Long noncoding RNA SNHG14 promotes osteosarcoma progression via miR-433-3p/FBXO22 axis.

Long noncoding RNA small nucleolus RNA host gene 14 (SNHG14) has been shown to exert oncogenic functions in seceral cancers, but its role in osteosarcoma still unclear. In this present study, we found that SNHG14 was significantly upregulated in osteosarcoma tissues and cell lines. Knockdown SNHG14 expression significantly inhibited osteosarcoma cell proliferation through inducing apoptosis. Further functional assays revealed that SNHG14 knockdown dramatically suppressed cell migration and invasion. Bioinformatics analysis and luciferase assays identified that microRNA-433-3p (miR-433-3p) was a direct target of SNHG14, and directly targeted F-box only protein 22 (FBXO22). Mechanistic analysis demonstrated that SNHG14 acted as a ceRNA in modulating osteosarcoma proliferation, migration and invasion by decoying miR-433-3p to upregulate FBXO22 expression. We also observed that knockdown of FBXO22 and SNHG14 and overexpression of miR-433-3p both dramatically suppressed osteosarcoma cell proliferation, migration and invasion, but induced cell apoptosis. Moreover, the suppresive effect of SNHG14 knockdown on osteosarcoma cell proliferation, invasion and migration was attenuated by miR-433-3p inhibitor. Our findings demonstrated that SNHG14 promoted osteosarcoma progression by acting as a ceRNA for miR-433-3p to regulate FBXO22 expression, suggesting that SNHG14 may serve as a potential therapeutic target in osteosarcoma patients.

miR-186-5p Functions as a Tumor Suppressor in Human Osteosarcoma by Targeting FOXK1.

BACKGROUND/AIMS: Aberrantly expressed miRNAs play a vital role in the development of some cancers, such as human osteosarcoma (OS). However, the detailed molecular mechanisms underlying miR-186-5p-involved osteosarcoma are unclear. METHODS: qRT-PCR and western blot analysis were employed to measure the expressions of miR-186-5p and forkhead box k1 (FOXK1). CCK-8 assay evaluated the effect of miR-186-5p and FOXK1 on cell proliferation. Transwell assay confirmed cell migration and invasion. Eventually, the dual-luciferase reporter assay validated 3'-untranslated region (3'-UTR) of FOXK1 as a direct target of miR-186-5p. RESULTS: Down-regulation of miR-186-5p was identified in OS tissues and cell lines, and negatively correlated with distant metastasis, Enneking stage and poor 5-year prognosis as well as the expression of forkhead box k1 (FOXK1) protein. Further assays demonstrated that miR-186-5p overexpression had inhibitory effects on in-vitro cell proliferation, cell cycle, and in-vivo tumor growth. miR-186-5p overexpression also inhibited the epithelial-tomesenchymal transition (EMT), migration and invasion of OS cells. Importantly, miR-186-5p directly targeted FOXK1 3'-UTR and negatively regulated its expression. Silencing of FOXK1 expression enhanced the inhibitory effects of miR-186-5p on OS cell proliferation, migration and invasion. CONCLUSION: These findings highlighted miR-186-5p as a tumor suppressor in the regulation of progression and metastatic potential of OS, and may benefit the development of therapies targeting miR-186-5p in patients with OS.

MicroRNA-615 functions as a tumor suppressor in osteosarcoma through the suppression of HK2.

At present, the regulatory mechanisms of various microRNAs (miRNAs/miRs) have been elucidated in human cancers including osteosarcoma (OS). This study mainly focused on the role of miR-615 in OS, which has not yet been reported. Ninety-two OS tissues and normal samples were used in this study. Human osteoblast hFOB1.19 cells and OS cell line HOS were utilized to detect the expression of miR-615. The expression of miR-615 and gene expression were assessed by RT-qPCR and western blot analysis. Transwell, MTT and luciferase reporter assays were used to investigate the regulatory mechanism of miR-615 in OS. The results revealed that miR-615 expression was reduced in OS tissues and cells, and was associated with poor clinical outcomes and prognosis in OS patients. In addition, overexpression of miR-615 restrained cell viability and metastasis in OS. Furthermore, hexokinase 2 (HK2) was confirmed as a direct target of miR-615. Upregulation of HK2 was detected in OS tissues. The upregulation of HK2 weakened the tumor-suppressive effect of miR-615 in OS. Moreover, miR-615 blocked epithelial-mesenchymal transition (EMT) and inactivated the PI3K/AKT pathway in OS. To conclude, miR-615 acts as a tumor suppressor in OS, thus miR-615 can be used as a target for OS treatment.

[Effects on the survival of rat's abdominal axial skin flap after the combination of VEGF gene therapy and skin flap delay].

OBJECTIVE: To investigate the effect of VEGF (vascular endothelial growth factor) gene therapy and skin flap delay on the survival of rat's abdominal axial skin flap. METHODS: In 48 Wistar rats, the model of a abdominal axial skin flap supplied by right superficial epigastric vessel was created. The rats were divided into six groups. The group was treated with subcutaneous injection of pcDNA4-VEGF165, skin flap delay or VEGF injection combined with skin flap delay. 7 days later, the survival rate of the skin flap was measured; specimens were harvested from the skin flap for histological investigation of the microvessels and for immunohistochemical staining to observe the expression of VEGF. RESULTS: Every treated group was significantly higher than blank group in the average survival rate of the skin flap and group V (gene injection when delayed) has the highest one. The average number of the microvessels in group II, III, V, VI was significantly higher than group IV and blank group. Group IV > group V, VI > group II, III > blank group in lumen diameter of the microvessels. Immunohistochemical staining documented more deposition of VEGF DNA in group II, III, V, VI than group IV and blank group. CONCLUSIONS: Both administration of pcDNA4-VEGF165 and skin flap delay can improve the survival of rat's abdominal axial skin flap, but the mechanisms of the effect were different. The combination of the two ways has stronger effect.