Figure 5.

Rapamycin did not reduce hTERT transcription but reduced hTERT protein expression. (A) The effect of rapamycin on hTERT protein expression was detected by Western Blot. SMMC-7721 cells were treated with rapamycin, or 5-Fu or both for 36 h, cell lysates were immunoblotted with hTERT antibody. (B) The effect of rapamycin and 5-Fu on hTERT promoter activity. SMMC-7721 cells were transient transfected with pBTdel-130 plasmid DNA, which contains the luciferase reporter driven by the core hTERT promoter, whole cell extract was then prepared from the cells and luciferase activity was measured by Dual-Luciferase Reporter Assay System (lands are as labeled on the figure). The mean ± SD of four experiments is shown; statistical significance shown as * and ** was determined by t test, with p > 0.05 defined as significant. (C) hTERT mRNA expression determined with RT-PCR.