Fig. 3.

p27 is the driver in PML loss-induced senescence. a Experimental design for inducible p27 silencing (sh1p27 and sh2p27, B: blasticidin selection) alone or in combination with inducible PML silencing (sh4, P: puromycin selection) in MDA-MB-231 cells. b p27 and PML protein levels upon doxycycline inducible silencing of either p27 or PML or both in MDA-MB-231 cells (representative of three experiments). c Effect on the number of senescent cells (n = 4) upon p27 and/or PML inducible silencing in MDA-MB-231 cells. d Effect on the relative cell number (n = 4) upon p27 and/or PML inducible silencing in MDA-MB-231 cells. Error bars represent s.e.m. p, p-value (*p < 0.05, **p < 0.01, ***p < 0.001). One-tailed Student's t-test (c) and one-tailed one-sample t-test (d) were used for cell line data analysis. shC: scramble shRNA, Dox: doxycycline, SA-β-gal: senescence-associated beta-galactosidase. Molecular weight markers (kDa) are shown to the right