Flow cytometry analysis showed that CD56+CD44+ and CD3+CD4+CD25+FoxP3+ cells had higher proportions in B-ALL patients than the control group (Figure 1B,C), while activation of T-cells did not alter in B-ALL cases, as the percentages of CD4+CD25+ and CD4+CD44+ cells were similar in both groups. This evidence concerns the gene CD4 and precursor B-cell acute lymphoblastic leukemia.