Figure 4

miR-125b promotes cell proliferation and inhibits apoptosis in leukemic cell lines NB4 and HL60. (A) Time-dependent effects of miR-125b on NB4 cell proliferation were confirmed using an MTT assay. (B) Time-dependent effects of miR-125b on HL60 cell proliferation were confirmed using an MTT assay. At least three independent experiments were performed and similar results were obtained. Data are represented as means ± SD from 3 independent experiments. P < 0.05, compared with mock, scrambled duplex and miR-195 at 48, 72 and 96 hrs. (C) Apoptosis in a leukemic cell line transfected with miR-125b duplex, as detected by flow cytometry. Upper panel: The NB4 cells were transfected with 100 nM scrambled duplex, miR-195 or miR-125b duplex, respectively. Lower panel: The NB4 cells were transfected with 100 nM antisense control, miR-195 or miR-125b antisense, respectively. Forty-four hours following transfection, camptothecin was added to induce cells for four hours and then cells were labeled with Annexin V/PI and analyzed by flow cytometry. Three independent experiments were performed and similar results were obtained.