Characteristics of primary de novo AML cells. Cells were grown on stroma in the absence of drug for 4 days, followed by a 3-day treatment with either 100nM AraC or 100nM DAC. (A) Fold change of cells during the 3 days of drug treatment. (B) Fraction of cells that excluded 7-AAD, relative to the mock treated samples. (C) LC-MS/MS determination of 5-methylcytosine; all values are shown relative to the percentage methylcytosine in the untreated samples. (D) Measurement of H19 mRNA using the nanostring platform; fold change is shown relative to the mock treated cells. Data points in panels A through C represent the mean of technical replicates (n = 3). mRNA measurements were performed in duplicate. Error bars represent 95% confidence intervals.