Biological function of microRNA-30c/SOX9 in pediatric osteosarcoma cell growth and metastasis.

OBJECTIVE: Osteosarcoma is one of the commonest malignant bone tumors, which frequently occurs in children all over the world. To find out methods to improve the therapeutic effect of osteosarcoma, it is necessary to detect the functioning mechanism of miR-30c to regulate the proliferation and metastasis of osteosarcoma cell. PATIENTS AND METHODS: In order to reveal the expression level of miR-30c, quantitative Real-time PCR (qRT-PCR) method was chosen. To evaluate cell viability and proliferation rates, colony formation and cell counting kit-8 (CCK8) assay were introduced. Based on cell migration and invasion assay, metastasis capacity of breast cancer cells was studied. Protein levels were measured by Western blotting assay and cell cycle distribution was identified by flow cytometry. Bioinformatics analysis and Luciferase assay were used to predict and verify the target gene. RESULTS: Compared with pericarcinomatous tissues (n=38), miR-30c in osteosarcoma tissues was significantly suppressed. Overexpressed miR-30c could weaken osteosarcoma cell's abilities of viability, proliferation, migration and invasion. Moreover, it could also encourage osteosarcoma cell apoptosis and block cell cycle at G0/G1 phase. According to bioinformatics analysis and Luciferase reporter assay, SOX9 was recognized as the target gene of miR-30c. Restoration of SOX9 could make miR-30c regain the ability of suppression on tumorigenesis of osteosarcoma cells. CONCLUSIONS: MiR-30c could play an important role in tumor suppression for pediatric osteosarcoma development and metastasis by targeting SOX9 in vitro. Thus, a creative and potential target was provided for diagnosis and treatment of osteosarcoma.

Limited open reduction is better for simple- distal tibial shaft fractures than minimally invasive plate osteosynthesis.

The aim of this study was to compare the effects and indications of minimally invasive plate osteosynthesis (MIPO) and limited open reduction (LOR) for managing distal tibial shaft fractures. A total of 79 cases of distal tibial shaft fractures were treated surgically in our trauma center. The 79 fracture cases were classified into type A, B, and C (C1) according to the Arbeitsgemeinschaft für Osteosynthesefragen (AO) classification, with 28, 32, and 19 cases, respectively. Among the 79 fracture cases, 52 were closed fractures and 27 were open fractures (GUSTILO, I-II). After adequate preparation, 48 cases were treated with LOR and 31 cases were treated with MIPO. All cases were followed up for 12 to 18 months, with an average of 16.4 months. During the follow-up period, 76 fracture cases were healed in the first stage, whereas the 3 cases that developed non-union were treated by changing the fixation device and autografting. For types A, B, and some of C simple fractures (C1), LOR accelerated the fracture healing and lowered the non-union rate. One case suffered from regional soft tissue infection, which was controlled by wound dressing and intravenous antibiotics. Another case that developed local skin necrosis underwent local flap transplant. LOR promoted bone healing and lowered the non-union rate of several simple-distal tibial shaft fractures. Thereafter, the incidence of soft tissue complication was not significantly increased. However, for complex and comminuted fractures, MIPO was the preferred method for correcting bone alignment and protecting soft tissue, leading to functional recovery.