We compared the phosphorylation of MAPK/ERK pathway of patient sample 2 (data not shown) with our recently published CML cell line phosphorylation data.23 MEK1/2 was more phosphorylated in cell lines but the phosphorylation of downstream targets ERK1/2 and CREB was more pronounced in patient sample. The gene discussed is CREB1; the disease is chronic myelogenous leukemia, BCR-ABL1 positive.