Sox4 and CREB are overexpressed in human AML. (A-C) Western blots with lysates from AML cell lines and pediatric AML bone marrow samples at diagnosis probed with CREB, phospho-CREB, and Sox4 antisera. Sample PZ2 is normal BM control. (D) Sox4 and CREB protein expressions are highly correlated in human AML. Protein expression of Sox4, CREB, and phospho-CREB was quantitated using reverse phase protein array using bone marrow samples from 66 patients with newly diagnosed childhood AML (age range, 0-18 years). Expression is represented as fold change relative to normal bone marrow and displayed on a logarithmic scale. Pearson correlations (r) for log protein expression are significantly different from zero (P < .0001). The first principal component (straight line) accounts for 89% of the total variation.