Role of ursolic acid in inducing apoptosis of multiple myeloma U266 cells and its mechanism

Objective To study the role of ursolic acid（UA） in inducing apoptosis of multiple myeloma U266 cells and its molecular mechanism. Methods U266 cells were treated with UA. The inhibitory effect of UA on proliferation of U266 cells was detected by cell counting kit-8 test. The morphology of Annexin-Ⅴmarked U266 cells was observed under optical microscope with Wright’s staining. The apoptosis of U266 cells was detected by flow cytometry. The expressions of FGFR3, BCL2, MYC, CCND1 and P53 were detected by RT-PCR and Western blot, respectively. Results UA inhibited the proliferation of U266 cells. Optical microscopy showed that the morphology of U266 cells was irregular with formation of small vesicular membrane, vacuolization in cytoplasm, concentration and pyknosis of nucleus chromatin. Flow cytometry displayed that the number of Annexin-Ⅴ positive cells increased, the expression levels of FGFR3, BCL2, MYC, CCND1 mRNA and protein in U266 cells decreased, and those of p53 mRNA and protein increased in a dose and time dependent manner. Conclusion UA exerts its anti-multiple myeloma effect by inhibiting the proliferation and inducing the apoptosis of U266 cells, thus providing the experimental evidence for the selection of new target therapy for multiple myeloma.