Gene expression profile in functioning and non-functioning nodules of autonomous multinodular goiter from an area of iodine deficiency: unexpected common characteristics between the two entities

Expression and Function of Long Non-coding RNA in Endemic Cretinism

Endemic cretinism (EC) is one of the most severe iodine deficiency disorders, leading to typical symptoms such as neurodevelopmental impairments or mental deficits. In addition to environmental factors, the pathogenesis of its genetic contribution remains unclear. The study revealed the differential expression profiles of long non-coding RNA(lncRNA) and messenger RNA(mRNA) based on high-throughput RNA-seq. GO and KEGG analyses were used to annotate the function and pathway of differentially expressed (DE) mRNA and co-expressed mRNA. The protein-protein interaction(PPI) network was established. The expression levels of three lncRNAs and six mRNAs were validated by quantitative real-time PCR analysis (qRT-PCR) and subjected to correlation analysis. Compared to controls, a total of 864 lncRNAs and 393 mRNAs were differentially expressed. The PPI network had 149 nodes and 238 edges, and three key protein-coding genes were observed. Levels of LINC01220 and target mRNA IDO1 were statistically elevated in EC patients. Differentially expressed lncRNA may be a new potential player in EC. LINC01220 and IDO1 might interact with each other to participate in EC. The biological process of regulation of postsynaptic membrane potential and the Rap1 signaling pathway might exert a regulating role in the pathophysiological process of EC. Our findings could provide more theoretical and experimental evidence for investigating the pathophysiological mechanisms of EC.

The common pathogenesis of nodular goiter in both sexes: An exploration into gene expression and signaling pathways

The past few years have witnessed an increasing incidence of nodular goiter (NG), with a well-documented higher prevalence in females than males. This gender disparity has led research to focus primarily on female subjects, potentially overlooking common pathogenic mechanisms in both sexes. In this study, we investigated the shared pathogenesis of NG in males and females. Utilizing a rat model and RNA sequencing, we identified differentially expressed genes associated with the disease. We further validated these findings in normal human thyroid cells and human papillary thyroid cancer cells. A randomized experiment was conducted with equal numbers of male and female rats divided into control and NG model groups. The NG model was established using propylthiouracil and various assessments such as thyroid ultrasonography, thyroid index, thyroid function, and thyroid histology were performed. Transcriptome analysis revealed numerous upregulated and downregulated genes in both male and female model groups. Key genes like KDR, FLT1, PDGFB, and CAV1, and pathways including PI3K-Akt, MAPK, Ras, fluid shear stress and atherosclerosis, calcium signaling, and Rap1 signaling pathways were linked with the disease. Western blot and immunofluorescence analysis confirmed these findings, which were further supported by cell-based experiments. In conclusion, our findings suggest that abnormal expression of specific genes and pathways leading to irregular cell growth, blood vessel formation, and inflammation may be common factors in the pathogenesis of NG in both males and females.

Prevalence of DICER1 variants in large multinodular goiter: thyroid function, clinical and imaging characteristics

Objective

Mutations in DICER1 are found in differentiated thyroid carcinoma (DTC) and in multinodular goiter (MNG) at a younger age with other tumors, which characterizes DICER1 syndrome. DICER1 is one driver to DTC; however, it is also found in benign nodules. We speculated that patients with mutations in DICER1 may present long-lasting MNG. Our aim was to investigate the frequency of DICER1 variants in patients with MNG.

Subjects and methods

Patients who submitted to total thyroidectomy due to large MNG with symptoms were evaluated. DICER1 hotspots were sequenced from thyroid nodule samples. To confirm somatic mutation, DNA from peripheral blood was also analyzed.

Results

Among 715 patients, 154 were evaluated with 56.2 ± 12.3 years old (28-79) and the thyroid volume was 115.7 ± 108 mL (16.2-730). We found 11% with six DICER1 variations in a homo or heterozygous state. Only rs12018992 was a somatic DICER1 variant. All remaining variants were synonymous and likely benign, according to the ClinVar database. The rs12018992 was previously described in an adolescent with DTC, measuring 13 mm. There were no significant differences according to gender, familial history of goiter, age, thyroid volume, TSH and TI-RADS classification between DICER1 carriers. Free T4 were lower in patients with DICER1 polymorphisms (13.77 ± 1.8 vs. 15.44 ± 2.4 pmol/L, p = 0.008), regardless of TSH levels.

Conclusion

We conclude that germline DICER1 variants can be found in 11% of large goiters but no second-hit somatic mutation was found. DICER1 is one driver to thyroid lesion and a second-hit event seems unnecessary in the MNG development.

Exploring the effect and mechanism of Haizao Yuhu decoction containing three variants of glycyrrhiza on goiter using an integrated strategy of network pharmacology and RNA sequencing

ETHNOPHARMACOLOGICAL RELEVANCE

Haizao Yuhu decoction (HYD) is a classic Chinese herbal formula described in the surgical monographs of the Ming Dynasty "Waikezhengzong." It has been widely used to treat goiter for approximately 500 years and found to be particularly effective. HYD contains glycyrrhiza and sargassum. This pair of herbs belongs to "18 incompatible medicaments" of traditional Chinese medicine theory. Although these two herbs are opposite, our preliminary study proved that they have superior effect when added into HYD at 2 times the dose of Chinese Pharmacopoeia. However, the species of glycyrrhiza in HYD that are the most effective have not been recorded in ancient Chinese medical texts. According to the Chinese Pharmacopoeia, glycyrrhiza is divided into the following three species: Glycyrrhiza uralensis Fish., G. glabra L., and G. inflata Bat. The effect of HYD containing different species of glycyrrhiza and their mechanisms remain to be further explored.

AIM OF THE STUDY

To investigate the effect of HYD containing three species of glycyrrhiza on goiter, and to elucidate the molecular mechanism using network pharmacology combined with RNA sequencing (RNA-seq).

MATERIALS AND METHODS

A rat model of goiter was established by 14 days of intragastric gavage of propylthiouracil (PTU), and the rats were treated for 4 weeks with HYD containing three different species of glycyrrhiza. The body weight and rectal temperature of rats were tested weekly. At the end of the experiment, the serum and thyroid tissues of rats were collected. The effect of the three HYDs was assessed based on general observations (including body weight, rectal temperature, and living status of rats), absolute/relative thyroid weight, thyroid function (including triiodothyronine, thyroxine, free triiodothyronine, free thyroxine, and thyroid-stimulating hormone levels), and thyroid tissue pathology. Next, we explored their pharmacological mechanisms using network pharmacology combined with RNA-seq and validated key targets using real-time quantitative reverse-transcription polymerase chain reaction (RT-qPCR), western blotting (WB), and immunofluorescence (IF) assays.

RESULTS

The three HYDs reduced the absolute/relative weights of thyroid tissues and improved the pathological structure, thyroid function, and general findings of rats with goiter. Overall, the effect of HYD-G. uralensis Fish. (HYD-U) was better. Results from network pharmacology and RNA-seq jointly suggested that both the pathogenesis of goiter and the mechanism of action of HYD for goiter were related to the phosphatidylinositol 3-kinase-protein kinase B (PI3K-Akt) pathway. We validated the key targets in the pathway, namely, vascular endothelial growth factor (VEGF) A, VEGF receptor 2, phosphoinositide-3-kinase regulatory subunit 1 (PIK3R1) and its encoded protein PI3K (p85), AKT serine/threonine kinase 1 (AKT1), phospho-AKT and cyclin D1 using RT-qPCR, WB, and IF assays. The PI3K-Akt pathway was hyperactivated in rats with PTU-induced goiter, whereas the three HYDs could inhibit the pathway.

CONCLUSION

This study confirmed the definite effect of the three HYDs in the treatment of goiter, and HYD-U was found to be more effective. The three HYDs inhibited angiogenesis and cell proliferation in goiter tissue by inhibiting the PI3K-Akt signaling pathway.

Diagnostic Effectiveness of Dual Source Dual Energy Computed Tomography for Benign and Malignant Thyroid Nodules

Objective

To evaluate the diagnostic effectiveness of dual source dual energy computed tomography (DS-DECT) for benign and malignant thyroid nodules.

Methods

Between January 2019 and December 2021, 60 patients with surgically and pathologically verified thyroid nodules treated at our institution were recruited. DS-DECT was administered to all patients. The iodine content of lesioned and normal tissues, the normalized iodine concentration (NIC) and standardized CT values of benign and malignant nodules, the consistency of examination results and pathological findings, and diagnostic effectiveness were all investigated.

Results

The diagnosis accuracy was the same as that of surgical pathology, producing a 100% accuracy for the 60 patients with thyroid nodules (42 were benign and 18 were malignant). The iodine content of lesioned solid tissue differed significantly from that of normal tissue, as did the iodine content of malignant and benign nodules (P < 0.05). In the arterial phase, no significant difference was found in NIC and standardized CT values between benign and malignant nodules (P > 0.05). The optimal critical NIC for differentiating benign and malignant nodules in the venous phase was 0.74 and the standardized CT value was 0.79 HU according to the receiver operating characteristics (ROC) curve. Malignant nodules were diagnosed when the NIC was <0.74 and the standardized CT value was <0.79 HU, with AUC values of 0.89 and 0.93, respectively, where the sensitivity and specificity of the differential diagnosis of NIC were 90.48% (38/42) and 88.89% (16/18), respectively, and those of the differential diagnosis of standardized CT value were 92.86% (39/ 42) and 94.44% (17/18), respectively. The diagnosis accuracy of DS-DECT was 100%, and the diagnostic results of morphological characteristics and pathological testing were consistent. The sensitivity and specificity of the NIC values and standardized CT values in the venous phase differential diagnosis of benign and malignant nodules were compatible with the morphological differential diagnosis.

Conclusion

DS-DECT is highly accurate in determining the benignity and malignancy of thyroid nodules and has a strong potential for clinical promotion to allow for prompt treatment.