OBJECTIVETo investigate the proliferation- inhibitory and apoptosis inducing effect of ganglioside GM3 on human multiple myeloma cell line U266 cells and its possible mechanisms.

METHODSMTT assay and flow cytometry were used to observe the effects of GM3 ganglioside on proliferation and apoptosis of human myeloma cell line U266. Effects of different concentration of ganglioside GM3 on the mRNA expression level of BCL-2 and BAX were detected by Real-time PCR.

RESULTSMTT assay and Flow Cytometry showed that ganglioside GM3 could induce the apoptosis and inhibit the proliferation of multiple myeloma U266 cell line, and both the effects were enhanced with the increase of GM3 ganglioside concentration. Compared with the control group, the relative expression of BAX mRNA with the increase of GM3 concentration in experimental group was enhanced gradually(r=0.968), while the relative mRNA expression of anti-apoptotic gene BCL-2 was decreased gradually（r=-0.727).

CONCLUSIONGM3 ganglioside can induce apoptosis and inhibit the proliferation of U266 cell line in a concentration dependent manner. The mechanism may be related with up- regulation of BAX expression and down-regulation of BCL-2.