Development of MDS/MPN is associated with disrupted expression of essential myeloid transcription factors. (A-C) Real-time PCR analysis of indicated transcripts using RNA isolated from CD11b⁺/Gr-1^low/− cells from MDS/MPN NR4A1^+/−NR4A3^−/− mice (n = 3, at 4-10 months, blast levels between 12% and 18%; gray columns) and control NR4A1^+/−NR4A3^+/+ mice (n = 7, at age 4-10 months; black columns). Animals with greater than 10% blasts were considered advanced diseased based on the criteria of Sokal et al and the International Bone Marrow Transplant Registry.^42,43  (D-F) Real-time PCR analysis of indicated transcripts using RNA isolated from CD11b⁺/Gr-1^low/− cells from 6-week-old preneoplastic NR4A1^−/−NR4A3^+/− mice (gray columns, n = 3) and 6-week-old NR4A1^+/+NR4A3^+/− control mice (black columns, n = 3). All results were normalized to B2m expression. *P < .05. **P < .02. Error bars represent SEM.