Figure 6: A modest miR-17-19b induction reduces the aggressiveness of MYC-dependent Burkitt lymphoma.

(a) Phenotypic characterization of miR-17-19b-overexpressing B-lymphoma cells. In vitro growth of λ-MYC lymphoma lines (#2567 and #2646) infected with retroviruses expressing miR-17-19b or control virus (left panel). Cell cycle profiles of #2567 cells, assayed by flow cytometry after a short BrdU pulse (middle panel). Apoptosis rate in control and miR cells evaluated by caspase-3/7 activity assay (right panel). Results represent the averages±s.e.m. from three independent experiments (t-test, one-tail, equal and unequal variances for cell cycle and apoptosis, respectively, **P≤0.01; ***P≤0.001). (b,c) miR-17-19b-overexpressing cells are outcompeted by control, when co-cultured both in vitro (b) and in vivo (c). Results are represented as % of miR cells relative to the entire population, normalized to the input (see Methods for details of the experiment). For in vitro experiments, bar graphs represent the averages±s.e.m. from three independent experiments, while for in vivo experiment one sample per animal was analysed in triplicate.