| Objective: To investigate the effect of Shikonin on proliferation and apoptosis of leukemic NB4 cells and the related mechanism.Methods:1.CCK-8 assay was used to examine the proliferation inhibition of Shikonin on NB4 cells.2.After treatment with Shikonin,cell cycle and apoptosis of NB4 cell were detected by flow cytometry.3.Cell morphological changes were examined by Hochest 33342 staining.4.The expression of c-Myc,PARP,Caspase 3,Cleaved PARP,Cleaved Caspase 3,ERK,p-ERK,JNK,p-JNK,p38 MAPK and p-p38 MAPK were detected by Western blot.5.Observed the effects of Shikonin on tumor growth in NB4 cell xenograft mouse model by portraying growth curve.6.The expression of c-Myc was detected by immuno-histochemistry technology.Results:1.Shikonin inhibited NB4 cell proliferation in concentration and time-dependent manner(P<0.01).2.The percentage of cells in G1 phase was increased while was decreased in G2 and S phases(P<0.01).The rate of apoptosis in the Shikonin group was obviously higher than control group(P<0.01).3.The cell stained by Hoechst 33342 appeared chromatin agglutination,karyopyknosis,and nuclear fragmentation after Shikonin treatment.4.NB4 cells treated with Shikonin exhibited higher levels of cleaved caspase-3 and poly ADP-ribose polymerase(PARP)than control cells(P<0.01).Western blot results showed that the expression of p-p38 mitogen-activated protein kinase(p-p38MAPK)and p-c-Jun N-terminal kinase(p-JNK)was increased significantly by Shikonin treatment(P<0.01),while the expression of p-ERK and c-Myc was decreased(P<0.05).5.Shikonin treatment significantly suppressed the tumor growth.The average tumor weight was significantly less in Shikonin treated mouse than in control mouse(P < 0.05).6.The immuno-histochemistry showed that the expression of c-Myc was down-regulated by Shikonin in NB4 cell tumor tissue.Conclusions: Shikoin can inhibit NB4 cells proliferation and induce apoptosis and suppress the tumor growth in xenograft mouse model. |
PDF Full Text Request