<i>PIM1</i> mRNA decay kinetics during mitogenic stimulation of cancer cell lines.

aCultures were incubated for 16–20 h in medium containing 0.5% serum prior to each experiment. Where indicated, cells were stimulated by adding medium containing serum (10%) and TPA (100 nM) for indicated periods prior to inhibition of transcription with actD. bFirst-order mRNA decay constants (k) were resolved for each cell population by actD time course assay as described under “Materials and Methods”. mRNA half-lives were then calculated using t1/2 = ln2/k. Quoted values represent the mean ± SD across n independent time course experiments.