Aim:To examine the in vitro antitumor activity of resveratrol against multiplemyeloma(MM)cell lines(RPMI 8226,U266,and KM3),and the mechanismsinvolved.Methods:The growth inhibition of resveratrol was determined by 3-(4,5-dimethyl-2-thiazyl)-2,5-diphenyl-2H-tetrazolium bromide(MTT)assay.Theeffect of resveratrol on the apoptosis was investigated by combined annexin V-propidium iodide staining.The effect of resveratrol on the invasion throughMatrigel matrix was detected by transwell invasion analyses.The activity ofmatrix metalloproteinase(MMP)-2 and -9 proteins were determined by gelatinzymography analysis.The expression of MMP-2,MMP-9,Bcl-2,Bcl-x_L,XIAPand Bax protein were detected using Western blotting analysis.Results:Resveratrol inhibited proliferation of MM cells in a dose-and time-dependentmanner.Incubation of MM cells with resveratrol resulted in apoptotic cell death.Resveratrol down-regulated the expression of the antiapoptotic proteins Bcl-2,Bcl-x_L and XIAP and up-regulated the expression of the proapoptotic protein Bax.Furthermore,resveratrol inhibited invasion of RPMI 8226,U266,and KM3 cellswith IC_(50)values of 64±8 μmol/L,93±11 μmol/L,and 153±11 μmol/L,respectively.Resveratrol inhibited the constitutive expression of MMP-2 and-9 proteins ofMM cells and suppressed its gelatinolytic activity.Conclusion:Resveratrol in-hibits the proliferation of MM cells by inducing apoptotic cell death.Resveratrolalso inhibits MM cell invasion.The inhibition of invasion may be associated withthe attenuation of the enzymatic activities of MMP-2 and-9. Aim: To examine the in vitro antitumor activity of resveratrol against multiple myeloma (MM) cell lines (RPMI 8226, U266, and KM3), and the mechanisms in virus. Methods: The growth inhibition of resveratrol was determined by 3- -2-thiazyl) -2,5-diphenyl-2H-tetrazolium bromide (MTT) assay. The effect of resveratrol on the apoptosis was investigated by combined annexin V-propidium iodide staining. The effect of resveratrol on the invasion through Matrigel matrix was detected by transwell invasion analyzes. The activity of matrix metalloproteinase (MMP) -2 and -9 proteins were determined by gelatinzymography analysis. The expression of MMP-2, MMP-9, Bcl-2, Bcl-x_L, XIAPand Bax protein were detected using Western blotting analysis. Results: Resveratrol inhibited proliferation of MM cells in a dose-and time-dependentmanner. Population of MM cells with resveratrol resulted in apoptotic cell death. Resveratrol down-regulated the expression of the antiapoptotic proteins Bcl-2, Bcl-x_L and XIAP and up-regulated th The expression of the proapoptotic protein Bax.Furthermore, resveratrol inhibited invasion of RPMI 8226, U266, and KM3 cells with IC 50 values ​​of 64 ± 8 μmol / L, 93 ± 11 μmol / L, and 153 ± 11 μmol / L, respectively. Resveratrol inhibited the constitutive expression of MMP-2 and-9 proteins of MM cells and suppressed its gelatinolytic activity. Conflusion: Resveratrol in-hibits the proliferation of MM cells by inducing apoptotic cell death. Resveratrolalso inhibits MM cell invasion. inhibition of invasion may be associated with the attenuation of the enzymatic activities of MMP-2 and-9.