Expression of SRSF1 and PRMT1 among different cytogenetic subtypes and relapsed ALL patients. (A) The expression of SRSF1 and PRMT1 in paired samples from different cytogenetic subtypes was detected, including T-cell ALL with deletion of chromosome 1 [T-del(1)], t(12;21) (TEL-AML1), t(1;19) (E2A-PBX1) and t(9;22) (BCR-ABL), and no obvious difference was found among these subtypes. (B) No obvious change was found in ND samples among these subtypes. (C) The over-expression of SRSF1 in the CR phase in a rare case (No. 16), who experienced an isolated CNS relapse 8 days after the collection of CR sample. (D) Both SRSF1 and PRMT1 expression rebounded after relapse, but remained at a normal level in the CR phase. Four relapsed cases were detected, with the result from case No. 4 being shown.