Background: Although the pathogenetic mechanisms of Hashimoto’s thyroiditis (HT) and Graves’ disease (GD) have been elucidated, the molecular mechanisms by which the abnormal immune function of cellular subpopulations trigger an autoimmune attack on thyroid tissue largely remains unexplained.Methods: The study included 2 HT patients, 2 GD patients, and 1 control donor. The thyroid samples were extracted for single-cell RNA sequencing, whole transcriptome, full-length transcriptome (Oxford Nanopore Technologies), and metabolome sequencing. Identification of immune cells with dysregulated gene expression and abnormal metabolic signaling was performed in the microenvironment, both at the bulk and single-cell levels. Based on functional enrichment analysis, the biological processes and pathways involved in abnormal immune cells were further explored. Finally, according to cell communication analysis, the global regulatory network of immune cells was constructed.Results: CD4⁺ T cells, CD8⁺ T cells, and macrophages were abnormally increased in patients with HT and GD. The differentially expressed genes of these cells were significantly involved in signaling pathways, including Th1 and Th2 cell differentiation, Th17 cell differentiation, cytokine–cytokine receptor interaction, and NF-kappa B signaling pathway. Moreover, in HT, CD4⁺ T cells interact with macrophages via the IL16-CCR5/FGF10-FGFR1/CXCL13-CXCR3 axis, and macrophages interact with CD8⁺ T cells via the CD70-CD27 axis, thereby activating the T-cell receptor signaling pathway and NF-kappa B signaling pathway. In GD, CD4⁺ T cells interact with macrophages via the CXCR3-CXCL10/PKM-CD44/MHCII-NFKBIE axis, and macrophages interact with CD8⁺ T cells via the IFNG-IFNGR1/CCR7-CCL21 axis, thereby activating T-cell receptor signaling pathway, Th1 and Th2 cell differentiation, and chemokine signaling pathway.Conclusion: In HT and GD, immune dysregulated cells interact and activate relevant immune pathways and further aggravate the immune response. This may trigger the immune cells to target the thyroid tissue and influence the development of the disease.

Both environmental and genetic factors contribute to the etiology of autoimmune thyroid disease (AITD) including Graves' disease (GD) and Hashimoto's thyroiditis (HT). However, the exact pathogenesis and interactions that occur between environmental factors and genes remain unclear, and therapeutic targets require further investigation due to limited therapeutic options. To solve such problems, this study utilized single-cell transcriptome, whole transcriptome, full-length transcriptome (Oxford nanopore technology), and metabolome sequencing to examine thyroid lesion tissues from 2 HT patients and 2 GD patients as well as healthy thyroid tissue from 1 control subject. HT patients had increased ATF4-positive thyroid follicular epithelial (ThyFoEp) cells, which significantly increased endoplasmic reticulum stress. The enhanced sustained stress resulted in cell death mainly including apoptosis and necroptosis. The ATF4-based global gene regulatory network and experimental validation revealed that N⁶-methyladenosine (m⁶A) reader hnRNPC promoted the transcriptional activity, synthesis, and translation of ATF4 through mediating m⁶A modification of ATF4. Increased ATF4 expression initiated endoplasmic reticulum stress signaling, which when sustained, caused apoptosis and necroptosis in ThyFoEp cells, and mediated HT development. Targeting hnRNPC and ATF4 notably decreased ThyFoEp cell death, thus ameliorating disease progression. Collectively, this study reveals the mechanisms by which microenvironmental cells in HT and GD patients trigger and amplify the thyroid autoimmune cascade response. Furthermore, we identify new therapeutic targets for the treatment of autoimmune thyroid disease, hoping to provide a potential way for targeted therapy.

Background: Hashimoto's thyroiditis (HT) is the most common organ‐specific autoimmune disease, and its etiology may be related to genetic, environmental, and epigenetic factors. However, its exact pathogenesis remains elusive.Methods: In this study, single‐cell transcriptomic sequencing and bioinformatics analysis were performed on the thyroid tissues of six HT patients, peripheral blood mononuclear cells (PBMCs) of four HT patients, and normal thyroid tissue of one healthy control. A panoramic single‐cell atlas of HT was constructed to explore changes in the abundance of different cell subsets in the states of the disease.Results: A single‐cell atlas of HT was constructed, and eight cell types were defined based on the marker genes. Subsequent clustering analysis of T cells, B cells, myeloid, and thyroid follicular cells revealed that the abundance rates of the CD8⁺T_CCL4L2, B_MEF2B_BCL6, Mac_APOE, Mac_IL1B, and TFC_PAX8_NKX2‐1 subgroups were elevated in thyroid tissues of HT patients. However, the abundance rate of the NKT_KLRD1_KLRC2 subgroup was risen in the PBMCs of HT patients. Ig‐producing plasma cells were specifically enriched in the B‐cell subgroup.Conclusion: The present study further validated the role of immune cells in the pathogenesis of HT at the cellular level. In addition, a new cell subset B_MEF2B_BCL6 was found. It could be speculated that MEF2B mainly transactivates the expression level of the transcriptional repressor BCL6, leading to the development of HT. A new cell subset TFC_PAX8_NKX2‐1 was also identified, in which the specific transcription factors PAX8 and NKX2‐1 were highly expressed in HT tissues.

Organoids are three-dimensional cellular aggregates derived from stem cells or primary tissues that can self-organize into organotypic structures and showcase the physiological functions of that organ. Organoids typically comprise multiple organ-specific cell types that are responsible for organ function in vivo. They may also incorporate various cellular and molecular stromal components to recapitulate the in vivo microenvironment of the target organ. All articles related to thyroid-like organs were synthesized. Articles published between 1959 and 2023 were assessed, categorized, and analyzed using relevant keywords. As such, organoids provide a model of greater physiological relevance than 2D cell culture for basic and translational research. Murine and human organoids of the thyroid have been established from embryonic stem cells (ESCs), pluripotent stem cells (PSCs) and from various healthy or diseased thyroid tissues. These thyroid organoids have been used in basic and translation research on thyroid-related diseases including hyperthyroidism, Graves' disease, and Hashimoto's thyroiditis. In addition, organoids derived from patients with thyroid cancer retain histopathological features and mutational profile of the original tumor. These patient-derived organoids have been successfully used in in vitro evaluation of drug response of individual patients, demonstrating their potential application in personalized treatment of thyroid cancer. In this review article, we have discussed various techniques for establishing thyroid organoids and their applications in thyroid-related diseases as disease models, regenerative medicines, or a tool for drug testing.

Anaplastic thyroid cancer (ATC) and papillary thyroid carcinoma (PTC) exhibit significant differences in clinical behavior and immune microenvironments, particularly concerning the mechanisms underlying CD8⁺ T cell dysfunction. However, these specific mechanisms have yet to be thorThe original blots and abbreviations are presented in Supplemeoughly investigated. The present study utilized single-cell RNA sequencing (scRNA-seq) data to conduct a comprehensive analysis of CD8⁺ T cells in the thyroid tissues of patients diagnosed with ATC and PTC. The results of the study indicate that CD8⁺ T cells in ATC display disruptions in energy supply and marked signs of exhaustion. Conversely, CD8⁺ T cells in PTC are more prone to maintaining a stable expression of immunosuppression-related membrane proteins through posttranslational modifications. This study highlights the distinct mechanisms of CD8⁺ T cell exhaustion in two types of thyroid cancer, offering valuable insights into the regulation of their immune microenvironments.

Introduction: Differentiated thyroid cancer generally has a favorable prognosis; however, the cure rate remains low for patients with metastatic or undifferentiated thyroid cancer. Moreover, this group of patients exhibits diverse responses to different treatments. To address this, single- cell RNA sequencing (scRNA-seq) offers an unbiased approach to reveal the heterogeneity within and between tumor cells. Using, scRNA-seq, we aimed to explore the intricate ecosystem of thyroid cancer, potentially providing novel insights into clinical cancer staging and treatment strategies. Methods: We conducted a thorough analysis by screening thyroid cancer and paraneoplastic tissues from 20 patients sourced from the Gene Expression Omnibus database. The dataset comprised 11 primary tumor tissues, 6 paraneoplastic tissues, 8 metastatic lymph nodes, and 2 distant metastases of papillary thyroid cancer. Through comprehensive bioinformatic analyses, we constructed a panoramic single-cell atlas of thyroid cancer (THCA). Results: Our findings revealed significant heterogeneity in gene expression among tumor cells from different patients with THCA, contributing to the development of a comprehensive single-- cell landscape. Notably, the long noncoding RNA (lncRNA) gene XIST exhibited higher abundance in anaplastic thyroid cancer (ATC) tumor cells. Additionally, we identified an enriched m6A locus in lncRNA XIST and observed high expression of the m6A "reader" IGF2BP3, as well as low expression of the "encoder" VIRMA. Based on these observations, we hypothesized that IGF2BP3 and VIRMA could augment the expression of lncRNA XIST, thereby promoting the malignant proliferation and invasion of ATC. Conclusion: By leveraging scRNA-seq technology, our study sheds light on the intricate molecular characteristics of THCA lesions. These findings have the potential to revolutionize our understanding of thyroid cancer pathogenesis and pave the way for innovative therapeutic interventions.