[Retracted] Potentiation of the antitumor activity of adriamycin against osteosarcoma by cannabinoid WIN­55,212­2.

[This retracts the article DOI: 10.3892/ol.2015.3525.].

Potentiation of the antitumor activity of adriamycin against osteosarcoma by cannabinoid WIN-55,212-2.

Osteosarcoma is the most frequent primary malignant bone tumor that occurs in children and adolescents. The present study aimed to identify novel therapeutic strategies for osteosarcoma, by assessing the antitumor activity of the cannabinoid WIN-55,212-2 and its combined effect with adriamycin (ADM) against the MG-63 human osteosarcoma cell line. To evaluate the antiproliferative action of these molecules, a Cell Counting kit-8 (CCK-8) assay was used. The ability of cannabinoid to inhibit the migration, invasion and angiogenic activity of MG-63 cells were assessed by scratch, Transwell® chamber and angiogenesis assays, respectively, in vitro. To examine the alterations in expression of targeted genes, quantitative polymerase chain reaction and western blot analysis were used. The administration of cannabinoid combined with ADM was demonstrated to inhibit the growth of MG-63 cells, resulting in a cell viability of 32.12±3.13%, which was significantly lower (P<0.05) compared with the cell viability following treatment with cannabinoid (70.86±7.55%) and ADM (62.87±5.98%) alone. Greater antimetastasis and antiangiogenic activities were also observed following the coadministration of the two agents compared with individual treatments and controls. In addition, the expression levels of Notch-1, matrix metalloproteinase-2 (MMP-2) and vascular endothelial growth factor (VEGF) in MG-63 cells were downregulated following the treatments with cannabinoid alone or in combination with ADM. In conclusion, the present findings demonstrated that cannabinoid WIN-55,212-2 may significantly potentiate the antiproliferative, antimetastasis and antiangiogenic effects of ADM against MG-63 cells via the downregulation of Notch-1, MMP-2 and VEGF. These findings may offer a novel strategy for the treatment of osteosarcoma.

Microarray and ChIP-seq data analysis revealed changes in p53-mediated transcriptional regulation in Nutlin-3-treated U2OS cells.

Integrative analysis of chromatin immunoprecipitation-sequencing (ChIP-seq) data and microarray data was performed to illustrate the effect of Nutlin­3 on promoter selectivity and transcriptional regulation by the tumor suppressor p53 in U2OS human osteosarcoma cells. Raw data (accession number, GSE46642) were downloaded from Gene Expression Omnibus. Differential analyses were performed using package limma of R software. Gene ontology enrichment and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses were performed for the differentially expressed genes (DEGs) using the Database for Annotation, Visualization and Integration Discovery. Integrative analysis of ChIP­seq data and microarray data were confirmed with ChIP­Array. A total of 565 DEGs were identified, including 373 upregulated genes and 192 downregulated genes. Genes involved in the p53 signaling pathway, cell cycle, DNA replication, cytokine­cytokine receptor interaction and melanoma were markedly over­represented in the DEGs. A total of 39 DEGs were directly regulated by p53 and two were the transcription factors (TFs), E2F2 and HOXA1. E2F2 regulated 25 DEGs, while HOXA1 regulated one DEG. The cell cycle, p53 signaling pathway, melanoma and pathways involved in cancer were enriched in the direct and indirect target genes. Changes in the p53­binding pattern induced by Nutlin­3 were described in the present study, which may advance the understanding of the regulatory network of p53 in osteosarcoma and aid in the development of novel therapies.

Identification and functional analysis of differentially expressed genes related to metastatic osteosarcoma.

BACKGROUND: To explore the molecular mechanisms of metastatic osteosarcoma (OS) by using the microarray expression profiles of metastatic and non-metastatic OS samples. MATERIALS AND METHODS: The gene expression profile GSE37552 was downloaded from Gene Expression Omnibus database, including 2 human metastatic OS cell line models and 2 two non-metastatic OS cell line models. The differentially expressed genes (DEGs) were identified by Multtest package in R language. In addition, functional enrichment analysis of the DEGs was performed by WebGestalt, and the protein-protein interaction (PPI) networks were constructed by Hitpredict, then the signal pathways of the genes involved in the networks were performed by Kyoto Encyclopaedia of Genes and Genomes (KEGG) automatic annotation server (KAAS). RESULTS: A total of 237 genes were classified as DEGs in metastatic OS. The most significant up- and down-regulated genes were A2M (alpha-2-macroglobulin) and BCAN (brevican). The DEGs were significantly related to the response to hormone stimulus, and the PPI network of A2M contained IL1B (interleukin), LRP1 (low-density lipoprotein receptor-related protein 1) and PDGF (platelet-derived growth factor). Furthermore, the MAPK signaling pathway and focal adhesion were significantly enriched. CONCLUSIONS: A2M and its interactive proteins, such as IL1B, LRP1 and PDGF may be candidate target molecules to monitor, diagnose and treat metastatic OS. The response to hormone stimulus, MAPK signaling pathway and focal adhesion may play important roles in metastatic OS.