Abstract
Synthetic phenolic antioxidant β-(4-hydroxy-3,5-di-tert-butylphenyl) propionic acid,
named phenozan, is a potential antiepileptic drug. In pre-clinical trials this substance
did not manifest any toxicity, and also inhibited the development of some spontaneous
tumors in animals. The purpose of this study was to evaluate inhibiting effect of
phenozan on spontaneous carcinogenesis in rats and mice. In experiments with rats
LIO and mice SHR of local breeding, with high spontaneous tumor incidence, phenozan
was dissolved in sunflower oil and administered by gavage in therapeutic dose 5 mg/kg
3 times per week for 18 months. There were no any signs of toxicity and differences
in weight of animals during the phenozan treatment compared with the control (sunflower
oil). Phenozan significantly reduced the overall incidence and multiplicity of all
tumors but only multiplicity of malignant tumors, compared with the control. Moreover
a significant decrease of overall incidence and multiplicity was observed in pituitary
and breast tumors in females and only overall multiplicity of tumors of pituitary
and lymphoid tissue in males. In mice phenozan reduced overall incidence and multiplicity
of lung tumors (in females) and also overall multiplicity of all tumors (in females)
and only malignant tumors (in males). These findings allow us to classify phenozan
as anticarcinogenic agent. Anticarcinogenic activity of phenozan is important because
clinical study of this drug as the possible antiepileptic drug goes along and it is
known that such drugs are designed for long-term use.
Key words
synthetic phenolic antioxidant phenozan - spontaneous tumors - chemoprevention
