Carcinogenicity of 4-nitrosoquinoline 1-oxide and its possible role in carcinogenesis by 4-nitroquinoline 1-oxide.

4-Nitrosoquinoline 1-oxide induced malignant tumors at the subcutaneous site of injection in mice. It affected Escherichia coli to induce the so-called UV-type lesion in cellular DNA. DNA base-quinoline adducts produced by the treatment of mammalian cellular DNA with this carcinogen were proved to be identical with those obtained by the action of 4-nitroquinoline 1-oxide. Although this carcinogen was reactive enough to modify DNA chemically by itself, a different DNA modification took place in a chemical process from thos obtained in the in vivo process.