Downregulation of p16^INK4A expression is correlated with lifespan extension promoted by the continuous presence of rapamycin.

The fold reduction in p16INK4A protein expression and in IL6 and IL8 secretion, and the fold increase in NANOG gene expression between untreated and rapamycin-treated BM09, BM13, BM16 and BM18 samples at passages when untreated cells entered replicative senescence (deviation passage), or in the case of BM12 at the same senescence passage, were plotted against the additional PD number obtained for the corresponding rapamycin-treated cells and statistically analyzed by Spearman correlation, as shown in the graphs.