Ornithine decarboxylase induction by chemically complex liquids from two solvent refined coal processes

Area of Science:

• Biochemistry
• Toxicology
• Carcinogenesis

Background:

• Ornithine decarboxylase (ODC) induction is a potential biomarker for neoplastic transformation.
• Previous studies linked ODC induction to purified carcinogens.
• Extending ODC analysis to complex mixtures is crucial for understanding carcinogenesis.

Purpose of the Study:

• To investigate ornithine decarboxylase (ODC) induction by complex mixtures from solvent-refined coal (SRC) processes.
• To compare ODC induction patterns with tumorigenicity data for these materials.
• To assess ODC as a biomarker for neoplastic transformation in response to complex chemical exposures.

Main Methods:

• Evaluation of ODC induction in mouse epidermis following topical application of SRC-I and SRC-II fractions and subfractions.
• Comparison of ODC induction kinetics and magnitude with 12-O-tetradecanoylphorbol-13-acetate (TPA).
• Dose-response and temporal analysis of ODC activity after single and multiple applications.

Main Results:

• Heavy distillate (HD), a potent carcinogen, induced ODC with kinetics similar to TPA.
• ODC induction by HD was dose-dependent and observed in both epidermal and hepatic tissues.
• All complete carcinogens tested induced ODC, though the magnitude and pattern varied.

Conclusions:

• ODC induction is a sensitive indicator for neoplastic transformation by complex carcinogenic mixtures.
• The pattern and magnitude of ODC induction correlate with the carcinogenic potential of SRC fractions.
• ODC induction serves as a valuable biomarker for assessing the biological activity of complex chemical mixtures.