Abstract
To explore the mechanisms of suppression growth and induction apoptosis of curcumin on human multiple myeloma cell line RPMI8226, the suppressive effect of curcumin on RPMI8226 was examined by MTT assay; the induction apoptosis and cell cycle arrest of curcumin on RPMI8226 were determined by flow cytometry (FCM); the changes of survivin, Bcl-2, Bax mRNA levels were detected by RT-PCR. The results showed that curcumin obviously suppressed the proliferation of RPMI8226 in both time- and dose-dependent manners, and the IC(50) were 12.15 micromol/L, 4.9 micromol/L for 24 and 48 hours respectively. FCM indicated that the apoptosis ratio rose from 10.6% of untreated cells up to 36.9% of treated cells (p < 0.05), and curcumin arrested cell cycle of RPMI8226 at G(2)/M phase. RT-PCR showed that RPMI8226 cells expressed survivin, Bcl-2 strongly and Bax slightly; while RPMI8226 cells were treated with curcumin 10 micromol/L for 24 hours, the expressions of survivin, Bcl-2 mRNA were apparently down-regulated, and the expression of Bax mRNA was markedly up-regulated. It is concluded that curcumin can suppress the proliferation of human multiple myeloma cell line RPMI8226, and induce their apoptosis. The mechanism of antitumous effect of curcumin may be related to down-regulation of survivin, Bcl-2 mRNA and up-regulation of Bax mRNA.
