CircHIPK3 Promotes Thyroid Cancer Tumorigenesis and Invasion through the Mirna-338-3p/RAB23 Axis.

Objective：Thyroid cancer is a common type of endocrine malignancy, and its incidence has been steadily increasing in many regions of the world. Numerous studies have found that the circRNAs in various cancer types are aberrantly expressed, which could be potential biological diagnostic markers and therapeutic targets. The purpose of this study was to investigate the role of circHIPK3 in the development and progression of thyroid cancer and its mechanism. Subject and Methods：qRT-PCR was used to detect the relative expression levels of circHIPK3 in thyroid cancer cell lines (K1, CAL-62, TPC1), human thyroid normal cells (Nthy-ori 3-1), 10 pairs of thyroid cancer tissues and corresponding adjacent normal tissues. CCK-8 and Transwell assays were used to detect the proliferation and metastasis ability of cells. The targeted relationships between circHIPK3-miR-338-3p and miR-338-3p-RAB23 were predicted by bioinformatics analysis and verified by dual-luciferase reporter assays. Results and Conclusion: The downregulation of circHIPK3 significantly reduced the migration, invasion and proliferation of thyroid carcinoma. Then, we demonstrated that circHIPK3 up-regulated the expression of its target gene RAB23 by sponging miR-338-3p to promote the tumorigenesis and invasiveness of thyroid cancer. This study is the first to find that circHIPK3 plays the role of oncogenetic circRNA in thyroid cancer, which may provide new insights into how circRNA affects the progression of thyroid cancer. Our study also showed that circHIPK3 could be a novel biomarker for thyroid cancer.

miR-149-5p mitigates tumor necrosis factor-α-induced chondrocyte apoptosis by inhibiting TRADD.

Introduction: Chondrocyte apoptosis as a prominent characteristic is usually accompanied by cartilage degeneration in osteoarthritis (OA). Herein, we aimed to determine the roles of miR-149-5p in tumor necrosis factor-α (TNF-α)-induced chondrocyte apoptosis. Material and methods: Human chondrocytes were cultured with TNF-α to establish an apoptosis cell model in vitro. After transfection with miR-149-5p mimics or co-expression with TRADD in chondrocytes, cell viability, apoptosis, inflammatory cytokines, mRNA and protein expression were measured using CCK8, Annexin V-FITC double staining, ELISA assays, RT-qPCR and western blotting, respectively. Results: TNF-α-induced chondrocyte apoptosis occurred in association with the inhibition of cell proliferation, the elevation of inflammatory cytokine levels and the activation of TRADD and caspase-3/8 signaling. The post-transcriptional regulatory mechanism suggested that TRADD was a direct target of miR-149-5p, and overexpression of miR-149-5p resulted in the down-regulation of TRADD protein expression in chondrocytes. In addition, miR-149-5p mimics had the ability to attenuate TNF-α-induced inflammation and apoptosis, while transfection with TRADD vector neutralized the protective effects of miR-149-5p on TNF-α-induced chondrocyte dysfunction. Conclusions: miR-149-5p inversely regulated TNF-α-mediated chondrocyte damage by inhibiting TRADD-modulated caspases signaling. The miR-149-5p/TRADD signaling pathway might be a promising therapeutic target for the treatment of OA.

Punicalin alleviates TNF-α- and IL-1ß-induced chondrocyte dysfunction and cartilage metabolism via mediating FOXO3 signaling axis.

Forkhead box O3 (FOXO3) transcription factor is involved in chondral homeostasis of normal, aging and osteoarthritis (OA) cartilage. At present, we aimed to investigate whether FOXO3 is a target of punicalin to prevent IL-1ß- and TNF-α-induced chondrocyte dysfunction in vitro and in vivo models. Cell and mouse models of chondrocyte dysfunction were established to determine the pharmacological value of hydrolyzable tannin, punicalin, which was extracted from the pomegranate. FOXO3 protein levels in the nucleus and cytoplasm were analysed using western blot. Safranine O staining was performed to evaluate the expansion of growth plate and chondrocyte differentiation in IL-1ß- and TNF-α-treated mice. In IL-1ß- and TNF-α-treated chondrocytes and mice, IL-1ß and TNF-α evoked phosphorylation and nucleocytoplasmic shuttling of FOXO3, as well as reduced FOXO3 expression levels in the nucleus. However, punicalin treatment repressed FOXO3 phosphorylation and cytoplasmic transfer. Punicalin treatment improved IL-1ß and TNF-α-induced growth inhibition and apoptosis of chondrocyte and the abnormal expansion of growth plate and hypertrophic zone. Moreover, punicalin could maintain the normal phenotype of chondrocyte via mediating multiple gene expression. Punicalin showed a beneficial effect on IL-1ß- and TNF-α-stimulated chondrocytes and cartilaginous metabolic disorders via preserving the transcriptional activity of FOXO3. PRACTICAL APPLICATIONS: Our study presents a prospective adjuvant therapeutic drug, punicalin, to prevent inflammation-related cartilage injury and chondrocyte dysfunction.

GDC-0152 attenuates the malignant progression of osteosarcoma promoted by ANGPTL2 via PI3K/AKT but not p38MAPK signaling pathway.

Angiopoietin-like protein 2 (ANGPTL2) plays an important role in inflammatory carcinogenesis and tumor metastasis. The compound GDC-0152 is a peptidomimetic small molecule antagonist of inhibitor of apoptosis (IAP) proteins with antitumor activity. However, the interaction between ANGPTL2 and GDC-0152 has not been studied. It has been proven that ANGPTL2 promotes metastasis of osteosarcoma. Therefore, in the present study, the effect of GDC-0152 on the malignant progression of osteosarcoma promoted by ANGPTL2 was investigated. Human osteosarcoma cell line SaOS2 cells were pre-treated or non-treated with GDC-0152 and then exposed to recombinant human ANGPTL2. The viability of SaOS2 cells was determined by MTT assay, the migration of SaOS2 cells was analyzed by chamber migration assay kit, and the SaOS2 cell apoptosis was determined by fluorescence-activated cell sorting (FACS) and nuclear staining. Treatment with ANGPTL2 increased SaOS2 cell growth and migration and decreased cell apoptosis. The increased cell growth and decreased cell apoptosis were significantly attenuated in SaOS2 cells receiving GDC-0152. However, the ANGPTL2-increased SaOS2 cell migration was not inhibited by GDC-0152 treatment. Furthermore, western blot analysis showed that the activation of phosphatidyl inositol 3-kinase (PI3K) (p85), PI3K (p110), protein kinase B (Akt) (Ser473), Akt (Thr308) and p38 mitogen-activated protein kinase (p38MAPK) were upregulated by ANGPTL2. Quantitative real-time polymerase chain reaction (qTR-PCR) and gelatin zymography showed that the mRNA expression and activity of matrix metalloproteinase-9 (MMP-9) and matrix metalloproteinase-2 (MMP-2) were also increased by ANGPTL2. The upregulated activation of PI3K and Akt were significantly suppressed by the treatment of GDC-0152. In contrast, GDC-0152 did not suppress ANGPTL2-induced p38MAPK phosphorylation, MMP-9/MMP-2 mRNA expression or MMP-9/MMP-2 activity. Taken together, these data indicate that GDC-0152 attenuates the malignant progression of osteosarcoma promoted by ANGPTL2 via PI3K/AKT but not p38MAPK signaling pathway. The present study indicated a novel therapeutic strategy to inhibit tumor growth by indirectly preventing ANGPTL2 signaling.