Figure S1. AML550 and AML719 arrays Figure S1. AML550 and AML719 arrays. (A) The AML550 array probed for total p53 is shown. The slide contains 537 AML samples form 423 patients. The enlarged area in the red box shows high p53 expression in many cell lines with known TP53 mutations (right column). Note that several patient cases have staining similar to the cell lines known to have mutations. (B) A slide of the AML719 array probed for total p53 is shown. Every sixth column, starting from the far right, is a mixture of 11 cell lines and shows very strong p53 expression since many of them carry mutant TP53. AML719 displays many cases with p53 expression similar to that observed in cell lines carrying mutant TP53 alleles. For both slides each case has 5 dots in a horizontal row showing 5 serial 1:2 dilutions (full, 1/2, 1/4, 1/8 and 1/16th strength, equivalent to 85, 42, 21, 10 and 5 cell equivalents of protein) . A B

Figure S2. Protein expression levels in cryopreserved and fresh bone marrow aspirate (BMA) and peripheral blood (PB) derived AML samples.

Figure S3. Correlation of p53 expression with cytogenetics in AML Figure S3. Correlation of p53 expression with cytogenetics in AML. The heat map displays the expression of a series of proteins probed in the AML719 array according to the presence of specific cytogenetic alterations. The highest levels of p53 expression were observed in patient samples carrying poor risk cytogenetics (i.e. -5, -7, -5/-7).

Figure S4. Overall survival for the entire cohort of patients Figure S4. Overall survival for the entire cohort of patients. Red ticks denote censored events.

A B Median OS (weeks) No. censored Total No. p53 low 51.7 73 376 Figure S5. Impact of p53 protein expression level on clinical outcomes of patients with AML. (A) Effect of p53 protein level on overall survival. (B) Effect of p53 protein level on remission duration. Data generated using a p53 protein expression cutpoint of 0.8. A B Median OS (weeks) No. censored Total No. p53 low 51.7 73 376 p53 high 34.1 37 39 Median OS (weeks) No. censored Total No. p53 low 49.5 82 210 p53 high 27 3 21

Figure S6. p53 protein expression levels in clinical samples Figure S6. p53 protein expression levels in clinical samples. Relative to normal CD34+ bone marrow cells, G-CSF primed CD34+ cells, or normal PBMC. Most AML patients had lower than normal levels of p53 protein expression. The frequency of TP53 mutations in patients with low and high p53 protein expression is shown according to different cutpoints (0.4, 0.8, and 1.1). Regardless of the cutpoint employed the overwhelming majority of TP53 mutations cluster to the group of patients with the highest p53 expression, with only 2 TP53 mutations found among patients with low p53 levels. Below Cutpoint # Mutated/Total Above Cutpoint Cutpoint New Relapsed Total 0.4 2/71 0/2 2/73 16/48 1/7 17/55 0.8 2/84 0/3 2/87 16/35 1/6 17/41 1.1 2/91 0/4 2/95 16/29 1/4 17/33

Figure S7. Clinical outcomes for patients with intermediate risk cytogenetics AML in different progeny clusters according to FLT3 mutational status. (A) Overall survival in patients with mutant FLT3. (B) Overall survival of patients with wild-type FLT3. (C) Complete remission duration in patients with wild-type FLT3. A B C

Figure S8. Complete response duration for patients with AML and high protein expression of p53, Mdm2, or Mdm4 according to cytogenetic risk group. (A) All patients. (B) Intermediate risk cytogenetics. (C) Unfavorable risk cytogenetics. A B C