BackgroundOsteosarcoma is the most frequent primary malignant bone tumor, notorious for its lung metastasis. Shikonin, an effective constituent extracted from Chinese medicinal herb, was demonstrated to induce necroptosis in some cancers.MethodsMTT assay was performed to detect cell survival rate in vitro. Flow cytometry was used to analyze cell cycle and cell death. Western blot was performed to determine the expression levels of RIP1, RIP3, caspase-3, caspase-6 and PARP. The tibial primary and lung metastatic osteosarcoma models were used to evaluate the anti-tumor effect of shikonin in vivo.ResultsThe cell survival rate was decreased in a dose and time dependent manner when treated with shikonin. No major change in cell cycle was observed after shikonin treatment. The cell death induced by shikonin could be mostly rescued by specific necroptosis inhibitor necrostatin-1, but not by general caspase inhibitor Z-VAD-FMK. The number of necrotic cells caused by shikonin was decreased after being pretreated with Nec-1 detected by flow cytometry in K7 cells. After 8-hour treatment of shikonin, the expression levels of RIP1 and RIP3 were increased while caspase-3, caspase-6 and PARP were not activated in K7 and U2OS cells determined by Western blot. Size of primary tumor and lung metastasis in shikonin treated group were significantly reduced. The protein levels of RIP1 and RIP3 in primary tumor tissues were increased by shikonin. The overall survival of lung metastatic models was longer compared with control group (p < 0.001).ConclusionsShikonin had prompt but profound anti-tumor effect on both primary and metastatic osteosarcoma, probably by inducing RIP1 and RIP3 dependent necroptosis. Shikonin would be a potential anti-tumor agent on the treatment of primary and metastatic osteosarcoma.

Osteosarcoma (OS) is the most common primary malignant bone tumor, notorious for its metastasis. We have recently shown that shikonin, an effective constituent extracted from Chinese medicinal herb, induces necroptosis in OS cells. Nevertheless, the effects of low-dose shikonin on the invasiveness of OS cells are unknown. Here, we showed that shikonin dose-dependently decreased OS cell invasiveness in both scratch wound healing assay and transwell cell migration assay. Moreover, the direct target of shikonin on cell invasiveness was found to be matrix metalloproteinase (MMP)-13. Further, the inhibitory effects of shikonin on cell invasiveness were completely abolished in MMP13-overexpressing OS cells. Together, these data suggest that shikonin may suppress OS invasiveness through MMP13 suppression. Thus, our data highlight a previous unappreciated role for shikonin in suppressing OS cell metastasis.

Background/Aims: Osteosarcoma (OS) is a primary malignant bone tumor in humans, and is notorious mainly for its distal metastases. We have recently shown that Shikonin, an effective constituent extracted from Chinese medicinal herb, inhibits OS cell invasion through suppression of matrix metalloproteinase 13 (MMP13). However, the underlying mechanisms remain unknown. Methods: Here, we studied the levels of tumor necrosis factor (TNF)-alpha-induced protein 8-like 2 (TIPE2) in OS cells upon Shikonin treatment. TIPE2 levels were adapted in OS cell lines through transfection with plasmids carrying transgene or short-hairpin interference RNA (shRNA), and the effects of TIPE2 adaptation on MMP13 and cell invasiveness were evaluated by RT-qPCR, Western blot, ELISA and transwell cell migration assay, respectively. TIPE2 levels in OS specimens from patients were examined and correlated with cancer metastases and patient survival. Results: We found that Shikonin dose-dependently decreased MMP13 levels, and increased TIPE2 levels in two OS cell lines, U2OS and SaOS-2. Overexpression of TIPE2 in U2OS significantly suppressed MMP13 levels and cell invasiveness. Depletion of TIPE2 in SaOS-2 cells significantly increased MMP13 levels and cell invasiveness. Moreover, TIPE2 levels in OS specimens were significantly decreased, compared to adjacent non-cancer bone tissue. Lower TIPE2 levels correlated with higher incidence of metastases and worse 5-year survival. Conclusion: TIPE2 mediates the suppressive effects of Shikonin on MMP13 in osteosarcoma cells, and TIPE2 may be a novel therapeutic target for OS.

Patient-specific instrumentation (PSI) was designed to improve the accuracy of preoperative planning and postoperative prosthesis positioning in total knee arthroplasty (TKA). However, better understanding needs to be achieved due to the subtle nature of the PSI systems. In this study, 3D printing technique based on the image data of computed tomography (CT) has been utilized for optimal controlling of the surgical parameters. Two groups of TKA cases have been randomly selected as PSI group and control group with no significant difference of age and sex ( > 0.05). The PSI group is treated with 3D printed cutting guides whereas the control group is treated with conventional instrumentation (CI). By evaluating the proximal osteotomy amount, distal osteotomy amount, valgus angle, external rotation angle, and tibial posterior slope angle of patients, it can be found that the preoperative quantitative assessment and intraoperative changes can be controlled with PSI whereas CI is relied on experience. In terms of postoperative parameters, such as hip-knee-ankle (HKA), frontal femoral component (FFC), frontal tibial component (FTC), and lateral tibial component (LTC) angles, there is a significant improvement in achieving the desired implant position ( < 0.05). Assigned from the morphology of patients' knees, the PSI represents the convergence of congruent designs with current personalized treatment tools. The PSI can achieve less extremity alignment and greater accuracy of prosthesis implantation compared against control method, which indicates potential for optimal HKA, FFC, and FTC angles.

Purpose. Osteosarcoma (Os) is the most frequent malignant tumor of the bone in the pediatric age group, and accumulating evidences show that lncRNAs play a key role in the development of Os. Thus, we investigated the role of RBM5-AS1 and its molecular mechanism. Methods. The expression of RBM5-AS1 in Os tissues and cell lines was detected by real-time polymerase chain reaction (QPCR). The effect of RBM5-AS1 on the proliferation of Os cells was detected using CCK8 assays and flow cytometry. The effect of RBM5-AS1 on the migration and invasion of Os cells was detected by transwell assays. And we performed QPCR and western blotting assays to investigate the relationship between RBM5-AS1 and RBM5. Finally, western blotting assays were performed to explore the mechanism of RBM5. Results. LncRNA RBM5-AS1 was overexpressed in the Os tissues and cell lines. And lncRNA RBM5-AS1 promoted Os cell proliferation, migration, and invasion in vitro and tumor growth in vivo. LncRNA RBM5-AS1 targets RBM5 in Os cells. Conclusion. To sum up, the results showed that lncRNA RBM5-AS1 promotes cell proliferation, migration, and invasion in Os.

ABSTRACT. The purpose of this study was to identify genes and pathways for osteoarthritis (OA) diagnosis and therapy. We downloaded the gene expression profile of OA from Gene Expression Omnibus (GEO) database including 10 early OA, 9 late OA, and 5 normal control samples. Next, we screened differentially expressed genes (DEGs) between early-and late-stage OA samples comparing with healthy control samples. Then, the Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) software was used to construct proteinprotein interaction (PPI) network, which was to predict the proteins that may interact with DEGs. The Gene Ontology (GO)-enrichment method was used to analyze the function of genes in the PPI networks. Meanwhile network module analysis was performed using Cytoscape. A total of 24 and 29 DEGs were identified for the early and late OA, respectively. TAC1 showed the highest degree in the PPI network. Functional annotation of the TAC1 network module indicated that this gene is associated with the G protein-coupled signal transduction pathway. In summary, TAC1, together with G protein-coupled receptors, appear to play a role in the biogenesis and progress of OA. Further analysis of this gene and pathway could therefore provide a potential target for the diagnosis and treatment of OA.

BackgroundThe aim of this study was to establish an osteosarcoma (OS) associated protein-protein interaction network and explore the pathogenesis of osteosarcoma.MethodsThe gene expression profile GSE9508 was downloaded from the Gene Expression Omnibus database, including five samples of non-malignant bone (the control), seven samples for non-metastatic patients (six of which were analyzed in duplicate), and 11 samples for metastatic patients (10 of which were analyzed in duplicate). Differentially expressed genes (DEGs) between osteosarcoma and control samples were identified by packages in R with the threshold of |logFC (fold change)| > 1 and false discovery rate < 0.05. Osprey software was used to construct the interaction network of DEGs, and genes at protein-protein interaction (PPI) nodes with high degrees were identified. The Database for Annotation, Visualization and Integrated Discovery and WebGestalt software were then used to perform functional annotation and pathway enrichment analyses for PPI networks, in which P < 0.05 was considered statistically significant.ResultsCompared to the control samples, the expressions of 42 and 341 genes were altered in non-metastatic OS and metastatic OS samples, respectively. A total of 15 significantly enriched functions were obtained with Gene Ontology analysis (P < 0.05). The DEGs were classified and significantly enriched in three pathways, including the tricarboxylic acid cycle, lysosome and axon guidance. Genes such as HRAS, IDH3A, ATP6ap1, ATP6V0D2, SEMA3F and SEMA3A were involved in the enriched pathways.ConclusionsThe hub genes from metastatic OS samples are not only bio-markers of OS, but also help to improve therapies for OS.

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