NF-E2 expression in MPN patients. (A) NF-E2 expression in JAK2^V617F-positive and -negative ET patients and healthy controls. (B) NF-E2 expression in JAK2^V617F-positive and -negative PMF patients and healthy controls. (A-B) RNA was isolated from purified granulocytes of 12 JAK2^V617F-positive and 11 JAK2^V617F-negative ET patients, 17 JAK2^V617F-positive and 8 JAK2^V617F-negative PMF patients, and 28 healthy controls as indicated and subjected to quantitative RT-PCR analysis for NF-E2 expression. A standard curve with known copy numbers of NF-E2 and 18S rRNA was included on each plate. Sample copy numbers of NF-E2 and 18S rRNA were determined from the standard curve and are expressed as relative ratios (copy number NF-E2 per 10⁶ 18S molecules). The median is depicted by a horizontal line; *P < .05, **P < .01, ***P < .001 by Kruskal Wallis one-way ANOVA on Ranks and Mann-Whitney Rank sum test. HC indicates healthy controls. (C) Correlation of NF-E2 and AML1 mRNA expression in 31 PV patients. P < .001.