We found that SC repressed cell viability and migration and induced apoptosis in vitro, while combined SC and erlotinib treatment enhanced osteosarcoma growth suppression by preventing feedback activation of STAT3.
The inhibition of STAT3 in Saos-2 cells by siRNA or AG490 decreased cell proliferation, migration and invasion, down-regulated the mRNA expression of Cyclin D, Bcl-xL and Survivin and enhanced the apoptotic response.
Our findings provide information about the underlying mechanisms of miR-204/14-3-3ζ in OS cell proliferation through the STAT3 pathway, and suggest miR-204 and 14-3-3ζ as potential therapeutic targets in OS.
miR-340-5p gene expression in OS tissues and U2OS cells was significantly lower than that in paracancerous tissues and hFOB1.19 cells. miR-340-5p directly interacted with the 3'-untranslated region (3'-UTR) of STAT3 gene and negatively regulated its expression.
In summary, the present studies revealed that the loss of CtBP2 constrained distant metastasis through the JAK1/Stat3 pathway in OS, suggesting that targeting CtBP2 may be a practical anti-tumor approach to prevent OS tumor progression.
In addition, we detected the expression of vascular endothelial growth factor (VEGF) and signal transducer and activator of transcription 3 (STAT3) in osteosarcoma cell treated with Eag1 small interfering RNAs (siRNAs).
In addition, knockdown of LIF notably suppressed the proliferation and invasion of osteosarcoma via blocking the STAT3 signal pathway; in contrast, treatment with the recombinant LIF protein significantly promoted the growth and invasion of osteosarcoma through enhancing the phosphorylation of STAT3, which can be partially neutralized by the STAT3 inhibitor, HO-3867.