Altered nuclear RNA transport associated with carcinogen intoxication in rats

The release of nuclear restricted RNA to the cytoplasm in dimethylaminoazobenzene (DAB) and acetylaminofluorene (AAF) induced tumors suggested a basis for the phenotypic expression of chemically induced neoplasms. In this report the increased release of RNA from nuclei $\text{in vitro}$ is identified both following acute intoxication and with prolonged (tumor producing) exposure to a third carcinogen, thioacetamide. This release is independent of ATP added in the cell-free system and consistent with “leaky” nuclei, providing further support for the hypothesis that nuclear RNA transport is involved in chemical carcinogenesis.