Using quantitative real time PCR and the ΔΔCt method for results analysis we could demonstrate that the expression of μ-calpain gene (CAPN1, Fig 4A) was significantly higher the ALL blasts compared to the B cells from the control group (mean fold change ALL vs control = 2.3), while the expression of both m-calpain (CAPN2, Fig 4B) and calpastatin (CAST, Fig 4C) genes did not differ between the compared groups (fold changes 0.93 and 0.895 respectively). This evidence concerns the gene CAST and acute lymphoblastic leukemia.