The Effects And Mechanisms Of Baicalin On Inducing HL-60 Cells Apoptosis And Growth Inhibition

【Objective】To investigate the effects of baicalin on proliferation inhibition and apoptosis induction in human myeloid leukemia cell line HL-60 cells and on related proteins and mRNA expressions. And to study the change of PI-3K/Akt signal pathway in baicalin-induced HL-60 cells.【Methods】HL-60 cells were exposed to baicalin at different dosages. Proliferation inhibition was detected by both MTT assay and clone formation assay. The ability of baicalin to induce apoptosis of HL-60 cells was examined by flow cytometry, Annexin- V/PI double staining analysis, TUNEL labeling method, and DNA fragmentation. The expression of c-myc,bcl-2,h-TERT,pim-2,P21 and Mcl-1 gene was detected by RT-PCR; c-myc,bcl-2,h-TERT,caspase-3,Akt,mTOR and NF-ΚB protein expressions were detected by Western-blot. Furthermore, induction of differentiation in HL-60 cells was measured by expression of CD11b,CD33 and NBT assay .【Results】Baicalin remarkably inhibited the HL-60 cells proliferation, with an IC50 value of 20μmol/L. Concomitantly, apoptosis was induced in HL-60 cells, as measured by detection of DNA fragmentation,sub-G1 apoptotic peak, TUNEL apoptosis cells,and staining with Annexin V. These showed that baicalin induced apoptosis in HL-60 cells in dose-dependent and time-dependent manners when the concentration of baicalin ranged between 10μmol/L to 40μmol/L. Moreover, RT-PCR and/or Western-Blot showed the expressions of c-myc,bcl-2,h-TERT,Akt,...