Glutathione, thioredoxin, and peroxiredoxin-1 are depleted in high superoxide–producing AML blasts. (A) GSH levels in normal human CD34⁺ cells (n = 3) compared with primary AML blasts (n = 22). (B) Superoxide production by normal CD34⁺ cells and primary AML blasts in relation to GSH levels. (C) Thioredoxin (Trx) and peroxiredoxin-1 (Prx-1) expression in primary AML blasts in relation to their superoxide production. Expression levels in normal CD34⁺ cells are also indicated. Actin expression indicates relative protein loading. The significance of difference was determined by the Mann-Whitney U test. **P < .01.