[Change in acetylation activity in 7,12-dimethylbenz(alpha)-anthracene induction]

In mice, injected DMBA subcutaneously 12 weeks prior to sarcomas detection, an increased activity of N-acetyltransferase was noted. As a result of DMBA application into mice skin the increased activity of this enzyme was noted 16 weeks prior to the appearance of papillomas and cancer of skin. Initial increase of the enzyme activity was followed by its considerable decrease and terminated by a new increase in the detection of tumors. The causes of the changes in the activity of N-acetyl-transferase are discussed, as well as the possibility to consider these changes as a sign indicating that tumor is likely to appear in the nearest future.