title: The role of the proteasome in apoptosis induced by anthracycline anticancer agents.
abstract: To elucidate the involvement of proteasome inhibition in apoptosis induced by anthracycline anticancer agents, we investigated the interaction between the proteasome and anthracycline anticancer agents, and the function of the proteasome in apoptosis. Exposure of L1210 mouse lymphocytic leukemia cells to adriamycin (ADM) or 4'-O-tetrahydropyranyladriamycin (THP) resulted in apoptosis in a dose-dependent manner: 5 microM ADM and 0.5 microM THP induced apoptosis efficiently, but the effects of 10 microM ADM and 5 microM THP were markedly decreased or completely absent. Carbobenzoxy-leucyl-leucyl-leucinal (Z-LLLal), a specific proteasome inhibitor, also induced dose-dependent apoptosis of the cells. The inhibitory effect of THP on chymotrypsin-like protease activity of proteasomes purified from the cytosol of L1210 cells was stronger than that of ADM. Both of these agents showed reversible non-competitive inhibitory effects. The intracellular content of ubiquitinated protein increased in ADM-, THP- or Z-LLLal-treated L1210 cells during apoptosis. These results suggested that anthracycline anticancer agents induce apoptosis by interacting, at least in part, with proteasomes.
authors.affiliation: Laboratory of Toxicology, Graduate School of Veterinary Medicine, Osaka Prefecture University, Sakai 599-8531, Japan. kiyomiya@vet.osakafu-u.ac.jp
authors.forename: Ken-Ichi
authors.initials: K
authors.lastname: Kiyomiya
authors.forename: Masaru
authors.initials: M
authors.lastname: Kurebe
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Nakagawa
authors.forename: Saburou
authors.initials: S
authors.lastname: Matsuo
mesh_terms: D000818:Animals; D000903:Antibiotics, Antineoplastic / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects*; D053148:Caspase 3; D020169:Caspases / Q000502:physiology; D003546:Cysteine Endopeptidases / Q000502:physiology*; D004317:Doxorubicin / Q000031:analogs & derivatives / Q000494:pharmacology; D004789:Enzyme Activation; D007939:Leukemia L1210; D007976:Leupeptins / Q000494:pharmacology; D051379:Mice; D009097:Multienzyme Complexes / Q000037:antagonists & inhibitors / Q000502:physiology*; D046988:Proteasome Endopeptidase Complex; D025801:Ubiquitin / Q000378:metabolism
chemical_list: D000903:Antibiotics, Antineoplastic; D007976:Leupeptins; D009097:Multienzyme Complexes; D025801:Ubiquitin; D004317:Doxorubicin; C027260:pirarubicin; C505409:Casp3 protein, mouse; D053148:Caspase 3; D020169:Caspases; D003546:Cysteine Endopeptidases; D046988:Proteasome Endopeptidase Complex; C072553:benzyloxycarbonylleucyl-leucyl-leucine aldehyde