The induction of spermidine/spermine N-1-acetyltransferase (SSAT) is a common event in the response of human primary non-small cell lung carcinomas to exposure to the new antitumor polyamine analogue N-1,N-11-bis(ethyl) norspermine

Several new polyamine analogues have been developed for the treatment of hu man solid tumors. The phenotype-specific activity of some of these analogue s has been associated with the superinduction of the rate-limiting enzyme i n polyamine catabolism spermidine/spermine N-1-acetyltransferase (SSAT). Us ing immunohistochemistry, we found a majority (64%) of human primary lung c ancer explants to exhibit high expression of SSAT after treatment with 10 m u M N-1,N-11-bis(ethyl)norspermine, an agent currently undergoing Phase II clinical trials against several important human solid tumors. The staining of SSAT was found specifically in the tumor tissue and not in the neighbori ng normal lung tissue. These results demonstrate the ability to detect indu ction of SSAT in clinical specimens and suggest the potential of this test as a prognostic indicator of drug response.