2005 Volume 51 Issue 7 Pages 324-331
Telomerase reverse transcriptase (TERT) is acknowledged to be the rate-limiting determinant of telomerase, and transcriptional regulation of the TERT gene plays a key role in the activation of telomerase. Hamster and human TERT promoters share common protein binding sites, such as E-boxes or GC-boxes, which are for Myc and Spl, respectively. Recent studies have demonstrated that expression of human TERT (hTERT) is usually affected by Spl, but not by c-Myc.
To study the effect of transcriptional factor Spl on the transactivation of TERT, we investigated the expression of Spl and TERT mRNAs by RT PCR during carcinogenesis of the hamster tongue induced by DMBA. We attempted to gain insight into the relation between the expression of these factors.
The expression of hamster TERT mRNA strongly correlated with telomerase activity. Coincidentally, we found that the expression of Spl and hamster TERT were upregulated in dysplasia and squamous cell carcinoma tissues and were closely linked to each other. These results suggest that Spl is a crucial regulatory factor for hamster TERT transactivation during carcinogenesis of the tongue.
