Molecular mechanisms for the regulation of aryl sulfotransferase IV expression during 2-acetylaminofluorene-induced hepatocarcinogenesis in rat.

The dietary administration of 2-acetylaminofluorene to male rats to induce hepatocarcinogenesis causes a reversible as well as persistent down-modulation of N-hydroxy-2AAF sulfotransferase activity. Studies are presented which indicate that several molecular mechanisms may be involved in the down-regulation of sulfotransferase activity and expression. These include carcinogen-mediated inactivation of sulfotransferase mRNA or protein, interference with hormonal regulation of sulfotransferase expression, and, mutation of the sulfotransferase gene.