Possible Mechanism of Orotic Acid Induced Liver Tumor Promotion in the Rat

  • Ezio Laconi
  • Pier P. Coni
  • Giuseppina Pichiri
  • Prema M. Rao
  • Srinivasan Rajalakshmi
  • Dittakavi S. R. Sarma


One of the important advances in the study of experimental liver carcinogenesis is the development of model systems which permit an analysis of the initiation, promotion and progression phases of the carcinogenic process1–6. We have recently demonstrated that orotic acid (OA), a precursor for pyrimidine nucleotide biosynthesis is an effective promoter of liver6–9 and duodenal10 cancer in the rat. In view of the fact that OA is a normal cellular constituent whose levels can be perturbed in a variety of ways11 and that it had the potential to be a multiorgan tumor promoter, it became important to understand the mechanisms by which OA exerted this effect.


Partial Hepatectomy Tritiated Thymidine Cyproterone Acetate Orotic Acid Positive Focus 
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Copyright information

© Springer Science+Business Media New York 1988

Authors and Affiliations

  • Ezio Laconi
    • 1
  • Pier P. Coni
    • 1
  • Giuseppina Pichiri
    • 1
  • Prema M. Rao
    • 1
  • Srinivasan Rajalakshmi
    • 1
  • Dittakavi S. R. Sarma
    • 1
  1. 1.Department of Pathology, Medical Sciences BuildingUniversity of TorontoTorontoCanada

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