[Effects of Oridonin on Proliferation Apoptosis of Human Multiple Myeloma Cells H929 in Vitro].

OBJECTIVE:To investigate the effects of oridonin (ORI) on the proliferation and apoptosis of human multiple myeloma cell line H929 and its possible mechanism. METHODS:H929 cells were exposed to ORI 0、4、8、12、16、20、24、28、32 μmol/L for 12, 24 and 36 hours respectively. The prolifcration inhibitory effect of ORI on H929 cells was determined by MTT assay and then the working concentrations of ORI were determined. The morphological changes and apoptosis of H929 cells were observed by TUNEL (TdT-mediated dUTP Nick-End Labeling) and fluorescence microscopy. The apoptosis rate of H929 cells was detected by flow cytometry with Annexin V-FITC/PI staining. The protein expressions of pro-caspase-3, BCL-2，p-PI3K, p-Akt, BAX, Cleaved PARP and p-JNK, p-ERK and p-p38 in H929 cells were detected by Western blot. RESULTS:Compared with the control group, the proliferation of H929 cells treated with the ORI of 8-16 μmol/L was significantly inhibited and the apoptosis of H929 cells was obviously increased in dose- and time-dependent manners. As for morphological changes, the characteristics of apoptotic cells were presented in H929 cells treated with ORI for 24 hours. The protein levels of pro-caspase-3, BCL-2，p-PI3K, p-Akt were down-regulated with increasing of ORI concentration（r=0.9861, r=0.9725, r=0.9413, r=0.9373）, while the BAX, Cleaved PARP and p-JNK, p-ERK and p-p38 were up-regulated（r=0.9178, r=0.8877, r=0.882, r=0.9645, r=0.8623）. CONCLUSION:The ORI possesses anti-myeloma effects, can inhibit the proliferation and induce the apoptosis of H929 cell line in vitro. Its potential mechanism may be related with up-regulating the MAPK and down-regulating the PI3K/Akt signal pathways.