Both PBX3 and MEIS1 are functionally important target genes of miR-495 in MLL-rearranged leukemic cells. (A) Analysis of the effects of forced expression of miR-495 (MSCV-PIG-miR-495+MSCVneo), PBX3 (MSCV-PIG+MSCVneo-PBX3), PBX3+miR-495 (MSCV-PIG-miR-495+MSCVneo-PBX3), MEIS1 (MSCV-PIG+MSCVneo-MEIS1), and MEIS1+miR-495 (MSCV-PIG-miR-495+MSCVneo-MEIS1), respectively, on cell viability (Upper) and apoptosis (Lower) of MONOMAC-6 cells. Cell viability and apoptosis were detected 48 h after transfection. (B) Analysis of their effects on cell growth/proliferation of MONOMAC-6 cells. Cell numbers were counted every day after transfection for 6 d. The coding regions (CDS) of PBX3 and MEIS1 were cloned into MSCVneo, and thus their ectopic expression would not be repressed by endogenous or cotransfected miR-495. The cells transfected with MSCV-PIG+MSCVneo (Ctrl) were used as controls. *P < 0.05; **P < 0.01, two-tailed t test.