Predictors of recurrence after total thyroidectomy in 1,611 patients with papillary thyroid carcinoma: postoperative stimulated serum thyroglobulin and ATA initial and dynamic risk assessment.

Objective: Despite a favorable prognosis, some patients with papillary thyroid carcinoma (PTC) develop recurrence. The objective of this study was to examine the impact of the combination of initial American Thyroid Association (ATA) risk stratification with serum level of postoperative stimulated thyroglobulin (s-Tg) in predicting recurrence in patients with PTC and compare the results with an assessment of response to initial therapy (dynamic risk stratification). Subjects and methods: We retrospectively analyzed 1,611 patients who had undergone total thyroidectomy for PTC, followed in most cases (87.3%) by radioactive iodine (RAI) administration. Clinicopathological features and s-Tg levels obtained 3 months postoperatively were evaluated. The patients were stratified according to ATA risk categories. Nonstimulated thyroglobulin levels and imaging studies obtained during the first year of follow-up were used to restage the patients based on response to initial therapy. Results: After a mean follow-up of 61.5 months (range 12-246 months), tumor recurrence was diagnosed in 99 (6.1%) patients. According to ATA risk, recurrence was identified in 2.3% of the low-risk, 9% of the intermediate-risk, and 25% of the high-risk patients (p < 0.001). Using a receiver operating characteristic curve approach, a postoperative s-Tg level of 10 ng/mL emerged as the ideal cutoff value, with positive and negative predictive values of 24% and 97.8%, respectively (p < 0.001). Patients with low to intermediate ATA risk with postoperative s-Tg levels < 10 ng/mL and excellent response to treatment had a very low recurrence rate (<0.8%). In contrast, higher recurrence rates were observed in intermediate-riskto high-risk patients with postoperative s-Tg > 10 ng/mL and indeterminate response (25%) and in those with incomplete response regardless of ATA category or postoperative s-Tg value (38.5-87.5%). Using proportion of variance explained (PVE), the predicted recurrence using the ATA initial risk assessment alone was 12.7% and increased to 29.9% when postoperative s-Tg was added to the logistic regression model and 49.1% with dynamic risk stratification. Conclusion: The combination of ATA staging system and postoperative s-Tg can better predict the risk of PTC recurrence. Initial risk estimates can be refined based ondynamic risk assessment following response to therapy, thus providing a useful guide for follow-up recommendations.

Correlation Between the Clinicopathological Features of Papillary Thyroid Carcinoma Complicated with Hashimoto's Thyroiditis, BRAF V600E Gene Mutation, and RET Gene Rearrangement.

OBJECTIVE: To analyse the expression of BRAF V600E protein and RET gene rearrangement in papillary thyroid carcinoma (PTC) combined with Hashimoto's thyroiditis (HT) and to explore its clinical and pathological significance. STUDY DESIGN: Observational study. Place and Duration of the Study: Department of Pathology, East China Normal University (Wuhu No. 2 People's Hospital), Wuhu, China, from January 2019 to July 2022. METHODOLOGY: The study population of 150 patients who underwent central lymph node dissection. They were divided into two groups: the PTC group (76/150, 50.7%) and the PTC with HC group (74/150, 49.3%). The expression of BRAF V600E protein was detected using immunohistochemistry, and the RET gene rearrangement status was detected using fluorescence in situ hybridisation. The detection results and clinical pathological characteristics were statistically analysed. RESULTS: Compared with the PTC group, the prevalence rate of female PTC in HT group was significantly higher than that of the male group, the rate of lymph node metastasis was lower, and the proportion of tumour diameter ≤ 1cm was higher (p < 0.05). However, no significant difference in patient age and multifocality was found between the two groups (p > 0.05). The BRAF V600E positive rate in the PTC combined with HT group (48.6%) was lower than in the PTC group (73.7%), and the RET gene rearrangement positive rate was higher than in the PTC group (p < 0.05). The expression of BRAF V600E protein in PTC combined with HT is correlated with multifocality (p < 0.05), and there is a correlation between RET gene rearrangement and the gender of the patient in the PTC group (p < 0.05). CONCLUSION: There is a lower rate of BRAF V600E protein positivity in PTC combined with HT patients, as well as a higher rate of RET gene rearrangements positive in PTC combined with HT patients. There is a correlation between multifocality and BRAF V600E protein expression. KEY WORDS: Papillary thyroid carcinoma, Hashimoto's thyroiditis, BRAF V600E protein, RET gene rearrangement.

Impact of age on central lymph nodes involvement in papillary thyroid cancer.

BACKGROUND: Total thyroidectomy is the main line of treatment for papillary thyroid cancer. Central lymph node dissection (CLND) is still debatable. In this study, we aimed to correlate the central lymph node status with the age of patients. METHODS: This is a retrospective study including patients with papillary thyroid cancer (PTC) who underwent total thyroidectomy and CLND at a tertiary cancer center during the period from January 2012 to September 2022. Patients were subdivided into 3groups: patients younger than 20 years old, patients between 20 and 40 years old, and patients older than 40 years old. Correlation between central lymph node status, lateral lymph node status, and harvest count with each other and between age groups was done. RESULTS: 315 patients were included. The younger the age group the higher the possibility of harboring positive central nodes, however, the positivity of lateral nodes was similar. Neither central nodal harvest nor positive central node count significantly differed between groups. The lateral nodal harvest was significantly higher in the < 20 years group with no affection to the number of positive nodes retrieved. The younger the age group the longer the disease-free survival (DFS). CONCLUSION: We can conclude that patients younger than twenty years had a higher probability of harboring malignancy in central nodes and higher lateral node harvest on dissection. In contrast, they do have a lower incidence of recurrence.

Functional analysis of ESM1 by shRNA-mediated knockdown of its expression in papillary thyroid cancer cells.

OBJECTIVE: Endothelial specific molecule-1 (ESM1) is implicated as an oncogene in multiple human cancers. However, the function of ESM1 in papillary thyroid cancer (PTC) is not well understood. The current study aimed to investigate the effect of ESM1 on the growth, migration, and invasion of PTC to provide a novel perspective for PTC treatment. METHODS: The expression levels of ESM1 in PTC tissues form 53 tumor tissue samples and 59 matching adjacent normal tissue samples were detected by immunohistochemical analysis. Knockdown of ESM1 expression in TPC-1 and SW579 cell lines was established to investigate its role in PTC. Moreover, cell proliferation, apoptosis, wound healing, and transwell assays were conducted in vitro to assess cell proliferation, migration and invasion. RESULTS: The findings revealed that ESM1 expression was significantly higher in PTC tissues than that found in paraneoplastic tissues (P<0.0001). Knockdown of ESM1 expression inhibited the proliferation, migration, and invasion of TPC-1 and SW579 cells in vitro. Compared with the control group, the mRNA and protein levels of ESM1 in PTC cells were significantly reduced following knockdown of its expression (P<0.01). In addition, ESM1-knockdown cells indicated decreased proliferation and decreased migratory and invasive activities (P<0.01, P<0.01, P<0.001, respectively). CONCLUSIONS: ESM1 was identified as a major gene in the occurrence and progression of PTC, which could increase the proliferation, migration, and invasion of PTC cells. It may be a promising diagnostic and therapeutic target gene.

Predicting central cervical lymph node metastasis in papillary thyroid carcinoma with Hashimoto's thyroiditis: a practical nomogram based on retrospective study.

Background: In papillary thyroid carcinoma (PTC) patients with Hashimoto's thyroiditis (HT), preoperative ultrasonography frequently reveals the presence of enlarged lymph nodes in the central neck region. These nodes pose a diagnostic challenge due to their potential resemblance to metastatic lymph nodes, thereby impacting the surgical decision-making process for clinicians in terms of determining the appropriate surgical extent. Methods: Logistic regression analysis was conducted to identify independent risk factors associated with central lymph node metastasis (CLNM) in PTC patients with HT. Then a prediction model was developed and visualized using a nomogram. The stability of the model was assessed using ten-fold cross-validation. The performance of the model was further evaluated through the use of ROC curve, calibration curve, and decision curve analysis. Results: A total of 376 HT PTC patients were included in this study, comprising 162 patients with CLNM and 214 patients without CLNM. The results of the multivariate logistic regression analysis revealed that age, Tg-Ab level, tumor size, punctate echogenic foci, and blood flow grade were identified as independent risk factors associated with the development of CLNM in HT PTC. The area under the curve (AUC) of this model was 0.76 (95% CI [0.71-0.80]). The sensitivity, specificity, accuracy, and positive predictive value of the model were determined to be 88%, 51%, 67%, and 57%, respectively. Conclusions: The proposed clinic-ultrasound-based nomogram in this study demonstrated a favorable performance in predicting CLNM in HT PTCs. This predictive tool has the potential to assist clinicians in making well-informed decisions regarding the appropriate extent of surgical intervention for patients.

CircPHGDH downregulation decreases papillary thyroid cancer progression through miR-122-5p/PKM2 axis.

BACKGROUND: Although papillary thyroid carcinoma (PTC) has a favorable prognosis, it could affect patient life quality and become a serious threat because of invasion and metastasis. Many investigations have suggested that circular RNAs (circRNAs) are involved in different cancer regulations. Nevertheless, circRNAs role in invasive PTC remains unclear. METHODS: In the present investigation, next-generation sequencing was applied to explore abnormal circRNA expression. The expression of circRNA phosphoglycerate dehydrogenase (circPHGDH) in PTC cell lines and tissues were examined. Then, we investigated regulatory mechanism and circPHGDH downstream targets using bioinformatics analysis and luciferase reporting analysis. Then transwell migration, Cell Counting Kit-8 (CCK8) and 5-ethynyl-2'-deoxyuridine (EdU) assays were used for cells migration and proliferation analysis. In vivo metastasis and tumorigenesis assays were also employed to evaluate the circPHGDH role in PTC. RESULTS: The data showcased that circPHGDH expression increased in both PTC cell lines and tissues, which suggested that circPHGDH functions in PTC progression. circPHGDH downregulation suppressed PTC invasion and proliferation in both in vivo and in vitro experiments. Bioinformatics and luciferase reporter results confirmed that both microRNA (miR)-122-5p and pyruvate kinase M2 subtype (PKM2) were downstream targets of circPHGDH. PKM2 overexpression or miR-122-5p suppression reversed PTC cell invasion and proliferation post silencing circPHGDH by restoring aerobic glycolysis. CONCLUSION: Taken together, our research found that circPHGDH downregulation reduced PTC progression via miR-122-5p/PKM2 axis regulation mediated by aerobic glycolysis.

Intraluminal extension of papillary thyroid carcinoma into the Internal Jugular Vein; a case report.

BACKGROUND: Papillary thyroid carcinoma (PTC), being the most common thyroid malignancy, is a slow-growing tumor and is usually limited to the thyroid. Extra thyroid extension is uncommon; besides, invasion to the vasculature seems to be extremely rare and usually indicates aggressive nature of the disease. CASE PRESENTATION: We present a case of a 40-year-old lady who referred with a palpable neck mass a month after total thyroidectomy which its histopathologic examination revealed follicular variant of PTC; the same variant as prior thyroidectomy. Preoperative ultrasonography failed to comment on the intravascular component of the mass. Surgical procedure confirmed a mass attaching and infiltrating to the internal jugular vein, which turned out to be persistent disease. CONCLUSIONS: Awareness of this entity is important for surgeons, oncologists and radiologist as it can influence patient management.

Case report: A rare combination of aldosterone-secreting adrenocortical carcinoma and papillary thyroid carcinoma with Graves' disease.

Adrenocortical carcinoma (ACC) is a rare malignancy originating in the adrenal glands, aldosterone-producing ACC, even rarer. Papillary thyroid carcinoma (PTC), by contrast, accounts for the majority of thyroid carcinomas. We herein describe the first reported case of a female with comorbidities of aldosterone-producing ACC, PTC, and Graves' Disease(GD). The patient achieved transient clinical remission following adrenalectomy. However, three months later, aldosterone-producing ACC lung metastases emerged. Subsequently, within another three-month interval, she developed thyroid eye disease(TED). The patient died roughly one year after the adrenal operation. Exome sequencing did not reveal associations between aldosterone-producing ACC, PTC, and GD, and the underlying concurrence mechanism has yet to be elucidated. Further research of similar cases are needed to confirm potential links between the three pathologies.

Dihydrotanshinone I exhibits antitumor effects via ß-catenin downregulation in papillary thyroid cancer cell lines.

Thyroid cancer is the most common endocrine carcinoma and, among its different subtypes, the papillary subtype (PTC) is the most frequent. Generally, PTCs are well differentiated, but a minor percentage of PTCs are characterized by a worse prognosis and more aggressive behavior. Phytochemicals, naturally found in plant products, represent a heterogeneous group of bioactive compounds that can interfere with cell proliferation and the regulation of the cell cycle, taking part in multiple signaling pathways that are often disrupted in tumor initiation, proliferation, and progression. In this work, we focused on 15,16-dihydrotanshinone I (DHT), a tanshinone isolated from Salvia miltiorrhiza Bunge (Danshen). We first evaluated DHT biological effect on PTC cells regarding cell viability, colony formation ability, and migration capacity. All of these parameters were downregulated by DHT treatment. We then investigated gene expression changes after DHT treatment by performing RNA-seq. The analysis revealed that DHT significantly reduced the Wnt signaling pathway, which plays a role in various diseases, including cancer. Finally, we demonstrate that DHT treatment decreases protein levels of ß-catenin, a final effector of canonical Wnt signaling pathway. Overall, our data suggest a possible use of this nutraceutical as an adjuvant in the treatment of aggressive papillary thyroid carcinoma.

lncRNA HCG22 regulated cell growth and metastasis of papillary thyroid cancer via negatively modulating miR-425-5p.

INTRODUCTION: Papillary thyroid cancer (PTC) is a common malignant tumour in the endocrine system with increasing incidence. LncRNA HCG22 (HCG22) was noticed to be dysregulated in PTC, but its specific function and mechanism remain unknown. The function of HCG22 and its underlying molecular mechanism was investigated to evaluate its potential as a biomarker for PTC. MATERIAL AND METHODS: The expression of HCG22 was detected in PTC cells (TPC-1, SNU790, GLAG-66, and BCPAP) and normal thyroid cells (Nthy-ori) using real time quantative polymerase chain reaction (RT-qPCR). HCG22 and miR-425-5p were regulated by cell transfection. The cell proliferation and metastasis were assessed by CCK8 and Transwell assay. RESULTS: HCG22 was upregulated in PTC cells, of which the knockdown suppressed the proliferation, migration, and invasion of PTC cells. miR-425-5p was downregulated in PTC cells, which was negatively regulated by HCG22. Silencing miR-425-5p could reverse the inhibitory effect of HCG22 knockdown on the cellular processes of PTC. CONCLUSIONS: HCG22 served as a tumour promoter in PTC cells, which regulated cell proliferation and metastasis via negatively regulating miR-425-5p.

Spatial transcriptomics reveals prognosis-associated cellular heterogeneity in the papillary thyroid carcinoma microenvironment.

BACKGROUND: Papillary thyroid carcinoma (PTC) is the most common malignant endocrine tumour, and its incidence and prevalence are increasing considerably. Cellular heterogeneity in the tumour microenvironment is important for PTC prognosis. Spatial transcriptomics is a powerful technique for cellular heterogeneity study. METHODS: In conjunction with a clinical pathologist identification method, spatial transcriptomics was employed to characterise the spatial location and RNA profiles of PTC-associated cells within the tissue sections. The spatial RNA-clinical signature genes for each cell type were extracted and applied to outlining the distribution regions of specific cells on the entire section. The cellular heterogeneity of each cell type was further revealed by ContourPlot analysis, monocle analysis, trajectory analysis, ligand-receptor analysis and Gene Ontology enrichment analysis. RESULTS: The spatial distribution region of tumour cells, typical and atypical follicular cells (FCs and AFCs) and immune cells were accurately and comprehensively identified in all five PTC tissue sections. AFCs were identified as a transitional state between FCs and tumour cells, exhibiting a higher resemblance to the latter. Three tumour foci were shared among all patients out of the 13 observed. Notably, tumour foci No. 2 displayed elevated expression levels of genes associated with lower relapse-free survival in PTC patients. We discovered key ligand-receptor interactions, including LAMB3-ITGA2, FN1-ITGA3 and FN1-SDC4, involved in the transition of PTC cells from FCs to AFCs and eventually to tumour cells. High expression of these patterns correlated with reduced relapse-free survival. In the tumour immune microenvironment, reduced interaction between myeloid-derived TGFB1 and TGFBR1 in tumour focus No. 2 contributed to tumourigenesis and increased heterogeneity. The spatial RNA-clinical analysis method developed here revealed prognosis-associated cellular heterogeneity in the PTC microenvironment. CONCLUSIONS: The occurrence of tumour foci No. 2 and three enhanced ligand-receptor interactions in the AFC area/tumour foci reduced the relapse-free survival of PTC patients, potentially leading to improved prognostic strategies and targeted therapies for PTC patients.

MYB/LINC00092 regulatory axis promotes the progression of papillary thyroid carcinoma.

INTRODUCTION: Thyroid carcinoma is the most frequent malignancy in different endocrine-related tumours. In this study, we demonstrated a long non-coding RNA LINC00092-associated molecular mechanism in promoting the progression of papillary thyroid carcinoma (PTC). MATERIAL AND METHODS: The expression of LINC00092 was analysed in the The Cancer Genome Atlas Thyroid Cancer (TCGA-THCA) patient cohorts and further determined by q-PCR. (3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide) (MTT) assay, and wound healing assay confirmed the function of LINC00092 in migration and proliferation. Q-ChIP validated the transcriptional target. Luciferase reporter assay validated the miRNA-mRNA target. RESULTS: The analysis in patient cohorts and in PTC TPC-1 cells showed that the expression of LINC00092 was repressed in thyroid carcinoma. In addition, the expression of LINC00092 was negatively associated with the advanced thyroid TNM stages. LINC00092 repressed epithelial-mesenchymal transition (EMT), migration, and proliferation of TPC-1 cells. Interestingly, we identified that MYB, a well-studied tumour promoter, is a transcription factor of LINC00092, thereby the expression of LINC00092 was directly repressed by MYB. Furthermore, miR-4741 was also validated as a direct target of MYB and was induced by MYB. Notably, LINC00092 was repressed by miR-4741 through the direct 3'-untranslational region (3'-UTR) target. Therefore, MYB induced EMT of TPC-1 cells by repressing LINC00092 directly or indirectly via miR-4741. CONCLUSIONS: Our study validated that LINC00092 is a tumour suppressor lncRNA in PTC. MYB directly or indirectly represses LINC00092, which contributes to the PTC progression. MYB, LINC00092, and miR-4741 form a coherent feed forward loop. The axis of MYB-LINC00092 promotes progression of PTC.

p53-associated miRNAs repress lncRNA ZFAS1 to retard the proliferation of papillary thyroid carcinoma.

INTRODUCTION: Thyroid carcinoma is the most frequent malignancy among endocrine-related tumours. Papillary thyroid carcinoma (PTC) is the main type of thyroid carcinoma, and almost 80% cases of thyroid carcinoma are diagnosed as PTC. The molecular mechanism underlying PTC progression is unclear. This study aims to investigate the potential mechanisms of zinc finger antisense 1 (ZFAS1) function in PTC. MATERIAL AND METHODS: The expression of ZFAS1 and p53 was determined by quantitative polymerase chain analysis (qPCR) in PTC tissues derived from 20 PTC patients. Quantitative chromatin immunoprecipitation assay (qChIP) analysis was performed to validate the target of ZFAS1/p53 and miRNAs/p53. The Gene Expression Omnibus (GEO) dataset GSE94908 was analysed to obtain the differentially expressed p53-associated microRNAs (miRNAs). Luciferase assay validated the target of ZFAS1/miRNAs, and 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to determine the cell proliferation. RESULTS: The expression of ZFAS1 was up-regulated in the tissues derived from PTC patients, and the expression of ZFAS1 was negatively associated with p53 expression in PTC. The expression of ZFAS1 was significantly higher in the MDA-T120 cells harbouring mutant p53. We validated that ZFAS1 is a direct target of p53. In PTC cells, p53 directly repressed the ZFAS1 expression. In addition, we determined that miR-135b-5p and miR-193a-3p are directly induced by p53 in PTC cells. Interestingly, p53-targeted miR-135b-5p, miR-193a-3p, and miR-34b repressed the expression of ZFAS1 via the seed-matching sequences in the 3'-untranslated region (3'-UTR) of ZFAS1, and thereby suppressed PTC cell proliferation induced by ZFAS1. CONCLUSION: The oncogenic lncRNA ZFAS1 is directly repressed by p53 in PTC. p53-mediated miRNAs including miR-135b 5p, miR-193a-3p, and miR-34b repress ZFAS1 expression, and thereby inhibit the proliferation of PTC.

Papillary thyroid carcinoma tall cell subtype (PTC-TC) and high-grade differentiated thyroid carcinoma tall cell phenotype (HGDTC-TC) have different clinical behaviour: a retrospective study of 1456 patients.

AIMS: Papillary thyroid carcinoma, tall cell subtype (PTC-TC) is a potentially aggressive histotype. The latest World Health Organisation (WHO) classification introduced a novel class of tumours; namely, high-grade differentiated thyroid carcinoma (HGDTC), characterised by elevated mitotic count and/or necrosis, which can exhibit a tall cell phenotype (HGDTC-TC). METHODS AND RESULTS: We analysed the clinical outcomes in a large retrospective cohort of 1456 consecutive thyroid carcinomas with a tall cell phenotype, including PTC-TC and HGDTC-TC. HGDTC-TC is uncommon, accounting for 5.3% (77 of 1379) of carcinomas with tall cell morphology. HGDTC-TC was associated with significantly older age, larger tumour size, angioinvasion, gross extrathyroidal extension, higher AJCC pT stage, positive resection margin and nodal metastasis (P < 0.05). Compared with PTC-TC, HGDTC was associated with a significantly decreased DSS, LRDFS and distant metastasis-free survival (DMFS; P < 0.001). The 10-year DSS was 72 and 99%, the 10-year LRDFS was 61 and 92% and the 10-year DMFS was 53 and 97%, respectively, for HGDTC-TC and PTC-TC. On multivariate analysis, the classification (HGDTC-TC versus PTC-TC) was an independent adverse prognostic factor for DSS, LRDF, and DMFS when adjusted for sex, age, angioinvasion, margin status, AJCC pT and pN stage. CONCLUSIONS: Compared with PTC-TC, HGDTC-TC is associated with adverse clinicopathological features, a higher frequency of TERT promoter mutations (59% in HGDTC-TC versus 34% in PTC-TC) and incurs a significantly worse prognosis. HGDTC-TC is an independent prognostic factor for carcinoma with tall cell morphology. This validates the concept of HGDTC and the importance of tumour necrosis and high mitotic count for accurate diagnosis and prognosis of differentiated thyroid carcinomas.

Circ-LDLRAD3/miR-655-3p/MAPK1 axis enhances cell migration and invasion in papillary thyroid carcinoma.

Papillary thyroid carcinoma (PTC) is a prevalent histological subtype of thyroid cancer, whose occurrence and development may be related to circRNA dysregulation. This research proposed to unravel circ-LDLRAD3-related mechanisms in PTC. First, circ-LDLRAD3, miR-655-3p .and MAPK1 levels in PTC were quantitatively measured. Then, plasmid vectors or oligonucleotides that interfere with circ-LDLRAD3, miR-655-3p, or MAPK1 were transfected into PTC cells, followed by the analysis of proliferation, apoptosis, migration, and invasion. Finally, the targeted binding sites between miR-655-3p and circ-LDLRAD3 or MAPK1 were predicted by starBase and experimentally verified. Statistically, PTC samples expressed high circ-LDLRAD3 and MAPK1 and low miR-655-3p. Knocking down circ-LDLRAD3 or enhancing miR-655-3p hindered PTC cell proliferation, migration, and invasion, and forced apoptosis. circ-LDLRAD3 bound to miR-655-3p to affect MAPK1 expression. Elevating MAPK1 rescued circ-LDLRAD3 knockdown-allowed obstruction of PTC cell growth. In conclusion, circ-LDLRAD3 stimulates PTC development by releasing miR-655-3p-targeted MAPK1.

A distinct tumor microenvironment makes anaplastic thyroid cancer more lethal but immunotherapy sensitive than papillary thyroid cancer.

Both anaplastic thyroid cancer (ATC) and papillary thyroid cancer (PTC) originate from thyroid follicular epithelial cells, but ATC has a significantly worse prognosis and shows resistance to conventional therapies. However, clinical trials found that immunotherapy works better in ATC than late-stage PTC. Here, we used single-cell RNA sequencing (scRNA-Seq) to generate a single-cell atlas of thyroid cancer. Differences in ATC and PTC tumor microenvironment components (including malignant cells, stromal cells, and immune cells) leading to the polarized prognoses were identified. Intriguingly, we found that CXCL13+ T lymphocytes were enriched in ATC samples and might promote the development of early tertiary lymphoid structure (TLS). Last, murine experiments and scRNA-Seq analysis of a treated patient's tumor demonstrated that famitinib plus anti-PD-1 antibody could advance TLS in thyroid cancer. We displayed the cellular landscape of ATC and PTC, finding that CXCL13+ T cells and early TLS might make ATC more sensitive to immunotherapy.

CircNRCAM up-regulates NRCAM to promote papillary thyroid carcinoma progression.

PURPOSE: Papillary Thyroid Carcinoma (PTC) is the most prevalent subtype of Thyroid Carcinoma (THCA), a type of malignancy in the endocrine system. According to prior studies, Neural Cell Adhesion Molecule (NRCAM) has been found to be up-regulated in PTC and stimulates the proliferation and migration of PTC cells. However, the specific mechanism of NRCAM in PTC cells is not yet fully understood. Consequently, this study aimed to investigate the underlying mechanism of NRCAM in PTC cells, the findings of which could provide new insights for the development of potential treatment targets for PTC. METHODS AND RESULTS: Bioinformatics tools were utilized and a series of experiments were conducted, including Western blot, colony formation, and dual-luciferase reporter assays. The data collected indicated that NRCAM was overexpressed in THCA tissues and PTC cells. Circular RNA NRCAM (circNRCAM) was found to be highly expressed in PTC cells and to positively regulate NRCAM expression. Through loss-of-function assays, both circNRCAM and NRCAM were shown to promote the proliferation, invasion, and migration of PTC cells. Mechanistically, this study confirmed that precursor microRNA-506 (pre-miR-506) could bind with m6A demethylase AlkB Homolog 5 (ALKBH5), leading to its m6A demethylation. It was also discovered that circNRCAM could competitively bind to ALKBH5, which restrained miR-506-3p expression and promoted NRCAM expression. CONCLUSION: In summary, circNRCAM could up-regulate NRCAM by down-regulating miR-506-3p, thereby enhancing the biological behaviors of PTC cells.

Chronic Lymphocytic Thyroiditis with Oncocytic Metaplasia Influences PD-L1 Expression in Papillary Thyroid Carcinoma.

BACKGROUND: Despite the increasing recognition of PD-L1 as predictor of immunotherapeutic response in various malignancies, its role and prognostic significance in thyroid cancer remain underexplored and subject to debate. This study begins to address this gap by comprehensively analyzing PD-L1 expression in papillary thyroid carcinoma (PTC) and investigating its correlation with key clinicopathological variables. METHODS: We conducted immunohistochemistry (IHC) to assess PD-L1 expression in whole-tissue sections from 121 primary papillary thyroid carcinoma (PTC) cases. We then analyzed the correlations between PD-L1 expression and various clinicopathological variables. RESULTS: PD-L1 expression was detected in 33.1% of papillary thyroid carcinomas (PTCs), predominantly exhibiting weak to moderate intensity. Notably, this study found no significant correlation between PD-L1 expression and various clinicopathological variables. The lack of association with traditional factors such as age, sex, histological subtype, and tumor size suggests the complex and multifaceted nature of PD-L1 regulation in PTC. Multivariate logistic regression analysis identified chronic lymphocytic thyroiditis with oncocytic metaplasia as the sole independent predictor of PD-L1 expression (P = 0.014), underlining the potential influence of the tumor microenvironment on immune checkpoint expression in PTC. CONCLUSIONS: Our study underscores the intricate interplay between chronic lymphocytic thyroiditis with oncocytic metaplasia and PD-L1 expression in papillary thyroid carcinoma. The observed link suggests a potential avenue for therapeutic intervention using anti-PD-1/PD-L1 therapies in surgery-refractory PTC. Understanding the dynamics of immune checkpoint regulation in the context of the tumor microenvironment is crucial for devising effective treatment strategies. Future research endeavors should delve deeper into the molecular mechanisms underlying this interaction and explore its implications for patient outcomes. As the field of immunotherapy continues to evolve, our findings contribute valuable insights into the complex immunological landscape of thyroid cancer.

Cytosolic Cadherin 4 promotes angiogenesis and metastasis in papillary thyroid cancer by suppressing the ubiquitination/degradation of ß-catenin.

BACKGROUND: Although the long-term prognosis of papillary thyroid cancer (PTC) is favorable, distant metastasis significantly compromises the prognosis and quality of life for patients with PTC. The Cadherin family plays a pivotal role in tumor metastasis; however, the involvement of Cadherin 4 (CDH4) in the metastatic cascade remains elusive. METHODS: The expression and subcellular localization of CDH4 were determined through immunohistochemistry, immunofluorescence, and western blot analyses. The impact of CDH4 on cell migration, invasion, angiogenesis, and metastasis was assessed using transwell assays, tube formation assays, and animal experiments. Immunoprecipitation assay and mass spectrometry were employed to examine protein associations. The influence of CDH4 on the subcellular expression of ß-catenin and active ß-catenin was investigated via western blotting and immunofluorescence. Protein stability and ubiquitination assay were employed to verify the impact of CDH4 on ß-catenin degradation. Rescue experiments were performed to ensure the significance of CDH4 in regulating nuclear ß-catenin signaling. RESULTS: CDH4 was found to be significantly overexpressed in PTC tissues and predominantly localized in the cytoplasm. Furthermore, the overexpression of CDH4 in tumor tissues is associated with lymph node metastasis in PTC patients. Cytosolic CDH4 promoted the migration, invasion, and lung metastasis of PTC cells and stimulated the angiogenesis and tumorigenesis of PTC; however, this effect could be reversed by Tegavivint, an antagonist of ß-catenin. Mechanistically, cytosolic CDH4 disrupted the interaction between ß-catenin and ß-TrCP1, consequently impeding the ubiquitination process of ß-catenin and activating the nuclear ß-catenin signaling. CONCLUSIONS: CDH4 induces PTC angiogenesis and metastasis via the inhibition of ß-TrCP1-dependent ubiquitination of ß-Catenin.

Active Surveillance for Low-Risk Papillary Thyroid Carcinoma as an Acceptable Management Option with Additional Benefits: A Comprehensive Systematic Review.

BACKGRUOUND: Active surveillance (AS) has been introduced as a management strategy for low-risk papillary thyroid carcinoma (PTC) due to its typically indolent nature. Despite this, the widespread adoption of AS has encountered several challenges. The aim of this systematic review was to evaluate the safety of AS related to disease progression and its benefits compared with immediate surgery (IS). METHODS: Studies related to AS in patients with low-risk PTC were searched through the Ovid MEDLINE, Embase, Cochrane Library, and KoreaMed databases. Studies on disease progression, surgical complication, quality of life (QoL), and cost-effectiveness were separately analyzed and narratively synthesized. RESULTS: In the evaluation of disease progression, the proportions of cases with tumor growth ≥3 mm and a volume increase >50% were 2.2%-10.8% and 16.0%-25.5%, respectively. Newly detected lymph node metastasis was identified in 0.0%-1.4% of patients. No significant difference was found between IS and delayed surgery in surgical complications, including vocal cord paralysis and postoperative hypoparathyroidism. AS was associated with better QoL than IS. Studies on the cost-effectiveness of AS reported inconsistent data, but AS was more cost-effective when quality-adjusted life years were considered. CONCLUSION: AS is an acceptable management option for patients with low-risk PTC based on the low rate of disease progression and the absence of an increased mortality risk. AS has additional benefits, including improved QoL and greater QoL-based cost-effectiveness.