The expression levels of SRSF1 and PRMT1 are dramatically up-regulated in pediatric ALL. (A) Western blot analysis of unpaired samples from 8 patients (n = 8, 4 ND and 4 CR). Both SRSF1 and PRMT1 were over-expressed in ND samples, and displayed reduced levels of expression after CR. A sample from one pediatric ALL patient with idiopathic thrombocytopenic purpura (ITP) was used as a negative control, and GAPDH was used as a loading control. (B) Western blot analysis was of paired samples taken from 35 pediatric ALL patients (n = 70). The results from 4 such patients are shown here, including 2 with t(12;21) (TEL-AML1) translocation and 2 with no translocation. Both SRSF1 and PRMT1 were over-expressed in ND samples and displayed reduced levels of expression after CR. (C) Eliminating NaF and Na3VO4 from the lysis buffer and adding calf intestinal alkaline phosphatase (CIP) resulted in no change in the upper bands of SRSF1.