Impaired thyroid hormone sensitivity increases the risk of papillary thyroid cancer and cervical lymph node metastasis.

BACKGROUND: The association of thyroid hormone sensitivity with papillary thyroid carcinoma (PTC) is unclear. This study investigated the relationship between the thyroid hormone sensitivity indices and the risk of PTC and the influence of thyroid hormone sensitivity on the aggressive clinicopathologic features of PTC. METHODS: This retrospective study recruited 1225 PTC patients and 369 patients with benign nodules undergoing surgery in Zhongshan Hospital in 2020. The thyroid hormone sensitivity indices were thyroid feedback quantile-based index (TFQI), TSH index (TSHI) and thyrotropin thyroxine resistance index (TT4RI). We employed logistic regression models to explore the correlation between the thyroid hormone sensitivity indices and the risk of PTC and its cervical lymph node metastasis (LNM). RESULTS: PTC patients had significantly higher levels of TSH, TFQI, TSHI and TT4RI compared to the patients with benign nodules, but thyroid hormone levels did not differ significantly between the two groups. Logistic regression analysis revealed that the higher levels of TFQI, TSHI, and TT4RI were associated with an increased risk of PTC after adjustment for multiple risk factors (TFQI: OR = 1.92, 95% CI: 1.39-2.65, P < 0.001; TSHI: OR = 2.33, 95% CI:1.67-3.26, P < 0.001; TT4RI: OR = 2.41, 95% CI:1.73-3.36, P < 0.001). In addition, patients with decreased thyroid hormone sensitivity had a higher risk of cervical LNM in multiple logistic regression analysis (TFQI: OR = 1.38, 95% CI:1.03-1.86, P = 0.03; TSHI: OR = 1.37, 95% CI:1.02-1.84, P = 0.04; TT4RI: OR = 1.41, 95% CI:1.05-1.89, P = 0.02). CONCLUSION: Impaired sensitivity to thyroid hormone was associated with an increased risk of PTC, and it is also associated with a higher risk of cervical LNM in PTC patients.

Insight of novel biomarkers for papillary thyroid carcinoma through multiomics.

Introduction: The overdiagnosing of papillary thyroid carcinoma (PTC) in China necessitates the development of an evidence-based diagnosis and prognosis strategy in line with precision medicine. A landscape of PTC in Chinese cohorts is needed to provide comprehensiveness. Methods: 6 paired PTC samples were employed for whole-exome sequencing, RNA sequencing, and data-dependent acquisition mass spectrum analysis. Weighted gene co-expression network analysis and protein-protein interactions networks were used to screen for hub genes. Moreover, we verified the hub genes' diagnostic and prognostic potential using online databases. Logistic regression was employed to construct a diagnostic model, and we evaluated its efficacy and specificity based on TCGA-THCA and GEO datasets. Results: The basic multiomics landscape of PTC among local patients were drawn. The similarities and differences were compared between the Chinese cohort and TCGA-THCA cohorts, including the identification of PNPLA5 as a driver gene in addition to BRAF mutation. Besides, we found 572 differentially expressed genes and 79 differentially expressed proteins. Through integrative analysis, we identified 17 hub genes for prognosis and diagnosis of PTC. Four of these genes, ABR, AHNAK2, GPX1, and TPO, were used to construct a diagnostic model with high accuracy, explicitly targeting PTC (AUC=0.969/0.959 in training/test sets). Discussion: Multiomics analysis of the Chinese cohort demonstrated significant distinctions compared to TCGA-THCA cohorts, highlighting the unique genetic characteristics of Chinese individuals with PTC. The novel biomarkers, holding potential for diagnosis and prognosis of PTC, were identified. Furthermore, these biomarkers provide a valuable tool for precise medicine, especially for immunotherapeutic or nanomedicine based cancer therapy.

Siglec15 promotes the migration of thyroid carcinoma cells by enhancing the EGFR protein stability.

PURPOSE: Sialic acid-bound immunoglobulin-like lectin 15 (Siglec15) has emerged as a novel therapeutic target in tumor immunotherapy. This study is designed to investigate the function and mechanism of Siglec15 in thyroid carcinoma (THCA). MATERIALS AND METHODS: The information on patients with THCA from TGCA and GEO database were used to analyze the expression of Siglec15 in THCA. THCA cells were treated with Siglec15-mFc, a recombinant fusion protein consisting of the extracellular domain of human Siglec15 and murine IgG Fc. THP-1 cells expressing human Siglec15 and its mutant were co-cultured with THCA cells to mimic the contact between Siglec15-expressing tumor-associated macrophages and THCA cells. Wound-healing assay and transwell migration assay were used to examine the migration abilities of BCPAP and C643 cells. Pull-down assay was performed to examine the interaction between Siglec15 and epidermal growth factor receptor (EGFR) on the cancer cells. Cycloheximide (CHX) assay was used to evaluate the stability of the protein. RESULTS: The expression of Siglec15 in thyroid carcinoma tissues is higher than in normal tissues. Siglec15 promotes the migration of THCA cells by binding to EGFR in a sialic acid-dependent manner and increases EGFR protein expression. Inhibition of the EGFR pathway blocks the effect of Siglec15 on the migration of THCA cells. CONCLUSIONS: Our findings reveals that Siglec15 promotes the migration of thyroid carcinoma cells by enhancing the EGFR protein stability.

A novel brick for bispecific antibody construction.

In recent years, the development of bispecific antibodies (bsAbs) has become a major trend in the biopharmaceutical industry. By simultaneously engaging two molecular targets, bsAbs have exhibited unique mechanisms of action that could lead to clinical benefits unattainable by conventional monoclonal antibodies. The type of structure used to construct a bsAb directly influences the distance, angle, degree of freedom, and affinity between the two antibody binding sites and the interaction between the two antigens or the cells where the antigens are located, which have been bound by the antibody. Consequently, the structure of the bsAb is one of the most vital factors affecting its function. Herein, we reported for the first time a novel basic module bsAb format, VFV (Variable domain-Fab-Variable domain). And then, the feasibility of the VFV format was demonstrated by constructing a series of engager-like basic module bsAbs. Next, a series of VFV bsAbs containing Fc (VFV-Ig), Fab (VFV-Fab), or Hinge (VFV-Hinge) were developed based on Hxb module, and all of them had adequate purity and activity. Finally, a T cell engager bsAb with the potential to overcome on-target off-tumor activity was constructed according to the structural characteristics of VFV, which validated that the VFV module can be used as a new brick for the construction of various bsAbs. In a word, the successful construction of this bsAb format for the first time not only enriches the arsenal of the bsAb format, but also provides inspiration for the construction of new bsAbs. Nevertheless, we are fully aware that as a proof-of-concept study, this paper has many shortcomings, and there is still a lot of work to be done to determine whether VFV can serve as a platform for drug development.

Sialylation-dependent interaction between PD-L1 and CD169 promotes monocyte adhesion to endothelial cells.

The monocyte adhesion to endothelial cells is an early step in chronic inflammation. Interferon-γ (IFN-γ) is regarded as a master regulator of inflammation development. However, the significance and mechanisms of IFN-γ in the monocyte adhesion to endothelial cells remains largely unknown. IFN-γ up-regulates PD-L1 on various types of cells. Here, we performed flow cytometry to examine the contribution of IFN-γ-induced PD-L1 expression on monocyte adhesion to endothelial cells. Up-regulation of PD-L1 by IFN-γ enhanced the adhesion of monocytes to endothelial cells. By immunoprecipitation and lectin blot, PD-L1 in endothelial cells interacted with CD169/Siglec 1 in monocytes depending on the α2,3-sialylation of PD-L1. ST3Gal family (ST3ß-galactoside α-2,3-sialyltransferase) was the major glycosyltransferase responsible for the α2,3-sialylation of membrane proteins. Down-regulation of ST3Gal4 by RNAinterference partially reduced the α2,3-sialylation of PD-L1 and the PD-L1-CD169 interaction. Finally, purified PD-L1 protein with α2,3-sialylation, but not PD-L1 protein without α2,3-sialylation, partially reduced IFN-γ-induced monocyte adhesion to endothelial cells. These findings provide evidence that the interaction between PD-L1 and CD169 promoted monocyte adhesion to endothelial cells and might elucidate a new mechanism of monocyte adhesion to endothelial cells.

Safety and effectiveness of carbon nanoparticles suspension-guided lymph node dissection during thyroidectomy in patients with thyroid papillary cancer: a prospective, multicenter, randomized, blank-controlled trial.

Objective: This study aimed to evaluate the effectiveness and safety of carbon nanoparticles-guided lymph node dissection during thyroidectomy in patients with papillary thyroid cancer(PTC). Methods: Clinical trials consisted of two subgroups: unilateral lobectomy (UL; n=283) and total thyroidectomy (TT; n=286). From each subgroup, the patients were randomly assigned to two groups: the carbon nanoparticle group and control group. Primary endpoints included parathyroid hormone (PTH) levels, number of lymph nodes (LNs) detected, number of tiny lymph nodes detected, and recognition and retention of the parathyroid glands. Secondary endpoint was recognition and protection of the recurrent laryngeal nerve. Results: A total of 569 patients with PTC were recruited. There were no statistically significant differences in demographics between the carbon nanoparticles and control groups (P > 0.05). In the UL subgroup, there were no significant differences in PTH levels between the two groups at preoperative, intraoperative, and postoperative day one, and postoperative month one (P>0.05). There was no significant difference in the serum Ca2+ levels between the two groups preoperatively and at postoperative month one (P>0.05). The number of lymph nodes dissected in the carbon nanoparticles group was significantly higher than that in the control group (P<0.0001). The detection rate of tiny lymph nodes in the carbon nanoparticles group was higher than that in the control group (P=0.0268). In the TT subgroup, there was no significant difference in PTH levels between the two groups at preoperative, intraoperative, and postoperative day one (P>0.05). However, the mean PTH level in the carbon nanoparticles group was significantly higher than that of the control group at postoperative month one (P=0.0368). There was no significant difference in the serum Ca2+ levels between the two groups preoperatively and at postoperative month one (P>0.05). There were no significant differences between the two groups in the number of dissected LNs (P>0.05) or the detection rate of tiny lymph nodes (P>0.05). No drug-related AE and complications due to the injection of carbon nanoparticles were recorded in this study. There were no significant differences between the two groups in terms of parathyroid preserved in situ and recurrent laryngeal nerve injury in the UL and TT subgroups. Conclusions: Carbon nanoparticles demonstrated efficacy and safety in thyroidectomy. The application of carbon nanoparticles could significantly facilitate the identification and clearance of LNs and the optimum preservation of parathyroid function. Clinical trial registration: https://www.chictr.org.cn/, identifier ChiCTR2300068502.

Exosomal ANXA1 derived from thyroid cancer cells is associated with malignant transformation of human thyroid follicular epithelial cells by promoting cell proliferation.

Exosomes are nano­sized extracellular vesicles that can be released from cancer cells. It has been shown that cancer cell­derived exosomes may be associated with carcinogenesis by transferring signaling proteins from malignant to neighboring non­malignant cells. In addition, annexin A1 (ANXA1) is a well­known oncogene, that can be released from extracellular vesicles by cancer cells. However, the role of exosomal ANXA1 in the cell­to­cell communication of thyroid cancer and thyroid follicular epithelial cells remains unclear. In the present study, the protein expression levels of ANXA1 in thyroid cancer cells and thyroid cancer cell­derived exosomes were analyzed using western blot analysis. In addition, Cell Counting Kit­8 and Transwell assays were used to determine cell viability and invasion, respectively. The protein expression levels of ANXA1 were increased in thyroid cancer tissues and thyroid cancer cell lines. In addition, overexpression of ANXA1 significantly increased the proliferation and invasion of the SW579 cells, while knockdown of ANXA1 expression exerted the opposite results. Furthermore, ANXA1 was transferred from the SW579 cells to the Nthy­ori3­1 cells via exosomes. Exosomal ANXA1 markedly promoted the proliferation, invasion and epithelial­to­mesenchymal transition of the Nthy­ori3­1 cells. In addition, SW579 cell­derived exosomal ANXA1 promoted tumor growth in a xenograft mouse model. Collectively, these findings indicated that SW579 cell­derived exosomal ANXA1 promoted thyroid cancer development and Nthy­ori3­1 cell malignant transformation. Therefore, these findings may aid in the development of effective treatment methods for thyroid cancer.

miR-873-5p Inhibits Cell Migration and Invasion of Papillary Thyroid Cancer via Regulation of CXCL16.

AIM: Papillary thyroid cancer (PTC) is the most common type of thyroid cancer with an increasing morbidity. MicroRNAs (miRNAs) play the pivotal roles in PTC occurrence and development. The aim of this study was to investigate the biological functions of miR-873-5p and its underlying molecular mechanisms in PTC. METHODS: Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) analysis was performed to detect miR-873-5p expressions in PTC tissues and cell lines. The target gene of miR-873-5p was predicted by TargetScan and confirmed by dual-luciferase reporter assay. Furthermore, cell proliferation, migration and invasion were assessed by CCK-8, wound healing assay and transwell assay, respectively. Additionally, the expressions of CXCL16, MMP1, MMP9 and MMP13 were measured by RT-qPCR and Western blot methods, and p65, Rel-B and their phosphorylation levels were examined by Western blot. RESULTS: We found that miR-873-5p expression was downregulated in PTC tissues and cell lines. Moreover, CXCL16 was identified as a target of miR-873-5p, and its expression was upregulated in PTC tissues and cells at both mRNA and protein levels. Functionally, overexpression of miR-873-5p inhibited PTC cell proliferation, migration and invasion, while co-transfection of CXCL16 overexpression plasmid reversed the anti-tumor behaviors induced by miR-873-5p. In addition, miR-873-5p overexpression suppressed the phosphorylation of p65 and Rel-B, and decreased the mRNA and protein expression of MMP1, MMP9 and MMP13, while overexpression of CXCL16 partially abrogated the effects of miR-873-5p. CONCLUSION: MiR-873-5p functions as a tumor suppressor in PTC by inhibiting the proliferation, migration and invasion of the PTC cells via targeting CXCL16. These findings might provide a potential novel target for the therapy of PTC.

Acetylcholine promotes the self-renewal and immune escape of CD133+ thyroid cancer cells through activation of CD133-Akt pathway.

Nerves infiltrate the tumor microenvironment and stimulate the growth of cancer cells through the secretion of neurotransmitters. However, the contributions of nerves to the self-renewal capacity of cancer stem cells (CSCs) remain largely unknown. In this study, we found that CD133+ cancer cells were responsible for the initiation of thyroid cancer. Neurons were juxtaposed with CD133+ cells in thyroid cancer tissues. Acetylcholine, one of the most abundant neurotransmitters, promoted CD133 Y828 phosphorylation, and subsequently increased the interaction between CD133 and PI3K regulatory subunit p85, resulting in the activation of the PI3K-Akt pathway. Acetylcholine increased the self-renewal ability of CD133+ thyroid cancer cells through activation of CD133-Akt pathway. Furthermore, acetylcholine promoted the expression of the immune regulator PD-L1 through the activation of the CD133-Akt pathway, resulting in the resistance of CD133+ thyroid cancer cells to CD8+ T cells. However, acetylcholine receptor antagonist 4-DAMP blocked the positive effects of acetylcholine on the self-renewal and immune escape of CD133+ thyroid cancer cells. Taken together, these data suggest that acetylcholine increases the self-renewal and immune escape abilities of CD133+ thyroid cancer cells through the activation of the CD133-Akt pathway.

Upregulation of microRNA-143-3p induces apoptosis and suppresses proliferation, invasion, and migration of papillary thyroid carcinoma cells by targeting MSI2.

As a tumor-associated biological molecule, microRNA-143-3p (miR-143-3p) is implicated in the progression of papillary thyroid carcinoma (PTC). We conducted this study to elucidate the effects of miR-143-3p mediated by Musashi RNA binding protein 2 (MSI2) on the biological activities of PTC cells. The K1 cells with the lowest miR-143-3p expression were selected for the experiments. The targeting relationship between miR-143-3p and MSI2 was verified. The biological functions of miR-143-3p and MSI2 with respect to K1 cell proliferation, cycle distribution, apoptosis, invasion, migration, and tumorigenesis were studied using gain- and loss-of-function assays both in vitro and in vivo. MSI2 was verified to be a target gene of miR-143-3p. Cells treated with upregulation of miR-143-3p or silencing of MSI2 exhibited significantly decreased the expression of Bcl-2, PCNA, MCM2, Ki67, MSI2, MMP-2, and MMP-9. This was accompanied by inhibited cell proliferation, cell invasion, and migration, as well as a significant increase in Bax expression, cell cycle arrest, and cell apoptosis. More importantly, the tumor inhibitory effects of upregulated miR-143-3p were also confirmed in the tumor xenografts in nude mice. Our results indicate that upregulation of miR-143-3p suppresses the progression of PTC by impeding cell growth, invasion, and migration via downregulation of MSI2, highlighting the potential of miR-143-3p as a target for future PTC treatment.

Emerging roles of the long non-coding RNA 01296/microRNA-143-3p/MSI2 axis in development of thyroid cancer.

Thyroid cancer (TC) is an endocrine malignancy with rising incidence. Long non-coding RNAs (lncRNAs) can serve as diagnostic and prognostic biomarkers for TC. Thus, we studied roles of LINC01296 in TC progression. Initially, the Gene Expression Omnibus (GEO) database was used to detect the differentially expressed genes in human TC samples and the potential mechanism. Expression of LINC01296 and miR-143-3p in TC tissues and cells was measured. The transfection of TC cells was conducted with si-LINC01296, si-Musashi 2 (MSI2), mimic or inhibitor of miR-143-3p to determine their effects on TC cell proliferation, migration, invasion, apoptosis and the AKT/STAT3 signaling pathway. Finally, in vivo assay was performed to verify role of miR-143-3p in tumorigenesis of TC cells in nude mice. LINC01296 was predicted to bind to miR-143-3p to modulate MSI2 expression, thus regulating the occurrence and development of TC. LINC01296 was up-regulated, while miR-143-3p was down-regulated in TC cells and tissues. LNC01296 specifically bound to miR-143-3p and MSI2 was a target of miR-143-3p. Besides, LINC01296 silencing or miR-143-3p overexpression inhibited migration, invasion, proliferation and advanced apoptosis of TC cells. Additionally, silenced LINC01296 or overexpressed miR-143-3p reduced phosphorylated STAT3/STAT3, phosphorylated AKT/AKT, B-cell lymphoma-2 (Bcl-2) and CyclinD1 levels but elevated BCL2-associated X (Bax), Cleaved Caspase3 and Caspase3 levels. Also, tumorigenesis of TC cells in nude mice was inhibited with the silencing of LINC01296. In summary, LINC01296/miR-143-3p/MSI2 axis regulated development of TC through the AKT/STAT3 signaling pathway.

IL-17A secreted from lymphatic endothelial cells promotes tumorigenesis by upregulation of PD-L1 in hepatoma stem cells.

BACKGROUND & AIMS: The microenvironment regulates hepatoma stem cell behavior. However, the contributions of lymphatic endothelial cells to the hepatoma stem cell niche remain largely unknown; we aimed to analyze this contribution and elucidate the mechanisms behind it. METHODS: Associations between lymphatic endothelial cells and CD133+ hepatoma stem cells were analyzed by immunofluorescence and adhesion assays; with the effects of their association on IL-17A expression examined using western blot, quantitative reverse transcription PCR and luciferase reporter assay. The effects of IL-17A on the self-renewal and tumorigenesis of hepatoma stem cells were examined using sphere and tumor formation assays. The role of IL-17A in immune escape by hepatoma stem cells was examined using flow cytometry. The expression of IL-17A in hepatoma tissues was examined using immunohistochemistry. RESULTS: CD133+ hepatoma stem cells preferentially interact with lymphatic endothelial cells. The interaction between the mannose receptor and high-mannose type N-glycans mediates the interaction between CD133+ hepatoma stem cells and lymphatic endothelial cells. This interaction activates cytokine IL-17A expression in lymphatic endothelial cells. IL-17A promotes the self-renewal of hepatoma stem cells. It also promotes their immune escape, partly through upregulation of PD-L1. CONCLUSION: Interactions between lymphatic endothelial cells and hepatoma stem cells promote the self-renewal and immune escape of hepatoma stem cells, by activating IL-17A signaling. Thus, inhibiting IL-17A signaling may be a promising approach for hepatoma treatment. LAY SUMMARY: The microenvironment is crucial for the self-renewal and development of hepatoma stem cells, which lead to the development of liver cancer. Lymphatic endothelial cells are an important component of this niche microenvironment, helping hepatoma stem cells to self-renew and escape immune attack, by upregulating IL-17A signaling. Thus, targeting IL-17A signaling is a potential strategy for the treatment of hepatoma.

Long non-coding RNA MIAT promotes papillary thyroid cancer progression through upregulating LASP1.

BACKGROUND: Accumulating evidences indicate that long non-coding RNAs (lncRNAs) play an important role in initiation and development of thyroid cancer. However, the underlying molecular mechanism remains elusive. METHODS: To explore potential oncogenic and tumor suppressive lncRNAs in papillary thyroid cancer (PTC), we performed RNA sequencing to discover differentially expression lncRNAs between PTC tissues and matched normal tissues. RT-qPCR was used to validate differentially expressed lncRNAs. Bioinformatic analysis was performed to predicted potential miRNA and gene which might be regulated by MIAT. Cell proliferation, invasion and cycle assay were conducted to study the function of MIAT and LASP1 in PTC. RESULTS: Through analysis of RNA sequencing, we observed that lncRNA-MIAT was overexpressed in PTC tissues. The upregulation of MIAT was further confirmed in 40 pairs of PTC tissues and normal tissues we collected. In the function assays, results suggested that MIAT silencing led to inhibition of cell proliferation, invasion and disruption of cell cycle progression in PTC cells. Mechanistically, MIAT directly bound to miR-324-3p and upregulated LASP1 expression in PTC cells. In addition, expression of MIAT was positively correlated with LASP1 mRNA expression in samples collected from patients with PTC. More importantly, transfection of recombinant LASP1 attenuated MIAT silencing induced inhibition of cell proliferation, invasion and disruption of cell cycle progression in PTC cells. CONCLUSIONS: In conclusion, the findings suggest that lncRNA-MIAT may promote PTC proliferation and invasion through physically binding miR-324-3p and upregulation of LASP1.

CD133 promotes the self-renewal capacity of thyroid cancer stem cells through activation of glutamate aspartate transporter SLC1A3 expression.

CD133+ cancer stem cells are responsible for thyroid cancer initiation. The regulatory pathways essential for sustaining the self-renewal of thyroid cancer stem cells remain largely unknown. Glutamate signaling regulates the self-renewal ability of stem cells. In the present study, we found that the level of glutamate was higher in CD133+ thyroid cancer cells than in CD133- thyroid cancer cells. The transcriptional level of glutamate aspartate transporter SLC1A3 was high in CD133+ thyroid cancer cells. Activation of NF-κB signaling by CD133 was responsible for SLC1A3 high transcription level in CD133+ thyroid cancer cells. Knock down of SLC1A3 significantly reduced the level of glutamate and inhibited the self-renewal activity and tumorigenicity of CD133+ thyroid cancer cells. Overexpression of SLC1A3 rescued the negative effect of CD133 knockdown on the self-renewal capability of CD133+ thyroid cancer cells. Taken together, CD133 promotes the self-renewal capacity of CD133+ thyroid cancer cells at least partly through activation of SLC1A3 expression.

ROS-generating oxidase NOX1 promotes the self-renewal activity of CD133+ thyroid cancer cells through activation of the Akt signaling.

Thyroid cancer results from unregulated expansion of a self-renewing tumor-initiating cell population. The regulatory pathways essential for sustaining the self-renewal of tumor-initiating cells remain largely unknown. Reactive oxygen species (ROS) play a vital role in tumor initiation and progression. In the present study, we found that the level of ROS was higher in CD133 + thyroid cancer cells than in CD133- thyroid cancer cells. The transcriptional level of ROS-generating oxidase NADPH oxidase 1 (NOX1) is high in CD133 + thyroid cancer cells. Activation of STAT3 through phosphorylation is responsible for high activation of NOX1 transcription in CD133 + thyroid cancer cells. Knock down of NOX1 obviously reduced the level of ROS and inhibited the self-renewal activity and tumorigenicity of CD133 + thyroid cancer cells. Furthermore, knock down of NOX1 reduced the activity of PI3K/Akt pathway. Overexpression of active form of Akt rescued the negative effect of NOX1 knockdown on the self-renewal capability of CD133 + thyroid cancer cells. Together, NOX1 promotes the self-renewal property of CD133 + thyroid cancer cells at least partly through activation of the Akt signaling.

Long Non-coding Antisense RNA TNRC6C-AS1 Is Activated in Papillary Thyroid Cancer and Promotes Cancer Progression by Suppressing TNRC6C Expression.

Context: Evidences have shown the important role of long non-coding antisense RNAs in regulating its cognate sense gene in cancer biology. Objective: Investigate the regulatory role of a long non-coding antisense RNA TNRC6C-AS1 on its sense partner TNRC6C, and their effects on the aggressiveness and iodine-uptake ability of papillary thyroid cancer (PTC). Design: TNRC6C-AS1 was identified as the target long non-coding RNA in PTC by using microarray analysis and computational analysis. In vitro gain/loss-of-function experiments were performed to investigate the effects of TNRC6C-AS1 and TNRC6C on proliferation, apoptosis, migration, invasion and iodine-uptake ability of TPC1 cells. Expression levels of TNRC6C-AS1 and TNRC6C of 30 cases of PTC tissues and its adjacent normal thyroid tissues were determined. Results: Downregulation of TNRC6C-AS1 or overexpression of TNRC6C inhibited proliferation, migration and invasion of TPC1 cells, while apoptosis and iodine uptake was promoted in TPC1 cells. Suppression of TNRC6C-AS1 significantly increased the expression of TNRC6C in TPC1 cells. The inhibitory effect of TNRC6C-AS1 knockdown on cell proliferation, migration and invasion was attenuated when the expression of TNRC6C was suppressed simultaneously, indicating TNRC6C is a functional target of TNRC6C-AS1. The expression of TNRC6C-AS1 was significantly higher, while the TNRC6C mRNA and protein were significantly lower in PTC tissues than normal adjacent tissues. There was a significant inverse correlation between TNRC6C-AS1 and TNRC6C mRNA in PTC tissue samples. Conclusions: TNRC6C-AS1 promotes the progression of PTC and inhibits its ability of iodine accumulation by suppressing the expression of TNRC6C. Targeting TNRC6C-AS1 - TNRC6C axis may be a new promising treatment for PTC.

Monoubiquitination of Cancer Stem Cell Marker CD133 at Lysine 848 Regulates Its Secretion and Promotes Cell Migration.

CD133, a widely known marker of cancer stem cells, was recently found in extracellular vesicles. However, the mechanisms underlying CD133 translocation to the extracellular space remain largely unknown. Here we report that CD133 is monoubiquitinated. Ubiquitination occurs primarily on complex glycosylated CD133. The lysine 848 residue at the intracellular carboxyl terminus is one of the sites for CD133 ubiquitination. The K848R mutation does not affect CD133 degradation by the lysosomal pathway but significantly reduces CD133 secretion by inhibiting the interaction between CD133 and tumor susceptibility gene 101 (Tsg101). Furthermore, knockdown of the E3 ubiquitin protein ligase Nedd4 largely impairs CD133 ubiquitination and vesicle secretion. Importantly, CD133-containing vesicles are taken up by recipient cells, consequently promoting cell migration. The K848R mutation reduces cell migration induced by CD133. Taken together, our findings show that monoubiquitination contributes to CD133 vesicle secretion and promotes recipient cell migration. These findings provide a clue to the mechanisms of CD133 secretion and cancer stem cell microenvironment interactional effects.

Galectin-3 induced by hypoxia promotes cell migration in thyroid cancer cells.

BACKGROUND: The aim of this study is to investigate the role of Galectin-3 in human thyroid cancer migration. METHODS: The expression of Galectin-3 in surgical specimens was investigated using immunohistochemistry and western blot. A papillary thyroid cancer cell line (B-cpap) and an anaplastic thyroid cancer cell line (8305c) were transfected with short-hairpin RNA against Galectin-3 (Gal-3-shRNA). Low-molecular citrus pectin (LCP) was also used to antagonize Galectin-3. The migration and invasion of the cell lines were examined. The related signaling pathways were investigated to explore the Galectin-3 mechanism of action. RESULTS: Galectin-3 was highly expressed in metastasized thyroid cancers. Knocking down and antagonizing Galectin-3 significantly suppressed the migration of thyroid cancer cells. Knocking down Galectin-3 inhibited the activity of Wnt, MAPK, Src and Rho signaling pathways. Galectin-3 was up-regulated via HIF-1α in a hypoxic environment. Galectin-3 knockdown could reduce cell motility in hypoxic environments. CONCLUSION: This study suggests that Galectin-3 could act as a modulator of thyroid cancer migration, especially in hypoxic microenvironments. This regulation function of Galectin-3 may work through multiple signaling pathways.

Stathmin decreases cholangiocarcinoma cell line sensitivity to staurosporine-triggered apoptosis via the induction of ERK and Akt signaling.

Cholangiocarcinoma is a rare, but highly fatal malignancy. However, the intrinsic mechanism involved in its tumorigenesis remains obscure. An urgent need remains for a promising target for cholangiocarcinoma biological therapies. Based on comparative proteomical technologies, we found 253 and 231 different spots in gallbladder tumor cell lines and cholangiocarcinoma cell lines, respectively, relative to non-malignant cells. Using Mass Spectrometry (MS) and database searching, we chose seven differentially expressed proteins. High Stathmin expression was found in both cholangiocarcinoma and gallbladder carcinoma cells. Stathmin expression was validated using immunohistochemistry and western blot in cholangiocarcinoma tissue samples and peritumoral tissue. It was further revealed that high Stathmin expression was associated with the repression of staurosporine-induced apoptosis in the cholangiocarcinoma cell. Moreover, we found that Stathmin promoted cancer cell proliferation and inhibited its apoptosis through protein kinase B (Akt) and extracellular signal-regulated kinase (ERK) signaling. Integrin, ß1 appears to serve as a partner of Stathmin induction of ERK and Akt signaling by inhibiting apoptosis in the cholangiocarcinoma cell. Understanding the regulation of anti-apoptosis effect by Stathmin might provide new insight into how to overcome therapeutic resistance in cholangiocarcinoma.