Interaction between the BAG1S isoform and HSP70 mediates the stability of anti-apoptotic proteins and the survival of osteosarcoma cells expressing oncogenic MYC.
After chemotherapy, HSP70 expression in osteosarcoma cells was found in 6.7% of samples (2/30 cases), which was significantly lower than prior to chemotherapy (83.3%, 25/30 cases, P<0.05). p-AKT and HSP70 expression levels were found to be correlated with TCNR after chemotherapy (P<0.05).
When cisplatin was added to osteosarcoma cells with Hsp70 expression inhibited, a significant increase in apoptosis was demonstrated in TUNEL, caspase-3, and mitochondrial membrane potential assays.
The result of immunohistochemistry demonstrated that the expression of Hsp70, SCUBE3 protein, and CXCL14 chemotactic factor in osteosarcoma tissues was significantly higher than that in adjacent muscle tissue (p < 0.05).
Simultaneously knocking down ezrin and overexpressing HSP70 promotes apoptosis and inhibits proliferation of osteosarcoma cells and HSP70 induces CTL, enhancing the lethal effect on tumor cells.
Moreover, it was revealed that HSP70 expression decreased the sensitivity of osteosarcoma cells to baicalein via activation of PI3K/AKT and MAPK/ERK pathways.
The anti-apoptotic property of NS-398 at high dose can be mediated in part through NF-kappaB activation, hsp70 induction and a decrease in caspase-3 activity in human osteosarcoma cells.