Follicular Epithelial Cells Research Articles

Derivation of transplantable human thyroid follicular epithelial cells from induced pluripotent stem cells.

The production of mature functioning thyroid follicular cells (TFCs) from human induced pluripotent stem cells (iPSCs) is critical for potential novel therapeutic approaches to post-surgical and congenital hypothyroidism. To accomplish this, we developed a novel human iPSC line that expresses fluorophores targeted to the NKX2-1 and PAX8 loci, allowing for the identification and purification of cells destined to become TFCs. Optimizing a sequence of defined, serum-free media to promote stepwise developmental directed differentiation, we found that bone morphogenic protein 4 (BMP4) and fibroblast growth factor 2 (FGF2) stimulated lineage specification into TFCs from multiple iPSC lines. Single-cell RNA sequencing demonstrated that BMP4 withdrawal after lineage specification promoted TFC maturation, with mature TFCs representing the majority of cells present within 1month. After xenotransplantation into athyreotic immunodeficient mice, engrafted cells exhibited thyroid follicular organization with thyroglobulin protein detected in the lumens of NKX2-1-positive follicles. While our iPSC-derived TFCs presented durable expression of thyroid-specific proteins, they were unable to rescue hypothyroidism invivo.

Proangiogenic effect of thyrotropin receptor stimulating antibody in human umbilical vein endothelial cells.

This study aims to investigate the role of TRAb in the angiogenesis associated with Graves' disease (GD) and to elucidate its underlying mechanisms. Human thyroid follicular epithelial cells (Nthy-ori 3-1) and human umbilical vein endothelial cells (HUVECs) were treated with the monoclonal thyroid-stimulating antibody M22 and thyroid-stimulating hormone (TSH) at various concentrations. Cell viability, migration, and tube formation were evaluated using CCK-8, wound healing, and tube formation assays, respectively. Protein expressions of TSHR receptor (TSHR) and phosphorylated AKT (p-AKT) in M22-induced HUVECs were quantified via Western blotting. Proteomic analysis was employed to identify changes in protein expression profiles and relevant signaling pathways in GD specimens. Immunofluorescence assays were conducted to detect and localize the expressions of CD34 and PROX1 in GD specimens and normal thyroid tissues. M22 stimulated the proliferation of Nthy-ori 3-1 cells and HUVECs in a dose-dependent manner, while TSH exhibited an inverted U-shaped dose-response effect. M22 also dose-dependently promoted angiogenesis, and more effectively induced tube formation in HUVECs compared to TSH, although the difference was not statistically significant. A total of 16 proteins were significantly upregulated and 24 were downregulated in M22-induced HUVECs. Notably, PROX1, the most significantly upregulated protein, is closely associated with angiogenesis. Immunofluorescence confirmed that PROX1 was significantly more expressed in thyroid tissues from GD patients compared to normal tissues adjacent to papillary thyroid cancer (PTC), and it co-localized with CD34. TRAb enhances angiogenesis and upregulates PROX1 expression in HUVECs, suggesting a novel possible mechanism for goiter formation in GD.

Jiajiejian gel ameliorates thyroid nodules through regulation of thyroid hormones and suppression of the (IL-6, TNF-α, IL-1β)/JAK2/STAT3/VEGF pathway.

The high incidence of thyroid nodules and their rapid growth in recent years have become an important issue affecting public health. Traditional Chinese medicine (TCM) external treatments have unique advantages in treating this disease, but the currently available external preparations are relatively few and the therapeutic mechanism is unclear. Jiajiejian gel (JJJG) is a TCM external preparation developed by our team for the thyroid nodule treatment, which has been preliminarily proven to be safe and effective in clinical practice. The current study was aimed to elucidate the therapeutic effects and the underlying mechanisms of JJJG on thyroid nodules in rats. The contents of paeonol and forsythoside A in JJJG were determined by HPLC. The thyroid nodules rat model was established through oral gavage of 0.1% propylthiouracil (PTU) for 6weeks and meanwhile the rats were treated with external JJJG (0.26, 0.52, 1.04g/kg). Subsequently, the therapeutic effect of JJJG was observed by means of ultrasonic examination, morphology observation, organ coefficients determination and histopathological analysis. Mechanismlly, the levels of FT3, FT4 and TSH in serum were measured and transcriptomics methods were used to analyse and screen the key targets and pathways of alleviating thyroid nodules by JJJG. Further, gene and protein expression levels of key factors in the pathways were measured and validated using quantitative real-time PCR, ELISA, western blotting and immunofluorescence, so as to clarify the therapeutic mechanism. The contents of the paeonol and forsythoside A were 1.160 and 0.608mg/g, respectively. JJJG reduced thyroid swelling, improved nodular lesions, decreased thyroid coefficients, and inhibited abnormal nodular hyperplasia of follicular epithelial cells. In terms of mechanism, JJJG significantly increased the levels of FT3 and FT4 and decreased TSH level in serum (P < 0.05). Transcriptomics suggested that the (IL-6, TNF-α, IL-1β)/JAK2/STAT3/VEGF pathway may be one of the key mechanisms in the treatment of thyroid nodules by JJJG. Further validation experiments demonstrated that JJJG significantly reduced the mRNA expression and protein content of IL-1β, IL-6 and TNF-α in thyroid tissue, as well as the mRNA expression of JAK2, STAT3 and VEGF and the protein expression of p-JAK2/JAK2, p-STAT3/STAT3 and VEGF (P < 0.05). This study indicates that JJJG efficiently ameliorates thyroid nodules by regulating the levels of FT3, FT4 and TSH in serum and suppressing (IL-6, TNF-α, IL-1β)/JAK2/STAT3/VEGF pathway in thyroid tissue, providing a potential therapeutic approach for thyroid nodules.

Haizao–Gancao herb pair ameliorates propylthiouracil-induced goiter by regulating the Beclin1-mediated autophagy

Ethnopharmacological relevanceHaizao, Sargassum, is widely used to treat goiter. Gancao, Glycyrrhizae radix et rhizome, is renowned for reducing toxicity or increasing effects in traditional Chinese medicine. As a classic herb pair, Haizao–Gancao (HG) is a commonly used and effective combined therapy for goiter. The underlying biological mechanisms of HG on goiter is still unclear. Aim of the studyTo explore the effect of HG on goiter, employing molecular docking combined with experimental validation to elucidate the molecular mechanism. Materials and methodsThe rat goiter model was created by gavageing propylthiouracil (PTU) intragastrically for a duration of 14 days. The rats had been separated into six groups: control, model, euthyrox, HG high-dose (HG-H), medium-dose (HG-M) and low-dose (HG-L) group. Based on general observations (such as the rats' living status, body weight, and rectal temperature), the relative weight of the thyroid, thyroid function, hematoxylin-eosin (HE) staining, and transmission electron microscopy (TEM) to view the pathological variations of the thyroid glands, the effect of HG was evaluated. Discovered the chemical composition of HG by UPLC-MS/MS and the possible targets were predicted adopting several databases. Next, we explored their pharmacological mechanisms using molecular docking and validated key targets using western blotting (WB) and co-immunoprecipitation (Co-IP). ResultsHG significantly increased the levels of triiodothyronine(T3), free triiodothyronine (FT3), free thyroxine (FT4), gained body weight and reduced tumescent thyroid glands in PTU-induced rats. The model group pathological changes such as uneven size, irregular shape and disordered arrangement of follicular epithelial cells occurred. However, HG groups thyroid follicles and epithelial cells appeared apparently normal. A variety of characteristic changes of autophagic vesicles appeared in the HG groups as opposed to the model group. In conclusion, the HG-L showed the best therapeutic effect. By UPLC-MS/MS, the major chemical components of HG were identified. The result revealed that HG contained flavonoids, alkaloids, organic acids, phenolic acidsand and terpenoids, etc. The molecular docking results of formononetin and naringenin and Beclin1 protein showed a high interaction of −5.38 kcal/mol and −5.25 kcal/mol. This implies that formononetin and naringenin may have a therapeutic effect in goiter rats by controlling the Beclin1-mediated autophagy. Western Blot (WB) and co-immunoprecipitation (Co-IP) results showed that HG can disrupt Beclin1/class III phosphatidylinositol 3-kinase(PI3KC3) binding and promote Beclin1/B-cell leukemia/lymphoma-2(Bcl-2) complex formation. Taken together, results demonstrate that autophagy inhibition via reducing Beclin1/PI3KC3 formation and increasing Beclin1/Bcl-2 binding activity. ConclusionsHG ameliorates propylthiouracil-induced goiter by regulating the Beclin1-mediated autophagy, thus promoting the autophagy of thyroid cells.

6847 Poorly Differentiated Thyroid Cancer: A Rare Entity

Abstract Disclosure: S. Fatima: None. S. Ward: None. A. Champion: None. Introduction: Poorly differentiated thyroid carcinoma (PDTC) is a rare thyroid carcinoma originating from follicular epithelial cells. Regarding the degree of differentiation, PDTC ranks between differentiated thyroid cancer and anaplastic thyroid cancer. We hereby present a rare case of PDTC. Case: 29-year-old female with a history of metastatic papillary thyroid cancer (PTC) presented to the emergency department with shortness of breath. She initially noticed a left thyroid mass in 2021. CT neck in 1/2022 showed a 7 cm left thyroid mass with substernal extension, small right thyroid mass with tracheal compression, left bulky cystic nodal masses extending anterior and posterior to carotid and internal jugular vein. PET scan in 3/2022 showed left 7.6 cm thyroid mass SUV 12.1 with tracheal compression, left level II-IV adenopathy with level IV nodal masses 5.1 cm SUV 4.5. Ultrasound-guided FNA in 4/2022 showed PTC in left 8.7cm thyroid nodule; right 2.8 cm nodule showed Atypia of Undetermined Significance; Left 5.5 cm neck level III lymph node (LN) showed PTC metastasis; right 5.1 cm neck level III LN showed PTC metastasis (+ thyroglobulin and TTF-1). CT chest in 11/2022 showed additional involvement of manubrium. Repeat core needle biopsy of left thyroid mass showed left invasive thyroid carcinoma. She was started on neoadjuvant Lenvatinib in 1/2023. Follow-up CT neck in 5/2023 showed a reduction in the size of the left thyroid mass to 5.5cm x 5.8cm x 6.5cm. At this time, she had symptoms of dysphagia, orthopnea, weight loss of about 60 lbs and neck pain. In 11/2023 at time of current presentation she underwent total thyroidectomy, bilateral modified radical neck dissection and manubriectomy. Surgical pathology showed PDTC in left thyroid mass, PTC in right thyroid mass with metastatic PDTC in left proximal sternocleidomastoid, manubrium and LN involvement in neck and mediastinum. OmniSeq Insight testing showed APC and BRCA1 gene mutations, negative BRAF V600E, RET fusion, RET mutation, NTRK1/2/3 fusion and PD L1 immunohistochemistry score is &amp;lt;1%. The patient is planned to receive [1]3[1]I ablation therapy. Conclusion: PDTC accounts for 3–5% of all thyroid carcinomas. The 5, 10-, and 15-year survival rates of patients are 50–85%, 34–50%, and 0%, respectively. RAS gene alterations are found in 25–35%, BRAF mutation in 15–27%, TERT promoter mutation in 40% and mutant TP53 in 16–28% of PDTCs. TERT promoter gene and TP53 mutation usually indicate an aggressive phenotype and a dismal prognosis. Surgery, [1]3[1]I therapy, and external beam radiotherapy constitute the mainstay of traditional treatment for patients with advanced disease; however, treatment is challenging. Tyrosine kinase inhibitors i.e, sorafenib and lenvatinib, have been used in cases of progressive, recurrent, or metastatic disease not responsive to [1]3[1]I therapy. Immunotherapy may be an option in PD-L1-positive tumors. Presentation: 6/1/2024

Papillary microcarcinoma in three generations of the first degree relatives

Family papillary microcarcinoma of the thyroid gland is observed in 3–10 % of patients with cancer from follicular epithelial cells. Diagnosis and treatment are controversial. Three patients from the same family of the first degree of kinship were operated for family papillary microcarcinoma of the thyroid gland in Voronezh Regional Clinical Hospital No. 1. Only the first patient complained of the neck deformity, her son and granddaughter had an asymptomatic course of the disease. Metastases to the lymph nodes of the neck and bilateral localization of the tumor were not revealed. In the third generation, multifocal tumor growth was diagnosed at the age of 19. All patients underwent thyroidectomy. In the first patient, the period of relapse–free follow-up after surgery was 18 years, in the second and third – 5 years. In the family form of papillary thyroid carcinoma, we consider active screening of relatives justified since the disease in the new generation may develop at a younger age and with the risk of multifocal thyroid damage even in microcarcinomas.

Coexistence of papillary thyroid carcinoma and sarcoidosis: a case report and literature review.

Papillary thyroid carcinoma is a differentiated thyroid cancer that arises from thyroid follicular epithelial cells. Sarcoidosis is a multisystem disease of unknown cause, characterized by monocytic infiltration and granuloma formation. We herein report a case of thyroid carcinoma complicated by sarcoidosis. When thyroid nodules and lymph node lesions are suspected, it is essential to avoid fixed thinking, conduct a comprehensive preoperative evaluation, and select the appropriate surgical approach. This can help reduce the likelihood of postoperative complications and improve the patient's quality of life. Therefore, comprehensive diagnosis of the coexistence of papillary thyroid carcinoma and sarcoidosis is crucial.

Suppression of Hippocampal Neurogenesis and Oligodendrocyte Maturation Similar to Developmental Hypothyroidism by Maternal Exposure of Rats to Ammonium Perchlorate, a Gunpowder Raw Material and Known Environmental Contaminant.

The environmental contaminant perchlorate raises concern for hypothyroidism-related brain disorders in children. This study investigated the effects of developmental perchlorate exposure on hippocampal neurogenesis and oligodendrocyte (OL) development. Pregnant Sprague-Dawley rats were administered with ammonium perchlorate (AP) in drinking water at concentrations of 0 (control), 300, and 1000 ppm from gestation day 6 until weaning [postnatal day (PND) 21]. On PND 21, offspring displayed decreased serum triiodothyronine and thyroxine concentrations at 1000 ppm and thyroid follicular epithelial cell hyperplasia at ≥300 ppm (accompanying increased proliferation activity at 1000 ppm). Hippocampal neurogenesis indicated suppressed proliferation of neurogenic cells at ≥300 ppm, causing decreases in type-1 neural stem cells (NSCs) and type-2a neural progenitor cells. In addition, an increase of SST+ GABAergic interneurons and decreasing trend for ARC+ granule cells were observed at 1000 ppm. CNPase+ mature OLs were decreased in number in the dentate gyrus hilus at ≥300 ppm. At PND 77, thyroid changes had disappeared; however, the decrease of type-1 NSCs and increase of SST+ interneurons persisted, CCK+ interneurons were increased, and white matter tissue area was decreased at 1000 ppm. Obtained results suggest an induction of hypothyroidism causing suppressed hippocampal neurogenesis (targeting early neurogenic processes and decreased synaptic plasticity of granule cells involving ameliorative interneuron responses) and suppressed OL maturation during the weaning period. In adulthood, suppression of neurogenesis continued, and white matter hypoplasia was evident. Observed brain changes were similar to those caused by developmental hypothyroidism, suggesting that AP-induced developmental neurotoxicity was due to hypothyroidism.

No Correlation between PD-L1 and NIS Expression in Lymph Node Metastatic Papillary Thyroid Carcinoma.

Approximately 90% of thyroid cancers are differentiated thyroid cancers (DTCs), originating from follicular epithelial cells. Out of these, 90% are papillary thyroid cancer (PTC), and 10% are follicular thyroid cancer (FTC). The standard care procedure for PTC includes surgery, followed by radioiodine (RAI) ablation and thyroid-stimulating hormone (TSH) suppressive therapy. Globally, treating radioiodine-refractory DTC poses a challenge. During malignant transformation, thyroid epithelial cells often lose their ability to absorb radioiodine due to impaired membrane targeting or lack of NIS (sodium/iodide symporter) expression. Recent reports show an increase in PD-L1 (programmed death ligand 1) expression in thyroid cancer cells during dedifferentiation. However, no research exists wherein NIS and PD-L1 expression are analyzed together in thyroid cancer. Therefore, we aimed to investigate and correlate PD-L1 and NIS expression within primary tumor samples of lymph node metastatic PTC. We analyzed the expression of hNIS (human sodium/iodide symporter) and PD-L1 in primary tumor samples from metastatic PTC patients using immunohistochemistry. Immunohistochemistry analysis of PD-L1 and NIS was conducted in 89 and 86 PTC cases, respectively. Any subcellular NIS localization was counted as a positive result. PD-L1 expression was absent in 25 tumors, while 58 tumors displayed PD-L1 expression in 1-50% of their cells; in 6 tumors, over 50% of the cells tested positive for PD-L1. NIS immunohistochemistry was performed for 86 primary papillary carcinomas, with 51 out of 86 tumors showcasing NIS expression. Only in seven cases was NIS localized in the plasma membrane; in most tumors, NIS was primarily found in the intracytoplasmic membrane compartments. In the case of PD-L1 staining, cells showing linear membrane positivity of any intensity were counted as positive. The evaluation of NIS immunostaining was simpler: cells showing staining of any intensity of cytoplasmic or membranous fashion were counted as positive. The number of NIS positive cells can be further divided into cytoplasmic and membrane positive compartments. There was no observed correlation between PD-L1 and NIS expression. We can speculate that the manipulation of the PD-1/PD-L1 axis using anti-PD-L1 or anti-PD-1 antibodies could reinstate the functional expression of NIS. However, based on our study, the only conclusion that can be drawn is that there is no correlation between the percentage of NIS- or PD-L1-expressing tumor cells in the primary tumor of lymph node metastatic PTC.

Histopathological and Immunohistochemical Studies on Endocrine Glands of Dogs with Special Emphasis on the Immunoexpression of β-cells of the Pancreas

The aim of this study to evaluate the histopathological, histochemical and immunohistochemical changes of the endocrine glands namely, thyroid, pancreas and adrenal gland in dogs submitted to routine necropsy. A total number of 45 endocrine samples were collected from 15 carcasses of dogs received at Department of Veterinary Pathology, Madras Veterinary College, Chennai- 600 007 were chosen for the present study, namely thyroid, pancreas and adrenal gland. The tissue samples were collected in 10% neutral buffered formalin. Tissues were processed after 48 hours as per recommended procedure and 3 µm thickness sections were made and stained with haematoxylin and eosin for histopathological evaluation. The special stains like Masson’s trichrome and Picrosirius red were used to assess the extent of replacement with collagen fibers. Immunohistochmical protocol was followed as per the manufactured recommendation (Pathnsitu, USA).The histopathological changes recorded in the pancreas included vacuolar changes (2/15), necrosis (2/15), periductular fibrosis (1/15), perivascular fibrosis (1/15), congestion (5/15), hemorrhages (3/15) and inflammatory changes (1/15) while in the adrenal glands included diffuse cortical hyperplasia (4/15) succeeded by nodular hyperplasia (3/15), adrenalitis (2/15), hyperaemia (2/15), hemorrhages (1/15) and atrophy (1/15). Histopathological examination of thyroid revealed atrophy of follicles suggesting thyroiditis (3/15), presence of follicular epithelial cells which were found separated from the basement membrane with cellular debris in the lumen indicating necrosis (2/15) and presence of large cystic gaps with eosinophilic proteinaceous material consistent with cystadenoma(2/15). The remaining samples showed hemorrhages (2/15), perivascular fibrosis (1/15) and congestion (2/15). However no histological alterations were noticed in 3 cases (3/15). Immunohistochemistry revealed that pancytokeratin was expressed by all epithelial cells including ducts. The expression of insulin was noticed in all the cases indicating that no reduction of â cells in all the above said pathological conditions.

Titanium dioxide nanoparticles Disrupt ultrastructure and function of Rat thyroid tissue via oxidative stress

Nano-TiO2 is widely used in various fields such as industry, daily necessities, food and medicine. Previous studies have shown that it can enter mammalian tissues through the digestive tract or respiratory tract and have effects on various organs and systems. However, the effect of nano-TiO2 on the mammalian thyroid gland has not been reported. In this study, we fed SD rats with rutile nano-TiO2 at a dose of 5 mg/kg body weight for 3 weeks, and then examined the thyroid histology and thyroid function of the rats. In vitro experiments were conducted to determine the effects of nano-TiO2 on the viability, apoptosis, inflammatory factors, antioxidant enzymes, and oxidative stress of human thyroid follicular epithelial cells. Histological evidence showed abnormal morphology of rat thyroid follicles and organelle damage in follicular epithelial cells. Nano-TiO2 caused a decrease in the level of sodium/iodide symporter (NIS), an increase in the level of apoptotic protein cleaved-caspase 3, and an increase in the levels of pro-inflammatory factors IL-1β and TNF-α in rat thyroid tissue. Nano-TiO2 also resulted in increased serum FT4 and TPO-Ab levels. In in vitro experiments, nano-TiO2 reduced the viability of human thyroid follicular cells, downregulated the levels and activities of antioxidant enzymes CAT, GPX1 and SOD, and increased the levels of ROS and MDA caused by oxidative stress. These results indicate that nano-TiO2 damages the structure and function of thyroid follicular epithelial cells through oxidative stress. Long-term exposure to nano-TiO2 could be a potential risk factor for thyroid dysfunction.

Effect of progestin on thyroid function in female Wistar rats.

To characterize the influence of female-specific hormones on women's thyroid function, the study investigated the influence of extra progestin from oral contraceptives on inducing thyroid dysfunction. Sixty female Wistar rats were divided into six groups based on levonorgestrel or desogestrel administration as the main active agents: control, low (0.0039 mg*20-fold), medium (0.0039 mg*100-fold), high (0.0318 mg*100-fold) levonorgestrel (pure product); and low (0.0083 mg*20-fold) and high (0.0083 mg*100-fold) desogestrel (pure product). Progestin was administered by gavage every 4 days for 1 month. Statistical analysis was performed using one-way analysis of variance and the Kruskal-Wallis test. Following levonorgestrel gavage, serum free T4 and thyroidstimulating hormone levels were significantly lower in the experimental group than that in the control group (p=0.013 and 0.043). After desogestrel gavage, the serum free T4 and free T3 levels were lower in the experimental group than that in the control group (p=0.019 and 0.030). Thyroid hormone antibody concentrations were lower in rats administered levonorgestrel and desogestrel than that in control rats. Moreover, exposure to progestin upregulated the expression of the thyroid-stimulating hormone receptor and sodium iodide symporter in thyroid. Progestin stimulation enhanced the proliferation of follicular epithelial cells in rat thyroid tissues. Progestin exposure could cause thyroid dysfunction by upregulating the transcription of thyroid-stimulating hormone receptor and sodium iodide symporter in thyroid, thus inducing pathomorphological changes in rats' thyroid.

Transcriptomic characterization of single cells derived from immortalized human thyroid follicular epithelial cell lines

Transcriptomic characterization of single cells derived from immortalized human thyroid follicular epithelial cell lines

RNA Interference-Mediated Suppression of Ecdysone Signaling Inhibits Choriogenesis in Two Coleoptera Species.

During choriogenesis in insects, chorion (eggshell) is formed by surrounding follicular epithelial cells in ovarioles. However, the regulatory endocrine factor(s) activating choriogenesis and the effect of chemical components on eggshell deserve further exploration. In two representative coleopterans, a coccinellid Henosepilachna vigintioctopunctata and a chrysomelid Leptinotarsa decemlineata, genes encoding the 20-hydroxyecdysone (20E) receptor heterodimer, ecdysone receptor (EcR) and ultraspiracle (USP), and two chitin biosynthesis enzymes UDP-N-acetylglucosamine pyrophosphorylase (UAP) and chitin synthase (ChS1), were highly expressed in ovaries of the young females. RNA interference (RNAi)-aided knockdown of either HvEcR or Hvusp in H. vigintioctopunctata inhibited oviposition, suppressed the expression of HvChS1, and lessened the positive signal of Calcofluor staining on the chorions, which suggests the reduction of a chitin-like substance (CLS) deposited on eggshells. Similarly, RNAi of LdEcR or Ldusp in L. decemlineata constrained oviposition, decreased the expression of LdUAP1 and LdChS1, and reduced CLS contents in the resultant ovaries. Knockdown of LdUAP1 or LdChS1 caused similar defective phenotypes, i.e., reduced oviposition and CLS contents in the L. decemlineata ovaries. These results, for the first time, indicate that 20E signaling activates choriogenesis in two coleopteran species. Moreover, our findings suggest the deposition of a CLS on the chorions.

Decabromodiphenyl ether exposure reduces dabrafenib sensitivity of papillary thyroid carcinoma harboring BRAFV600E mutation through the EGFR-CRAF-MAPK pathway: An in vitro study

Decabromodiphenyl ether (BDE209) has been demonstrated to be associated with thyroid dysfunction and thyroid carcinoma risk as a widely used brominated flame retardants. Although dabrafenib has been confirmed to be a promising therapeutic agent for papillary thyroid carcinoma (PTC) harboring BRAFV600E mutation, the rapid acquired dabrafenib resistance has brought a great challenge to clinical improvement and the underpinning mechanisms remain poorly defined. By treating PTC-derived and normal follicular epithelial cell lines with BDE209, we assessed its impact on the MAPK pathway's activation and evaluated the resultant effects on cell viability and signaling pathways, utilizing methods such as Western blot, IF staining, and RNA-seq bioinformatic analysis. Our findings reveal that BDE209 exacerbates MAPK activation, undermining dabrafenib's inhibitory effects by triggering the EGFR pathway, thereby highlighting BDE209's potential to diminish the pharmacological efficacy of dabrafenib in treating BRAF-mutated PTC. This research underscores the importance of considering environmental factors like BDE209 exposure in the effective management of thyroid carcinoma treatment strategies.

Targeting the aryl hydrocarbon receptor with FICZ regulates IL-2 and immune infiltration to alleviate Hashimoto's thyroiditis in mice

Hashimoto's thyroiditis (HT) is the most frequent autoimmune disorder. Growing work points to the involvement of aryl hydrocarbon receptor (AhR), a ligand-dependent transcription factor, in the regulation of immune homeostasis. However, the roles of AhR and its ligands in HT remains unclear. In this study, we leveraged public human database analyses to postulate that the AhR expression was predominantly in thyroid follicular cells, correlating significantly with the thyroid infiltration levels of multiple immune cells in HT patients. Using a thyroglobulin-induced HT mouse model and in vitro thyroid follicular epithelial cell cultures, we found a significant downregulation of AhR expression in thyrocytes both in vivo and in vitro. Conversely, activating AhR by FICZ, a natural AhR ligand, mitigated inflammation and apoptosis in thyrocytes in vitro and conferred protection against HT in mice. RNA sequencing (RNA-seq) of thyroid tissues indicated that AhR activation moderated HT-associated immune or inflammatory signatures. Further, immunoinfiltration analysis indicated that AhR activation regulated immune cell infiltration in the thyroid of HT mice, such as suppressing cytotoxic CD8+ T cell infiltration and promoting anti-inflammatory M2 macrophage polarization. Concomitantly, the expression levels of interleukin-2 (IL-2), a lymphokine that downregulates immune responses, were typically decreased in HT but restored upon AhR activation. In silico validation substantiated the binding interaction between AhR and IL-2. In conclusion, targeting the AhR with FICZ regulates IL-2 and immune infiltration to alleviate experimental HT, shedding new light on the therapeutic intervention of this prevalent disease.

Inhibiting Soluble Epoxide Hydrolase Suppresses NF-κB p65 Signaling and Reduces CXCL10 Expression as a Potential Therapeutic Target in Hashimoto's Thyroiditis.

Although Hashimoto's thyroiditis (HT) is one of most common autoimmune thyroid diseases, its treatment remains focused on symptom relief. The soluble epoxide hydrolase (sEH) shows potential functions as a drug target in alleviating some autoimmune diseases; however, we seldom know its role in HT. The protein expression of sEH and related downstream molecules were evaluated by immunohistochemistry, Western blotting, ELISA, or immunofluorescence staining. RNA sequencing of tissue samples was performed to analyze differential genes and dysregulated pathways in HT and controls. The thyroid follicular epithelial cells (TFECs) and rat HT model were used to verify the biological function of sEH and the inhibition role of adamantyl-ureido-dodecanoic acid (AUDA) in HT. The sEH was significantly upregulated in HT patients compared with healthy individuals. Transcriptome sequencing showed cytokine-related pathways and chemokine expression; especially chemokine CXCL10 and its receptor CXCR3 were aberrant in HT patients. In TFECs and a rat HT model, blocking sEH by AUDA inhibitor could effectively inhibit the autoantibody, proinflammatory nuclear kappa factor B (NF-κB) signaling, chemokine CXCL10/CXCR3 expression, and type-1 helper CD4+ T cells. Our findings suggest that sEH/NF-κB p65/CXCL10-CXCR3 might be promising therapeutic targets for HT.

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.

MORPHOFUNCTIONAL CHARACTERISTICS OF THE REPRODUCTIVE SYSTEM OF COWS WITH HEMORRHAGIC ENDOMETRITIS

The article presents the results of studies of the morphofunctional characteristics of the reproductive system of cows with hemorrhagic endometritis. In the ovaries of cows, the number of primary follicles is reduced, but the number of atretic follicles is increased. The area of protoplasm and nuclei in the left ovary increases by 23.8% and 13.01% compared to the norm, in the right – by 63.4% and 41.4%, respectively. The functional activity of follicular epithelial cells in the left ovary decreases by 4.2%, in the right – by 14.6%. In case of hemorrhagic endometritis, the mass of the right ovary is 30.76% less, and the mass of the left ovary is within the normal range. The length of both oviducts is within the physiological norm. The width of the left and right oviducts is 39.93% and 13.89% less than normal. In general, the wall thickness of the left oviduct decreases by 13.3% compared to that in clinically healthy cows, while the right one, on the contrary, thickens by 33.6%. At the same time, there is a thickening of the mucous layer of the left oviduct by 37.6% compared to the norm. The submucosal and muscular layers are thinner by 43.6% and 38.4%, respectively. In the right oviduct, a thickening of the submucosal layer by 55.5% was noted, and the thickness of the muscular layer was within the normal range. The area of protoplasm and nuclei of the surface epithelium in the left oviduct decreases compared to those in clinically healthy cows by 11.7% and 10.2%, in the right – by 31.3% and 45.2%, respectively. The functional activity of cells in the left oviduct increased by 7.7%, in the right – by 35.4%.

IL-10-TG/TPO-T4 axis, the target of bis (2-ethylhexyl) tetrabromophthalate on thyroid function imbalance

Bis (2-ethylhexyl) tetrabromophthalate (TBPH) is a new type of brominated flame retardant. Some studies suggest that TBPH exposure may be associated with thyroid damage. However, there is a paucity of research on the authentic exposure-related effects and molecular mechanisms in animals or cells. In this study, we used male Sprague-Dawley (SD) rats and the Nthy ori3–1 cell line (the human thyroid follicular epithelial cell) to explore the potential effects of TBPH (5, 50, 500 mg/kg and 1, 10, 100 nM) on the thyroid. The genes and their proteins of cytokines and thyroid-specific proteins, thyroglobulin (TG), thyroid peroxidase (TPO), and sodium iodide cotransporter (NIS) were examined to investigate the possible mechanisms. At the end of the experiment, it was found that 50 and 500 mg/kg TBPH could increase the levels of total thyroxine (TT4) and free thyroxine (FT4) significantly. The messenger RNAs (mRNAs) of Tg, Tpo, Interleukin-6 (Il6), and Interleukin-10 (Il10) in the thyroid tissues from the rats treated with 500 mg/kg were enhanced clearly. Meanwhile, the mRNAs of TG, TPO, IL6, and IL10 were elevated in Nthy ori3–1 cells treated with 100 nM TBPH as well. The mRNAs of TG and TPO were elevated after the knockdown of IL6. To our surprise, after the knockdown of IL10 or the treatment of anti-IL-10-receptor (anti-IL-10-R) antibody, the mRNAs of TG and TPO were significantly reduced, and the effects of TBPH were diminished. In conclusion, our results suggested that the IL-10-IL-10R-TG/TPO-T4 axis is one important target of TBPH in the thyroid.