Pathomics and single-cell analysis of papillary thyroid carcinoma reveal the pro-metastatic influence of cancer-associated fibroblasts.

BACKGROUND: Papillary thyroid carcinoma (PTC) is globally prevalent and associated with an increased risk of lymph node metastasis (LNM). The role of cancer-associated fibroblasts (CAFs) in PTC remains unclear. METHODS: We collected postoperative pathological hematoxylin-eosin (HE) slides from 984 included patients with PTC to analyze the density of CAF infiltration at the invasive front of the tumor using QuPath software. The relationship between CAF density and LNM was assessed. Single-cell RNA sequencing (scRNA-seq) data from GSE193581 and GSE184362 datasets were integrated to analyze CAF infiltration in PTC. A comprehensive suite of in vitro experiments, encompassing EdU labeling, wound scratch assays, Transwell assays, and flow cytometry, were conducted to elucidate the regulatory role of CD36+CAF in two PTC cell lines, TPC1 and K1. RESULTS: A significant correlation was observed between high fibrosis density at the invasive front of the tumor and LNM. Analysis of scRNA-seq data revealed metastasis-associated myoCAFs with robust intercellular interactions. A diagnostic model based on metastasis-associated myoCAF genes was established and refined through deep learning methods. CD36 positive expression in CAFs can significantly promote the proliferation, migration, and invasion abilities of PTC cells, while inhibiting the apoptosis of PTC cells. CONCLUSION: This study addresses the significant issue of LNM risk in PTC. Analysis of postoperative HE pathological slides from a substantial patient cohort reveals a notable association between high fibrosis density at the invasive front of the tumor and LNM. Integration of scRNA-seq data comprehensively analyzes CAF infiltration in PTC, identifying metastasis-associated myoCAFs with strong intercellular interactions. In vitro experimental results indicate that CD36 positive expression in CAFs plays a promoting role in the progression of PTC. Overall, these findings provide crucial insights into the function of CAF subset in PTC metastasis.

Genomic characterization of cervical lymph node metastases in papillary thyroid carcinoma following the Chornobyl accident.

Childhood radioactive iodine exposure from the Chornobyl accident increased papillary thyroid carcinoma (PTC) risk. While cervical lymph node metastases (cLNM) are well-recognized in pediatric PTC, the PTC metastatic process and potential radiation association are poorly understood. Here, we analyze cLNM occurrence among 428 PTC with genomic landscape analyses and known drivers (131I-exposed = 349, unexposed = 79; mean age = 27.9 years). We show that cLNM are more frequent in PTC with fusion (55%) versus mutation (30%) drivers, although the proportion varies by specific driver gene (RET-fusion = 71%, BRAF-mutation = 38%, RAS-mutation = 5%). cLNM frequency is not associated with other characteristics, including radiation dose. cLNM molecular profiling (N = 47) demonstrates 100% driver concordance with matched primary PTCs and highly concordant mutational spectra. Transcriptome analysis reveals 17 differentially expressed genes, particularly in the HOXC cluster and BRINP3; the strongest differentially expressed microRNA also is near HOXC10. Our findings underscore the critical role of driver alterations and provide promising candidates for elucidating the biological underpinnings of PTC cLNM.

Application value of multi-gene mutation detection in the clinical management of pediatric papillary thyroid carcinoma: a preliminary exploration.

Objectives: Thyroid cancer rarely occurs in children and adolescents. Molecular markers such as BRAF, RAS, and RET/PTC have been widely used in adult PTC. It is currently unclear whether these molecular markers have equivalent potential for application in pediatric patients. This study aims to explore the potential utility of a multi-gene conjoint analysis based on next-generation targeted sequencing for pediatric papillary thyroid carcinoma (PTC). Materials and methods: The patients diagnosed with PTC (aged 18 years or younger) in the pediatrics department of Lishui District Hospital of Traditional Chinese Medicine were retrospectively screened. A targeted enrichment and sequencing analysis of 116 genes associated with thyroid cancer was performed on paraffin-embedded tumor tissues and paired paracancerous tissue of fifteen children (average age 14.60) and nine adults (average age 49.33) PTC patients. Demographic information, clinical indicators, ultrasonic imaging information and pathological data were collected. The Kendall correlation test was used to establish a correlation between molecular variations and clinical characteristics in pediatric patients. Results: A sample of 15 pediatric PTCs revealed a detection rate of 73.33% (11/15) for driver gene mutations BRAF V600E and RET fusion. Compared to adult PTCs, the genetic mutation landscape of pediatric PTCs was more complex. Six mutant genes overlap between the two groups, and an additional seventeen unique mutant genes were identified only in pediatric PTCs. There was only one unique mutant gene in adult PTCs. The tumor diameter of pediatric PTCs tended to be less than 4cm (p<0.001), and the number of lymph node metastases was more than five (p<0.001). Mutations in specific genes unique to pediatric PTCs may contribute to the onset and progression of the disease by adversely affecting hormone synthesis, secretion, and action mechanisms, as well as the functioning of thyroid hormone signaling pathways. But, additional experiments are required to validate this hypothesis. Conclusion: BRAF V600E mutation and RET fusion are involved in the occurrence and development of adolescent PTC. For pediatric thyroid nodules that cannot be determined as benign or malignant by fine needle aspiration biopsy, multiple gene combination testing can provide a reference for personalized diagnosis and treatment by clinical physicians.

Prognostic prediction of patients having classical papillary thyroid carcinoma with a 4 mRNA-based risk model.

The dysregulation of protein-coding genes involved in various biological functions is closely associated with the progression of thyroid cancer. This study aimed to investigate the effects of dysregulated gene expressions on the prognosis of classical papillary thyroid carcinoma (cPTC). Using expression profiling datasets from the Cancer Genome Atlas (TCGA) database, we performed differential expression analysis to identify differentially expressed genes (DEGs). Cox regression and Kaplan-Meier analysis were used to identify DEGs, which were used to construct a risk model to predict the prognosis of cPTC patients. Functional enrichment analysis unveiled the potential significance of co-expressed protein-encoding genes in tumors. We identified 4 DEGs (SALL3, PPBP, MYH1, and SYNDIG1), which were used to construct a risk model to predict the prognosis of cPTC patients. These 4 genes were independent of clinical parameters and could be functional in cPTC carcinogenesis. Furthermore, PPBP exhibited a strong correlation with poorer overall survival (OS) in the advanced stage of the disease. This study suggests that the 4-gene signature could be an independent prognostic biomarker to improve prognosis prediction in cPTC patients older than 46.

Targeted sequencing of DNA/RNA combined with radiomics predicts lymph node metastasis of papillary thyroid carcinoma.

OBJECTIVE: The aim of our study is to find a better way to identify a group of papillary thyroid carcinoma (PTC) with more aggressive behaviors and to provide a prediction model for lymph node metastasis to assist in clinic practice. METHODS: Targeted sequencing of DNA/RNA was used to detect genetic alterations. Gene expression level was measured by quantitative real-time PCR, western blotting or immunohistochemistry. CCK8, transwell assay and flow cytometry were used to investigate the effects of concomitant gene alterations in PTC. LASSO-logistics regression algorithm was used to construct a nomogram model integrating radiomic features, mutated genes and clinical characteristics. RESULTS: 172 high-risk variants and 7 fusion types were detected. The mutation frequencies in BRAF, TERT, RET, ATM and GGT1 were significantly higher in cancer tissues than benign nodules. Gene fusions were detected in 16 samples (2 at the DNA level and 14 at the RNA level). ATM mutation (ATMMUT) was frequently accompanied by BRAFMUT, TERTMUT or gene fusions. ATMMUT alone or ATM co-mutations were significantly positively correlated with lymph node metastasis. Accordingly, ATM knock-down PTC cells bearing BRAFV600E, KRASG12R or CCDC6-RET had higher proliferative ability and more aggressive potency than cells without ATM knock-down in vitro. Furthermore, combining gene alterations and clinical features significantly improved the predictive efficacy for lymph node metastasis of radiomic features, from 71.5 to 87.0%. CONCLUSIONS: Targeted sequencing of comprehensive genetic alterations in PTC has high prognostic value. These alterations, in combination with clinical and radiomic features, may aid in predicting invasive PTC with higher accuracy.

Estrogen-mediated DNMT1 and DNMT3A recruitment by EZH2 silences miR-570-3p that contributes to papillary thyroid malignancy through DPP4.

BACKGROUND: Papillary thyroid carcinoma (PTC) is a common endocrine malignancy. Studies have indicated that estrogen can regulate the expression of miRNAs in numerous malignancies. MiR-570-3p has been shown to have a regulatory function in various cancers. However, studies of the regulatory function of miR-570-3p and a direct link between estrogen (especially estradiol E2) and miR-570-3p in PTC have not been done. METHODS: Expression of miR-570-3p and its downstream target DPP4 in PTC tissues and cells was predicted using bioinformatics and validated by qRT-PCR and western blot assays. We then performed a series of gain-and-loss experiments to assess the functional significance of miR-570-3p/DPP4 axis in PTC progression in vitro and in vivo. Additionally, the methylation of the miR-570-3p promoter region was examined via bioinformatics analysis and MSP. Finally, the effects of E2 on PTC progression and the correlation between DNMT1/DNMT3A and EZH2 were predicted by bioinformatic tools and proved by luciferase reporter, ChIP, and co-IP assays. RESULTS: In PTC tumor tissues and cell lines, there was a lower expression level and a higher methylation level of miR-570-3p compared to normal tissues and cell lines. DPP4 was identified as the downstream target of miR-570-3p. Overexpression of miR-570-3p reduced the proliferative, migratory, and invasive capabilities, and promoted apoptosis, while overexpression of DPP4 reversed these effects in PTC cells. It was also discovered that DNMT1 and DNMT3A increased the CpG methylation level of the miR-570-3p promoter in an EZH2-dependent manner, which led to decreased expression of miR-570-3p. Furthermore, we observed that estrogen (E2) enhanced the methylation of miR-570-3p and suppressed its expression levels, resulting in augmented tumor growth in vivo in PTC. CONCLUSION: Estrogen regulates the EZH2/DNMTs/miR-570-3p/DPP4 signaling pathway to promote PTC progression.

Circ_0004851 regulates the molecular mechanism of miR-296-3p/FGF11 in the influence of high iodine on PTC.

The prevalence of papillary thyroid cancer (PTC) has been rising in recent years. Despite its relatively low mortality, PTC frequently metastasizes to lymph nodes and often recurs, posing significant health and economic burdens. The role of iodine in the pathogenesis and advancement of thyroid cancer remains poorly understood. Circular RNAs (circRNAs) are recognized to function as competing endogenous RNAs (ceRNAs) that modulate gene expression and play a role in various cancer stages. Consequently, this research aimed to elucidate the mechanism by which circRNA influences the impact of iodine on PTC. Our research indicates that high iodine levels can exacerbate the malignancy of PTC via the circ_0004851/miR-296-3p/FGF11 axis. These insights into iodine's biological role in PTC and the association of circRNA with the disease could pave the way for novel biomarkers and potentially effective therapeutic strategies to mitigate PTC progression.

Exploration of the prognostic value of methylation regulators related to m5C in papillary thyroid carcinoma.

The incidence of papillary thyroid carcinoma (PTC) has increased significantly in recent years, and for patients with metastatic and recurrent PTC, the options for treatment currently available are insufficient. To date, the exact molecular mechanism underlying PTC is still not fully understood. 5-Methylcytosine (m5C) RNA methylation is associated with the prognosis of a variety of tumors. However, the molecular mechanisms and biomarkers associated with m5C in the diagnosis, treatment, and prognosis of this disease have not been fully elucidated. Ten m5C regulators with significantly different expression levels were included in this study. Immune infiltration analysis revealed significant negative correlations between most of these regulators and regulatory T cells. TRDMT1, NSUN5, and NSUN6 had high weights and strong correlations in the protein-protein interaction network. Using gene ontology, Kyoto Encyclopedia of Genes and Genomes, and gene set enrichment analysis, 1489 differentially expressed genes were screened from The Cancer Genome Atlas messenger RNA matrix, indicating that these differentially expressed genes were significantly enriched in various pathways and functions related to cancers. Four m5C regulators, NSUN2, NSUN4, NSUN6, and DNMT3B, were screened as prognostic markers by least absolute shrinkage and selection operator regression analysis, and NSUN2 and NSUN6 were identified as risk factors for poor prognosis. We found that the prognostic prediction model constructed using the m5C regulators NSUN2, NSUN4, NSUN6, and DNMT3B showed good prognostic prediction ability and diagnostic ability. This model was applied to predict the survival probability of patients with PTC, the prediction ability of 5-year survival was the best. The multi-factor prognostic prediction model combined with the tumor node metastasis stage and risk score grouping showed better prognostic predictive power.

B7-H3 and ICAM-1 are potentially therapeutic targets for thyroid carcinoma.

Although most differentiated thyroid carcinoma has a clinically favorable prognosis, some of specific types of thyroid cancer (such as anaplastic thyroid carcinoma and advanced papillary thyroid carcinoma) show fatal outcomes and require novel treatments. Immunotherapy is a promising avenue for the treatment of advanced thyroid carcinoma. B7-H3 (B7 homolog 3 protein) and ICAM-1 (intercellular adhesion molecule 1), as two important immune checkpoints (ICPs), is becoming hopeful target spots for immunotherapy. A growing amount of evidence has suggested that B7-H3 and ICAM-1 are upregulated in papillary thyroid carcinoma. However, their expression level in specific types of thyroid cancer remains largely unclear. In the present study, we explored the expression level of B7-H3 and ICAM-1 in different types of thyroid carcinoma. In the groups of the TCGA cohort, both B7-H3 and ICAM-1 mRNA were highly expressed in thyroid carcinoma. Furthermore, the patients with Stage2, 61-80y, Follicular thyroid papillary carcinoma and N0 had lower B7-H3 and ICAM-1 mRNA expression. In the groups of our cohort, PTCs and ATCs showed frequently moderate to strong expression of B7-H3 and ICAM-1 protein expression. The significant relevance of B7-H3 staining score with ICAM-1 staining score was observed in TCGA database and our cohort, which might open avenues for the combination therapy in advanced thyroid cancer.

[Bioinformatic analysis of CCND2 expression in papillary thyroid carcinoma and its impact on immune infiltration].

OBJECTIVE: To investigate cyclin D2 (CCND2) expression in papillary thyroid carcinoma (PTC) and its association with the clinicopathological features. METHODS: The public databases TCGA, TIMER 2.0 and UALCAN were used to explore CCND2 expression level in PTC and adjacent tissues, and its diagnostic value for PTC was analyzed using ROC curves. GO enrichment analysis of CCND2-related differentially expressed genes (DEGs) in PTC was performed, and tumor immune infiltration of CCND2 in thyroid cancer was analyzed using TIMER database and CIBERSORT data source. RT-qPCR and Western blot were used to detect CCND2 expression in normal human thyroid cell line Nthy-ori-3-1 and human PTC cell lines TPC-1 and BCPAP. CCND2 expression was also detected in clinical specimens of PTC and adjacent tissues by immunohistochemistry, and its correlation with clinicopathological features of the patients were analyzed. RESULTS: Informatic analysis revealed significantly higher CCND2 mRNA expression in thyroid cancer than in the adjacent tissues (P < 0.001) in close correlation with tumor stage, gender, age, pathological subtype, and lymph node involvement (P < 0.05). ROC curve analysis showed that at the cutoff value of 4.983, the diagnostic sensitivity, specificity, and accuracy of CCND2 expression for PTC was 83.6%, 94.9%, and 78.5%, respectively. CCND2 expression was positively correlated with B cells, CD4+ T cells, and macrophages (P < 0.001) and negatively with CD8+ T cells (P < 0.01), and also correlated with memory B-cell infiltration, CD4+ T-cell memory activation, M2 macrophages, resting mast cells, and mast cell activation (P < 0.05). RT-qPCR, Western blot and immunohistochemistry showed significantly higher CCND2 expression in the PTC cells than in Nthy-ori-3-1 cells (P < 0.01) and also in clinical PTC tissues than in the adjacent tissues (P < 0.05) in correlation with tumor size, lymph node metastasis and TNM stage (P < 0.05). CONCLUSION: CCND2 overexpression is closely correlated with tumor progression and immune cell infiltration in PTC patients..

Transcriptomic characteristics according to tumor size and SUVmax in papillary thyroid cancer patients.

The SUVmax is a measure of FDG uptake and is related with tumor aggressiveness in thyroid cancer, however, its association with molecular pathways is unclear. Here, we investigated the relationship between SUVmax and gene expression profiles in 80 papillary thyroid cancer (PTC) patients. We conducted an analysis of DEGs and enriched pathways in relation to SUVmax and tumor size. SUVmax showed a positive correlation with tumor size and correlated with glucose metabolic process. The genes that indicate thyroid differentiation, such as SLC5A5 and TPO, were negatively correlated with SUVmax. Unsupervised analysis revealed that SUVmax positively correlated with DNA replication(r = 0.29, p = 0.009), pyrimidine metabolism(r = 0.50, p < 0.0001) and purine metabolism (r = 0.42, p = 0.0001). Based on subgroups analysis, we identified that PSG5, TFF3, SOX2, SL5A5, SLC5A7, HOXD10, FER1L6, and IFNA1 genes were found to be significantly associated with tumor aggressiveness. Both high SUVmax PTMC and macro-PTC are enriched in pathways of DNA replication and cell cycle, however, gene sets for purine metabolic pathways are enriched only in high SUVmax macro-PTC but not in high SUVmax PTMC. Our findings demonstrate the molecular characteristics of high SUVmax tumor and metabolism involved in tumor growth in differentiated thyroid cancer.

Identification and validation of a prognostic anoikis-related gene signature in papillary thyroid carcinoma by integrated analysis of single-cell and bulk RNA-sequencing.

Papillary thyroid carcinoma (PTC) prognosis may be deteriorated due to the metastases, and anoikis palys an essential role in the tumor metastasis. However, the potential effect of anoikis-related genes on the prognosis of PTC was unclear. The mRNA and clinical information were obtained from the cancer genome atlas database. Hub genes were identified and risk model was constructed using Cox regression analysis. Kaplan-Meier (K-M) curve was applied for the survival analysis. Immune infiltration and immune therapy response were calculated using CIBERSORT and TIDE. The identification of cell types and cell interaction was performed by Seurat, SingleR and CellChat packages. GO, KEGG, and GSVA were applied for the enrichment analysis. Protein-protein interaction network was constructed in STRING and Cytoscape. Drug sensitivity was assessed in GSCA. Based on bulk RNA data, we identified 4 anoikis-related risk signatures, which were oncogenes, and constructed a risk model. The enrichment analysis found high risk group was enriched in some immune-related pathways. High risk group had higher infiltration of Tregs, higher TIDE score and lower levels of monocytes and CD8 T cells. Based on scRNA data, we found that 4 hub genes were mainly expressed in monocytes and macrophages, and they interacted with T cells. Hub genes were significantly related to immune escape-related genes. Drug sensitivity analysis suggested that cyclin dependent kinase inhibitor 2A may be a better chemotherapy target. We constructed a risk model which could effectively and steadily predict the prognosis of PTC. We inferred that the immune escape may be involved in the development of PTC.

Targeting miR-31 represses tumourigenesis and dedifferentiation of BRAFV600E-associated thyroid carcinoma.

BACKGROUND: BRAFV600E is the most common genetic mutation in differentiated thyroid cancer (DTC) occurring in 60% of patients and drives malignant tumour cell phenotypes including proliferation, metastasis and immune-escape. BRAFV600E-mutated papillary thyroid cancer (PTC) also displays greatly reduced expression of thyroid differentiation markers, thus tendency to radioactive iodine (RAI) refractory and poor prognosis. Therefore, understanding the molecular mechanisms and main oncogenic events underlying BRAFV600E will guide future therapy development. METHODS: Bioinformatics and clinical specimen analyses, genetic manipulation of BRAFV600E-induced PTC model, functional and mechanism exploration guided with transcriptomic screening, as well as systematic rescue experiments were applied to investigate miR-31 function within BRAFV600E-induced thyroid cancer development. Besides, nanoparticles carrying miR-31 antagomirs were testified to alleviate 131I iodide therapy on PTC models. RESULTS: We identify miR-31 as a significantly increased onco-miR in BRAFV600E-associated PTC that promotes tumour progression, metastasis and RAI refractoriness via sustained Wnt/ß-catenin signalling. Mechanistically, highly activated BRAF/MAPK pathway induces miR-31 expression via c-Jun-mediated transcriptional regulation across in vitro and transgenic mouse models. MiR-31 in turn facilitates ß-catenin stabilisation via directly repressing tumour suppressors CEBPA and DACH1, which direct the expression of multiple essential Wnt/ß-catenin pathway inhibitors. Genetic functional assays showed that thyroid-specific knockout of miR-31 inhibited BRAFV600E-induced PTC progression, and strikingly, enhanced expression of sodium-iodide symporter and other thyroid differentiation markers, thus promoted 131I uptake. Nanoparticle-mediated application of anti-miR-31 antagomirs markedly elevated radio-sensitivity of BRAFV600E-induced PTC tumours to 131I therapy, and efficiently suppressed tumour progression in the pre-clinical mouse model. CONCLUSIONS: Our findings elucidate a novel BRAF/MAPK-miR-31-Wnt/ß-catenin regulatory mechanism underlying clinically BRAFV600E-associated DTC tumourigenesis and dedifferentiation, also highlight a potential adjuvant therapeutic strategy for advanced DTC.

BRAF mutation, selected miRNAs and genes expression in primary papillary thyroid carcinomas and local lymph node metastases.

Mutations in cancer-related genes are now known to be accompanied by epigenetic events in carcinogenesis by modification of the regulatory pathways and expression of genes involved in the pathobiology. Such cancer-related mutations, miRNAs and gene expression may be promising molecular markers of the most common papillary thyroid carcinoma (PTC). However, there are limited data on their relationships. The aim of this study was to analyse the interactions between BRAF mutations, selected microRNAs (miR-21, miR-34a, miR-146b, and miR-9) and the expression of selected genes (LGALS3, NKX2-1, TACSTD2, TPO) involved in the pathogenesis of PTC. The study cohort included 60 primary papillary thyroid carcinomas (PTC) that were classified as classical (PTC/C; n=50) and invasive follicular variant (PTC/F; n=10), and 40 paired lymph node metastases (LNM). BRAF mutation status in primary and recurrent/persistent papillary thyroid carcinomas was determined. The mutation results were compared both between primary and metastatic cancer tissue, and between BRAF mutation status and selected genes and miRNA expression in primary PTC. Furthermore, miRNAs and gene expression were compared between primary PTCs and non-neoplastic tissue, and local lymph node metastatic tumor, respectively. All studied markers showed several significant mutual interactions and contexts. In conclusion, to the best our knowledge, this is the first integrated study of BRAF mutational status, the expression levels of mRNAs of selected genes and miRNAs in primary PTC, and paired LNM.

Cancer-associated fibroblast-derived periostin promotes papillary thyroid tumor growth through integrin-FAK-STAT3 signaling.

Background: Periostin (POSTN) is a critical extracellular matrix protein in various tumor microenvironments. However, the function of POSTN in thyroid cancer progression remains largely unknown. Methods: Postn and Rag1 knock-out mice and orthotopic mouse models were used to determine the role of POSTN on papillary thyroid tumor progression. Immunofluorescence, cell co-culture, fluorescence in situ hybridization, chromatin immunoprecipitation assay, recombinant protein and inhibitor treatment were performed to explore the underlying mechanisms of POSTN-promoted papillary thyroid tumor growth. Results: POSTN is up-regulated in papillary thyroid tumors and negatively correlates with the overall survival of patients with thyroid cancer. Cancer-associated fibroblast (CAF)-derived POSTN promotes papillary thyroid tumor growth in vivo and in vitro. POSTN deficiency in CAFs significantly impairs CAF-promoted papillary thyroid tumor growth. POSTN promotes papillary thyroid tumor cell proliferation and IL-4 expression through integrin-FAK-STAT3 signaling. In turn, tumor cell-derived IL-4 induces the activation of CAFs and stimulates POSTN expression by activating STAT6. We reveal the crucial role of CAF-derived POSTN and tumor cell-derived IL-4 in driving the development of papillary thyroid tumors through the POSTN-integrin-FAK-STAT3-IL-4 pathway in tumor cells and IL-4-STAT6-POSTN signaling in CAFs. Conclusion: Our findings underscore the significance of POSTN and IL-4 as critical molecular mediators in the dynamic interplay between CAFs and tumor cells, ultimately supporting the growth of papillary thyroid tumors.

Thyroid papillary carcinoma combined with primary follicular lymphoma: a case report.

BACKGROUND: Papillary thyroid carcinoma (PTC) stands out as the most prevalent epithelial malignant thyroid tumor. Thyroid primary follicular lymphoma (PFL) represents a rare malignant tumor originating from mesenchymal tissues. The concurrent occurrence of PTC and PFL is exceptionally rare, particularly in the context of Hashimoto's thyroiditis, presenting significant challenges in clinical diagnosis and treatment. CASE DEMONSTRATION: A 44-year-old female patient presented with a neck mass persisting for over 1 month. The patient underwent surgery, and the incised tissues were subjected to pathology examinations, along with immunohistochemistry and next-generation sequencing tests suggestive of an EZH2 gene mutation in the tumor cells. The final pathological diagnosis confirmed the presence of PTC combined with PFL. Following a 27-month follow-up, the patient displayed no signs of recurrence or metastasis. CONCLUSIONS: The concurrent occurrence of PTC and PFL poses notable challenges in clinical practice, requiring careful consideration in diagnosis and treatment. Herein, we present a rare case of PTC combined with PFL featuring an EZH2 gene mutation, which can be easily overlooked in the context of Hashimoto's thyroiditis. The patient's favorable response to surgical and radiotherapeutic interventions underscores the importance of accurate diagnosis and tailored treatment strategies in similar cases.

Next-generation sequencing identified that RET variation associates with lymph node metastasis and the immune microenvironment in thyroid papillary carcinoma.

BACKGROUND: To date, although most thyroid carcinoma (THCA) achieves an excellent prognosis, some patients experience a rapid progression episode, even with differentiated THCA. Nodal metastasis is an unfavorable predictor. Exploring the underlying mechanism may bring a deep insight into THCA. METHODS: A total of 108 THCA from Chinese patients with next-generation sequencing (NGS) were recruited. It was used to explore the gene alteration spectrum of THCA and identify gene alterations related to nodal metastasis in papillary thyroid carcinoma (PTC). The Cancer Genome Atlas THCA cohort was further studied to elucidate the relationship between specific gene alterations and tumor microenvironment. A pathway enrichment analysis was used to explore the underlying mechanism. RESULTS: Gene alteration was frequent in THCA. BRAF, RET, POLE, ATM, and BRCA1 were the five most common altered genes. RET variation was positively related to nodal metastasis in PTC. RET variation is associated with immune cell infiltration levels, including CD8 naïve, CD4 T and CD8 T cells, etc. Moreover, Step 3 and Step 4 of the cancer immunity cycle (CIC) were activated, whereas Step 6 was suppressed in PTC with RET variation. A pathway enrichment analysis showed that RET variation was associated with several immune-related pathways. CONCLUSION: RET variation is positively related to nodal metastasis in Chinese PTC, and anti-tumor immune response may play a role in nodal metastasis triggered by RET variation.

Columnar Cell Thyroid Carcinoma: A Heterogeneous Entity Demonstrating Overlap Between Papillary Thyroid Carcinoma and Follicular Neoplasms.

BACKGROUND: Columnar cell papillary thyroid carcinoma (CC-PTC) is a morphologic subtype of papillary thyroid carcinoma with a variable prognosis. It is characterized by neoplastic thyroid follicular-derived cells with pseudostratified columnar morphology arranged in papillary or follicular structures with supranuclear or subnuclear vacuoles. The molecular profile of this subtype has only recently come under scrutiny, with mixed results. The aim of this study is to further explore the morphologic, immunohistochemical, and genetic profile of CC-PTC, as well as to correlate these features with clinical outcomes. METHODS: CC-PTC cases were identified from 3 institutions. Immunohistochemistry (ER, CDX2) and molecular testing (DNA and RNA sequencing) were performed. Clinicopathologic parameters and patient outcomes were recorded. RESULTS: Twelve cases (2006-2023) were identified, all in adults (age 45-91). Two presented with disease outside the thyroid gland (neck and mediastinum) and two presented with distant metastasis. Four were high-grade differentiated thyroid carcinomas (necrosis or mitoses), one of which died of disease. Four were noninvasive or minimally invasive, one of which locally recurred. Three patients had lymph node metastases. ER and CDX2 were positive in 73% and 50%, respectively. Pathogenic mutations were found in TERT promoter (n = 3), RAS (n = 2), ATM, NOTCH1, APC, and ESR1, along with cases bearing AGK::BRAF fusion (n = 1), BRAF VE1 expression (n = 1), and NF2 loss (n = 1). CONCLUSIONS: This study represents the largest molecularly defined cohort of non-oncocytic thyroid carcinomas with columnar cell morphology. These tumors represent a genetically and behaviorally heterogeneous group of neoplasms, some of which have RAS-like or follicular neoplasm-like genetics, some of which have BRAF-p.V600E-like or classic papillary thyroid carcinoma-like genetics, and some of which remain unclear. Noninvasive or minimally invasive tumors showed an indolent course compared to those with angioinvasion, gross extrathyroidal growth, or high-grade morphology. Consideration could be given to reclassification of this neoplasm outside of the subtyping of papillary thyroid carcinoma in light of its genetic diversity, distinct morphology, and clinical behavior more closely aligned with follicular thyroid neoplasms.

Diagnostic value of FNAC combined with BRAFV600E mutation detection in Hashimoto's thyroiditis complicated with papillary thyroid carcinoma.

Background: This study aimed to analyze the effect of preoperative fine needle aspiration cytology (FNAC) combined with BRAFV600E mutation detection as compared to that of fine needle aspiration cytology alone on the diagnostic performance of papillary thyroid carcinoma (PTC) combined with Hashimoto's thyroiditis (HT). Method: Patients with thyroid nodules in Hashimoto's thyroiditis, who underwent fine-needle aspiration cytology examination and BRAFV600E mutation detection in the puncture eluate at the outpatient clinic, were selected. Finally, 122 patients received surgical treatment and were included in the study. We used postoperative pathological results as the gold standard. Accordingly, we compared the sensitivity, specificity and accuracy of preoperative FNAC alone and FNAC combined with BRAFV600E mutation detection in for the diagnosis of PTC combined with HT. Results: For PTC patients with HT, the sensitivity of FNAC diagnosis was 93.69%, the specificity was 90.90% and the accuracy was 93.44%. However, the sensitivity, specificity and accuracy of FNAC combined with BRAFV600E mutation detection were 97.30%, 90.90% and 96.72%, respectively. Therefore, combined detection can improve the sensitivity and accuracy of diagnosis (p<0.05). Conclusion: FNAC combined with eluent BRAFV600E mutation detection can improve the sensitivity and accuracy of diagnosis of PTC in the background of HT.

Papillary Thyroid Cancer Remodels the Genetic Information Processing Pathways.

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