MPA increases idarubicin-induced apoptosis in chronic lymphatic leukaemia cells via caspase-3.
The caspase family of protease is speculated to have a crucial role in apoptosis. The effect of treatment with Idarubicin (IDA) and Medroxyprogesterone acetate (MPA), used alone or in combination, on the activation of Caspase-3 in canine Chronic Lymphatic Leukaemia (CLL) cells was investigated, in order to clarify the mechanism of chemo- and hormone-therapy mediated apoptosis. Caspase activity was determined by a quantitative fluorimetric assay. Apoptosis was monitored by propidium iodide (PI) and nucleosomes assay. Treatment of CLL cells for 24 h with MPA 5 microM did not significantly activate caspase-3 but its activity was increased almost 5-fold more with IDA 1 microM (P < 0.05) than control. Treatment of CLL cells with IDA 1 microM in equimolecular association with MPA was able to increase the activation of caspase-3 induced by IDA of the 61.2% (P < 0.05) in comparison with IDA alone. The activation of caspase-3 was confirmed evaluating apoptosis by PI and nucleosomes assay. Furthermore, both caspase-3 activation and apoptosis triggered by IDA alone or in combination with MPA were significantly inhibited by specific caspase-3 inhibitor AC-DEVD-CMK. These findings provide an explanation for IDA and MPA induced-apoptosis mechanism.
Florio
Salvatore
S
Department of Structures, Functions and Biological Technologies, School of Veterinary Medicine, University of Naples Federico II, Naples, Italy.
Crispino
Luca
L
Ciarcia
Roberto
R
Vacca
Giovanni
G
Pagnini
Ugo
U
de Matteis
Andrea
A
Pacilio
Carmen
C
D'Andrilli
Giuseppina
G
Kumar
Christine
C
Giordano
Antonio
A
D000590:Amino Acid Chloromethyl Ketones / Q000494:pharmacology; D000818:Animals; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects* / Q000502:physiology; D061945:Caspase Inhibitors; D020169:Caspases / Q000378:metabolism*; D004285:Dogs; D004357:Drug Synergism; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005470:Fluorometry / Q000379:methods; D015255:Idarubicin / Q000008:administration & dosage / Q000494:pharmacology*; D007527:Isoenzymes / Q000037:antagonists & inhibitors / Q000378:metabolism; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000188:drug therapy* / Q000201:enzymology / Q000473:pathology; D017258:Medroxyprogesterone Acetate / Q000008:administration & dosage / Q000494:pharmacology*; D009707:Nucleosomes / Q000187:drug effects / Q000378:metabolism; D011419:Propidium / Q000032:analysis; D014407:Tumor Cells, Cultured
D000590:Amino Acid Chloromethyl Ketones; D061945:Caspase Inhibitors; D004791:Enzyme Inhibitors; D007527:Isoenzymes; D009707:Nucleosomes; C096713:benzyloxycarbonylvalyl-alanyl-aspartyl fluoromethyl ketone; D011419:Propidium; D017258:Medroxyprogesterone Acetate; D020169:Caspases; D015255:Idarubicin