文献类型：期刊文献

英文题名：Induction of apoptosis in K562 human leukemia cells by 2′,4′-dihydroxy-6′-methoxy-3′,5′-dimethylchalcone

作者：Ye, CL; Qian, F; Wei, DZ; Lu, YH; Liu, JW

机构：[1]E China Univ Sci & Technol, Inst Biochem, State Key Lab Bioreactor Engn, Shanghai 200237, Peoples R China

年份：2005

卷号：29

期号：8

起止页码：887

外文期刊名：LEUKEMIA RESEARCH

收录：;WOS:【SCI-EXPANDED(收录号:WOS:000230369800004)】；

语种：英文

外文关键词：Cleistocalyx operculatus; flavonoids; K562; Bcl-2/Bax; apoptosis

摘要：2 ',4 '-Dihydroxy-6 '-methoxy-3 ',5 '-dimethylchalcone (DMC), isolated from the buds of Cleistocalyx operculatus, was investigated in its cytotoxicity and anti-proliferation on K562 cell line. Our results revealed that the IC50 was equal to 14.2 +/- 0.45 mu M and the EC50 was 3.3 +/- 10.14 mu M. Staining with Hoechst 33258 showed fragmentation and condensation of chromatin in the cells treated with 8 mu M DMC for 48 h. Flow cytometric analysis was performed to determine hypodiploid cells. The results of flow cytometry assay indicated that the percentage of hypodiploid K562 cells was 76.15 +/- 3.22% after 48 h treatment with 16.0 mu M DMC. The treatment resulted in the appearance of a hypodiploid peak (A(0) region), probably due to the presence of apoptosing cells and/or apoptotic bodies with DNA content less than 2n. Western blot results illustrated that in the same dosage and incubation time, DMC could down-regulate the level of Bcl-2 protein and did not influence the expression of Bax protein. The resulting net effect could thus lead to a lower ratio of Bcl-2/Bax, which might be responsible for the DMC-induced apoptosis in K562 cells. (c) 2005 Elsevier Ltd. All rights reserved.