CD34 and B-cell chronic lymphocytic leukemia: Thus, using quantitative reverse transcription-PCR, we found significantly higher mRNA expression levels of c-MYC in CD34+ cells from NOTCH1 mutated and WT CLL samples compared to HD (3.5 ± 0.7 and 2.6 ± 0.08 vs 1.3 ± 0.1) (Figure 1Diii).