Papillary Thyroid Carcinoma Cell Research Articles

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.

Circ-METTL15 stimulates the aggressive behaviors of papillary thyroid cancer cells by coordinating the miR-200c-3p/XIAP axis.

Papillary thyroid carcinoma (PTC) is the most common form of thyroid cancer. The critical importance of circular RNA (circRNA) in a range of cancer types has been lately recognized. However, research on the functions of circRNAs in PTC has been limited thus far. Therefore, this research aimed at exploring the function and mechanism of circ-methyltransferase-like 15 (METTL15) in PTC cells. Quantitative measurements of circ-METTL15, miR-200c-3p, and X-linked inhibitor of apoptosis protein (XIAP) in PTC cells were conducted using reverse transcription-quantitative polymerase chain reaction or Western blot analysis. To investigate cell growth, cell counting kit-8 and colony formation tests were employed, apoptosis was analyzed using flow cytometry, and migration and invasion were studied through Transwell assays. The targeted binding sites between miR-200c-3p and circ-METTL15 or XIAP were predicted by starBase and then verified by dual luciferase reporter assay. circ-METTL15 and XIAP were upregulated in the PTC cells, while miR-200c-3p was downregulated. Downregulating circ-METTL15 or upregulating miR-200c-3p resulted in inhibited proliferation, migration, and invasion of PTC cells, while promoting apoptosis. miR-200c-3p was the downstream molecule of circ-METTL15, and XIAP was the direct target of miR-200c-3p. Forcing XIAP expression obstructed circ-METTL15 silencing to inhibit PTC cell activity. By coopting miR-200c-3p/XIAP, Circ-METTL15 stimulates aggressive behavior in PTC cells.

Extra-nuclear TERT counteracts oxidative stress and promotes progression in papillary thyroid carcinoma

The reactivation of TERT is associated with poor outcome in papillary thyroid cancer (PTC). Extra-telomeric functions of TERT were reported, with a protective role against oxidative stress (OS). The aim of the present study was to explore the extra-nuclear TERT localization in PTC and its role in cancer progression.TERT nuclear export under OS were analyzed in K1 PTC cell line. We investigated the role of different TERT localizations using specific TERT constructs that limit its localization to the nucleus or to the mitochondria. The effect of SRC kinase inhibitor PP2, which reduces TERT nuclear export, was investigated as well. Moreover, TERT localization was analyzed in 39 PTC tissues and correlated with the genetic profile and the level of OS, DNA damage and apoptosis in the tumors and with the clinical characteristics of the patients.We demonstrated that TERT is exported from the nucleus in response to OS induced either from H2O2 or the BRAF inhibitor PLX4720. We proved that extra-nuclear TERT reduces mitochondrial OS and induces mitochondrial fragmentation. Moreover, limiting mitochondrial TERT localization reduced proliferation, migration, AKT phosphorylation and glycolysis and increased DNA damage and p21 expression. Finally, in PTC tissues the fraction of mitochondrial/nuclear TERT resulted inversely correlated with OS and p21 expression and associated with tumor persistence.In conclusion, our data indicate that extra-nuclear TERT is involved in reducing the effect of excessive OS, thus promoting cancer cell survival. Extra-nuclear TERT may thus represent a marker of cancer progression and a possible therapeutic target in PTC.

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

BackgroundAlthough 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.MethodsIn 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.ResultsThe 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.ConclusionTaken together, our research found that circPHGDH downregulation reduced PTC progression via miR-122-5p/PKM2 axis regulation mediated by aerobic glycolysis.

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

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. 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. 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). 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.

Mcl-1 mediates intrinsic resistance to RAF inhibitors in mutant BRAF papillary thyroid carcinoma

Papillary thyroid carcinoma (PTC) is the most frequent form of thyroid cancer. PTC commonly presents with mutations of the serine/threonine kinase BRAF (BRAFV600E), which drive ERK1/2 pathway activation to support growth and suppress apoptosis. PTC patients often undergo surgical resection; however, since the average age of PTC patients is under 50, adverse effects associated with prolonged maintenance therapy following total thyroidectomy are a concern. The development of mutant-selective BRAF inhibitors (BRAFi), like vemurafenib, has been efficacious in patients with metastatic melanoma, but the response rate is low for mutant BRAF PTC patients. Here, we assay the therapeutic response of BRAFi in a panel of human PTC cell lines and freshly biopsied patient samples. We observed heterogeneous responses to BRAFi, and multi-omic comparisons between susceptible and resistant mutant BRAF PTC revealed overrepresented stress response pathways and the absence of compensatory RTK activation – features that may underpin innate resistance. Importantly, resistant cell lines and patient samples had increased hallmarks of failed apoptosis; a cellular state defined by sublethal caspase activation and DNA damage. Further analysis suggests that the failed apoptotic phenotypes may have features of “minority mitochondrial outer membrane permeabilization (MOMP)” – a stress-related response characterized by fragmented and porous mitochondria known to contribute to cancer aggressiveness. We found that cells presenting with minority MOMP-like phenotypes are dependent on the apoptotic regulator, Mcl-1, as treatment with the Mcl-1 inhibitor, AZD5991, potently induced cell death in resistant cells. Furthermore, PI3K/AKT inhibitors sensitized resistant cells to BRAFi; an effect that was at least in part associated with reduced Mcl-1 levels. Together, these data implicate minority MOMP as a mechanism associated with intrinsic drug resistance and underscore the benefits of targeting Mcl-1 in mutant BRAF PTC.

FLNA overexpression promotes papillary thyroid cancer aggression via the FAK/AKT signaling pathway.

Filamin A (FLNA) is a member of the filamin family and has been found to be critical for the progression of several cancers. However, its biological function in papillary thyroid cancer (PTC) remains largely unexplored. Data from The Cancer Genome Atlas (TCGA) databases were utilized to analyze the FLNA expression level and its influence on the clinical implications of patients with PTC. Gene Expression Omnibus (GEO) and qRT-PCR was used to verify the expression levels of FLNA in PTC. Kaplan-Meier survival analysis was conducted to evaluate the prognostic value of FLNA in PTC. Transwell assays and wound healing were performed to examine the biological function of FLNA knockdown in PTC cells. Gene set enrichment analysis (GSEA) and Western blotting were conducted to investigate the potential mechanisms underlying the role of FLNA in PTC progression. In addition, the relationship between FLNA expression and the tumor immune microenvironment (TME) in PTC was explored. FLNA was significantly upregulated in PTC tissues. High expression levels of FLNA was correlated with advanced TNM stage, T stage, and N stage, as well as poor disease-free interval (DFI) and progression-free interval (PFI) time in PTC patients. Moreover, we found that FLNA knockdown inhibited the migration and invasion of PTC cells. Mechanistically, FLNA knockdown inhibited epithelial-mesenchymal transition (EMT) in PTC and affected the activation of the FAK/AKT signaling pathway. In addition, FLNA expression was associated with TME in PTC. FLNA may be regarded as a new therapeutic target for PTC patients.

Tumor‑suppressive effects of Smad‑ubiquitination regulator 2 in papillary thyroid carcinoma.

Smad-ubiquitination regulator 2 (SMURF2) functions as a homolog of E6AP carboxyl terminus-type E3 ubiquitin ligase to regulate cell cycle progression and tumor growth factor expression. SMURF2 has been revealed to function as a tumor suppressor in a number of cancers; however, its function in papillary thyroid carcinoma (PTC) remains largely unknown. Therefore, the aim of the present study was to investigate the function of SMURF2 in PTC. Reverse transcription-quantitative PCR and western blotting were used to detect cellular expression of SMURF2 in vitro. After increasing or inhibiting the expression of SMURF2, MTT was used to detect the effect on tumor cell proliferation and Transwell assays were used to detect the effect on tumor cell migration and invasion. Finally, ELISA was used to detect the effects on glucose and glutamine metabolism in tumor cells and the findings revealed that SMURF2 was downregulated in PTC tissues. Moreover, SMURF2 inhibited the proliferation, invasion and migration of PTC cells, and promoted their apoptosis. Finally, SMURF2 inhibited cell glycolysis and glutaminolysis and affected metabolism in the PTC cell line, TPC-1. Thus, the findings of the present study suggest that SMURF2 may be a potential target in the treatment of PTC.

Bergapten attenuates human papillary thyroid cancer cell proliferation by triggering apoptosis and the GSK-3β, P13K and AKT pathways.

Over the past few decades, thyroid cancer (TC) incidence has steadily increased globally. The most common TC is human papillary thyroid carcinoma (PTC), which is poorly responsive to the current treatments. Hence, finding a successful therapeutic is urgently required. Bergapten (BG) is a furanocoumarin, a natural psoralen derivative isolated from numerous species of citrus and bergamot oil that has demonstrated anti-tumor activity. However, there are no reports available on the efficacy of BG on PTC cells. The current research investigated the anti-cancer activity of BG on human BCPAP cells, with cytotoxicity and apoptosis evaluated using MTT assay, AO/EB, DAPI, PI, ELISA, mRNA, and western blot. Bergapten (control group, 10 μM/mL and 15 μM/mL) inhibited PTC cell proliferation and stimulated apoptosis by enhancing Bax and caspase and reducing Bcl-2, cyclin-D1, c-myc, and survivin in a dose-dependent manner. Furthermore, BG expressively attenuated PI3K/AKT/GSK-3β signaling, creating an uneven Bax/Bcl-2 ratio that triggered Cyt-c, caspase cascade and apoptosis in human PTC cells. Our findings emphasize that BG has the potential to be used as a protective natural remedy for human PTC cells.

Dihydrotanshinone I exhibits antitumor effects via β-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 β-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.

BCL9 is a Risk Factor of Neck Lymph Nodes Metastasis and Correlated with Immune Cell Infiltration in Papillary Thyroid Carcinoma.

B-cell lymphoma 9 (BCL9), a key transcription co-activator of the Wnt pathway, contributed to tumor progression and metastasis in various tumors, whereas, the role of BCL9 in papillary thyroid cancer (PTC) has not been investigated. We acquired PTC gene expression data from The Cancer Genome Atlas (TCGA) database. Fifty-nine PTC tissues were applied to validate the clinical significance of BCL9. Cell experiments were applied to investigate the role of BCL9. Bioinformatics analysis was employed to investigate the biological functions of BCL9. We found that BCL9 was higher expressed (P < 0.05) and an independent risk factor for lymph node metastasis (OR = 3.770, P = 0.025), as well as associated with poorer progression-free survival (PFS) (P = 0.049) in PTC. BCL9 knockdown inhibited proliferation and invasion of PTC cells. BCL9 was positively associated with the key genes of Wnt/β-catenin and MAPK pathway by co-expression analysis. GO, KEGG and GSEA analysis showed BCL9 might participated in PPAR, cAMP, and focal adhesion pathway. CIBERSORT analysis found BCL9 was negatively associated with CD8+ T cells and NK cell infiltration and positively with PD-L1 expression. Therefore, BCL9 was associated with lymph node metastasis and shorter PFS of PTC, due to promotion of PTC cell proliferation and invasion, activation of Wnt/β-catenin and MAPK pathway, inhibition of CD8+ T and NK cell infiltration, and promotion of PD-L1 expression.

MiR-374a/b-5p Suppresses Cell Growth in Papillary Thyroid Carcinoma Through Blocking Exosomal ANXA1-Induced Macrophage M2 Polarization.

Papillary thyroid carcinoma (PTC), comprising 85% of all thyroid cancers, is an epithelial malignancy. The potential for malignant transformation in normal cells by thyroid cancer cells via exosomal Annexin A1 (ANXA1) delivery is investigated in this study. Our aim is to determine the impact of PTC cells on macrophage polarization through exosomal ANXA1 secretion and its implications for tumor progression.Exosomes in PTC cells were examined using transmission electron microscopy, exosome labeling, and nanoparticle tracking analysis. Real-time quantitative polymerase chain reaction was employed to quantify gene expression levels. Protein levels were determined through Western blot analysis. The interplay between genes was assessed using luciferase reporter and RNA pull-down assays. Functional experiments were conducted to investigate PTC cell proliferation and apoptosis.Our findings reveal that ANXA1 promotes PTC cell proliferation and inhibits apoptosis. Exosomes derived from PTC cells were found to promote macrophage M2 polarization. ANXA1 stimulates M2 polarization through the activation of the PI3K/AKT pathway. MicroRNA-374a-5p (miR-374a-5p) and microRNA-374b-5p (miR-374b-5p) were identified as inhibitors of ANXA1 expression and PI3K/AKT pathway activity, thereby inhibiting macrophage M2 polarization. Furthermore, miR-374a-5p and miR-374b-5p were observed to suppress PTC cell proliferation through their regulatory action on ANXA1.Our study suggests that miR-374a/b-5p inhibits PTC cell growth by blocking the macrophage M2 polarization induced by exosomal ANXA1.

BUB1/KIF14 complex promotes anaplastic thyroid carcinoma progression by inducing chromosome instability.

Chromosome instability (CIN) is a common contributor driving the formation and progression of anaplastic thyroid cancer (ATC), but its mechanism remains unclear. The BUB1 mitotic checkpoint serine/threonine kinase (BUB1) is responsible for the alignment of mitotic chromosomes, which has not been thoroughly studied in ATC. Our research demonstrated that BUB1 was remarkably upregulated and closely related to worse progression-free survival. Knockdown of BUB1 attenuated cell viability, invasion, migration and induced cell cycle arrests, whereas overexpression of BUB1 promoted the cell cycle progression of papillary thyroid cancer cells. BUB1 knockdown remarkably repressed tumour growth and tumour formation of nude mice with ATC xenografts and suppressed tumour metastasis in a zebrafish xenograft model. Inhibition of BUB1 by its inhibitor BAY-1816032 also exhibited considerable anti-tumour activity. Further studies showed that enforced expression of BUB1 evoked CIN in ATC cells. BUB1 induced CIN through phosphorylation of KIF14 at serine1292 (Ser1292 ). Overexpression of the KIF14ΔSer1292 mutant was unable to facilitate the aggressiveness of ATC cells when compared with that of the wild type. Collectively, these findings demonstrate that the BUB1/KIF14 complex drives the aggressiveness of ATC by inducing CIN.

Adiponectin Inhibits the Progression of Obesity-Associated Papillary Thyroid Carcinoma Through Autophagy.

Obesity is a risk factor for the development of papillary thyroid cancer (PTC). However, the molecular mechanisms by which obesity promotes PTC are unclear. This study aims to identify adipokines that are linked to PTC progression. An adipokine antibody array was used to determine the serum levels of 40 adipokines in normal-weight and obese PTC patients. Enzyme-linked immunosorbent assay was used to determine the serum levels of adiponectin. Recombinant human adiponectin was produced by human adipose-derived stem cells and used to treat PTC cells. Cell proliferation and migration were evaluated using the CCK8 and Transwell assays. Bioinformatics analysis was used to predict mechanisms by which adiponectin affects PTC. Adipokines differentially expressed between normal-weight and obese patients showed a gender-dependent pattern. Obese PTC patients had a significantly lower serum adiponectin level than normal-weight patients, especially in female individuals. Adiponectin levels were negatively correlated with aggressive features of PTC, including tumor diameter > 1 cm, extrathyroidal extension, and lymph node metastasis. Recombinant human adiponectin inhibited the proliferation and migration of human PTC cells in vitro. Bioinformatics analysis identified adiponectin receptor 2 (ADIPOR2) and the autophagy pathway as possible mediators of adiponectin function in TC. In vitro experiments confirmed that adiponectin activated autophagy in PTC cells. These findings shed new lights into the role and mechanisms of adiponectin in TC pathogenesis. Adiponectin is involved in development of obesity-related PTC. Adiponectin can directly inhibit thyroid cancer growth and metastasis through the autophagy pathway.

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

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. 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. In summary, circNRCAM could up-regulate NRCAM by down-regulating miR-506-3p, thereby enhancing the biological behaviors of PTC cells.

Hypoxia expedites the progression of papillary thyroid carcinoma by promoting the CPT1A-mediated fatty acid oxidative pathway.

Hypoxia has been reported to promote the proliferation and migration of thyroid cancer, while the special mechanism was still unclear. HIF-1α/carnitine palmitoyl-transferase 1A (CPT1A) was found to be associated with papillary thyroid carcinoma (PTC) but the biological role of CPT1A in PTC was not explored. The effects of hypoxia and carnitine palmitoyl-transferase 1A (CPT1A) expression on PTC cells were determined by cell counting kit-8 assay, detection of oxidative stress, inflammation response and mitochondrial membrane motential (MMP). Oil Red O staining and the detection of free fatty acids were performed to assess the status of lipid metabolism. Flow cytometric analysis was performed to assess cell apoptosis. Quantitative polymerase chain reaction (qPCR) and western blot analysis were applied to investigate the expressions of CPT1A and HIF-1α and the molecules involved cell function. The expressions of CPT1A and HIF-1α were significantly increased in PTC cells with or without hypoxia treatment. CPT1A overexpression or silencing promoted or inhibited cell viability, and hypoxia further repressed cell viability. In addition, CPT1A overexpression alleviates hypoxia-induced increased oxidative stress, inflammation response and elevated MMP. CPT1A overexpression enhanced palmitic acid-induced decreased cell growth, enhanced the metabolic capacity of free fatty acid and suppressed cell apoptosis. Animal experiments showed that CPT1A overexpression promoted PTC tumor growth, reduced lipid deposition, oxidative stress and inflammation, as well as enhancing cell function indicators. However, CPT1A silencing showed the opposite effects both in vitro and in vivo. Hypoxia induces the high expression of HIF-1α/CPT1A, thereby reprogramming the lipid metabolism of PTC cells for adapting the hypoxia environment, meanwhile inhibiting the cell damage and apoptosis caused by oxidative stress.

TRMT13 inhibits the growth of papillary thyroid cancer by targeting ANAPC4.

The recently discovered gene TRMT13 encodes a type of RNA methylase and is a member of the CCDC family (also called CCDC76). Here, we delineate its role in papillary thyroid cancer (PTC). Bioinformatics analysis shows significant TRMT13 and ANAPC4 downregulation in PTC and reveals that the expression levels of both genes are linearly correlated. Subsequent analyses confirm that both TRMT13 and ANAPC4 expressions are downregulated in PTC tissues and that this change in expression has a significant impact on cancer diagnosis. We conduct assays on PTC cells subjected to TRMT13 and ANAPC4 silencing or overexpression to assess the biological effects of these genes. We also perform rescue experiments to validate the regulatory effects of TRMT13 on ANAPC4. A nude mouse tumor model is used to evaluate the effects of TRMT13 and ANAPC4 on PTC tumorigenesis. TRMT13 expression is decreased in PTC tissues and cell lines and is positively correlated with that of ANAPC4. Cell assays reveal that TRMT13/ANAPC4 attenuates the malignancy of PTC cells by restraining cell proliferation, migration and invasion, while rescue experiments corroborate that ANAPC4 is a downstream target of TRMT13. In the nude mouse xenograft model, both TRMT13 and ANAPC4 inhibit tumor growth, and TRMT13 and ANAPC4 expression levels are significantly associated with survival. Taken together, these findings lead to the conclusion that TRMT13 inhibits PTC growth via ANAPC4, indicating a new role of TRMT13 and providing insights into the tRNA methyltransferase and coiled-coil domain-containing protein families.

The Prognostic Value and Potential Immune Mechanisms of lncRNAs Related to Immunogenic Cell Death in Papillary Thyroid Carcinoma.

Long non-coding RNAs (lncRNAs) associated with immunogenic cell death (ICD) play a pivotal role in tumorigenesis and offer prognostic insights for papillary thyroid carcinoma (PTC) patients. This study delves into the impact of ICD-related lncRNAs on the prognosis of PTC. PTC samples were accessed from The Cancer Genome Atlas-Thyroid carcinoma database (TCGA-THCA) and consensus cluster analysis to elucidate the influence of ICD-related lncRNA expression. To gauge the prognostic significance of these lncRNAs, we developed a prognostic model. Additionally, we conducted GO and KEGG enrichment analyses, assessed immune cell infiltration (ICI) using CIBERSORT and ssGSEA, examined immune checkpoint expression, tumor mutation burden (TMB), tumor microenvironment (TME), T-cell dysfunction and exclusion (TIDE), TCIA, and drug sensitivity across various groups. A comprehensive suite of in vitro experiments, encompassing EdU labeling, wound scratch assays, Transwell assays, and flow cytometry, were conducted to elucidate the regulatory role of LINC00924 in two PTC cell lines, BCPAP and TPC1, transfected with LINC00924 overexpression plasmids. Two distinct clusters demonstrated varying TME, BRAF, NRAS, and ICI characteristics, suggesting potential immune mechanisms in PTC. Our prognostic model identified seven lncRNAs: SRRM2-AS1, AC008556.1, BHLHE40-AS1, EGOT, AL39066.1, LINC00924, and PICART1. The expression of ICD-related lncRNAs correlated with progression-free interval (PFI) in PTC patients. Overexpression of LINC00924 significantly reduced cell proliferation, migration, and invasion, while augmenting apoptosis in PTC cells. Our findings highlight the potential of ICD-related lncRNAs as prognostic biomarkers for PFI in PTC. In vitro experiments suggest a protective role of LINC00924 in PTC progression.

PAFAH1B3 Regulates Papillary Thyroid Carcinoma Cell Proliferation and Metastasis by Affecting the EMT.

Thyroid carcinoma (TC) is currently the prevalent type of endocrine malignancy worldwide, having an incidence of around 15.5 per 100,000 people. However, the underlying mechanisms of TC tumorigenesis remain to be further elucidated. Performing the database analyses, Platelet-activating factor acetylhydrolase 1B3 (PAFAH1B3) was found to be dysregulated in several carcinomas and might trigger tumor occurrence as well as the progression of TC. Clinicopathological information of patients from our local validated cohort and The Cancer Genome Atlas (TCGA) cohort also confirmed this hypothesis. Our present research showed that elevated expression of PAFAH1B3 has a close association with worse behavior in papillary thyroid carcinoma (PTC). We utilized the small interfering RNA to obtain the PAFAH1B3-transfected PTC cell lines, including BCPAP, FTC-133, and TPC-1, and then further examined their biological function in vitro. Furthermore, gene set enrichment analysis suggested that PAFAH1B3 is implicated with epithelial-mesenchymal transition (EMT). Afterward, the western blotting assays aimed at EMT-related proteins were performed. In short, our results revealed that silencing PAFAH1B3 could hinder the capabilities of proliferation, migration, and invasion of PTC cells. Increasing expression of PAFAH1B3 might be of quintessence with lymph node metastasis by triggering EMT in PTC patients.

Role of sodium/iodide symporter overexpression in inhibiting thyroid cancer cell invasion and stem cell maintenance by inhibiting the β-catenin/LEF-1 pathway

BackgroundIn thyroid cancers, a reduction in the expression of the sodium/iodide symporter (NIS) is observed concomitant with a diminution in cancer cell differentiation. The β-catenin/LEF-1 pathway emerges as a crucial regulatory pathway influencing the functional expression of NIS in human thyroid cancer cells. Further research is required to comprehensively elucidate the role of NIS overexpression in impeding the progression of thyroid cancer cells. MethodsHuman papillary thyroid carcinoma (PTC) cell lines, specifically PTC-1 and KTC-1, were subjected to Scratch and Transwell assays, colony formation, and tumor sphere formation tests to investigate invasion and migration, focusing on the impact of NIS overexpression. The assessment involved the use of western blot to analyze the expression levels of β-catenin, NIS, CD133, SRY-related HMG box2 (Sox2), lymphoid enhancer-binding factor 1 (LEF-1), NANOG, octamer-binding transcription factor 4 (Oct4), aldehyde dehydrogenase 1 family, member A1 (ALDH1A1), and epithelial cellular adhesion molecule (EpCAM). Statistical analysis was conducted using SPSS version 20.0, and the graphs were developed using GraphPad Prism 7 (GraphPad Software, Inc.). ResultsOur observations revealed that Nthy-ori-3-1 cell lines exhibited notably higher average expression levels of NIS, yet significantly lower levels of LEF-1 and β-catenin compared to PTC-1 and KTC-1 cell lines. Furthermore, the overexpression of β-catenin resulted in reduced binding of LEF-1 to NIF promotion but concurrently increased the expression of NIS. The downregulation of NIS markedly enhanced the expression of ALDH1A1, CD133, OCT4, Nanog, SOX2, and EpCam—all of which are targets within the Wnt/β-catenin signaling pathway. Conversely, the upregulation of NIS suppressed the expression of these proteins. Moreover, cells treated with β-catenin activators demonstrated an increased capability to form more spheroids and displayed heightened aggressiveness. Conversely, the NIS overexpression (OE) group exhibited suppressed abilities in invasion and colony formation. ConclusionThyroid cancer cells exhibit diminished expression of NIS, and the invasion and maintenance of stem cells in thyroid cancer cells were hindered by NIS OE through the inhibition of the β-catenin/LEF-1 pathway. Further research is warranted to comprehensively assess this outcome, which holds promise as a potential targeted treatment for thyroid cancer.