Apoptosis Of Papillary Thyroid Carcinoma Cells Research Articles

ACAP3 negatively regulated by HDAC2 inhibits the malignant development of papillary thyroid carcinoma cells

ArfGAP with coiled-coil, ankyrin repeat and PH domains 3 (ACAP3) level has been confirmed to be downregulated in papillary thyroid carcinoma (PTC). Histone deacetylase inhibitors (HDACIs) have therapeutic effects on PTC. Accordingly, this study probed into the potential relation of HDACIs and ACAP3 in PTC. Expressions of ACAP3 and histone deacetylase 2 (HDAC2) in PTC were investigated by quantitative real-time polymerase chain reaction (qRT-PCR). The relationship between HDAC2 and ACAP3 was predicted by Pearson analysis. Cell functional assays (cell counting kit-8, transwell, wound healing and flow cytometry assays) and rescue assay were carried out to determine the effects of HDAC2/ACAP3 axis on biological behaviors of PTC cells. Expressions of apoptosis-, epithelial-mesenchymal transition-, Protein Kinase B (AKT)-, and P53-related proteins were measured by Western blot. ACAP3 level was downregulated in PTC tissues and cells. ACAP3 overexpression (oe-ACAP3) suppressed viability, proliferation, migration and invasion of PTC cells, facilitated apoptosis, downregulated the expressions of Protein Kinase B (Bcl-2) and N-cadherin, upregulated the expressions of Bcl-2 associated protein X (Bax) and E-cadherin, diminished the p-AKT/AKT ratio and elevated the p-p53/p53 ratio; however, ACAP3 silencing or HDAC2 overexpression (oe-HDAC2) did the opposite. HDAC2 negatively correlated with ACAP3. The tumor-suppressing effect of oe-ACAP3 in PTC was reversed by oe-HDAC2. Collectively, ACAP3 negatively regulated by HDAC2 suppresses the proliferation and metastasis while facilitating apoptosis of PTC cells.

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.

CircRNA ITCH Inhibits Epithelial-Mesenchymal Transformation and Promotes Apoptosis in Papillary Thyroid Carcinoma via miR-106a-5p/JAZF1 Axis.

Circular RNA ITCH (circ-ITCH) is implicated in papillary thyroid carcinoma (PTC) development. Nevertheless, the more detailed molecular mechanism remains uncovered. The transcriptional level of circ-ITCH was tested via quantitative real-time PCR. Transwell assay was introduced to assess the migrative and invasive abilities of cells. RNA interference technology was employed to reduce the level of circ-ITCH as well as JAZF1 in PTC cells. Western blot assay was utilized to reveal the content of JAZF1 and proteins related to epithelial-mesenchymal transformation (EMT) progression. Circ-ITCH was downregulated in PTC tissues as well as cells. Overexpression of circ-ITCH suppressed EMT, migration, invasion, facilitated apoptosis in PTC cells, while silencing circ-ITCH exhibited reversed effects. Additionally, miR-106a-5p was the target of circ-ITCH and negatively regulated through circ-ITCH. MiR-106a-5p mimic partly eliminated the influences of overexpressed circ-ITCH in PTC cells. Moreover, JAZF1 could interact with miR-106a-5p, then it was regulated via circ-ITCH. Silencing JAZF1 partially counteracted the role of circ-ITCH in PTC cells progress. This study uncovered that circ-ITCH suppressed the development of PTC cells at least partly by mediating miR-106a-5p/JAZF1 network.

The inhibition of Beclin1-dependent autophagy sensitizes PTC cells to ABT737-induced death.

ABT737 is used as a specific BCL2 inhibitor, which can treat papillary thyroid carcinoma (PTC). However, the effect of ABT737 on PTC cell apoptosis is limited. Moreover, BCL2 inhibition causes the activation of Beclin1-dependent autophagy. Our study aimed to explore the effects of autophagy and Beclin1 on ABT737 efficacy in PTC. The experimental data showed that ABT737 synchronously enhanced autophagic activity and apoptosis level in PTC cells. ABT737 also promoted the dissociation of BCL2-Beclin1 and BCL2-Bax complexes. Autophagy inhibitors, Bafilomycin A1 and 3-MA, enhanced the inhibitory effect of ABT737 on the survival and function in PTC cells. Consistently, autophagy inhibition with Beclin1 pharmacological inhibitor (spautin-1) also enhanced the efficacy of ABT737. Additionally, ABT737 at low-dose promoted LC3 conversion in PTC cells, and did not affect PTC cell apoptosis and survival. However, The efficacy of low-dose of ABT737 in PTC cell apoptosis and survival was displayed with the addition of Bafilomycin A1, 3-MA or spautin-1. In conclusion, the limited role of ABT737 in PTC cell apoptosis is attributed to its promoting effect on Beclin1-dependent autophagy. Therefore, autophagy inhibition based on Beclin1 downregulation can enhance the sensitivity of PTC cells to ABT737-induced death.

CircPI4KA Overexpression Enhances Carcinogenesis and Glycolysis Metabolism in Papillary Thyroid Carcinoma by Causing the miR-1287-5p-Mediated NRP2 Expression Elevation.

Circular RNAs (circRNAs) are implicated in regulating the pathogenesis of papillary thyroid carcinoma (PTC). Herein, we aimed to investigate how circRNA phosphatidylinositol 4-kinase IIIα (circPI4KA, hsa_circ_0062389) functioned as an oncogene in PTC. CircPI4KA, microRNA-1287-5p (miR-1287-5p) and Neuropilin-2 (NRP2) level detection were completed by reverse transcription-quantitative polymerase chain reaction assay. Cell proliferation was assessed through Cell Counting Kit-8 assay, colony formation assay, and EdU assay. Transwell assay was used for detecting migration and invasion abilities. Cell migration was also determined by wound healing assay. Cell apoptosis was assessed using flow cytometry assay. The protein examination was performed using western blot. Glycolysis was evaluated via commercial kits. Dual-luciferase reporter assay and RNA immunoprecipitation assay were conducted for target analysis. The role of circPI4KA in vivo was explored and analyzed via tumor xenograft assay. CircPI4KA was significantly upregulated in PTC tissues and cells. Knockdown of circPI4KA suppressed proliferation, migration, invasion, glycolysis, and induced apoptosis of PTC cells. CircPI4KA interacted with miR-1287-5p in PTC cells. The antitumor function of circPI4KA downregulation was reversed by inhibition of miR-1287-5p. The miR-1287-5p directly targeted NRP2, and circPI4KA elevated the NRP2 expression by sponging miR-1287-5p. PTC progression was impeded by miR-1287-5p via targeting NRP2. Silencing circPI4KA inhibited tumor growth in vivo through the miR-1287-5p/NRP2 axis. The collective results revealed that circPI4KA induced the upregulation of NRP2 via sponging miR-1287-5p, thus acting as a carcinogenic factor in PTC.

Colchicine inhibits the proliferation and promotes the apoptosis of papillary thyroid carcinoma cells likely due to the inhibitory effect on HDAC1

Although the prognosis for papillary thyroid carcinoma (PTC) is generally good, a certain proportion of patients show recurrent or advanced disease, indicating the need for further development of targeted medications. The purpose of this study was to explore the interventional effects of colchicine on PTC and the potential mechanisms or targets. We obtained PTC-related targets from the database and colchicine targets by predicting them. We screened the common targets of colchicine and the PTC-related target histone deacetylase 1 (HDAC1) and verified through molecular docking that colchicine has a good affinity for HDAC1, i.e., colchicine may act on PTC by affecting HDAC1. We then used CCK-8, colony formation, mitochondrial membrane potential and apoptosis assays to confirm that colchicine could inhibit the proliferation and promote the apoptosis of PTC cells and verified by RT‒qPCR, Western blot, and cellular immunofluorescence assays that colchicine could inhibit the expression of HDAC1 in PTC cells. The cytotoxicity and inhibitory effect of colchicine on HDAC1 in PTC cells was stronger than that in normal thyroid cells. We then applied an HDAC1 inhibitor, pyroxamide, to verify that inhibition of HDAC1 inhibits proliferation and promotes apoptosis in PTC cells. Therefore, we conclude that colchicine can inhibit the proliferation and promote the apoptosis of PTC cells likely due to its inhibitory effect on HDAC1. This finding implies that colchicine may be helpful for therapeutic intervention in PTC and that HDAC1 may be a promising clinical therapeutic target.

MicroRNA-142-3P suppresses the progression of papillary thyroid carcinoma by targeting FN1 and inactivating FAK/ERK/PI3K signaling

ObjectivesmiR-142–3P is a tumor suppressor in various malignant cancers. However, the function of miR-142–3P in papillary thyroid carcinoma (PTC) remains to be elucidated. The aim of this study was to explore the function and mechanism of miR-142–3P in PTC. MethodsReal Time Quantitative PCR (RT-qPCR) was used to assess the expression of miR-142–3P and Fibronectin 1 (FN1) in PTC. The correlation between FN1 and miR-142–3P expression was analyzed by Spearman's correlation analysis. Cell Counting Kit 8 (CCK8), 5-ethynyl-2′-deoxyuridine (EDU) assay, cell migration and invasion assay and wound healing measures evaluated the effect of miR-142–3P and FN1 on cell proliferation, migration and invasion. Dural Luciferase reported gene assay evaluated the interaction between miR-142–3P and 3′ untranslated region (UTR) of FN1. The Epithelial-Mesenchymal-Transition (EMT) and apoptosis related marker genes were measured using western blot analysis (WB). ResultsmiR-142–3P was significantly decreased in both PTC specimens and relevant cell lines. Functionally, miR-142–3P inhibited cell proliferation, migration, invasion and EMT, and induced the cell apoptosis in PTC. In addition, miR-142–3P bound directly with 3’ UTR of FN1 and negatively regulated the expression of FN1 in PTC. FN1 expression is elevated in PTC, and its aberrant high correlated with declines in recurrence-free survival (RFS). Moreover, FN1 promoted cell proliferation, migration, invasion and EMT, induced cell apoptosis in PTC cells. Depletion of FN1 rescues the effect of miR-142–3P inhibitor on cell proliferation, invasion, apoptosis and EMT via inactivating Focal Adhesion Kinase (FAK)/Extracellular Signal-Regulated Kinase (ERK) / Phosphoinostide 3-kinase (P13K) signaling. ConclusionmiR-142–3P suppressed cell proliferation, migration, invasion and EMT through modulating FN1/FAK/ERK/PI3K signaling in PTC, suggesting it as a potential therapeutic target for PTC.

MiR-204-5p-targeted AP1S2 is necessary for papillary thyroid carcinoma

MiR-204-5p, as a tumour suppressor, has been found in several cancers. However, whether miR-204-5p is involved in papillary thyroid carcinoma (PTC) has not yet been investigated. In this study, we identified miR-204-5p as a down-regulated miRNA in PTC tissues, unveiling that the levels of miR-204-5p in serum of patients with PTC were linked to PTC risk, and that the expression in patients concomitant with both PTC and benign lesions was much lower than that in patients only with PTC. Furthermore, we documented that miR-204-5p inhibited proliferation, migration, invasion, and cell cycle progression and triggered apoptosis of PTC cells via cell biology experiments. Finally, we identified that AP1S2 was a target of miR-204-5p using RNA-seq, iTRAQ, and bioinformatics prediction. Overall, miR-204-5p functions as a suppressor for PTC pathogenesis via the miR-204-5p/AP1S2 axis.

SKP2 Contributes to AKT Activation by Ubiquitination Degradation of PHLPP1, Impedes Autophagy, and Facilitates the Survival of Thyroid Carcinoma.

Papillary thyroid carcinoma (PTC) is the most common subtype of thyroid carcinoma. Despite a good prognosis, approximately a quarter of PTC patients are likely to relapse. Previous reports suggest an association between S-phase kinase-associated protein 2 (SKP2) and the prognosis of thyroid cancer. SKP1 is related to apoptosis of PTC cells; however, its role in PTC remains largely elusive. This study aimed to understand the expression and molecular mechanism of SKP2 in PTC. SKP2 expression was upregulated in PTC tissues and closely associated with clinical diagnosis. In vitro and in vivo knockdown of SKP2 expression in PTC cells suppressed cell growth and proliferation and induced apoptosis. SKP2 depletion promoted cell autophagy under glucose deprivation. SKP2 interacted with PH domain leucine-rich repeat protein phosphatase-1 (PHLPP1), triggering its degradation by ubiquitination. Furthermore, SKP2 activates the AKT-related pathways via PHLPP1, which leads to the cytoplasmic translocation of SKP2, indicating a reciprocal regulation between SKP2 and AKT. In conclusion, the upregulation of SKP2 leads to PTC proliferation and survival, and the regulatory network among SKP2, PHLPP1, and AKT provides novel insight into the molecular basis of SKP2 in tumor progression.

Circ_0002111 modulates the growth process of papillary thyroid carcinoma cells by targeting the miR-363-3p/HMGB1 axis.

Previous studies have suggested that circular RNAs (circRNAs) are engaged in the progression of papillary thyroid carcinoma (PTC). However, the mechanism of circ_0002111 in PTC is still unclear. In this study, quantitative real-time PCR was carried out to measure the expressions of circ_0002111, microRNAs (miRNAs) and high-mobility group box 1 (HMGB1). Immunohistochemistry assay and western blot were applied for the determination of protein levels. The assays of 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2-H-tetrazolium bromide and thymidine analog 5-ethynyl-2'-deoxyuridine were deployed to assess PTC cell viability and proliferation, respectively. Besides, the capacities of cell apoptosis, invasion and angiogenesis were determined by flow cytometry, transwell and tube formation assays, respectively. Moreover, the interaction between miR-363-3p and circ_0002111 or HMGB1 was confirmed using a dual-luciferase reporter assay. Lastly, we established a xenograft model for the examination of the function of circ_0002111 in vivo. It was found that the expression of circ_0002111 was enhanced in PTC tissues and cells. Silencing circ_0002111 apparently retarded the viability, proliferation, invasion and tube formation, as well as expedited the apoptosis of PTC cells. Besides, circ_0002111 knockdown impeded the growth of the tumor in vivo. For mechanism analysis, circ_0002111 adjusted the expression of HMGB1 by sponge adsorption of miR-363-3p. Moreover, miR-363-3p inhibitor regained the influence of cellular malignant phenotype caused by circ_0002111 knockdown. Additionally, miR-363-3p overexpression impacted the cell functions by targeting HMGB1 in PTC. Thus, silencing circ_0002111 constrained the progression of PTC by the miR-363-3p/HMGB1 axis, which perhaps provided a novel idea of the therapeutic in PTC.

Overexpression of ST7-AS1 Enhances Apoptosis and Inhibits Proliferation of Papillary Thyroid Carcinoma Cells Via microRNA-181b-5p-Dependent Inhibition Tripartite Motif Containing 3.

Long non-coding RNAs (lncRNAs) are of great significance in the pathogenesis and progression of papillary thyroid carcinoma (PTC). LncRNA tumorigenicity 7 antisense RNA 1 (ST7-AS1) is a newly identified lncRNA serving as an oncogene or tumor suppressor in different tumors; however, the role of ST7-AS1 in PTC remains completely unknown. In this study, ST7-AS1 was mainly distributed in the cytoplasm of PTC cells and presented reduced expression in THCA tumors and PTC cell lines. Functional experiments revealed that overexpressed ST7-AS1 inhibited the viability and proliferation of PTC cells, whereas accelerated the apoptosis of PTC cells. The expression of miR-181b-5p was upregulated and it bound with ST7-AS1 in PTC cells. Moreover, TRIM3 exhibited downregulated expression level in PTC cells and ST7-AS1 elevated TRIM3 expression via harboring miR-181b-5p. Rescue experiments illuminated that knockdown of TRIM3 reversed ST7-AS1 overexpression-induced promotion on PTC cell proliferation and suppression on PTC cell apoptosis. Overall, overexpression of ST7-AS1 enhances apoptosis and represses proliferation of PTC cells via targeting the miR-181b-5p/TRIM3 axis, which may help broaden the horizon and establish the foundation to develop therapeutic strategies for PTC in the future.

The circ_FAM53B-miR-183-5p-CCDC6 axis modulates the malignant behaviors of papillary thyroid carcinoma cells.

Papillary thyroid carcinoma (PTC) is a common thyroid malignancy. Circular RNAs (circRNAs) have been implicated in the development of PTC. Here, we explored the function and mechanism of circRNA family with sequence similarity 53, member B (circ_FAM53B) in PTC pathogenesis. Circ_FAM53B, microRNA (miR)-183-5p and coiled-coil domain containing 6 (CCDC6) levels were gauged by quantitative reverse transcription polymerase chain reaction (qRT-PCR) or Western blotting. The direct relationship between miR-183-5p and circ_FAM53B or CCDC6 was verified by dual-luciferase reporter and RNA immunoprecipitation (RIP) assays. Our data showed that circ_FAM53B expression was reduced in PTC tissues and cells. Circ_FAM53B expression restrained proliferation, migration, and invasion and triggered apoptosis of PTC cells, as well as hindered HUVEC tube formation. Circ_FAM53B repressed miR-183-5p expression. MiR-183-5p re-expression reversed the effects of circ_FAM53B on cell behaviors. MiR-183-5p targeted and inhibited CCDC6, and circ_FAM53B upregulated CCDC6 through miR-183-5p competition. MiR-183-5p knockdown repressed cell proliferation, migration, invasion, and tube formation and facilitated apoptosis by upregulating CCDC6. Furthermore, circ_FAM53B reduced tumor growth in vivo. Collectively, our findings suggest that circ_FAM53B affects PTC cell biological behaviors via the miR-183-5p-CCDC6 axis.

Long non-coding RNA nuclear enriched abundant transcript 1 (NEAT1) modulates inhibitor of DNA binding 1 (ID1) to facilitate papillary thyroid carcinoma development by sponging microRNA-524-5p

ABSTRACT Long non-coding RNA (lncRNA) nuclear-enriched abundant transcript 1 (NEAT1) exerts a pro-oncogenic role in several cancers, whereas its underlying regulatory mechanism in papillary thyroid carcinoma (PTC) progression remains unknown. This research mainly explored the roles of NEAT1 in PTC development. Quantitative real-time polymerase-chain reaction (qRT-PCR) was applied to measure NEAT1, miR-524-5p, and inhibitor of DNA binding 1 (ID1) expression in PTC tissues and cells. Western blot was conducted for detecting the protein levels. MTT, transwell, and flow cytometry assays were applied to assess cell proliferation, metastasis, and apoptosis in PTC cells in vitro. The PTC xenograft tumor model was used for investigating the role of NEAT1 in vivo. Dual-luciferase reporter assay was utilized for confirming the interaction between miR-524-5p and NEAT1 or ID1. In PTC tissues and cells, NEAT1 was significantly up-regulated. NEAT1 silencing blocked cell proliferation, metastasis, and facilitated apoptosis in vitro and impeded xenograft tumor growth in vivo. Bioinformatics prediction revealed the existence of binding sites between NEAT1 and miR-524-5p. Besides, ID1 was confirmed as a direct target to miR-524-5p, and the enhancement of ID1 reversed the regulation of miR-524-5p upregulation on cell progression. In addition, NEAT1 promoted PTC development by regulating ID1 expression via sponging miR-524-5p in PTC. In summary, we demonstrate that NEAT1 advanced the process of PTC by miR-524-5p/ID1 axis, which may enhance our comprehension of PTC pathogenesis.

NOD1 activation promotes cell apoptosis in papillary thyroid cancer

BackgroundNOD1 can promote or inhibit different types of cancers, suggesting that NOD1 functions in the progression of cancers dependent on the tumour environment. However, the expression and mechanisms of NOD1 during papillary thyroid carcinoma (PTC) progression remain unclear. MethodsTo investigate the role of NOD1 in PTC development and apoptosis, we detected NOD1 expression in three cell lines and surgical specimens from patients with PTC using immunohistochemistry, quantitative real-time PCR (Q-PCR) and Western blotting; we studied the biological functions of NOD1 by loss-of-function analysis of TPC-1 and BCPAP cells and the effect of NOD1 on the progression of PTC in terms of cell proliferation and apoptosis induced by tumour necrosis factor alpha (TNF-α), Fas ligand (Fas L), tumour necrosis factor-related apoptosis-inducing ligand (TRAIL) or Ala-γGlu-diaminopimelic acid (TriDAP) in the presence of cycloheximide (CHX) and determined its underlying molecular mechanism using PTC cell lines in vitro and mouse xenograft models in vivo. ResultsIncreased expression of NOD1 is correlated with an improved prognosis in thyroid cancer patients. We also found that NOD1 expression was markedly upregulated in PTC cells compared to normal epithelial cells. NOD1 knockdown significantly promoted the proliferation of PTC cells in vitro, while activation of NOD1 signalling promoted PTC cell apoptosis; NOD1-induced apoptosis depends on the activation of caspase-3 and caspase-9 although the RIP2/TAK1 and MAPK pathways in PTC cells. ConclusionsThis study demonstrates that NOD1 is a predictive biomarker for PTC and that PTC cell apoptosis is induced by activation of NOD1 via the RIP2/TAK1 and MAPK pathways. The above results may provide a new perspective on targeting NOD1 signalling for the treatment of PTC, which deserves further investigation.

Platycodin D inhibits the malignant progression of papillary thyroid carcinoma by NF-κB and enhances the therapeutic efficacy of pembrolizumab.

Papillary thyroid carcinoma (PTC) is the most common pathological type of thyroid cancer. Studies have shown that platycodin D has several pharmacological effects like anti-inflammatory, immunomodulatory, and anti-tumor effects, while the effect and mechanism of platycodin D on PTC are still unclear. This study was designed to investigate the effects of platycodin D on PTC by a series of in vitro and in vivo experiments. The results revealed that platycodin D inhibits PTC cell viability and clonal levels and affects PTC cell cycle. Platycodin D promotes apoptosis in PTC cells. Furthermore, it inhibits the activation of NF-κB signaling pathway and affects cell growth. Platycodin D inhibits PD-L1 expression and enhances the effect of pembrolizumab on PTC cells. In conclusion, platycodin D can effectively block the progression of PTC through the NF-κB signaling pathway, accompanied by cell cycle arrest and enhanced cell apoptosis. In vitro and in vivo, platycodin D was shown to enhance pembrolizumab's sensitivity to PTC. Platycodin D is a promising monomer for therapy of PTC, providing references for future research on PTC treatment.

Circ_0059354 aggravates the progression of papillary thyroid carcinoma by elevating ARFGEF1 through sponging miR-766-3p.

Circular RNAs (circRNAs) have been identified as vital players in tumors, including papillary thyroid carcinoma (PTC). The purpose of this study is to explore the functions of circ_0059354 on PTC development. Quantitative real-time polymerase chain reaction (qRT-PCR) was conducted to examine the levels of circ_0059354, microRNA-766-3p (miR-766-3p) and ADP ribosylation factor guanine nucleotide exchange factor 1 (ARFGEF1). Cell Counting Kit-8 (CCK-8) assay and colony formation assay were proceeded for cell proliferation ability. Transwell assay was conducted for cell migration and invasion. Tube formation assay was employed to examine the angiogenesis ability. Flow cytometry analysis was adopted for cell apoptosis. Western blot assay was conducted for protein levels. Dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay were utilized to verify the relationships among circ_0059354, miR-766-3p and ARFGEF1. The murine xenograft model was constructed to analyze the function of circ_0059354 in vivo. Circ_0059354 level was abnormally increased in PTC tissues and cells. Functionally, circ_0059354 silencing suppressed cell proliferation, migration, invasion and angiogenesis and facilitated apoptosis in PTC cells. Circ_0059354 was identified to sponge miR-766-3p, which directly targeted ARFGEF1. Moreover, circ_0059354 directly targeted miR-766-3p to positively regulated ARFGEF1 expression. MiR-766-3p inhibition reversed circ_0059354 knockdown-mediated effect of PTC cell malignant behaviors. Overexpression of miR-766-3p restrained the malignant behaviors of PTC cells, whereas ARFGEF1 elevation reversed the effects. Additionally, circ_0059354 deficiency blocked tumor growth in vivo. Circ_0059354 served as an oncogene in PTC progression through regulating miR-766-3p/ARFGEF1 axis.

Circ_0067934 promotes the progression of papillary thyroid carcinoma cells through miR-1301-3p/HMGB1 axis.

Papillary thyroid carcinoma (PTC) is the most prevalent form of thyroid cancer (TC). There is increasing evidence that circular RNAs play a role in the tumorigenesis of PTC. The aim of our study was to evaluate the potential function of circ_0067934 in PTC and the underlying molecular mechanism. In our study, cell viability assay, quantitative real-time PCR (qRT-PCR), colony formation assay, flow cytometry, wound-healing assay, Transwell invasion assay, western blot, soft agar assay, RNA immunoprecipitation (RIP), dual-luciferase reporter assay, immunohistochemical (IHC) staining, and tumor xenograft formation were conducted to evaluate the effects of circ_0067934 in PTC cells. We found that circ_0067934 was upregulated in PTC tissues and cell lines. Knockdown of circ_0067934 inhibited growth, colony formation, migration, invasion, EMT, and tumor xenograft growth, and induced apoptosis of PTC cells. Moreover, circ_0067934 acted as a molecular sponge for miR-1301-3p, and depletion of miR-1301-3p abrogated the effects of circ_0067934 knockdown in PTC cells. In addition, HMGB1 was a target of miR-1301-3p, and miR-1301-3p overexpression inhibited the malignant effects of PTC cells via suppressing HMGB1. Furthermore, knockdown of circ_0067934 suppressed HMGB1 expression, PI3K/Akt, and MAPK activation by sponging miR-1301-3p. In nude mice, circ_0067934 depletion repressed tumor xenograft growth of PTC cells. In conclusion, our results provided a novel insight into circ_0067934 in the tumorigenesis and progression of PTC. circ_0067934 might be a prognostic marker or therapeutic target for PTC treatment.

Knockdown of ANXA10 inhibits proliferation and promotes apoptosis of papillary thyroid carcinoma cells by down-regulating TSG101 thereby inactivating the MAPK/ERK signaling pathway.

Annexin A10 (ANXA10) is a member of annexin A and has been reported to highly express in papillary thyroid carcinoma (PTC) tissues. Tumor susceptibility gene 101 (TSG101) also plays a role in PTC and is predicted to bind to ANXA10. This study intended to investigate whether ANXA10 could regulate PTC via binding to ANXA10. The expression of ANXA10 and TSG101 in normal thyroid follicular epithelial cell line and several PTC cell lines was analyzed using RT-qPCR and western blotting assays. Subsequently, PTC cell line BCPAP was silenced with ANXA10 followed by TSG101 overexpression or not, and then cell proliferation, apoptosis and mitogen-activated protein kinase (MAPK) signaling expression were assessed via MTT, colony formation, immunofluorescence staining, Tunel staining and western blotting assays. Besides, the interaction between ANXA10 and TSG101 was validated using Co-immunoprecipitation assay. ANXA10 and TSG101 expressions were up-regulated in PTC cell lines. ANXA10 silence inhibited proliferation, promoted apoptosis and inactivated MAPK/ extracellular regulated protein kinases (ERK) signaling pathway of BCPAP cells. Additionally, ANXA10 could bind to TSG101 and regulate its expression. However, the above effects of ANXA10 silence on BCPAP cells were all blocked by TSG101 overexpression. ANXA10 inhibited proliferation and promoted apoptosis of PTC cells via binding to TSG101, and these actions may depend on down-regulating MAPK/ERK pathway expression.

FK506-binding protein 5 promotes the progression of papillary thyroid carcinoma.

ObjectiveTo detect the expression of FK506-binding protein 5 (FKBP5) in human papillary thyroid carcinoma (PTC) tissues, and explore its possible role in the progression of PTC.MethodsFKBP5 expression levels were assessed in 115 PTC tissues and corresponding normal tissues by immunohistochemistry. We also examined the correlations between FKBP5 expression and clinicopathological factors and survival in 75 patients with PTC. The effects of FKBP5 on the proliferation and apoptosis of PTC cells were detected by colony-formation, MTT, and flow cytometry assays, respectively. We further investigated the effects of FKBP5 on tumor growth in mice.ResultsWe revealed high expression levels of FKBP5 in human PTC tissues compared with normal tissues. Furthermore, high FKBP5 expression was associated with an increased incidence of intraglandular dissemination, and lower overall and progression-free survival. FKBP5 depletion remarkably suppressed the proliferation and induced apoptosis of PTC cells in vitro. FKBP5 further contributed to the growth of PTC tumors in mice.ConclusionsThe results of this study demonstrated the potential involvement of FKBP5 in the progression of PTC, and confirmed FKBP5 as a novel therapeutic target for PTC treatment.

LncRNA DUXAP8 inhibits papillary thyroid carcinoma cell apoptosis via sponging the miR‑20b‑5p/SOS1 axis.

Papillary thyroid carcinoma (PTC) is the most common type of cancer in the endocrine system. Long non‑coding RNAs (lncRNAs) are associated with PTC progression. Therefore, the present study aimed to identify a novel lncRNA involved in PTC. Herein, dysregulated lncRNAs were analyzed in The Cancer Genome Atlas (TCGA)‑thyroid cancer (THCA) data. Furthermore, the association between double homeobox A pseudogene 8 (DUXAP8) gene expression and disease stage, and prognosis of patients with PTC was evaluated using the GEPIA online database, while the correlation between DUXAP8 expression and the clinicopathological characteristics of patients with PTC was analyzed by Chi‑square test. In addition, the biological effect of DUXAP8 expression on cell proliferation and apoptosis was also investigated. The protein and mRNA/microRNA (miRNA)/lncRNA expression levels were assessed by western blot analysis and reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR), respectively. The interaction between miR‑20b‑5p and DUXAP8 was verified using bioinformatics analysis, RNA RIP assay, dual luciferase reporter assay, western blot analysis and RT‑qPCR. The analysis of the TCGA‑THCA data revealed that DUXAP8 was one of the most significantly upregulated lncRNAs in PTC. This finding was further confirmed in tissues from patients with PTC. Increased DUXAP8 expression was associated with higher grade and poorer prognosis in patients with PTC. In PTC cell lines, silencing of DUXAP8 expression with small interfering RNA‑DUXAP8 (si‑DUXAP8) induced cell apoptosis and attenuated cell proliferation. Additionally, transfection of PTC cells with si‑DUXAP8 decreased the phosphorylation levels of MEK1/2 and ERK1/2, as well as downregulated the expression of son of sevenless1(SOS1), cyclinD1(CCND1) and c‑Myc. The results of the present study also revealed that miR‑20b‑5p could directly target DUXAP8. DUXAP8 expression was positively associated with that of SOS1, c‑Myc and CCND1 in the TCGA‑THCA data, and DUXAP8 level was positively correlated with that of SOS1 in PTC tumor tissues. Finally, transfection of PTC cells with the SOS1 overexpression plasmid, pcDNA3.1‑SOS1, rescued the effects of si‑DUXAP8 on cell proliferation and apoptosis. The present study was the first to identify DUXAP8 as a novel upregulated lncRNA in PTC, and provided new insights in understanding the effect of the lncRNA‑miRNA‑mRNA network in PTC.