Papillary Thyroid Carcinoma: Current Position in Epidemiology, Genomics, and Classification

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

BACKGROUND

Papillary thyroid carcinoma (PTC) is a common endocrine malignancy. Studies have indicated that estrogen can regulate the expression of miRNAs in numerous malignancies. MiR-570-3p has been shown to have a regulatory function in various cancers. However, studies of the regulatory function of miR-570-3p and a direct link between estrogen (especially estradiol E2) and miR-570-3p in PTC have not been done.

METHODS

Expression of miR-570-3p and its downstream target DPP4 in PTC tissues and cells was predicted using bioinformatics and validated by qRT-PCR and western blot assays. We then performed a series of gain-and-loss experiments to assess the functional significance of miR-570-3p/DPP4 axis in PTC progression in vitro and in vivo. Additionally, the methylation of the miR-570-3p promoter region was examined via bioinformatics analysis and MSP. Finally, the effects of E2 on PTC progression and the correlation between DNMT1/DNMT3A and EZH2 were predicted by bioinformatic tools and proved by luciferase reporter, ChIP, and co-IP assays.

RESULTS

In PTC tumor tissues and cell lines, there was a lower expression level and a higher methylation level of miR-570-3p compared to normal tissues and cell lines. DPP4 was identified as the downstream target of miR-570-3p. Overexpression of miR-570-3p reduced the proliferative, migratory, and invasive capabilities, and promoted apoptosis, while overexpression of DPP4 reversed these effects in PTC cells. It was also discovered that DNMT1 and DNMT3A increased the CpG methylation level of the miR-570-3p promoter in an EZH2-dependent manner, which led to decreased expression of miR-570-3p. Furthermore, we observed that estrogen (E2) enhanced the methylation of miR-570-3p and suppressed its expression levels, resulting in augmented tumor growth in vivo in PTC.

CONCLUSION

Estrogen regulates the EZH2/DNMTs/miR-570-3p/DPP4 signaling pathway to promote PTC progression.

PDLIM7 Promotes Tumor Metastasis in Papillary Thyroid Carcinoma via Stabilizing Focal Adhesion Kinase Protein

Background: As an actin cytoskeleton interactor, PDZ (postsynaptic density 65-discs large-zonula occludens 1) and LIM (abnormal cell lineage 11-isket 1-mechanosensory abnormal 3) domain protein 7 (PDLIM7) was supposed to play an essential role modulating cytoskeleton. Focal adhesions (FAs), which are located at the cytomembrane terminus of actin cytoskeleton, function as a force sensor and can transform the mechanical signal to a biochemical signal. Focal adhesion kinase (FAK) localizes to and regulates signal transduction in FAs, which play an essential role in cell polarity, migration, and invasion. However, whether PDLIM7 is involved in FAs-associated signal transduction and its role in tumor invasion and metastasis remains largely unknown. Methods: A cohort of 80 patients with papillary thyroid carcinoma (PTC) at The Second Affiliated Hospital of Guilin Medical University, as well as 512 PTC samples from The Cancer Genome Atlas thyroid cancer database was utilized to analyze the expression of PDLIM7 and its association with prognosis. Survival data were assessed using Kaplan-Meier curves, whereas clinicopathological characteristics such as age, sex, tumor size, multilocality, extrathyroidal extension, lymph metastases, Hashimoto's thyroiditis, distant metastasis, and TNM stage were considered. Functional assays were performed in vitro and in a xenograft mouse model to assess the role of PDLIM7 in PTC cell lines. The colocalization of PDLIM7 with FAK and integrin alpha V (ITGAV) was determined using immunofluorescence assay and immunoprecipitation assay. Protein expression levels in cell and tissue biopsies were measured through Western blotting and immunohistochemistry. Results: (1) The PDLIM7 protein frequently upregulated in both PTC tissues and cells, and overexpression of PDLIM7 is associated with advanced clinicopathological characteristics. (2) Knockdown of PDLIM7 effectively inhibits cell proliferation, migration, and invasion in PTC cell lines in vitro. (3) Knockdown of PDLIM7 hinders the growth and metastasis of TPC-1 xenografts in vivo. (4) PDLIM7 demonstrates colocalization with both FAK and the FA molecule ITGAV and the knockdown of PDLIM7 resulted in disassembly of FAs and proteosome-dependent degradation of FAK in PTC cell lines. Conclusions: PDLIM7 function as an oncoprotein in PTC to promote metastasis, and a novel underlying mechanism is proposed that PDLIM7 keeps FAK protein from proteosome-dependent degradation.

SYVN1 modulates papillary thyroid carcinoma progression by destabilizing HMGB1

E3 ubiquitin ligase synoviolin (SYVN1) has been reported to participate in many human cancers. This study aimed to investigate SYVN1's roles and molecular pathways in papillary thyroid cancer (PTC). The functions of SYVN1 in PTC were further analyzed using gain- and loss-of-function methods and numerous investigations in cellular function and molecular biology. The findings demonstrated that the overexpression of SYVN1 markedly suppressed the proliferation, migration, and invasion of PTC cell lines (NPA87 and TPC-1). We found that SYVN1 interacted with HMGB1 and promoted its ubiquitination and degradation. In addition, SYVN1 effectively impairs cell proliferation, migration, invasion, and the formation of tumor xenografts in mice models. However, this effect may be partly reversed by overexpressing HMGB1. Thus, SYVN1 may inhibit the proliferation, migration, and invasion of PTC cells by disrupting HMGB1. Consequently, SYVN1 might be considered a promising therapeutic target for PTC.

TIROSEC: Molecular, Clinical and Histopathological Profile of Papillary Thyroid Carcinoma in a Colombian Cohort

INTRODUCTION

In Colombia, thyroid cancer ranks among the highest incidences, yet our population lacks studies on its molecular profile. This study aims to characterize clinical, histopathologic and molecular data in a Colombian cohort with papillary thyroid carcinoma (PTC).

METHODS

A retrospective review of clinical history, clinicopathologic characteristics, treatment and 5-10-year follow-up for all patients was done. DNA and RNA were extracted from formalin-fixed paraffin-embedded (FFPE) tissue using the Quick-DNA & RNA FFPE Min iPrep kit (Zymo Research). Next-generation sequencing (NGS) analysis was performed with SOPHiA Solid Tumor Solutions kit (SOPHiA GENETICS). Tumor mutation genomic analysis used SOPHiA DDM™ platform, with descriptive analysis reporting frequencies, means and associations via chi-square analysis.

RESULTS

Among 231 sequenced patients, mean age at diagnosis was 46 (± 12.35) years, with higher frequency in women (81.82%). Two cases were reclassified as non-invasive follicular thyroid neoplasm (NIFT-P); an NRAS mutation was found in one of them. Predominant histologic subtype was classic PTC (57.64%) followed by tall cell (28.82%). Of the 229 sequenced carcinomas, mutations were identified in 186 cases, including BRAF, IDH1, RAS and PIK3CA. Notable copy number variations (CNVs) were PDGFRA, CDK4 and KIT, with RET being the most frequent gene fusion, including CCDC6-RET in two classic subtype cases.

CONCLUSION

This is the first study in Colombia (TIROSEC) to our knowledge that integrates molecular and histopathologic profiles enriching our local comprehension and knowledge of PTC. The identification of target mutations such as BRAF, RET and NTRK fusions holds the potential to guide targeted therapies for tumor recurrence and predict aggressive behavior.

Sentinel lymph node mapping: current applications and future perspectives in thyroid carcinoma

Sentinel lymph node (SLN) mapping is a standard, minimally-invasive diagnostic method in the surgical treatment of many solid tumors, as for example melanoma and breast cancer, for detecting the presence of regional nodal metastases. A negative SLN accurately indicates the absence of metastases in the other regional lymph nodes (LN), thus avoiding unnecessary lymph nodal dissection. Papillary thyroid carcinoma (PTC) is the most common type of thyroid carcinoma (TC) with cervical LN metastases at diagnosis in 20-90%, and nodal involvement correlates with local persistence/recurrence. The SLN in PTC is an intraoperative method for staging preoperative N0 patients and for detecting metastatic LNs "in and outside" the cervical LN central compartment; it represents an alternative method to prophylactic central neck node dissection. In this review we summarize different methods and results of the use of SLN in TC. The SLN identification techniques currently used include the selective vital-dye (VD) method, 99mTc-nanocolloid planar lymphoscintigraphy with intraoperative use of a hand-held gamma probe (LS), the combination LS + VD, and the combination LS and preoperative SPECT-CT (LS + SPECT/CT). The application of the SLN procedure in TC has been described in many studies, however, the techniques are heterogeneous, and the role of SLN in TC, with indications, results, advantages and limits, is still debated.

The usefulness and utilization of Gold-finger retractor for endoscopic thyroid surgery

Aims

In endoscopic surgery, the visual field is frequently obstructed by muscles, blood, and even smoke. To overcome this problem, we have developed a new detachable Gold-finger retractor for narrow-space surgery.

Methods

Gold-finger retractor was used in 30 patients to facilitate surgical field exposure and smoke discharge, while in 27 patients, percutaneous silk thread suspension was employed for the same purpose. Both groups underwent endoscopic unilateral thyroidectomy and unilateral central lymph node dissection via oral vestibular microincision combined with the axillary-assisted approach. A comparative analysis was conducted to evaluate the efficacy of the Gold-finger retractor and silk thread suspension in relation to intraoperative exposure effect, surgical fluency, surgeon's comfort, operation time, postoperative complications, and length of hospital stay. This analysis was based on surgical video recordings and postoperative indicators.

Results

With Gold-finger retractor support, surgeons were able to perform meticulous operations. Complication rates were similar between the two groups, and no serious complications occurred. The number of lymph nodes dissected in the Gold-finger group was significantly greater than that in the routine group (12.43 ± 6.18 and 5.7 ± 2.95, respectively). Further analysis of surgeons' comfort (visibility and convenience in peeling) revealed that the Gold-finger group was significantly better. Electrosurgery smoke was removed effectively with Gold-finger, and the operation time was significantly reduced.

Conclusion

In thyroid surgery, Gold-fingers enhance visual field resolution, avoid muscle cutting, save time, and improve the surgical experience.

Papillary thyroid carcinoma with nodular fasciitis-like stroma - an unusual variant with distinctive histopathology: A case report

BACKGROUND

Papillary thyroid carcinoma (PTC) is regarded as a fairly common endocrine malignancy, which can be divided into different multiple variants due to wide morphologic differences. The majority of PTC variants have been reported, but PTC with nodular fasciitis-like stroma (NFS) is a rare pathological variant and has been infrequently reported in the relevant literature. This condition involves abundant reactive stromal components rich in spindle cells, which may account for 60%-80% of the tumor along with a typical papillary carcinoma.

CASE SUMMARY

A 44-year-old man presented with a 4-mo history of a palpable mass over the anterior aspect of the left neck, the tumor demonstrated gradual enlargement but was painless during the 4 mo prior to discovery. Thyroid function test results were normal. Physical examination showed an enormous and firm nodular mass in the left lobe of the thyroid gland extending to the level of the hyoid bone. Ultrasonography of the neck revealed a well-defined heterogeneous lesion measuring around 5.0 cm × 4.0 cm with a hypoechoic complex nodule, decreased vascularity and speckles of microcalcification. The patient underwent left thyroidectomy with central compartment lymph node dissection. Final histopathological examination confirmed the diagnosis of PTC with extensive fibromatosis-like stroma combined with typical PTC. The patient was asymptomatic at the 3-mo follow-up.

CONCLUSION

PTC-NFS is a rare pathological variant and its diagnosis and prognosis may be similar to typical papillary carcinoma.

Reveal the potential molecular mechanism of circRNA regulating immune-related mRNA through sponge miRNA in the occurrence and immune regulation of papillary thyroid cancer

BACKGROUND

Papillary thyroid cancer (PTC) is the most common endocrine malignant tumour. The purpose of this study was to explore the potential molecular mechanism of circRNA regulating immune-related mRNA through sponge miRNA in the occurrence and immune regulation of PTC.

METHODS

All data were downloaded from public databases, such as GEO, Immport and TCGA. Differentially expressed (DE) mRNAs (DEmRNAs), DEmiRNAs and DEcircRNAs were identified using metaMA and limma packages. Subsequently, immune-related DEmRNAs were screened, and circRNA-miRNA-mRNA (ceRNA) regulatory network was constructed. In addition, functional annotation, protein-protein interaction (PPI) network construction, immune cell infiltration analysis and Pearson correlation analysis were performed. Finally, qRT-PCR validation and cell experiments were also performed.

RESULTS

In total, 2962 DEmRNAs, 78 DEmiRNAs and 51 DEcircRNAs were obtained. Subsequently, 195 immune-related DEmRNAs were obtained based on Immport database. Cytokine-cytokine receptor interaction was the only signalling pathway obtained in KEGG analysis. Then, 8 hub immune-related DEmRNAs were identified based on PPI network and CytoHubba plug-in. Subsequently, ceRNA sub-network containing hub immune-related DEmRNAs was extracted from ceRNA regulatory network. In ceRNA sub-network, hsa_circ_0082182-hsa-miR-18b-5p-FGF1/PDGFC, hsa_circ_0016404-hsa-miR-1275-FGF1/CTSB/IL13RA1, hsa_circ_0070100-hsa-miR-27a-3p/hsa-miR-27b-3p-TGFBR3, hsa_circ_0060055/hsa_circ_0038718-hsa-miR-150-3p-CXCL14, hsa_circ_0030427/hsa_circ_0002917-hsa-miR-22-3p-BMP7 and hsa_circ_0030427/hsa_circ_0002917-hsa-miR-125a-5p-LIFR axes were identified. Moreover, FGF1, PDGFC, CTSB, IL13RA1, TGFBR3, CXCL14, BMP7, LIFR, hsa-miR-125a-5p, hsa-miR-1275, hsa-miR-150-3p, hsa-miR-18b-5p and hsa-miR-27b-3p were also found to have good diagnostic accuracy and may be potential novel diagnostic markers for PTC. XCell analysis showed that the levels of immune cell infiltration (including Tregs, HSC, DC and Monocytes) were significantly different between the PTC and the control groups. Knockdown of the expression of hsa_circ_0082182 significantly inhibits the activity, proliferation, migration and invasion of TPC-1 cells.

CONCLUSION

Several circRNA-miRNA-mRNA axes identified in this study may be related to the occurrence, progression and survival of PTC. This lays a theoretical foundation for further understanding the molecular mechanism of PTC, and also contributes to clinical management and research.

SRPX2 Promotes Tumor Proliferation and Migration via the FAK Pathway in Papillary Thyroid Carcinoma

Thyroid cancer is the most common form of endocrine cancer around the world, and among which papillary thyroid carcinoma (PTC) is the most ubiquitous pathological sub-kind. Sushi repeat-containing protein X-linked 2 (SRPX2) was reported to be an independent prognostic factor and significantly overexpressed in advanced PTC patients. However, the biological functions of SRPX2 remain ambiguous in PTC. Here, we explored SRPX2 expression profiles and functions in PTC, finding that SRPX2 expression was remarkably upregulated in PTC tissues and cell lines. Further colony formation, CCK-8, as well as transwell assay, suggested that SRPX2 silencing remarkably dampened PTC growth and migration. Mouse xenograft models were established to find that SRPX2 silence remarkably suppressed PTC proliferation and migration in vivo. Following mechanism studies revealed that SRPX2 realized its functions in the PTC process partially through activating the Focal adhesion kinase (FAK) phosphorylation. In conclusion, this study investigated the functions and mechanisms of the SRPX2/FAK pathway in PTC progression. SRPX2 could act as a prospective biologic signature and therapeutic target molecule for PTC.

Analysis of the Mechanism of Maslinic Acid on Papillary Thyroid Carcinoma Based on RNA-Seq Technology

Objective

This study analyzed gene sequence changes in the thyroid papillary carcinoma (PTC) cell line TPC-1 treated with the natural compound maslinic acid (MA) through RNA-sequencing (RNA-seq) and identified the necessary genes to provide a basis for the study of the molecular mechanism of action of MA in PTC treatment.

Methods

RNA-seq technology was used to detect genetic differences between the normal cell group (Nthy-ori 3-1) and the TPC-1 cell group (N vs T). Then, gene ontology (GO) analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, Venn diagram analysis of shared genes, and protein–protein interaction (PPI) network analysis were used to analyze the therapeutic effect of the MA on TPC-1 cells. Real-time quantitative PCR (qRT-PCR) was used to verify six key genes.

Results

GO and KEGG analyses showed that four crucial signaling pathways are related to TPC development: cytoplasmic molecule (cell adhesion molecules), neuroactive ligand–receptor interaction, tumor transcriptional disorder, and cytokine–cytokine interaction. The Venn diagram revealed 434 genes were shared between the MA vs T-group and 387 genes were shared between the MATH vs T and N vs T groups. PPI and ClueGO showed that NLRP3, SERPINE1, CD74, EDN1, HMOX1, and CXCL1 genes were significantly associated with PTC, while CXCL1, HMOX1, and other factors were mainly involved in the cytokine–cytokine interaction. The qRT-PCR results showed that the expression of NLRP3, EDN1, HMOX1, and CXCL1 genes was significantly upregulated in the TPC-1 group but significantly downregulated after MA treatment (p < 0.01). SERPINE1 and CD74 genes were not expressed in TPC-1 cells, whereas they were significantly upregulated after MA treatment (p < 0.01).

Conclusions

This present study proves for the first time that MA can treat PTC, and the preliminary identification of key genes and rich signal transduction pathways provides potential biomarkers. It also provides potential biomarkers for the treatment of PTC with the natural compound MA and preliminarily discusses the therapeutic mechanism of action of MA against PTC, which is helpful for the further diagnosis and treatment of PTC patients.

Thyroid Diseases and Thyroid Asymptomatic Dysfunction in People Living With HIV

Thyroid diseases (TDs) and thyroid asymptomatic dysfunctions (TADs) are correlated with Human Immunodeficiency virus (HIV) infection and Acquired ImmunoDeficiency Syndrome (AIDS) as well as many endocrine dysfunctions and dysregulation of hormonal axes. To date, available studies on People Living With HIV (PLWH) affected by thyroid diseases and asymptomatic dysfunctions are few and rather controversial. The purpose of the present non-systematic literature review is to recap the current knowledge on the main features of thyroid dysfunctions and disorders in PLWH. Large cohort studies are needed for a better comprehension of the impact, evolution and treatment of thyroid pathologies in the HIV-infected population.