Gynura procumbens ethanolic extract suppresses osteosarcoma cell proliferation and metastasis in vitro.

Gynura procumbens is a traditional herb used for the treatment of inflammation, rheumatism and viral infections, although the antitumor effect and its potential mechanisms of action remain unclear. In the present study, the antitumor effect of Gynura procumbens ethanolic extract (GPE) on the osteosarcoma (OS) cell line, U2-OS, was investigated in vitro. Cell proliferation and apoptosis were measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and flow cytometry assays, respectively. Transwell invasion and wound healing assays were performed to investigate the invasion and migration of the U2-OS cells. The results showed that GPE was able to inhibit U2-OS cell proliferation and metastasis and induce cell apoptosis. Furthermore, the expression of the NF-κBp65 protein was detected by western blotting to evaluate the effects of GPE on the nuclear transfer of NF-κB. It was demonstrated that the expression of the NF-κBp65 protein was significantly decreased by GPE. This indicated that GPE was able to inhibit the nuclear transfer of NF-κB. The study shows that GPE is able to induce apoptosis and suppress proliferation and metastasis in U2-OS cells via the inhibition of the nuclear translocation of NF-κB.