The inhibitory effects of cisplatin-radiation combination treatment on malignant osteosarcoma MG-63 cells and BRCA1-p53 pathways are more efficient than single treatments

CKB affects human osteosarcoma progression by regulating the p53 pathway

This study aimed to explore the role of the creatine kinase B (CKB) gene in the development of human osteosarcoma (OS). Western blotting and qRT-PCR were performed to detect CKB expression in tissues and cells. CCK-8, colony formation, flow cytometry, Transwell, and cell scratch assays were performed to detect OS cell viability, proliferation, apoptosis, invasion, and migration. Gene set enrichment analysis (GSEA) was used to conduct signal pathway enrichment. CKB expression was higher in OS tissues and cells than that in normal tissues and cells. Silencing CKB expression reduced cell proliferation, migration, and invasion, and improved cell apoptosis in HOS cells, while overexpressing CKB increased cell proliferation, migration, and invasion, and decreased apoptosis in U2-OS cells. GSEA showed that CKB affected the p53 signaling pathway. Overexpression of CKB inhibited the protein expression of p53, p21, and Bax and promoted the expression of Bcl-2 and MDM2 in U2-OS cells. Conversely, silencing CKB promoted the protein expression of p53, p21, and Bax, and inhibited the expression of Bcl-2 and MDM2 in HOS cells. Silencing p53 could reverse the effect of the silencing CKB in HOS cells, and overexpressing p53 could reverse the effect of overexpressing CKB in U2-OS cells. Taken together, CKB affects the development of OS by regulating the activity of the p53 signaling pathway.

Effects of Rapamycin Combined with Cisplatin on Tumor Necrosis Factor TNF-α in MG-63 Cells

Rapamycin (RAPA) and cisplatin (CDDP) are used as clinical drugs in the treatment of various tumors, but there are few studies on the combination of RAPA and CDDP. Tumor necrosis factor α (TNF-α) plays an important role in tumorigenesis and development. This study is to explore the effects of RAPA combined with CDDP on the expression of TNF-α in osteosarcoma MG-63 cells. MG-63 cells were routinely cultured and divided into a control group, a RAPA group (20 μM), a CDDP group (20 μM), and a RAPA + CDDP group (20 μM + 20 μM). The four groups were treated with drugs for 24 and 48 h, respectively. Real-time polymerase chain reaction (PCR), Western blot (WB), and immunocytochemistry (ICC) were adopted to detect the expression of TNF-α gene and protein. The results of PCR showed that both the separate drug use and drug combination could significantly lower the relative expression quantity of TNF-α gene (*P < 0.5), but the combination was more effective (*P < 0.5); the expression quantity of TNF-α gene in the RAPA + CDDP group at 48 h was much lower than that at 24 h (***P < 0.001). The results of WB showed that both the separate drug use and drug combination could significantly lower the relative expression quantity of TNF-α protein, and the combination was more effective than separate drug use (*P < 0.05) and more effective at 48 h (***P < 0.001); the expression quantity of TNF-α protein in the same group at 48 h was much lower than that at 24 h (*P < 0.05). The results of ICC showed that both the separate drug use and drug combination could significantly lower the relative expression quantity of TNF-α protein, and the combination was more effective than separate drug use (**P < 0.01) and more effective at 48 h (***P < 0.001); the expression quantity of TNF-α protein in the same group at 48 h was much lower than that at 24 h (**P < 0.01). RAPA combined with CDDP can significantly reduce the expression of TNF-α in MG-63 cells, which is time dependent.