Molecular Analysis of Medaka Tumors: New Models for Carcinogenicity Tests

Abstract

The broad, long-term objective of our laboratory is to use fish as a model system to better understand factors which promote tumor production and to develop a reliable and sensitive means of detecting carcinogens in aqueous environments. Studies of oncogene and suppressor gene function and their relationship to tumor production in fish will contribute to our understanding of the molecular basis of carcinogenesis. In these studies we have examined the role of these genes in tumors in Japanese medaka (Oryzias latipes) induced by specific carcinogens. The medaka has been widely used for carcinogenicity testing in the past decade. In studies described here, we used fish which were exposed to diethylnitrosamine (DEN), and methylazoxymethanol acetate (MAMAc). A significant proportion of exposed animals developed a variety of liver tumors. In contrast, fish exposed to MNNG developed extra-hepatic tumors. DNA extracted from these tumors was analyzed in transfection assays for the presence of transforming genes. We have also initiated studies on oncogene expression in normal tissue, a study of the p53 gene and are continuing the analysis of the sequence of a novel oncogene detected in a DEN-induced cholangiocarcinoma.

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Document Details

Document Type
Technical Report
Publication Date
Jul 07, 1993
Accession Number
ADA274706

Entities

People

  • Rebecca J. Van Beneden

Organizations

  • Duke University

Tags

DTIC Thesaurus Topics

  • Biomedical Research
  • Cell Line
  • Cells
  • Chemistry
  • Environment
  • Fish
  • Genetic Structures
  • Genetics
  • Materials
  • Mrna
  • Neoplasms
  • Ribonucleic Acids

Readers

  • Aquatic Ecology
  • Molecular Biology and Genetics
  • Toxicology/Environmental Toxicology