title: Induction of caspase-3-dependent apoptosis in human leukemia HL-60 cells by δ-elemene.
abstract: δ-Elemene, an antitumor component, is a chemical compound isolated from Curcuma wenyujin, a Chinese traditional herb. We examined whether δ-elemene could inhibit cell growth and cell cycle progression and induce apoptosis in human leukemia HL-60 cells. The results demonstrated that δ-elemene induces significant apoptosis of HL-60 cells, as shown by MTT assay, annexin V (AnV) binding of externalized phosphatidylserine (PS), and the mitochondrial probe JC-1 using flow cytometry. HL-60 cells treated with δ-elemene showed high percentages in the early apoptotic and late apoptoctic/necrotic stages, as well as caspase-3 activation of HL-60 cells. By monitoring the changes in cell cycle profiles, we confirmed that δ-elemene could interfere with the cell cycle in the G2/M phase and induce apoptosis in HL-60 cells in a time-dependent manner. Caspase-3 plays a direct role in proteolytic cleavage of the cellular proteins responsible for progression to apoptosis. Therefore we examined apoptosis in HL-60 cells after exposure to δ-elemene and measured caspase-3 activities with or without Z-Val-Ala-Asp-fluoromethylketone (z-VAD-fmk, a broad-spectrum caspase inhibitor) pretreatment using flow cytometric analysis. The results showed that δ-elemene could induce caspase-3 activation as detected by the decrease in δ-elemene-induced caspase-3 activities after treatment with z-VAD-fmk. In the present study, δ-elemene activated typical caspase-dependent apoptosis in HL-60 cells, as demonstrated by an inhibitory effect of z-VAD-fmk on this cell death. During δ-elemene-induced apoptosis, cytochrome c and apoptosis-inducing factor were released into the cytosol and BAX was translocated from the cytosol to mitochondria. However, these were not prevented by z-VAD-fmk. In conclusion, our study demonstrated that δ-elemene could induce G2/M cell cycle transition and trigger apoptosis through a caspase-3-dependent pathway.
authors: Center for Drug Non-Clinical Research and Evaluation of Pharmaceutical Industrial Research Institute in Guangzhou, Guangdong, China.
authors: Jun
authors: J
authors: Ying
authors: Wei
authors: W
authors: Yang
authors: Chun-Ying
authors: CY
authors: Xie
authors: Qin-Chun
authors: QC
authors: Ni
authors: Xue-Diao
authors: XD
authors: Pan
authors: Jin-Hua
authors: JH
authors: Dong
authors: Zhi-Min
authors: ZM
authors: Liu
authors: Xi-Sha
authors: XS
authors: Wang
mesh_terms: D000590:Amino Acid Chloromethyl Ketones / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects*; D053148:Caspase 3 / Q000378:metabolism / Q000502:physiology*; D002455:Cell Division / Q000187:drug effects; D045744:Cell Line, Tumor; D030024:Curcuma / Q000737:chemistry; D045304:Cytochromes c / Q000378:metabolism; D003600:Cytosol / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D016195:G2 Phase / Q000187:drug effects; D018922:HL-60 Cells / Q000201:enzymology* / Q000473:pathology*; D006801:Humans; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects / Q000502:physiology; D008928:Mitochondria / Q000378:metabolism; D012717:Sesquiterpenes / Q000037:antagonists & inhibitors / Q000302:isolation & purification / Q000494:pharmacology*; D013997:Time Factors; D051028:bcl-2-Associated X Protein / Q000378:metabolism
chemical_list: D000590:Amino Acid Chloromethyl Ketones; D012717:Sesquiterpenes; D051028:bcl-2-Associated X Protein; C096713:benzyloxycarbonylvalyl-alanyl-aspartyl fluoromethyl ketone; C038905:elemene; D045304:Cytochromes c; D053148:Caspase 3