[Multiple myeloma cell line U266 apoptosis induced by velcade]

To investigate the effect of velcade on multiple myeloma cell line U266 apoptosis and its mechanism, cell viability was estimated by trypan blue dye exclusion. Annexin-V, mitochondrial transmembrane potential (delta psi m) and reactive oxygen species (ROS) labeled by DCFHDA were examined by flow cytometry, the expression of bcl-2 mRNA was detected by semi-quantitative RT-PCR. The results showed that the velcade inhibited the growth of U266 cells and reduced cell viability accompanied by appearance of morphologic characteristics of apoptosis. Velcade at 50 nmol/L increased Annexin V positivity and fluorescence intensity of DCF because of ROS generation while it decreased the delta psi m of U266 cells. Expression of anti-apoptotic gene bcl-2 mRNA also decreased. It is concluded that velcade inhibited the growth and reduce cell viability of U266 cells. Velcade can induce U266 cells apoptosis by intrinsic cell apoptotic pathway.