Overall survival (OS) and event-free survival (EFS) in HOVON/SAKK AML patients according to CXXC5 expression. (A) Survival according to microarray-based CXXC5 expression (n = 498). CXXC5 expression below the median (lower): median OS of 30 months (95% CI, 4-57); CXXC5 expression above the median (higher): median OS of 15 months (95% CI, 12-18). CXXC5 lower: median EFS of 14 months (95% CI, 10-18); CXXC5 higher: median EFS of 9 months (95% CI, 7-10). (B) Survival according to RT-qPCR expression (n = 231). Lower and higher CXXC5 expression groups were defined according to the median CXXC5 expression value, determined by the mean cycle threshold difference (∆CT) to ABL, expressed as 2^∆Ct. Jurkat RNA was used to calibrate between runs. CXXC5 was more highly expressed than ABL, with a ∆CT of 2.3 at the median CXXC5 level.