DNA Adduct Profiles Predict in Vitro Cell Viability after Treatment with the Experimental Anticancer Prodrug PR104A.

Abstract

PR104A is an experimental DNA-alkylating hypoxia-activated prodrug that can also be activated in an oxygen-independent manner by the two-electron aldo-keto reductase 1C3. Nitroreduction leads to the formation of cytotoxic hydroxylamine (PR104H) and amine (PR104M) metabolites, which induce DNA mono and cross-linked adducts in cells. PR104A-derived DNA adducts can be utilized as drug-specific biomarkers of efficacy and as a mechanistic tool to elucidate the cellular and molecular effects of PR104A. Toward this goal, a mass spectrometric bioanalysis approach based on a stable isotope-labeled adduct mixture (SILAM) and selected reaction monitoring (SRM) data acquisition for relative quantitation of PR104A-derived DNA adducts in cells was developed. Use of this SILAM-based approach supported simultaneous relative quantitation of 33 PR104A-derived DNA adducts in the same sample, which allowed testing of the hypothesis that the enhanced cytotoxicity, observed by preconditioning cells with the transcription-activating isothiocyanate sulforaphane, is induced by an increased level of DNA adducts induced by PR104H and PR104M, but not PR104A. By applying the new SILAM-SRM approach, we found a 2.4-fold increase in the level of DNA adducts induced by PR104H and PR104M in HT-29 cells preconditioned with sulforaphane and a corresponding 2.6-fold increase in cytotoxicity. These results suggest that DNA adduct levels correlate with drug potency and underly the possibility of monitoring PR104A-derived DNA adducts as biomarkers of efficacy.

• Authors: Alessia Stornetta, Peter W Villalta, Frederike Gossner, William R Wilson, Silvia Balbo, Shana J Sturla
• Journal: Chemical research in toxicology (Chem Res Toxicol) Vol. 30 Issue 3 Pg. 830-839 (03 20 2017) ISSN: 1520-5010 [Electronic] United States
• PMID: 28140568 (Publication Type: Journal Article, Validation Study)

Chemical References

• Antineoplastic Agents
• DNA Adducts
• Nitrogen Mustard Compounds
• PR-104A
• Prodrugs

Topics

• Antineoplastic Agents (pharmacology)
• DNA Adducts
• HT29 Cells
• Humans
• In Vitro Techniques
• Nitrogen Mustard Compounds (pharmacology)
• Prodrugs (pharmacology)