Project description:SaOS2 osteosarcoma cells were cultured with or without atorvastatin (10 µM) for 6, 15 or 24h (2 biological replcates). RNA were isolated and hybridized to RNG microarrays. Background Osteosarcoma is the most common primary tumor of bone. The rapid development of metastatic lesions and resistance to chemotherapy remain major mechanisms responsible for the failure of treatments and poor survival rate for patients. Methods We previously showed that the HMGCoA reductase inhibitors statins exhibit anti-tumoral effects on osteosarcoma cells. Here, using microarray analysis, we identify cyr61/CCN1 as a new target of statins. Modulations of expression of cyr61 were performed in human and murine osteosarcoma cell lines to investigate in vitro cell viability, migratory potential and invasiveness. Cyr61 expression was evaluated in 231 tissue cores from osteosarcoma patients using tissue microarray. Tumor behavior and metastases occurence were analysed by IM injection of modified osteosarcoma cells to BALB/c mice. Results Transcriptome comparisons revealed that statins down-regulate cyr61 expression in SaOS2 cells. Cyr61 silencing in human and murine osteosarcoma cell lines enhanced cell death, but reduced cell migration and cell invasion compared to parental cells whereas cyr61 overexpression had opposite effects. Tissue microarray analysis demonstrated that cyr61 protein expression is higher in human osteosarcoma compared to normal bone tissue and is further increased in metastatic tissues. In vivo, cyr61 overexpression in osteosarcoma cells enhanced lung metastases development whereas cyr61 silencing strongly reduced metastases in mice. Conclusion The results reveal that cyr61 expression increases with tumor grade in human osteosarcoma and demonstrate that cyr61 silencing inhibits in vitro osteosarcoma cell invasion and migration as well as in vivo lung metastases in mice. These data provide a novel molecular target for therapeutic intervention in metastatic osteosarcoma. Dye balance-experiment comparing atorvastatin versus untreated cells at 6, 15 and 24 hours using 2 biological replicates.
Project description:SaOS2 osteosarcoma cells were cultured with or without atorvastatin (10 µM) for 6, 15 or 24h (2 biological replcates). RNA were isolated and hybridized to RNG microarrays. Background Osteosarcoma is the most common primary tumor of bone. The rapid development of metastatic lesions and resistance to chemotherapy remain major mechanisms responsible for the failure of treatments and poor survival rate for patients. Methods We previously showed that the HMGCoA reductase inhibitors statins exhibit anti-tumoral effects on osteosarcoma cells. Here, using microarray analysis, we identify cyr61/CCN1 as a new target of statins. Modulations of expression of cyr61 were performed in human and murine osteosarcoma cell lines to investigate in vitro cell viability, migratory potential and invasiveness. Cyr61 expression was evaluated in 231 tissue cores from osteosarcoma patients using tissue microarray. Tumor behavior and metastases occurence were analysed by IM injection of modified osteosarcoma cells to BALB/c mice. Results Transcriptome comparisons revealed that statins down-regulate cyr61 expression in SaOS2 cells. Cyr61 silencing in human and murine osteosarcoma cell lines enhanced cell death, but reduced cell migration and cell invasion compared to parental cells whereas cyr61 overexpression had opposite effects. Tissue microarray analysis demonstrated that cyr61 protein expression is higher in human osteosarcoma compared to normal bone tissue and is further increased in metastatic tissues. In vivo, cyr61 overexpression in osteosarcoma cells enhanced lung metastases development whereas cyr61 silencing strongly reduced metastases in mice. Conclusion The results reveal that cyr61 expression increases with tumor grade in human osteosarcoma and demonstrate that cyr61 silencing inhibits in vitro osteosarcoma cell invasion and migration as well as in vivo lung metastases in mice. These data provide a novel molecular target for therapeutic intervention in metastatic osteosarcoma.
Project description:Tumor suppressor p53 regulates various role in the cell including cell cycle arrest, DNA repair and apoptosis. Current research achieved to investigate p53 target genes in human osteosarcoma cell line-SaOS2 cell. Examination of p53 binding protein by transfecting flag-tagged wild type p53 into SaOS2 cells.
Project description:Gene expression profiling of immortalized human mesenchymal stem cells with hTERT/E6/E7 transfected MSCs. hTERT may change gene expression in MSCs. Goal was to determine the gene expressions of immortalized MSCs.
Project description:Osteosarcoma is the most common bone sarcoma in children and young adults. While chemotherapy is universally delivered, benefit from chemotherapy is limited to roughly half of localized patients. Increasingly, intratumoral heterogeneity is being appreciated as a source of therapeutic resistance. In this study we developed and evaluated an in vitro model of osteosarcoma heterogeneity, characterizing phenotype (growth in varying environments, sensitivity to chemotherapy) and genotype. We present the genotypic and phenotypic characterization of an osteosarcoma cell line panel with a focus on coculture of the most phenotypically divergent cell lines, 143B and SAOS2. The extent of phenotypic heterogeneity can be altered with relatively modest environmental (pH, glutamine) or chemical perturbations. We demonstrate that in nutrient rich in vitro culture conditions 143B outcompetes SAOS2, but with selection pressure from nutrient variations or conventional chemotherapy, SAOS2 growth can be favored in spheroids. Importantly, perturbations that affect the faster growing cell line have only a modest effect on final spheroid size when the simplest heterogeneity state (a two-cell line coculture) is evaluated, and thus the only evaluated therapies to eliminate the spheroids were by switching therapies from a first strike to a second strike. This extensively characterized, widely available system can be modeled and scaled to allow for improved strategies to anticipate resistance in osteosarcoma due to phenotypic heterogeneity.