Adenovirus-mediated expression of spermidine/spermine N-1-acetyltransferase gene induces S-phase arrest in human colorectal cancer cells

Institute of Biochemistry and Molecular Biology, School of Medicine, Shandong University, Jinan, P.R. China.
Oncology Reports (Impact Factor: 2.3). 12/2008; 20(5):1229-35. DOI: 10.3892/or_00000134
Source: PubMed

ABSTRACT Spermidine/spermine N1-acetyltransferase (SSAT) is a key enzyme of polyamine catabolism. In a previous study, we constructed a recombinant adenovirus, Ad-SSAT, which can express human SSAT. In the present study, we investigated the effect of Ad-SSAT on the growth and cell cycle of colorectal cancer cells. We found that Ad-SSAT increased the expression of SSAT and inhibited the growth of HT-29 and Lovo cells. The growth inhibition was caused by cell cycle arrest in the S phase. Furthermore, Ad-SSAT was shown to suppress the expression of cyclin A and nuclear factor E2F-1 in HT-29 and Lovo cells. The inhibitory effect of Ad-SSAT on cyclin A promoter activity was also observed in a reporter gene assay. Our results suggest that the expression of SSAT mediated by Ad-SSAT infection inhibits the growth of colorectal cancer cells and induces cell cycle arrest at the S phase, through a mechanism involving the suppression of cyclin A and E2F-1 expression.

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