Combined effects of bortezomib and daunorubicin on multiple myeloma cell KM3 in vitro.

The aim of this study was to investigate the combined effects of bortezomib (Bor) and daunorubicin (DNR) or each drug alone on proliferation of human multiple myeloma cell line KM3. KM3 cells were cultured with different concentrations of Bor and DNR, Bor or DNR alone for different times. The cell proliferation was analyzed by MTT assay, and the concentration of 50% growth inhibition (IC(50)) was calculated. The results indicated that both of Bor and DNR inhibited KM3 cell proliferation in dose dependent manner. The IC(50) of both drugs were 0.27 micromol/L and 0.16 micromol/L respectively. The inhibiting rate of Bor plus DNR on KM3 cells was much higher than that of Bor (p < 0.05). It is concluded that the Bor has synergistic inhibitory effect with DNR on the growth of KM3 cell in vitro.