ABSTRACT
Objective To observe the anti-tumor effect on human multiple myeloma cell lines U266 and KM3 with a combination of varinostat and melphalan in vitro.Methods The cell proliferation of U266 and KM3 was datected with MTT assay when treated them with vorinostat alone and melphalan alone,then calculate their IC50 values respectively.Fixed the concentrations of vorinostator melphalan,the cell proliferation was datected in combination with melphalan/vorinostat in seriesly concentrations by MTr assay.Then to calculate drug combination index(CI).Results The IC50 value of U266 was 5.0-7.5 μmol/L and that of KM3 was 2.5-5.0 μmol/L when treated by vorinostat alone,the IC50 value of U266 was 40-60 μmol/L and that of KM3 was 60-80 μmol/L treated by melphalan alone.When fixed the concentration of vorinostat(in U266 the concentration was 1.25 μmol/L,in KM3 the concentration was 1.0 μ mol/L),Synergism(CI＜0.9)was observed when the concentrations of melphalan were 20 μmol/L,40 μmol/L,60 μ mol/L and 80 μ mol/L in U266,40 μmol/L,60 μmol/L,80 μmol/L and 100 μmol/L in KM3;When fixed the concertration of melphalan (in U266,was 10 μmol/L,in KM3 was 20 μmol/L),synergism(CI＜0.9)was observed when the concentrations of vorinostat were 1.0 μmol/L,2.5 μmol/L,5.0 μmol/L and 7.5 μmol/L in U266,and 1.0 μmol/L,2.5μmol/L,5.0 μmol/L in KM3.An additive effect was observed with the czombination of vorinostat 7.5 μmol/L plus melphalan 20 μmol/L in KM3(CI=0.93).Conclusion Vorinostat had potential anti-myeloma effect alone,and had synergistic anti-tumor effect with melphalan in vitro.