Inactivated Sendai virus induces apoptosis mediated by reactive oxygen species in murine melanoma cells.

OBJECTIVE

This paper aims to investigate the apoptotic effect of inactivated Sendai virus (hemagglutinating virus of Japan-enveloped, HVJ-E) on murine melanoma cells (B16F10) and the possible mechanisms involved in the putative apoptotic reactions.

METHODS

B16F10 cells were treated with HVJ-E at various multiplicities of infection (MOI), and the reactive oxygen species (ROS), cell viability, and apoptosis were measured. Next, the roles of ROS in the regulation of Bcl-2/Bax and the activation of mitogen-activated protein kinase (MAPK) pathways in HVJ-E-treated B16F10 cells were analyzed. To further evaluate the cytotoxic effect of HVJ-E-generated ROS on B16F10 cells, HVJ-E was intratumorally injected, both with and without N-acetyl-L-cysteine (NAC), into melanoma tumors on BALB/c mice. Tumor volume was then monitored for 3 weeks, and the tumor proteins were separated for immunoblot assay.

RESULTS

Treatment of B16F10 cells with HVJ-E resulted in a dose-dependent inhibition of cell-viability and an induction of apoptosis. The latter effect was associated with the generation of ROS. Inhibition of ROS generation by NAC resulted in a significant reduction of HVJ-E-induced Erk1/2, JNK, and p38 MAPK activation. Additionally, ROS inhibition caused a decrease in the Bcl-2/Bax ratio as well as promoting activation of apoptosis both in vitro and in vivo.

CONCLUSION

These results suggest that HVJ-E possesses potential anticancer activity in B16F10 cells through ROS-mediated mitochondrial dysfunction involving the MAPK pathway.