Summary
An investigation was made of ethoxyresorufinO-deethylase (EROD) activity, a cytochrome P450 (CYP) dependent enzyme mainly catalyzed by CYP1A1, glutathioneS-transferase (GST) activity toward the substrates 1-chloro-2,4-dinitrobenzene (CDNB) and ethacrynic acid (EAA), reduced glutathione (GSH) levels, and antioxidant enzyme (AOE) activity namely catalase (CAT) and selenium-dependent glutathione peroxidase (Se-GPx) in tumor and surrounding tumor-free (normal) tissues in female breast cancer patients. Wide interindividual variations were found in the enzyme activities in both tumor and normal breast tissues. No significant differences were noted between mean EROD and CAT activities in tumor and normal breast tissues. The mean activities of CDNB GST, EAA GST and Se-GPx and GSH levels in tumor tissue were significantly higher than those in normal breast tissue. These results show that CYP, GST and AOE behave differentially in breast tumors.
Similar content being viewed by others
References
Davis D.L., Bradlow H.L., Wolff M., Woodruff T., Hoel G., Anton-Culver H. (1993): Medical hypothesis:-xenoestrogens as preventable causes of breast cancer. Environ. Health Perspect., 101, 372–378.
Nelson D.R., Koymans L., Kamataki T., Stegeman J.J., Feyereisen R., Waxman D.J., Waterman M.R., Gotoh O., Coon M.J., Estabrook R.W., Gunsalus I.C., Nebert D.W. (1996): P450 superfamily: pdate on new sequences, gene mapping, accession numbers and nomenclature. Pharmacogenetics, 6, 1–42.
Nedeleva M.J., Gut I. (1994): P450 in the rat and man: methods of investigation, substrate specificities and relevance to cancer. Xenobiotica, 24, 1151–1175.
Parke D.V., Ioannides C., Lewis D.F.V. (1991): The role of the cytochromes P450 in the detoxication and activation of drugs and other chemicals. Can. J. Physiol., 69, 537–549.
Gulick A.M., Fahl W.E. (1995): Mammalian glutathione S-transferase: regulation of an enzyme system to achieve chemotherapeutic efficacy. Pharmacol. Ther., 66, 237–257.
Ketterer B., Mulder G.J. (1990): Glutathione conjugation. In: (Mulder G.J., Ed) Conjugation Reactions in Drug Metabolism. London, Taylor and Francis, 307–364.
Sun Y. (1990): Free radicals, antioxidant enzymes and carcinogenesis. Free Radical Biol. Med., 8, 583–599.
Çoban T. (1995): The investigation of antioxidant enzyme activities in breast tumor tissues. Ph.D. thesis, Ankara University, Ankara, Turkey.
Çoban T., Bedük Y., Iscan M. (1996): In vitro effects of cadmium and nickel on glutathione, lipid peroxidation and glutathione S-transferase in human kidney. Toxicol. In Vitro, 10, 241–245.
Burke M.D., Thompson S., Elcombe C.R., Halpert J., Haaparanta T., Mayer R.T. (1985): Ethoxy-, pentoxy-and benzyloxyphenoxazones and homologues: a series of substrates to distinguish between different induced cytochromes P450. Biochem. Pharmacol., 34, 3337–3345.
Habig W.H., Pabst M.J., Jacoby W.B. (1974): Glutathione S-transferases. The first enzymatic step in mercapturic acid formation. J. Biol. Chem., 249, 7130–7139.
Sedlak J., Lindsay R.H. (1968): Estimation of total protein-bound and non protein sulfydryl groups in tissue with Ellmann’s reagent. Anal. Biochem., 25, 192–205.
Brannon R. (1981): Regional distribution of catalase in rat brain. J. Neurochem., 36, 307–309.
Lawrence R., Burk R. (1976): Glutathione peroxidase activity in selenium-deficient rat liver. Biochem. Biophys. Res. Commun., 71, 952–958.
Lowry O.H., Rosebrough N.J., Farr A.L., Randall R.J. (1951): Protein measurement with the Folin phenol reagent. J. Biol. Chem., 193, 265–275.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Íscan, M., Çoban, T., Bülbül, D. et al. Xenobiotic metabolizing and antioxidant enzymes in normal and neoplastic human breast tissue. Eur. J. Drug Metab. Pharmacokinet. 23, 497–500 (1998). https://doi.org/10.1007/BF03190001
Issue Date:
DOI: https://doi.org/10.1007/BF03190001