Enhancement of pancreatic tumorigenesis of 4-hydroxyaminoquinoline 1-oxide by ethionine in rats.

The effect of ethionine on pancreatic tumorigenesis of 4-hydroxyaminoquinoline 1-oxide (4-HAQO) in rats was studied. The high incidence of hyperplastic nodules developed in the exocrine pancreas of animals receiving a single injection of 4-HAQO only or protein-deficient diet containing 0.5% ethionine for 4 days followed by 4-HAQO. The incidence of adenoma was higher than that of hyperplastic nodules and well-differentiated adenocarcinoma developed in 1 out of 12 animals receiving protein-deficient diet containing ethionine for 18 days followed by 4-HAQO. No tumor was found in the pancreas of animals that received 0.005N HCl without 4-HAQO. These results suggest that the pancreatic tumorigenesis of 4-HAQO is enhanced by ethionine.