MAPK1 and chronic myelogenous leukemia, BCR-ABL1 positive: Thus, we have provided direct evidence that such treatment can efficiently downregulate RAS/RAF/MAPK/ERK and STAT5 signaling in PTPN11-mutated CD34+ CML-BC cells (not carrying BCR-ABL1 mutation) with RAS/RAF/MAPK and STAT5 hyperactivation.