The absolute abundance of various metabolic enzymes measured by an iMPAQT method in young and nutlin3a-induced senescent (n-Sen) HCA2 cells.

For senescence induction, HCA2 humn skin fibroblasts were synchronized at G2 phase by treatment with 9 uM of RO3306 (Roche) for 24 hrs, treated with 9 uM of RO3306 and 5 uM of Nutlin3a (Sigma-Aldrich) for 8 hrs, and then with 5 uM of nutlin3a for 18 hrs. Cells were then treated with 100 nM of BI-2536 for 9 days to eliminate proliferating cells, and cultured in normal media for 9 days. The senescent and non-senescent (young) cells were collected, washed with PBS, snap-frozen, and analyzed with a iMPAQT method.