Induction of p53-downstream target genes PUMA, BAX, and CDKN1A (p21) after fludarabine administration. Quantitative PCR data show induction related to untreated control (set at 100%). Fludarabine was used in the concentration 3.6 μg/mL for 24 hours. TP53-2A indicates biallelic TP53 inactivation; 1, del/R249G; 2, del/V216M; 3, del/L132R. TP53-1, monoallelic TP53 inactivation; 1, wt/L194R; 2, wt/Y234N; 3, wt/D281N; 4, wt/C176W; 5, wt/C277F; 6, wt/A138P; and WT, no TP53 abnormality.