Follicular Cell Line Research Articles

MicroRNA-124-3p inhibits tumourigenesis by targeting mitogen-activated protein kinase 4 in papillary thyroid carcinoma.

The study aimed to investigate the role of miR-124-3p and its potential molecular mechanism in papillary thyroid cancer (PTC). The expression of miR-124-3p and mitogen-activated protein kinase 4 (MAP2K4) in human thyroid follicular epithelial cell line (NTHY-ORI3-1) and human papillary thyroid carcinoma cell lines (SW1736, BCPAP, TPC-1 and K1) was measured by RT-qPCR. Cell proliferation was measured by CCK-8, while cell cycle and apoptosis rate were measured by flow cytometry. Invasive ability and migrative ability were measured by transwell assay and wound healing assay, respectively. Western blot was used to detect the levels of relative proteins. In vivo, TPC-1 cells transfected with miR-124-3p mimic were subcutaneously injected into the flank of the mice to form tumour. After successful modelling, mice were divided into two groups (n = 10): Control group and miR-124-3p mimic group. The present study showed that miR-124-3p was lowly expressed, while MAP2K4 was highly expressed in PTC cell lines. Besides, miR-124-3p targeted MAP2K4 and negatively regulated MAP2K4 in TPC-1 cells. In addition, miR-124-3p inhibited the proliferation and motility, and induced apoptosis and cell cycle arrest of TPC-1 cells by inactivating MAP2K4/JNK/JunD pathway. Furthermore, miR-124-3p inhibited tumour formation by downregulating MAP2K4 level in vivo. In conclusion, the study provided a novel molecular mechanism of miR-124-3p in the progress of PTC. SIGNIFICANCE OF THE STUDY: Papillary thyroid cancer (PTC) is the most important pathological type of thyroid cancer, accounting for 80% of thyroid cancer. miR-124-3p exhibited significant inhibitory role in the transformation and development of malignant tumours. However, in PTC, the roles and its potential molecular mechanism are unclear. Here, the study investigated the roles of miR-124-3p in the progress of PTC and its potential molecular mechanism. We found that miR-124-3p inhibited the proliferation and motility, and induced apoptosis and cell cycle arrest in PTC cells. This study provided a novel molecular mechanism of miR-124-3p in the progress of PTC.

Caveolin-1 Regulates CCL5 and PPARγ Expression in Nthy-ori 3-1 Cells: Possible Involvement of Caveolin-1 and CCL5 in the Pathogenesis of Hashimoto's Thyroiditis.

Hashimoto's thyroiditis (HT) is characterized by lymphocytic infiltration of the thyroid parenchyma, which ultimately leads to tissue destruction and loss of function. Caveolin-1 (Cav-1) is an essential structural constituent of lipid rafts in the plasma membrane of cells and is reported to be significantly reduced in thyrocytes from HT patients. However, the mechanism of Cav-1 involvement in HT pathogenesis is still largely unclear. Cav-1 expression in thyroid tissues from HT patients and euthyroid nodular goiter tissues was detected by immunohistochemistry staining. Cav-1 knockdown and overexpression were constructed by lentiviral transfection in the human thyroid follicular epithelial cell (TFC) line of Nthy-ori 3-1. The mRNA expression levels of chemokines in TFCs were determined by quantitative real-time PCR (qPCR). Cav-1 and peroxisome proliferator-activated receptor gamma (PPARγ) levels were analysed by qPCR and Western blot analysis. The migration ability of peripheral blood mononuclear cells (PBMCs) was detected by the Transwell assay. In this study, Cav-1 and PPARγ expression was reduced in the thyroid tissues from HT patients. In vitro experiments showed that the expressions of chemokine (C-C motif) ligand 5 (CCL5) and migration of PBMCs were markedly increased, while the level of PPARγ was significantly decreased after the lentivirus-mediated knockdown of Cav-1 in Nthy-ori 3-1 cells. Interestingly, pioglitazone, a PPARγ agonist, not only upregulated PPARγ and Cav-1 proteins significantly, but also effectively reversed the Cav-1-knockdown-induced upregulation of CCL5 in Nthy-ori 3-1 cells and reduced the infiltration of lymphocytes. The inhibition of Cav-1 upregulated the CCL5 expression and downregulated the PPARγ expression in TFC while pioglitazone, a PPARγ agonist, reversed the detrimental consequence. This outcome might be a potential target for the treatment of lymphocyte infiltration into the thyroid gland and HT development.

FoxP3 promotes lymph node metastasis in patients with papillary thyroid carcinoma complicated with Hashimoto’s thyroiditis

BackgroundTo investigate the effect of Treg cells on patients with PTC complicated with HT.MethodsWe collected thyroid fresh tissue of human after surgery, paraffin tissue and serum samples (cancer tissue which was diagnosed by pathology). Analysed the expression of nuclear specific marker gene FoxP3 in Treg cells by Envision immunohistochemical staining. Transwell cell chamber was used to simulate the co-action environment of umbilical cord blood initial T lymphocytes and thyroid papillary carcinoma cells (TPC-1and K1). Compared with human normal thyroid follicular epithelial cell line Nthy-ori 3-1. Flow cytometry was used to detect the proportion of Treg cells (CD4+CD25+CD127−/CD4+CD25+%) at 0, 24, 36, 48, 60 h after co-administration of thyroid papillary carcinoma cell lines (TPC-1 and K1) and umbilical cord blood initial T lymphocytes. The expression of FoxP3 protein in co-acting T lymphocytes was detected by Western blot.ResultsThe results showed that the positive expression of FoxP3 in the tumor microenvironment of PTC patients with or without HT promoted lymph node metastasis of tumors and played a role in inhibiting tumor immunity. PTC cancer cells could induce initial T lymphocyte differentiating into Treg cells. At 36 h, the ratio of Th17 cells and Treg cells which were differentiated was the highest. The balance of Th17/Treg was significantly biased toward Th17. The proportion of FoxP3 induced by K1 cell line with lymph node metastasis was higher than that of TPC-1 cell line without lymph node metastasis.ConclusionsFoxP3 could promote lymph node metastasis to inhibit tumor immunity by dysregulation of Th17/Treg balance in PTC patients complicated with HT.

Evaluation of potential sodium-iodide symporter (NIS) inhibitors using a secondary Fischer rat thyroid follicular cell (FRTL-5) radioactive iodide uptake (RAIU) assay.

The Fischer rat thyroid follicular cell line (FRTL-5) endogenously expresses the sodium-iodide symporter (NIS) and has been used to identify environmental chemicals that perturb thyroid hormone homeostasis by disruption of NIS-mediated iodide uptake. Previously, a high-throughput radioactive iodide uptake (RAIU) screening assay incorporating the hNIS-HEK293T-EPA cell line was used to identify potential human NIS (hNIS) inhibitors in 1028 ToxCast Phase I (ph1_v2) and Phase II chemicals. In this study, the FRTL-5 cell line was evaluated and applied as a secondary RAIU assay coupled with cell viability assays to further prioritize highly active NIS inhibitors from the earlier screening. Assay validation with ten reference chemicals and performance assessment by chemical controls suggest the FRTL-5 based assays are robust and highly reproducible. Top-ranked chemicals from the ToxCast screening were then evaluated in both FRTL-5 and hNIS RAIU assays using newly sourced chemicals to strengthen the testing paradigm and to enable a rat vs. human species comparison. Eighteen of 29 test chemicals showed less than 1 order of magnitude difference in IC50 values between the two assays. Notably, two common perfluorinated compounds, perfluorooctanesulfonic acid (PFOS) and perfluorohexane sulfonate (PFHxS), demonstrated strong NIS inhibitory activity [IC50 -6.45 (PFOS) and -5.70 (PFHxS) log M in FRTL-5 RAIU assay]. In addition, several chemicals including etoxazole, methoxyfenozide, oxyfluorfen, triclocarban, mepanipyrim, and niclosamide also exhibited NIS inhibition with minimal cytotoxicity in both assays and are proposed for additional testing using short-term in vivo assays to characterize effects on thyroid hormone synthesis.

Tissue factor pathway inhibitor 2 suppresses the growth of thyroid cancer cells through by induction of apoptosis.

Tissue factor pathway inhibitor 2 (TFPI-2) has been recently identified as a tumor suppressor gene in several human cancers, whereas its role in thyroid cancer has been unclear. The TFPI-2 protein level in thyroid cancer tissues and cell lines (8305C and B-CPAP) were examined using immunohistochemistry and immunoblotting. The TFPI-2 promoter methylation was examined using methylation-specific polymerase chain reaction (MSP). Lentivirus containing TFPI-2 cDNA (Lenti-TFPI-2) was constructed to elevate TFPI-2 expression in 8305C and B-CPAP cells. The effects of Lenti-TFPI-2 on cell proliferation in vitro and in vivo were evaluated by MTT assay and mouse xenograft model. Annexin V/PI double staining assay was performed to detect the effect of Lenti-TFPI-2 on cell apoptosis. TFPI-2 protein level were decreased in cancer tissues and lymph node metastasis, and TFPI-2 protein level is positively associated with survival time. The promoter of TFPI-2 is hypermethylated in cancer tissues. TFPI-2 mRNA and protein levels were abundant in normal human thyroid follicular cell line Nthy-ori 3-1 cells, whereas they were decreased in 8305C and B-CPAP cells. pcDNA-TFPI-2 elevated TFPI-2 mRNA and protein in 8305C and B-CPAP cells. TFPI-2 overexpression suppressed proliferation and induced apoptosis of 8305C and B-CPAP cells. TFPI-2 inactivation may play a role in thyroid cancer tumorigenesis and development. TFPI-2 overexpression suppressed cell proliferation through induction of cell apoptosis, suggesting that TFPI-2 may serve as a novel and effective target for thyroid cancer therapy.

The TUSC2 Tumour Suppressor Inhibits the Malignant Phenotype of Human Thyroid Cancer Cells via SMAC/DIABLO Protein.

Thyroid carcinoma is the most common endocrine cancer and includes different forms. Among these, anaplastic thyroid carcinoma (ATC) is the rarest but the most lethal subtype, compared to papillary thyroid carcinoma (PTC) which shows an overall good prognosis. We have previously showed that Tumor Suppressor Candidate 2 (TUSC2), a known tumour suppressor gene, is downregulated in human PTC and ATC compared to normal thyroid samples. The aim of this study was to gain insight into the molecular mechanisms induced by TUSC2 in thyroid cancer cells. Here, we stably transfected TUSC2 in papillary (TPC-1) and in anaplastic (8505C) thyroid cancer cell lines and studied its effects on several biological processes, demonstrating that TUSC2 overexpression decreased thyroid cancer cell proliferation, migration and invasion. Through the proteome profiler apoptosis array, we observed that TUSC2 increased sensitivity to apoptosis by increasing the SMAC/DIABLO and CYTOCHROME C proteins. On the other hand, transient silencing of TUSC2, by siRNA, in an immortalized thyroid follicular epithelial cell line (Nthy-ori 3-1) showed the opposite effect. Finally modulation of SMAC/DIABLO partially rescued the biological effects of TUSC2. Thus, our data highlight a tumour suppressor role of TUSC2 in thyroid carcinogenesis, suggesting that it could be a promising target and biomarker for thyroid carcinoma.

Silencing NEAT1 suppresses thyroid carcinoma via miR-126/NEAT1/VEGFA axis.

The incidence of papillary thyroid carcinoma (PTC) has steadily increased over the recent years, making this cancer a common malignant tumor world-wide. We tested the hypothesis that Nuclear Enriched Abundant sh-NEAT1 knock-down ranscript 1 (NEAT1) is involved in the pathogenesis of PTC in vitro and in vivo. We show that NEAT1 is highly expressed in Papillary Thyroid Carcinoma cell line (PTC-1) and anaplastic thyroid cancer cell line (SW1736) as compared with the human thyroid follicular epithelial cell line (Nthy-ori 3-1). shRNA knockdown of NEAT1 led to the inhibition of cell growth, invasion, migration and Epithelial to Mesenchymal Transition (EMT) of thyroid cancer cells. This treatment increased the rate of apoptosis in SW1736 cells. Silencing of NEAT1 increased the level of its regulator, miRNA-126 and down-regulated VEGFA that sets the density of tumor vasculature. Administrtation of sh-NEAT1 also inhibited tumor growth in vivo, increased the miRNA-126 level and down-regulated VEGFA. Taken together, these results indicate that silencing NEAT1 suppresses thyroid carcinoma via miR-126/NEAT1/VEGFA axis.

EZH2 upregulation by ER\u03b1 induces proliferation and migration of papillary thyroid carcinoma

BackgroundThe incidence of papillary thyroid carcinoma (PTC) has been increasing worldwide in recent years. Therefore, novel potential therapeutic targets for PTC are urgently needed. Enhancer of zeste homolog 2 (EZH2), a methyltransferase belonging to PRC2, plays important roles in epigenetic silencing and cell cycle regulation. EZH2 overexpression has been found in several malignant tumor tissues, while its expression and function in PTC are largely unknown.MethodsSixty-five cases of PTC tissue confirmed by pathology and 30 cases of normal thyroid tissue adjacent to PTC tissue were collected from patients undergoing surgical treatment, between February 2003 and February 2006. We investigated the clinic pathologic significance of EZH2 expression using Realtime-PCR and IHC in 65 human PTC tissues and 30 normal thyroid tissue samples. The EZH2 expression in human PTC cell lines (K1 and W3) and the normal thyroid follicular epithelial cell line Nthy-ori 3–1 was analyzed by Western blotting and Realtime PCR. The expressions of ERα and ERβ in cell lines were analyzed by Realtime PCR.The tumor cell biological behavior was evaluated by CCK8 assay, colony formation assay, transwell migration assay and xenograft tumors model.ResultsHigher rate of EZH2 expression was found in PTC tissues than in normal thyroid tissues, EZH2 expression is associated with lymph node metastasis and recurrent. Inhibition of EZH2 in PTC cell lines downregulates cellular proliferation and migration. PTC is a disease with high incidence of female and E2-ERα upregulates EZH2 expression.ConclusionsThese results suggest a potential role of EZH2 for the PTC growth and metastasis. As a novel therapy, a pharmacological therapy targeting EZH2 has full potential in treatment of PTC.

PTEN-knockdown disrupts the morphology, growth pattern and function of Nthy-Ori 3-1 cells by downregulating PAX8 expression.

The incidence of thyroid disorders, which are common endocrine diseases, has rapidly increased in recent years. However, the etiology and pathogenesis of these disorders remain unclear. Phosphatase and tension homolog (PTEN) is a dual-specific phosphatase that is associated with multiple thyroid disorders; however, the role of PTEN in thyroid disorders remains unknown. In the present study, the human thyroid follicular epithelial cell line Nthy-Ori 3-1 was used to determine the role of PTEN in thyroid disorders. PTEN expression was knocked down using a PTEN-specific short hairpin RNA. Western blotting was subsequently used to determine protein expression, the Matrigel tube formation assay and iodide uptake assay were applied for evaluating the morphology and function of thyroid cells. The results showed that PTEN knockdown decreased the protein expression of paired box 8 (PAX8). The morphology and tubular-like growth pattern of thyroid cells were therefore disrupted, and restoration of PAX8 expression reversed these effects. Furthermore, PTEN-knockdown decreased the expression of specific thyroid proteins (thyroglobulin, TG; thyroid peroxidase, TPO; and sodium/iodide symporter, NIS) and inhibited the iodide uptake ability of thyroid cells by downregulating PAX8, suggesting that PTEN deficiency may impair the function of thyroid cells. In conclusion, the present study reported an important function of PTEN in normal thyroid cells and identified the involvement of PAX8. These results may improve understanding of the role of PTEN in the pathogenesis of thyroid disorders.

Evaluation of oxidative stress in patients of follicular thyroid cancer and study the therapeutic effect of Resveratrol on oxidative stress in FTC-133 thyroid cancer cell line

The second most common cancer of the Thyroid gland is FollicularThyroid Carcinoma (FTC), second only to papillary carcinoma. Resveratrol, a natural polyphenolic compound that has anti- oxidative, anti-inflammatory and apoptotic properties, appears to have substantial cardio protection and cancer-prevention properties. Furthermore, resveratrol is thought to be responsible for regulating several biological processes, such as metabolism and aging, through the modulation of the mammalian silent information regulator 1 (SIRT1) of the Sirtuins family. The purpose of this study is evaluating erythrocyte malondialdehyde’s (MDA) role in the indication of the oxidative status in follicular thyroid carcinoma patients and investigating the therapeutic effect of resveratrol, a potent antioxidant, upon oxidative stress levels in thyroid cancer in vitro.Malondialdehyde was evaluated in erythrocyte of follicular thyroid cancer patients after and before treatment with sodium stibogluconate .Cytotoxicity by MTT assay and intracellular reactive oxygen species (ROS) levels was measured after resveratrol treatment on follicular thyroid carcinoma FTC-133 cell line. The results of this study confirmed that150 μM Resveratrol inhibited proliferation of FTC-133 thyroid cancer cell line in vitro by 88% after 72hand treatment with 50-200μM Resveratrol reduced ROS levels.To sum up,considering its mode of action, resveratrol might have an important role providing a source for natural antitumor agents, a fact that would have great therapeutic potential in integrated oncology.

Long noncoding RNA ABHD11-AS1 functions as a competing endogenous RNA to regulate papillary thyroid cancer progression by miR-199a-5p/SLC1A5 axis

With the increasing incidence of papillary thyroid cancer (PTC), more attention has been paid to exploring the mechanism of PTC initiation and progression. In addition, ectopic expression of long noncoding RNAs (lncRNAs) is reported to play a pivotal role in multiple human cancers. Based on these findings, we examined lncRNA ABHD11 antisense RNA 1 (ABHD11-AS1) expression and its clinical significance, biological function and mechanism in PTC. First, we analyzed thyroid ABHD11-AS1 expression in The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. Then, qRT-PCR was applied to detect the expression in paired PTC tissues and adjacent normal tissues, as well as in PTC cell lines (TPC-1 and K-1) and a normal thyroid follicular epithelium cell line (Nthy-ori3-1). In addition, we validated the relationship between ABHD11-AS1 expression and clinicopathological features by the Pearson X2 test. The oncogenic role of ABHD11-AS1 and its regulation of miR-199a-5p in PTC were examined by biological assays. Finally, bioinformatics analysis and mechanism assays were used to elucidate the underlying mechanism. We found that ABHD11-AS1 was remarkably overexpressed in PTC, and high expression was related to tumor size, lymph node metastasis, extrathyroidal extension and advanced TNM stage. Moreover, ABHD11-AS1 enhanced the abilities of cell proliferation, migration, and invasion, inhibited apoptosis in vitro, promoted tumorigenesis in vivo via sponging miR-199a-5p and then induced SLC1A5 activation. In addition, rescue assays were performed to confirm the ABHD11-AS1/miR-199a-5p/SLC1A5 axis. Taken together, the data show that ABHD11-AS1 acts as a competing endogenous RNA (ceRNA) to exert malignant properties in PTC through the miR-199a-5p/SLC1A5 axis. Therefore, our study may shed light on PTC diagnosis and therapies.

Exosomes Expressing Thyrotropin Receptor Attenuate Autoantibody-Mediated Stimulation of Cyclic Adenosine Monophosphate Production.

Background: Exosomes or small extracellular vesicles secreted from cells are nanovesicles with a diameter of 40-150 nm, which play a number of roles in both physiologic and pathologic processes. In Graves' disease (GD), autoantibodies bind to the thyrotropin receptor (TSHR) on the surface of thyroid follicular epithelial cells and stimulate thyroid growth and thyroid hormone synthesis and secretion via cyclic adenosine monophosphate (cAMP) production. The present study aimed to confirm the existence of TSHR in exosomes secreted from thyroid cells and to define the role of TSHR exosomes in GD. Methods: Exosomes were isolated by differential centrifugation from the culture medium of the human thyroid follicular epithelial cell line (NTHY-ori 3-1) and thyroid carcinoma cell lines (8305C, 8505C, and FTC-133). TSHR expression in cell lysates and exosomes was evaluated by Western blot analysis. In order to study the function of TSHR exosomes, human embryonic kidney (HEK) 293 cells stably expressing TSHR (HEK/TSHR) were established. Using exosomes isolated from both HEK and HEK/TSHR cells, the binding capacity of the M22 human monoclonal autoantibody to TSHR exosomes and their effect on M22-mediated stimulation of cAMP production in HEK/TSHR cells were evaluated. As a positive control for the functional assay, human recombinant TSHR chimera protein capable of binding to TSH was used. Results: TSHR was detected in exosomes from cancer cells as well as normal epithelial cells. An in vitro binding assay showed that alkaline phosphatase-labeled M22 bound to TSHR exosomes in a dose-dependent manner. M22 dose-dependently stimulated intracellular cAMP production in HEK/TSHR cells. The addition of exosomes from HEK/TSHR cells but not those from parental HEK cells significantly ameliorated cAMP production stimulated by treatment with M22 in HEK/TSHR cells. A decoy effect similar to TSHR exosomes was observed for human recombinant TSHR chimera. Conclusions: The results suggest that exosomes expressing TSHR may be secreted from normal and cancerous thyroid cells. In the thyroid gland of patients with GD, TSHR exosomes may exert a decoy effect by sequestering autoantibody, thereby ameliorating autoantibody-mediated activation of thyroid function.

Knockdown of HCP5 exerts tumor-suppressive functions by up-regulating tumor suppressor miR-128-3p in anaplastic thyroid cancer

Anaplastic thyroid cancer (ATC) is a rare type of thyroid cancer with a high mortality rate. HLA complex P5 (HCP5), a long non-coding RNA (lncRNA), has been shown to be implicated in several types of cancer, such as follicular thyroid carcinoma (PTC), the main type of thyroid cancer. However, the role of HCP5 in ATC remains unclear. The present study aimed to investigate the expression of HCP5 in ATC and its potential roles. The expression levels of HCP5 and microRNA (miR)-128-3p were tested using qRT-PCR. MTT assay was performed to detect cell viability. Cell apoptosis was evaluated by detecting apoptotic rate and caspase-3/7 activity. Luciferase reporter and RNA immunoprecipitation (RIP) assays were carried out to confirm the association between HCP5 and miR-128-3p. Compared with human thyroid follicular cell line Nthy-ori 3-1 cells, HCP5 expression level was significantly increased in ATC cell lines. Besides, HCP5 expression level was increased in ATC tissues when compared with adjacent normal tissues. Knockdown of HCP5 reduced cell viability, while elevated apoptotic rate and caspase-3/7 activity in ARO and SW1736 cells. MiR-128-3p was predicted to be a target gene of HCP5. The expression level of miR-128-3p was significantly decreased in ATC cells and tissues, as compared to Nthy-ori 3-1 cells and adjacent normal tissues, respectively. MiR-128-3p overexpression reduced ATC cell viability, and induced cell apoptosis. HCP5 directly bound to miR-128-3p and regulated the expression of miR-128-3p in ARO and SW1736 cells. Furthermore, the effects of HCP5 knockdown on ATC cell viability and apoptosis were attenuated by the inhibitor of miR-128-3p. These findings suggested that knockdown of HCP5 exerted anti-tumor effect via sponging miR-128-3p in ATC, which might provide a potential approach for the treatment of ATC.

Exosomes increased angiogenesis in papillary thyroid cancer microenvironment.

Tumour-derived exosomes under hypoxic conditions contain informative miRNAs involved in the interaction of cancer and para-carcinoma cells, thus contributing to tissue remodelling of the tumour microenvironment (TME). Exosomes isolated from hypoxic papillary thyroid cancer cells, BCPAP cells and KTC-1 cells enhanced the angiogenesis of human umbilical vein endothelial cells (HUVECs) compared with exosomes isolated from normal thyroid follicular cell line (Nthy-ori-3-1), normoxic BCPAP or KTC-1 cells both in vitro and in vivo. miR-21-5p was significantly upregulated in exosomes from papillary thyroid cancer BCPAP cells under hypoxic conditions, while the exosomes isolated from hypoxic BCPAP cells with knockdown of miR-21-5p attenuated the promoting effect of angiogenesis. In addition, our experiment revealed that miR-21-5p directly targeted and suppressed TGFBI and COL4A1, thereby increasing endothelial tube formation. Furthermore, elevated levels of exosomal miR-21-5p are found in the sera of papillary thyroid cancer patients, which promote the angiogenesis of HUVECs. Taken together, our study reveals the cell interaction between hypoxic papillary thyroid cancer cells and endothelial cells, elucidating a new mechanism by which hypoxic papillary thyroid cancer cells increase angiogenesis via exosomal miR-21-5p/TGFBI and miR-21-5p/COL4A1 regulatory pathway.

Interleukin 34 (IL-34) cell-surface localization regulated by the molecular chaperone 78-kDa glucose-regulated protein facilitates the differentiation of monocytic cells

Interleukin 34 (IL-34) constitutes a cytokine that shares a common receptor, colony-stimulating factor-1 receptor (CSF-1R), with CSF-1. We recently identified a novel type of monocytic cell termed follicular dendritic cell-induced monocytic cells (FDMCs), whose differentiation depended on CSF-1R signaling through the IL-34 produced from a follicular dendritic cell line, FL-Y. Here, we report the functional mechanisms of the IL-34-mediated CSF-1R signaling underlying FDMC differentiation. CRIPSR/Cas9-mediated knockout of the Il34 gene confirmed that the ability of FL-Y cells to induce FDMCs completely depends on the IL-34 expressed by FL-Y cells. Transwell culture experiments revealed that FDMC differentiation requires a signal from a membrane-anchored form of IL-34 on the FL-Y cell surface, but not from a secreted form, in a direct interaction between FDMC precursor cells and FL-Y cells. Furthermore, flow cytometric analysis using an anti-IL-34 antibody indicated that IL-34 was also expressed on the FL-Y cell surface. Thus, we explored proteins interacting with IL-34 in FL-Y cells. Mass spectrometry analysis and pulldown assay identified that IL-34 was associated with the molecular chaperone 78-kDa glucose-regulated protein (GRP78) in the plasma membrane fraction of FL-Y cells. Consistent with this finding, GRP78-heterozygous FL-Y cells expressed a lower level of IL-34 protein on their cell surface and exhibited a reduced competency to induce FDMC differentiation compared with the original FL-Y cells. These results indicated a novel GRP78-dependent localization and specific function of IL-34 in FL-Y cells related to monocytic cell differentiation.

MYC promotes the development of papillary thyroid carcinoma by inhibiting the expression of lncRNA PAX8‑AS1:28.

As a common malignancy of the endocrine system, papillary thyroid carcinoma (PTC) seriously affects the quality of life of patients. lncRNA PAX8‑AS1:28, or lnc‑PSD4‑1:14 has been reported to be abnormally expressed in PTC. However, the function of PAX8‑AS1:28 in PTC is still unknown. Therefore, the present study aimed to investigate the functions of PAX8‑AS1:28 in PTC, and to explore the possible mechanisms of action. A total of 38 patients with PTC were included and the normal thyroid follicular epithelial cell line Nthy‑ori 3‑1 and PTC cell line IHH‑4 were also used. MYC and PAX8‑AS1:28 overexpression and siRNA silencing in the cell lines were carried out. Expression of PAX8‑AS1:28, PAX8 and MYC in tumor tissue, adjacent healthy tissue and different cell lines were detected by qRT‑PCR and western blot analysis. Cell proliferation was measured by CCK‑8 assay. Expression levels of PAX8‑AS1:28 and PAX8 were lower in PTC tumor tissue and PTC cells than those in healthy tissue and normal cells. In contrast, the expression level of MYC was higher in PTC cells than that in normal cells. PAX8‑AS1:28 silencing reduced the expression level of PAX8 and promoted tumor cell growth, while PAX8‑AS1:28 overexpression increased the expression level of PAX8 and inhibited tumor cell growth. MYC silencing increased expression levels of PAX8‑AS1:28 and PAX8 and inhibited tumor cell growth, while MYC overexpression decreased expression levels of PAX8‑AS1:28 and PAX8 and promoted tumor cell growth. MYC can promote PTC by inhibiting the expression of lncRNA PAX8‑AS1:28.

Proteomic Analysis of Zn Depletion/Repletion in the Hormone-Secreting Thyroid Follicular Cell Line FRTL-5.

Zinc deficiency predisposes to a wide spectrum of chronic diseases. The human Zn proteome was predicted to represent about 10% of the total human proteome, reflecting the broad array of metabolic functions in which this micronutrient is known to participate. In the thyroid, Zn was reported to regulate cellular homeostasis, with a yet elusive mechanism. The Fischer Rat Thyroid Cell Line FRTL-5 cell model, derived from a Fischer rat thyroid and displaying a follicular cell phenotype, was used to investigate a possible causal relationship between intracellular Zn levels and thyroid function. A proteomic approach was applied to compare proteins expressed in Zn deficiency, obtained by treating cells with the Zn-specific chelator N,N,N′,N′-tetrakis (2-pyridylmethyl) ethylene-diamine (TPEN), with Zn repleted cells. Quantitative proteomic analysis of whole cell protein extracts was performed using stable isotope dimethyl labelling coupled to nano-ultra performance liquid chromatography-mass spectrometry (UPLC-MS). TPEN treatment led to almost undetectable intracellular Zn, while decreasing thyroglobulin secretion. Subsequent addition of ZnSO4 fully reversed these phenotypes. Comparative proteomic analysis of Zn depleted/repleted cells identified 108 proteins modulated by either treatment. Biological process enrichment analysis identified functions involved in calcium release and the regulation of translation as the most strongly regulated processes in Zn depleted cells.

MiR-335-5p targeting ICAM-1 inhibits invasion and metastasis of thyroid cancer cells

miRNAs is a kind of noncoding small RNAs with negative regulation function. Some miRNAs play a crucial role in the growth of tumor cells. In this study, we analyzed the role of miR-335-5p and its target gene intercellular adhesion molecule 1 (ICAM-1) in thyroid cancer. Real-time polymerase chain reaction (PCR) results showed that the expression level of ICAM-1 in cancer tissues was higher than that in their adjacent tissues. The expression level of ICAM-1 in papillary thyroid carcinoma was also significantly higher than that in other types of tumors. However, the expression of miR-335-5p is opposite to that of ICAM-1. In human thyroid cancer cell lines TPC-1, FTC-133, TT and human thyroid follicular cell line Nthyori 3-1, the expression level of ICAM-1 in TPC-1 was significantly higher than that of other cells, while the expression level of miR-335-5p in TPC-1 was significantly lower than that of other cells. When ICAM-1 expression was downregulated and miR-335-5p expression was upregulated in TPC-1 cells, ICAM-1 expression was upregulated and miR-335-5p expression was downregulated in FTC-133 cells, we found that ICAM-1 could promote the proliferation of thyroid cancer cells, while miR-335-5p could inhibit the proliferation of thyroid cancer cells. miR-335-5p could combine with 3′UTR of ICAM-1 by bioinformatics prediction. Luciferase reporter gene analysis and Western blotting detection further confirmed that miR-335-5p could target ICAM-1 and inhibit its expression. The expression level of miR-335-5p was downregulated, while the expression level of ICAM-1 was upregulated in thyroid cancer. This study will help us better understand the pathogenesis of thyroid cancer and provide new insights into the treatment of this disease.

MiR-329 inhibits papillary thyroid cancer progression via direct targeting WNT1.

Dysregulated microRNA-329 (miR-329) serves an important role in the progression of certain types of tumor. However, the exact function and mechanisms of miR-329 in papillary thyroid cancer (PTC) remain unknown. The present study investigated the function and mechanisms of miR-329 in regulating PTC cell progression. The results revealed that the expression of miR-329 was significantly downregulated in PTC tissues and cell lines compared with adjacent normal tissues and a human immortalized follicular cell line. miR-329 mimics notably decreased PTC cell proliferation, colony formation and WNT1 expression in vitro, as well as suppressing PTC tumor growth in vivo. In addition, luciferase assays determined that miR-329 was able to directly bind with the 3′untranslated region of WNT1. Furthermore, short interfering RNA-WNT1-induced downregulation of WNT1, which demonstrated similar effects to miR-329 overexpression. WNT1 overexpression rescued the tumor suppressive effects of miR-329 in PTC cells. The present study provided new insights into the role of miR-329 in PTC progression and suggests the potential application of miR-329 as a therapy for PTC.

Long non‑coding RNA UCA1 promotes papillary thyroid cancer cell proliferation via miR‑204‑mediated BRD4 activation.

Long non‑coding RNA (lncRNA) urothelial carcinoma‑associated 1 (UCA1) has been used in tumor development and progression in many types of cancer. However, the function and mechanism underlying the action of UCA1 in papillary thyroid cancer (PTC) remains unclear. Therefore, these topics were investigated in the present study by invitro and invivo experiments. It was demonstrated that the expression level of UCA1 was more significantly upregulated in PTC cell lines and tissues when compared with the immortal human thyroid follicular cell line and adjacent normal tissues, respectively. UCA1 knockdown significantly inhibited PTC cell viability, colony formation and the bromodomain containing 4 (BRD4) expression level invitro, and retarded PTC tumor growth invivo. In the previous study, microRNA (miR)‑204 inhibited thyroid cancer progression and was regulated by UCA1 in other types of cancer. In addition, by conducting dual luciferase reporter assays, it was confirmed that miR‑204 directly binds to UCA1 and the 3'‑untranslated region of BRD4. Furthermore, UCA1 competed with BRD4 for miR‑204 binding. miR‑204 knockdown enhanced BRD4 expression, which can be partially restored by short hairpin‑UCA1. The results of the present study illustrated that UCA1 promotes PTC progression by acting as a competing endogenous RNA by sponging miR‑204. In conclusion, UCA1 may be regarded as an oncogenic lncRNA, promoting PTC cell proliferation, and be a potential target for human PTC treatment.