title: Tanshinone IIA inhibits leukemia THP-1 cell growth by induction of apoptosis.
abstract: Tanshinone IIA, a diterpene quinone extracted from the traditional herbal medicine, Salvia miltiorrhiza Bunge, has been reported to have anti-tumor effects on a large variety of cancer cells. The present study was undertaken to investigate the in vitro antiproliferation and apoptosis inducing effects of Tanshinone IIA on leukemia THP-1 cell lines and its mechanisms of action. MTT assay was used to detect the cell growth inhibitory rate; cell apoptotic rate and the mitochondrial membrane potential (Deltapsim) were investigated by flow cytometry (FCM), apoptotic morphology was observed by Hoechst 33258 staining and DNA fragmentation analysis. The expression of caspase-3 and different apoptosis modulators were analyzed by Western blotting. The results revealed that Tanshinone IIA inhibited the growth of THP-1 cells and caused significant apoptosis, the suppression was both in time- and dose-dependent manner. After treatment by Tanshinone IIA for 48 h, the percentage of disruption of Deltapsim gradually increased in a dose-dependent manner along with marked changes of cell apoptosis. Western blotting showed cleavage of the caspase-3 zymogen protein (32-kDa) with the appearance of its 20-kDa subunit and a dose-dependent cleavage of PARP, with the appearance of 89-kDa fragment; The expression of Bcl-2 and survivin was down-regulated remarkably while Bax expression was up-regulated concurrently after the cells were treated with Tanshinone IIA for 48 h. We therefore conclude that Tanshinone IIA has significant growth inhibition effects on THP-1 cells by induction of apoptosis, and that Tanshinone IIA-induced apoptosis on THP-1 cells is mainly related to the disruption of Deltapsim and activation of caspase-3 as well as down-regulation of anti-apoptotic protein Bcl-2, survivin and up-regulation of pro-apoptotic protein Bax. The results indicate that Tanshinone IIA may serve as a potential anti-leukemia reagent.
authors.affiliation: Department of Hematology, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou 510630, PR China.
authors.forename: Jia-Jun
authors.initials: JJ
authors.lastname: Liu
authors.forename: Yong
authors.initials: Y
authors.lastname: Zhang
authors.forename: Dong-Jun
authors.initials: DJ
authors.lastname: Lin
authors.forename: Ruo-Zhi
authors.initials: RZ
authors.lastname: Xiao
mesh_terms: D045784:Abietanes; D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects*; D053148:Caspase 3 / Q000378:metabolism; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D053938:DNA Fragmentation / Q000187:drug effects; D006801:Humans; D051034:Inhibitor of Apoptosis Proteins; D007938:Leukemia / Q000188:drug therapy* / Q000473:pathology; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D008869:Microtubule-Associated Proteins / Q000032:analysis; D010616:Phenanthrenes / Q000494:pharmacology*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000032:analysis; D000077022:Survivin
chemical_list: D045784:Abietanes; D000972:Antineoplastic Agents, Phytogenic; C107489:BIRC5 protein, human; D051034:Inhibitor of Apoptosis Proteins; D008869:Microtubule-Associated Proteins; D010616:Phenanthrenes; D019253:Proto-Oncogene Proteins c-bcl-2; D000077022:Survivin; C021751:tanshinone; D053148:Caspase 3