Record Display for the EPA National Library Catalog


Main Title Efficient Multiple-Exposure Analysis of the Toxicity of Crisnatol: A DNA Intercalator in Phase 2 Clinical Trials.
Author Zucker, R. M. ; Adams, D. J. ; Bair, K. W. ; Elstein, K. H. ;
CORP Author NSI Technology Services Corp., Research Triangle Park, NC. ;Wellcome Research Labs., Research Triangle Park, NC. ;ManTech Environmental Technology, Inc., Research Triangle Park, NC.;Health Effects Research Lab., Research Triangle Park, NC.
Publisher c1992
Year Published 1992
Report Number EPA/600/J-92/248;
Stock Number PB92-206283
Additional Subjects DNA insertion elements ; Toxicity ; Drug therapy ; Antineoplastic agents ; Drug evaluation ; Clinical trials ; Cell cycle ; Drug administration schedule ; Flow cytometry ; Cultured tumor cells ; Acute erythroblastic leukemia ; Reprints ; Crisnatol
Library Call Number Additional Info Location Last
NTIS  PB92-206283 Some EPA libraries have a fiche copy filed under the call number shown. 07/26/2022
Collation 17p
To investigate the toxicity and mechanism of action of crisnatol (CRS), a new DNA intercalator currently in phase II clinical trials, the authors analyzed cellular and nuclear flow cytometric (FCM) parameters of murine erythroleukemic cells (MELC) exposed to a range of CRS concentrations over three exposure conditions: short-term (4 h), long-term (24 h), and short-term with recovery (4 h+/19h-). At 0.5-1.0 micromolar CRS, 4 h exposure results in a reversible G2-phase block, while 24 h exposure results in > G2 polyploidy. At 5-10 micromolar CRS concentrations, cells exhibit persistent retardation of S-phase progression or irreversible G2 and/or > G2 blocks, depending on duration of exposure. Cells terminally blocked in G2 exhibit increased nuclear/cellular volumes and increased nuclear fluorescein isothiocyanate (protein) staining, suggestive of unbalanced growth. At 25-50 micromolar CRS concentrations, MELC exhibit severe membrane perturbation (loss of viability) regardless of exposure. In contrast, following similar exposures to an inactive isomer of CRS, MELC exhibit minimal cell cycle effects, suggesting that cell cycle kinetics may be a useful criterion for assessing potential efficacy. Taken together, these results suggest that drug toxicity can vary with both concentration and duration of exposure and, as such, a selective multiple-exposure FCM analysis may better represent the spectrum of drug action for drug development and pharmacodynamic studies.