Anticancer effect of inactivated Sendai virus strain Tianjin on human osteosarcoma HOS cells.

Ultraviolet-inactivated Sendai virus strain Tianjin (UV-Tianjin) has been proved to have antitumor effects in many kinds of tumor cells. Here, we investigated the anticancer properties of UV-Tianjin on human osteosarcoma HOS cells and the underlying molecular mechanism. Apoptosis, intracellular reactive oxygen species (ROS) levels and mitochondrial membrane potential were determined by flow cytometry analysis. The expression levels of apoptosis-related proteins were tested by western blotting. The results showed that UV-Tianjin concentration-dependently induced apoptosis in HOS cells. UV-Tianjin-induced apoptosis was mediated by the mitochondrial pathway, which was confirmed by mitochondrial dysfunction, downregulation of B-cell lymphoma 2 (Bcl-2), B-cell lymphoma-xL (Bcl-xL) and myeloid cell leukemia-1 (Mcl-1), upregulation of B-cell lymphoma 2 associated X protein (Bax) and Bcl-2 Homologous Antagonist/Killer (Bak), as well as the cleavage of caspase-9 and -3. Further analysis showed that UV-Tianjin augmented the phosphorylation of c-Jun N-terminal kinase, the extracellular-regulated kinase and p38, the major components of mitogen-activated protein kinase (MAPK) pathways, as well as the generation of ROS. Moreover, UV-Tianjin-induced apoptosis was remarkably attenuated by MAPK inhibitors and ROS inhibitor. Taken together, our results indicated that UV-Tianjin exerts antitumor effects by inducing mitochondria-dependent apoptosis involving ROS generation and MAPK pathway in human osteosarcoma HOS cells.