Figure 2. Cdkn1a variant 2 increases as cells acquire senescent phenotypes in culture. Time course of (A) p21var1 and p21var2 levels and (B) p16Ink4a and lamin B1 mRNA levels after 15 Gy irradiation. 2-way ANOVA test was applied. Time course of (C) p21var1 and p21var2 levels and (D) p16Ink4a and lamin B1 levels after a 24 h exposure to 250 nM doxorubicin. 2-way ANOVA test was applied. (E) p21var1 and p21var2 levels in MDFs after treatment with 10 μM nutlin-3a. (F) mRNA levels 3 hours after treatment with increasing doses of nutlin-3a. (G) mRNA levels 3 hours after irradiation (15 Gy) and treatment with increasing doses of nutlin-3a. Mean ± SEM is shown. Note Y axes are log-2 scales. * p < 0.05, ** p < 0.01, *** p < 0.001.