosis in TC. Mechanistically, silencing METTL3 promoted the progression and dedifferentiation of papillary thyroid carcinoma (PTC) both in vivo and in vitro. Moreover, overexpressing METTL3 promoted the sensitivity of PTC and anaplastic thyroid cancer (ATC) cells to chemotherapeutic drugs and iodine-131 (131I) administration. Overall, the METTL3/PAX8/YTHDC1 axis has been revealed to play a pivotal role in repressing tumour occurrence, and is antagonized by miR-493-5p.

Genetic and Epigenetic Association of FOXP3 with Papillary Thyroid Cancer Predisposition.

Papillary thyroid cancer (PTC) is the most common type of thyroid malignancy with an increased female incidence ratio. The specific traits of X chromosome inheritance may be implicated in gender differences of PTC predisposition. The aim of this study was to investigate the association of two X-linked genes, Forkhead Box P3 (FOXP3) and Protein Phosphatase 1 Regulatory Subunit 3F (PPP1R3F), with PTC predisposition and gender disparity. One hundred thirty-six patients with PTC and an equal number of matched healthy volunteers were enrolled in the study. Genotyping for rs3761548 (FOXP3) and rs5953283 (PPP1R3F) was performed using polymerase chain reaction-restriction fragment length polymorphism assay (PCR-RFLP). The methylation status of FOXP3 was assessed using the combined bisulfite restriction analysis (COBRA) method. The SPSS software was used for statistical analyses. Gender stratification analysis revealed that the CA and AA genotypes and the A allele of FOXP3 rs3761548 variant are associated with PTC predisposition only in females. Moreover, different methylation status was observed up to the promoter locus of FOXP3 between PTC female patients, carrying the CA and CC genotype, and controls. Both revealed associations may explain the higher PTC incidence in females through reducing FOXP3 expression as reported in immune related blood cells.

Identification of mechanism of the oncogenic role of FGFR1 in papillary thyroid carcinoma.

Papillary thyroid carcinoma (PTC) is the most prevalent malignancy of the thyroid. Fibroblast growth factor receptor 1 (FGFR1) is highly expressed in PTC and works as an oncogenic protein in this disease. In this report, we wanted to uncover a new mechanism that drives overexpression of FGFR1 in PTC. Analysis of FGFR1 expression in clinical specimens and PTC cells revealed that FGFR1 expression was enhanced in PTC. Using siRNA/shRNA silencing experiments, we found that FGFR1 downregulation impeded PTC cell growth, invasion, and migration and promoted apoptosis in vitro, as well as suppressed tumor growth in vivo. Bioinformatic analyses predicted the potential USP7-FGFR1 interplay and the potential binding between YY1 and the FGFR1 promoter. The mechanism study found that USP7 stabilized FGFR1 protein via deubiquitination, and YY1 could promote the transcription of FGFR1. Our rescue experiments showed that FGFR1 re-expression had a counteracting effect on USP7 downregulation-imposed in vitro alterations of cell functions and in vivo suppression of xenograft growth. In conclusion, our study identifies the deubiquitinating enzyme USP7 and the oncogenic transcription factor YY1 as potent inducers of FGFR1 overexpression. Designing inhibitors targeting FGFR1 or its upstream inducers USP7 and YY1 may be foreseen as a promising strategy to control PTC development.

CXCL5 expression is associated with active signals of macrophages in the microenvironment of papillary thyroid carcinoma.

BACKGROUND: C-X-C motif chemokine ligand 5 (CXCL5) is a chemokine molecule that is secreted by immune cells in attracting granulocytes. Studies showed that CXCL5 was related to the progression of papillary thyroid carcinoma (PTC) tumor cells. However, the in vivo effects of CXCL5 on PTC tumor cells and their microenvironment have not been elucidated. The present study aimed to investigate the biological effects of CXCL5 on tumor cells, microenvironment, and clinical progression of PTC. MATERIALS AND METHODS: The PTC patients from The Human Cancer Genome Atlas (TCGA) - thyroid carcinoma (THCA) were retrieved. There were a total of 500 patients who met the criteria of our study. Differential expression (DEA) and pathway analyses were used to explore the biological effects of CXCL5 gene expression. RESULTS: In DEA, we found that CXCL5 was mostly associated with PBPP, SLC11A1, and MRC1 (adjusted p<0.001). Samples with CXCL5 FPKM≥1 were related to a different immune profile (p<0.001). In pathway analyses, samples with higher CXCL5 expression possessed higher activities of RAS-RAF, NF-kB, PRC2, IL2, IL5, and Wnt pathways (adjusted p<0.001). In microenvironment analysis, CXCL5 was highly correlated with the activity of macrophage (Rho=0.76; adjusted p<0.001). Clinically, high level of CXCL5 expression was an indicator of tumor stages (p<0.001), nodal metastasis (AUC=0.68), and prognosis (p=0.001). CONCLUSION: CXCL5 was a significant biomarker of PTC. CXCL5 was highly associated with tumor immunology and microenvironment. Samples with higher CXCL5 expression had more advanced disease status and worse prognosis. CXCL5 target therapy is potentially helpful in advanced PTC.

[circ_BACH2 affects the malignant biological behavior of papillary thyroid cancer by regulating miR-370-3p].

Objective: To investigate the influence of circ_BACH2 on the malignant biological behavior of papillary thyroid cancer and its molecular mechanism. Methods: Cancer tissues and paracancer tissues of 51 patients with papillary thyroid carcinoma from the Fourth Central Hospital of Tianjin between 2017 and 2019 were collected. Reverse transcription-quantitative real-time polymerase chain reaction (RT-qPCR) was used to detect the expressions of circ_BACH2, miR-370-3p and G protein coupled receptor kinase interacting factor 1 (GIT1) mRNA in tissues and cells; flow cytometry to detect cell apoptosis and cell cycle; plate clone formation experiment to detect the number of cell clones; cell counting kit 8 (CCK-8) to detect cell proliferation; Transwell array to detect cell migration and invasion; western blot to detect protein expressions; dual luciferase report experiment to detect the targeting relationship between circ_BACH2, miR-370-3p and GIT1; the nude mouse tumor formation experiment to detect the effect of circ_BACH2 on tumors in mice. Results: Compared with adjacent tissues, the expressions of circ_BACH2 and GIT1 in papillary thyroid cancer tissues was increased, while the expression of miR-370-3p was decreased. Compared with Nthy-ori3-1 cells, the expressions of circ_BACH2 in papillary thyroid cancer cells TPC-1 and SW579 were increased, the mRNA and protein levels of GIT1 were increased, miR-370-3p expression was decreased. The expression level of GIT1 mRNA was negatively correlated with that of miR-370-3p (r=-0.634), and the expression level of circ_BACH2 was positively correlated with that of GIT1 (r=0.635). The expression level of circ_BACH2 was negatively correlated with that of miR-370-3p (r=-0.394, P＜0.05). Circ_BACH2 and miR-370-3p has a binding site at the 3' UTR of GIT1. After knocking down circ_BACH2, the proportion of G0/G1 cells in papillary thyroid cancer cells TPC-1 and SW579 was increased, the proportion of S-phase cells was decreased and the proportion of G2/M-phase cells did not change significantly. The cell absorbance value was lower than that in si-NC group. The number of cell clone formation was decreased (43±5 vs 100±6, 54±8 vs 100±9); the cell apoptosis rate was increased [(19.60±2.40)% vs (4.30±0.20)%, (18.10±2.10)% vs (5.10±0.23)%]; cell migration number was decreased (61±7 vs 134±15, 58±6 vs 112±11), the invasion number was also decreased (45±6 vs 113±11, 47±4 vs 92±9); the expressions of Snail and Twist1 were decreased, and the expression of E-cadherin was increased (P＜0.000). Inhibition of miR-370-3p expression reversed the effect of circ_BACH2 knockdown on proliferation, migration, invasion and apoptosis of thyroid papillary cancer cells. Overexpression of GIT1 reversed the effects of overexpression of miR-370-3p on proliferation, migration, invasion and apoptosis of thyroid papillary cancer cells. Mice injected with TPC-1 cells stably transfected with sh-circ_BACH2 showed a reduction in tumor volume [(535±91) mm3 vs (857±114) mm3] after 35 days of culture; tumor weight was decreased [(0.62±0.13) mg vs (1.06±0.15) mg, P＜0.05]; the expressions of circ_BACH2 and GIT1 were decreased, and the expression of miR-370-3p was increased in nude mouse tumor tissue. Conclusion: Silencing circ_BACH2 may inhibit the proliferation, migration and invasion of papillary thyroid cancer cells in vitro, promote cell apoptosis, and inhibit tumor growth in vivo through targeted regulation of miR-370-3p/GIT1.

Case report: An adolescent female with anosmic hypogonadotropic hypogonadism, intellectual disability, and papillary thyroid carcinoma: heterozygous deletion of TCF12.

Background: Isolated hypogonadotropic hypogonadism is a heterogeneous clinical entity. There is a growing list of molecular defects that are associated with hypogonadotropic hypogonadism (HH). TCF12, a recently identified molecular defect, causes craniosynostosis and is suggested to be used as a biomarker for prognosis in various cancer types. Recently, TCF12 variants were shown in a cohort with HH. Case presentation: A 15.3 years old female patient was referred to the endocrinology clinic for obesity. She had been gaining weight from mid-childhood. She had her first epileptic seizure at the age of 15.1 years and mildly elevated thyroid autoantibodies were detected during evaluation for etiology of seizures. She had not experienced menarche yet. She was operated for left strabismus at the age of 7 years. School performance was poor and she was receiving special education. Tanner stage of breast was 1 and pubic hair was 3. The endocrine workup revealed hypogonadotropic hypogonadism. Also, the Sniffin' Sticks test detected anosmia. Thyroid ultrasonography was performed due to the mildly elevated thyroid autoantibodies, and thyroid nodules with punctate calcifications were detected. Total thyroidectomy and central lymph node dissection were performed regarding the cytological findings of the nodules and multicentric papillary thyroid carcinoma with no lymph node metastasis was detected on pathology specimens. Regarding the phenotypic features of the patients, whole exome sequencing was performed and heterozygous deletion of exon 1 and exon 6-8 in TCF12 was detected. Conclusion: Haploinsufficiency of TCF12 causes anosmic HH. Probably due to the incomplete penetrance and variable expressivity of the disease, patients could display variable phenotypic features such as intellectual disability, developmental delay, and craniosynostosis. Further description of new cases with TCF12 variations could enhance our understanding of craniosynostosis and its potential link to Kallmann syndrome associated with this gene.

Proteomics profile in encapsulated follicular patterned thyroid neoplasms.

Diagnosing encapsulated follicular-patterned thyroid tumors like Invasive Encapsulated Follicular Variant of Papillary Thyroid Carcinoma (IEFVPTC), Non-invasive Follicular Thyroid Neoplasm with Papillary-like Nuclear Features (NIFTP), and Well-Differentiated Tumor of Uncertain Malignant Potential (WDT-UMP) remains challenging due to their morphological and molecular similarities. This study aimed to investigate the protein distinctions among these three thyroid tumors and discover biological tumorigenesis through proteomic analysis. We employed total shotgun proteome analysis allowing to discover the quantitative expression of over 1398 proteins from 12 normal thyroid tissues, 13 IEFVPTC, 11 NIFTP, and 10 WDT-UMP. Principal component analysis revealed a distinct separation of IEFVPTC and normal tissue samples, distinguishing them from the low-risk tumor group (NIFTP and WDT-UMP). IEFVPTC exhibited the highest number of differentially expressed proteins (DEPs) compared to the other tumors. No discriminatory proteins between NIFTP and WDT-UMP were identified. Moreover, DEPs in IEFVPTC were significantly associated with thyroid tumor progression pathways. Certain hub genes linked to the response of immune checkpoint inhibitor therapy, revealing the potential predictor of prognosis. In conclusion, the proteomic profile of IEFVPTC differs from that of low-risk tumors. These findings may provide valuable insights into tumor biology and offer a basis for developing novel therapeutic strategies for follicular-patterned thyroid neoplasms.

Analysis of Immunohistochemical Expression of BRAF (V600E) Mutation in Serrated Colorectal Polyps: A Study from Tertiary Hospital in Oman.

BACKGROUND AND AIM: Colorectal cancer (CRC) is considered one of the most common cancers in the world. Serrated polyps were found to be precursor lesions for CRC. BRAF mutation (V600E) has been strongly linked to the development of these lesions. No previous study concerning BRAF immunohistochemical expression in serrated polyps- was done in Oman. The primary objective of our study was to assess the prevalence of BRAF (V600E) mutation in serrated colorectal polyps in the Omani population. The secondary objectives were to assess the prevalence of serrated polyps and their characteristic features: type, site and size as well as the relationship between BRAF (V600E) mutation and polyp type, site and size. MATERIALS AND METHODS: Ninety-one hyperplastic polyps (HP) (76.5%), 24 sessile serrated lesions (SSL) (20.2%) and 4 cases of tubular adenomas with low grade dysplasia (3.4%) were studied for BRAF (V600E) immunohistochemical expression. No case of traditional serrated adenoma (TSA) was present. Control cases of craniopharyngioma and papillary thyroid carcinoma were included. RESULTS: BRAF (V600E) IHC was positive in 63 of the HP polyps (69.2%), 13 SSLs (54.2%) and none of the adenomatous polyps. The majority of positive polyps (75.0%) were ≤5 mm in size, 17.9% were 5-10 mm and 7.1% were ≥10 mm in size.  The majority of BRAF (V600E) positive polyps (68.1 %) were in the distal colon and 31.9 % were in the proximal colon. The majority of positive cases for BRAF (V600E) were showing multiple polyps (61.8 %). None of the tubular adenomas showed any BRAF (V600E) positivity. CONCLUSION: Serrated polyps are now well known for their potential to develop CRC. Immunohistochemistry is an easy and reproducible way to detect BRAF (V600E) mutation. Our study showed there is high prevalence (64.3%) of BRAF mutation in serrated polyps in the Omani population. The majority of these polyps- were HP and SSL; and ≤5 mm in size and located in the distal colon.

Identification and validation of potential common biomarkers for papillary thyroid carcinoma and Hashimoto's thyroiditis through bioinformatics analysis and machine learning.

There is a growing body of evidence suggesting that Hashimoto's thyroiditis (HT) may contribute to an increased risk of papillary thyroid carcinoma (PTC). However, the exact relationship between HT and PTC is still not fully understood. The objective of this study was to identify potential common biomarkers that may be associated with both PTC and HT. Three microarray datasets from the GEO database and RNA-seq dataset from TCGA database were collected to identify shared differentially expressed genes (DEGs) between HT and PTC. A total of 101 genes was identified as common DEGs, primarily enriched inflammation- and immune-related pathways through GO and KEGG analysis. We performed protein-protein interaction analysis and identified six significant modules comprising a total of 29 genes. Subsequently, tree hub genes (CD53, FCER1G, TYROBP) were selected using random forest (RF) algorithms for the development of three diagnostic models. The artificial neural network (ANN) model demonstrates superior performance. Notably, CD53 exerted the greatest influence on the ANN model output. We analyzed the protein expressions of the three genes using the Human Protein Atlas database. Moreover, we observed various dysregulated immune cells that were significantly associated with the hub genes through immune infiltration analysis. Immunofluorescence staining confirmed the differential expression of CD53, FCER1G, and TYROBP, as well as the results of immune infiltration analysis. Lastly, we hypothesise that benzylpenicilloyl polylysine and aspirinmay be effective in the treatment of HT and PTC and may prevent HT carcinogenesis. This study indicates that CD53, FCER1G, and TYROBP play a role in the development of HT and PTC, and may contribute to the progression of HT to PTC. These hub genes could potentially serve as diagnostic markers and therapeutic targets for PTC and HT.

Prediction of the Aggressive Clinical Course of Papillary Thyroid Carcinoma Based on Fine Needle Aspiration Biopsy Molecular Testing.

Molecular genetic events are among the numerous factors affecting the clinical course of papillary thyroid carcinoma (PTC). Recent studies have demonstrated that aberrant expression of miRNA, as well as different thyroid-related genes, correlate with the aggressive clinical course of PTC and unfavorable treatment outcomes, which opens up new avenues for using them in the personalization of the treatment strategy for patients with PTC. In the present work, our goal was to assess the applicability of molecular markers in the preoperative diagnosis of aggressive variants of papillary thyroid cancer. The molecular genetic profile (expression levels of 34 different markers and BRAF mutations) was studied for 108 cytology specimens collected by fine-needle aspiration biopsy in patients with PTC having different clinical manifestations. Statistically significant differences with adjustment for multiple comparisons (p < 0.0015) for clinically aggressive variants of PTC were obtained for four markers: miRNA-146b, miRNA-221, fibronectin 1 (FN1), and cyclin-dependent kinase inhibitor 2A (CDKN2A) genes. A weak statistical correlation (0.0015 < p < 0.05) was observed for miRNA-31, -375, -551b, -148b, -125b, mtDNA, CITED1, TPO, HMGA2, CLU, NIS, SERPINA1, TFF3, and TMPRSS4. The recurrence risk of papillary thyroid carcinoma can be preoperatively predicted using miRNA-221, FN1, and CDKN2A genes.

The neurotransmitter calcitonin gene-related peptide shapes an immunosuppressive microenvironment in medullary thyroid cancer.

Neurotransmitters are key modulators in neuro-immune circuits and have been linked to tumor progression. Medullary thyroid cancer (MTC), an aggressive neuroendocrine tumor, expresses neurotransmitter calcitonin gene-related peptide (CGRP), is insensitive to chemo- and radiotherapies, and the effectiveness of immunotherapies remains unknown. Thus, a comprehensive analysis of the tumor microenvironment would facilitate effective therapies and provide evidence on CGRP's function outside the nervous system. Here, we compare the single-cell landscape of MTC and papillary thyroid cancer (PTC) and find that expression of CGRP in MTC is associated with dendritic cell (DC) abnormal development characterized by activation of cAMP related pathways and high levels of Kruppel Like Factor 2 (KLF2), correlated with an impaired activity of tumor infiltrating T cells. A CGRP receptor antagonist could offset CGRP detrimental impact on DC development in vitro. Our study provides insights of the MTC immunosuppressive microenvironment, and proposes CGRP receptor as a potential therapeutic target.

Exploring markers of immunoresponsiveness in papillary thyroid carcinoma and future treatment strategies.

BACKGROUND: The study summarizes the potential use of immunotherapy for BRAF-mutated papillary thyroid cancer (PTC) by analyzing the immune profile of City of Hope PTC patient samples and comparing them to the thyroid dataset available in the TCGA database. MATERIALS AND METHODS: PTC cases with available formalin-fixed paraffin-embedded archived tumor tissue were identified. RNA was extracted from the tumor tissue and analyzed by NanoString to evaluate their immune gene expression profile. Immunohistochemistry was used to determine the expression of immune suppressive genes and lymphocytic infiltration into the tumor tissue. Thyroid cancer cell lines (MDA-T32, MDA-T68, MDA-T85, and MDA-T120) were used to determine the correlation between the BRAF inhibition and CD274 expression. RESULTS: The study found that PTC cases with BRAF mutations had higher expression of immune checkpoint markers CD274 and CTLA4, as well as higher tumor-infiltrating lymphocytes, particularly CD4+T cells. Additionally, the study identified immunosuppressive markers expressed by tumor cells like CD73, CD276, and CD200 that could be targeted for immunotherapy. Further experiments using PTC cell lines lead to the conclusion that CD274 expression correlates with BRAF activity and that inhibitors of BRAF could potentially be used in combination with immunotherapy to treat PTC. CONCLUSIONS: These findings suggest that PTC cases with BRAF mutations or high expression may be correlated with an immune hot signature and could benefit from immunotherapeutic strategies.

Distinct transcriptional and prognostic impacts of TERT promoter mutations C228T and C250T in papillary thyroid carcinoma.

TERT promoter mutations C228T and C250T are associated with disease aggressiveness and poor clinical outcomes in patients with papillary thyroid carcinomas. However, very little is known about the transcriptional consequences of these mutations and whether they both carry similar oncogenic potential. Here we characterized the transcriptional disturbances and clinical outcomes associated with the presence of each of these two mutations using data derived from The Cancer Genome Atlas. We observed that tumors harboring the C228T mutation (n = 27) exhibited a 16-fold increase in TERT mRNA levels (P = 5.3 × 10-42), whereas C250T tumors (n = 8) showed only a two-fold increase in expression (P = 0.034). The C228T mutation was associated with the activation of signaling pathways controlling the cell cycle, cellular division, and extracellular matrix degradation. Univariate analysis demonstrated that the C228T mutation was associated with older age at diagnosis, large tumor size, lymph node invasion, and distant metastases at diagnosis. The C228T mutation was also associated with worse progression-free interval (PFI) in comparison to WT tumors (HR = 5,04; P < 0.001). This association remained significant in a multivariate analysis (HR = 3.74, P = 0.003) adjusting for BRAF-V600E status and ATA risk group. Our data indicate that TERT promoter mutations C228T and C250T have distinct transcriptional consequences in papillary thyroid carcinoma (PTC), suggesting a greater oncogenic potential for the C228T mutation. TERT promoter mutation C228T may be a useful prognostic marker to identify patients at high risk of distant recurrence. Clinical data for the C250T mutation is still limited, with no evidence up to date to confirm its prognostic significance.