MEIS1 and acute myeloid leukemia: According to above analysis and inter-relationship of gene expression level, we further stratified cytogenetic intermediate risk intermediate AML patients into 4 groups: (1) low risk: biallelic CEBPA mutations; (2) intermediate risk I: low MECOM and MEIS1 expression without biallelic CEBPA mutations or NPM1-mut/DNMT3A-wt; (3) intermediate risk II: others; (4) high risk: FLT3-ITD/TKD with the absence of NPM1-mut/DNMT3A-wt or DNMT3A mutations or high MECOM and MEIS1 expression (Fig. 3).