RAF1 and chronic myelogenous leukemia, BCR-ABL1 positive: Therefore, two CML cell lines, K562 and LAMA-84, were used to assess the phosphorylation of STAT5 and ERK (effector kinase of the RAS/RAF/MAPK pathway) and members of the AKT/mTOR/S6 and GSK3β signaling pathways in response to imatinib alone, ISRIB alone and imatinib combined with ISRIB.