Overlapping genes between the oligonucleotide microarray dataset derived from Meg-01 shRNA stable clones and the Affymetrix microarray dataset derived from primary DS and non-DS AMkL patient blasts. (A) Differentially expressed genes identified by oligonucleotide microarray from Meg-01–negative and RUNX1 1-1 cells (left circle) were cross referenced, by comparing GenBank accession numbers, with genes differentially expressed between primary DS and non-DS AMkL patient specimens identified by Affymetrix microarray (right circle) in our previous study.27 A total of 351 probes (supplemental Table 7) were identified in both microarray datasets (overlapping area), including PIK3CD. (B) Transcript levels for PIK3CD were quantitated by real-time RT-PCR in the Meg-01 shRNA stable clones to validate the oligonucleotide microarray data. Real-time PCR results were expressed as mean values from 3 independent experiments with the same cDNA preparation and normalized to 18S rRNA. **Statistically significant differences (P < .005). Error bars indicate SEs. (C-D) PIK3CD transcript levels in primary DS and non-DS AMkL blasts were quantitated by real-time RT-PCR. Median PIK3CD transcript levels were compared between the 2 patient groups with the use of the nonparametric Mann-Whitney U test (C), and their relation to RUNX1b transcript levels was determined by the nonparametric Spearman rank correlation coefficient (D).
