Inhibitory effect of curcumin on the expressions of MAPKs and MMPs in RPMI8226 cells during their pro-liferation / 医学研究生学报

Objective curcumin can suppress the proliferation , induce apoptosis and partial differentiation , and inhibit the migration of many kinds of tumor cells .The aim of this study was to investigate the expressions of mitogen-activated protein kinase (MAPKs) and matrix metalloproteinases (MMPs) when the proliferation of human multiple myeloma RPMI8226 cells was inhibited by curcumin in vitro, and to reveal the antitumor molecular mechanism of curcumin . Methods RPMI8226 cells were treated with various concentrations of curcumin for different periods of times .The inhibitory rate of curcumin on cell proliferation was detected by MTT assay , the cell cycle analyzed by flow cytometry , the protein levels of MAPKs measured by Western blot , and the activity of MMPs analyzed by Gelatin zymography . Results Curcumin inhibited the proliferation of RPMI 8226 cells in a time-and dose-dependent manner , and the cell cycle was arrested in the G 2/M phase ([12.72 ±0.68]%vs [4.79 ±0.15]%).The expressions of JNK and p-JNK showed a con-centration-dependent increase in the RPMI8226 cells treated with curcumin at 6.25, 12.50, and 25.00 μmol/L, respectively (P0.05).In addition, the activities of MMP-2 and MMP-9 were decreased in a dose-depend-ent manner in the supernatant of RPMI8226 cells ( P <0.01). Conclusion A certain concentration of curcumin could not only acti-vate the JNK signalling pathway of the MAPKs family and induce the apoptosis of RPMI8226 cells, but also inhibit the activity of MMPs and influence the invasion and metastasis of RPMI 8226 cells.

Inhibitory effects of curcumin on human multiple myeloma cell lines and their mechanisms / 肿瘤

Objective: This study was designed to explore the effects of curcumin on the proliferation and apoptosis of human multiple myeloma cell lines H929 and RPMI8226, and to investigate their relevant mechanisms. Methods: MTT assay was used to detect the inhibitory effect of curcumin on cell proliferation. Flow cytometry (FCM) was applied to study cell cycle distribution and apoptosis rate changes. Reverse transcription-polymerase chain reaction (RT-PCR) was used to detect the mRNA expression of survivin, Bcl-2, and Bax. Results: Curcumin inhibited the proliferation of myeloma cells H929 and RPMI8226 in a time- and concentration-dependent manner. Curcumin induced apoptosis of RPMI8226 and arrested RPMI8226 cells at G2/M phase. Curcumin significantly down-regulated mRNA expression of survivin and Bcl-2 in both H929 and RPMI8226 cells, while markedly up-regulated Bax mRNA expression. Conclusion: Curcumin inhibites the proliferation and induces the apoptosis of human multiple myeloma cells. This work supposes that the effect of curcumin on transcriptions of survivin, Bcl-2 and Bax might be one of the mechanisms underlying tumor inhibitory effects of curcumin.