FBXL2 induces G0 arrest in leukemic cell lines. (A-D) THP1, U937, K562, and MOLM-13 cells were cultured in RPMI medium followed by overexpression of FBXL2 using a GenomONE HVJ-E transfection kit. Cells were labeled with BrdU and analyzed by 2-color flow cytometry (left panels). Quantification of each cell phase is presented in the bar graphs (middle panels). Cells were also collected after transfection, cyclin Ds and FBXL2 protein levels were analyzed by immunoblotting (right immunoblots). Cells were also labeled with annexin V and analyzed by 2-color flow cytometry (far right panels). Apoptotic cells were quantified. *P < .05 versus empty plasmid.