Induction of apoptosis in human leukemia cells by MCS-C2 via caspase-dependent Bid cleavage and cytochrome c release.
The purpose of the present study was to investigate the anti-proliferative and apoptotic effects of MCS-C2, a novel synthetic analogue of the pyrrolo[2,3-d]pyrimidine nucleoside toyocamycin and sangivamycin, in human promyelocytic leukemia (HL-60) cells. When treated with 5 microM MCS-C2, inhibited proliferation associated with apoptotic induction was found in the HL-60 cells in a concentration-dependent and time-dependent manner, plus nuclear DAPI staining revealed the typical nuclear features of apoptosis. However, MCS-C2 showed almost no antiproliferative effect and no apoptotic induction in normal lymphocyte cells used as a control when compared with those in HL-60 cancer cells. Moreover, a flow cytometric analysis of the HL-60 cells using FITC-dUTP and propidium iodide (PI) showed that the apoptotic cell population increased gradually from <1% at 0 h to 34% at 12 h after exposure to 5 microM MCS-C2. This apoptotic induction was associated with the cleavage of Bid and a release of cytochrome c from mitochondria into the cytosol, followed by the activation of caspase-3 and inactivation of poly(ADP-ribose) polymerase (PARP). However, there was no significant change in any other mitochondrial membrane proteins, such as Bcl-2 and Bax. Consequently, the current findings suggest that the mitochondrial pathway was primarily involved in the MCS-C2-induced apoptosis in the human promyelocytic leukemia HL-60 cells.
Kim
Min Kyoung
MK
Department of Medical Genetics and Institute of Biomedical Science, Hanyang University College of Medicine, Seoul 133-791, South Korea.
Cho
Youl-Hee
YH
Kim
Jung Mogg
JM
Chun
Moon Woo
MW
Lee
Seung Ki
SK
Lim
Yoongho
Y
Lee
Chul-Hoon
CH
D017209:Apoptosis / Q000187:drug effects*; D053148:Caspase 3; D020169:Caspases / Q000378:metabolism; D049109:Cell Proliferation / Q000187:drug effects*; D045304:Cytochromes c / Q000378:metabolism; D018922:HL-60 Cells; D006801:Humans; D007700:Kinetics; D008928:Mitochondria; D014127:Toyocamycin / Q000031:analogs & derivatives* / Q000494:pharmacology*
C502156:MCS-C2; D045304:Cytochromes c; C505407:CASP3 protein, human; D053148:Caspase 3; D020169:Caspases; D014127:Toyocamycin