Accession Number : ADB233113
Title : Dietary Carcinogens and Breast Cancer.
Descriptive Note : Annual rept. 1 Jul 96-30 Jun 97.
Corporate Author : UNIVERSITY OF SOUTH ALABAMA MOBILE
Personal Author(s) : Gaubatz, James W.
Report Date : JUL 1997
Pagination or Media Count : 27
Abstract : We have investigated phase II activation of the food-derived mutagen 2-hydroxyamino-1-methyl-6-phenyl4,5-Bpyridine (N-OH-PhIP) by cytosolic acetyltransferase, sulfotransferase, and tRNA synthetase/kinase enzymes from human breast tissue. Cytosol from homogenates of mammary gland tissue obtained from breast reduction surgery or mastectomy was incubated with and without enzyme-specific cofactors, and mutagen binding to calf thymus DNA was quantified by 32P-postlabeling. In addition, microsomal fractions of mammary epithelial cells from some individuals were examined for prostaglandin H synthetase activation of N-OH-PhIP. Our results show that all four enzymes can participate in activating N-OH-PhIP, thus inducing PhIP-DNA adduct formation in human mammary cells. However, not all individuals exhibited all these activities; instead each individual showed a combination of one or more activation pathways. The present findings provide the first demonstration that the human mammary gland has the capacity to metabolically activate a dietary mutagen by alternative enzyme systems, including acetyltransferase, sulfotransferase, tRNA synthetase/kinase and prostaglandin hydroperoxidase catalysis.
Descriptors : *CARCINOGENS , *DIET , *BREAST CANCER , ACTIVATION , EPITHELIUM , TISSUES(BIOLOGY) , DEMONSTRATIONS , ENZYMES , CLINICAL MEDICINE , DEOXYRIBONUCLEIC ACIDS , CATALYSIS , HUMAN BODY , INFECTIOUS DISEASES , MEDICAL SERVICES , DEATH , SURGERY , PREGNANCY , CELLS(BIOLOGY) , BOVINES , RIBONUCLEIC ACIDS , MAMMARY GLANDS , PARTIAL BODY IRRADIATION , PROSTAGLANDIN , THYMUS , MASTECTOMY.
Subject Categories : ANATOMY AND PHYSIOLOGY
MEDICINE AND MEDICAL RESEARCH
FOOD, FOOD SERVICE AND NUTRITION
Distribution Statement : APPROVED FOR PUBLIC RELEASE