Fig. 4: sPIRp21 cooperates with DNA damaging agents in killing cancer cells.
A Representative images of DAPI-stained U2OS cells transduced with either EV or sPIRp21 particles. 48 h later, cells were either mock treated (NT) or treated with UV (5 J/m2), CDDP (1 μM), HU (0.25 mM) or olaparib (0.65 µM) and fixed 6 days later. B Cell number (mean ± SD) expressed as fold changes with respect to the EV transduced, mock treated (NT) U2OS cells shown in (A). The total cell number in 3 wells from a 96-well plate was quantified for each condition. N = 3 (Statistics: one-way ANOVA, Tukey post test). C Representative images of U2OS cells transfected with GFP-Pol η, showing either its pan-nuclear (negative) or its focal (positive) organization. D Percentage (mean ± SD) of U2OS cells with nuclear GFP-Pol η foci. U2OS cells were transfected with GFP-Pol η and 5 h later transduced with EV, sPIRp21 and sPIRp21ΔP. 48 h later, cells were mock-treated (NT) or treated with UV (40 J/m2), CDDP (33 μM), HU (2 mM) and fixed 5 h later. Cells treated with Ola (0.65 µM) were fixed 24 h after the addition of Ola. At least 200 nuclei positive for both GFP and myc/sample were analyzed. N = 3 (Statistics: one-way ANOVA, Tukey post test).
