Up-regulation of cyclin B1 and cdc2 expression during 9-nitrocamptothecin-induced regression of DU145 prostate tumor.
BACKGROUND
We investigated changes in the content and subcellular localization of the cell cycle regulators, cyclin B1 and cyclin-dependent kinase cdc2, in human prostate DU145 tumor and cultured cells treated with the anticancer drug 9-nitrocamptothecin (9NC).


METHODS
Proteins of interest were identified by Western blot methodology using specific antibodies.


RESULTS
The cyclin B1 and cdc2 contents were dramatically elevated in biopsies of DU145 tumor regressing upon 9NC-treatment. In vitro, 9NC-induced apoptosis of DU145 cells was associated with up-regulation of expression and nuclear accumulation of cyclin B1 and cdc2. No changes were observed in cyclins A and E and the cyclin-dependent kinase cdk2 in 9NC-treated DU145 tumor and cultured cells.


CONCLUSIONS
9NC-induced apoptosis in DU145 cells in vivo and in vitro is associated with up-regulation of expression and nuclear localization of cyclin B1 and cdc2.
Chatterjee
D
D
Department of Molecular Biology, Cell Biology and Biochemistry, Division of Biology and Medicine, Brown University, Providence, RI 02912, USA.
Wyche
J H
JH
Pantazis
P
P
D000970:Antineoplastic Agents / Q000627:therapeutic use*; D017209:Apoptosis; D016203:CDC2 Protein Kinase / Q000378:metabolism*; D042846:CDC2-CDC28 Kinases; D002166:Camptothecin / Q000031:analogs & derivatives / Q000627:therapeutic use*; D019925:Cyclin A / Q000378:metabolism; D019926:Cyclin B / Q000378:metabolism*; D056744:Cyclin B1; D019927:Cyclin E / Q000378:metabolism; D051357:Cyclin-Dependent Kinase 2; D018844:Cyclin-Dependent Kinases / Q000378:metabolism; D006801:Humans; D009363:Neoplasm Proteins / Q000378:metabolism*; D009687:Nuclear Proteins / Q000378:metabolism; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D012074:Remission Induction; D016196:S Phase / Q000187:drug effects / Q000502:physiology; D014407:Tumor Cells, Cultured / Q000187:drug effects; D015854:Up-Regulation
D000970:Antineoplastic Agents; C534699:CCNB1 protein, human; D019925:Cyclin A; D019926:Cyclin B; D056744:Cyclin B1; D019927:Cyclin E; D009363:Neoplasm Proteins; D009687:Nuclear Proteins; D017346:Protein Serine-Threonine Kinases; D016203:CDC2 Protein Kinase; D042846:CDC2-CDC28 Kinases; C495894:CDK2 protein, human; D051357:Cyclin-Dependent Kinase 2; D018844:Cyclin-Dependent Kinases; C079905:rubitecan; D002166:Camptothecin