Figure 4. piR-8041 treatment of U87 cells inhibits cell cycle progression by approximately 25% and induces apoptosis.

(A) Cell cycle distribution 48 hours post-piR-8041 or NC-treatment. Cell cycle phases were determined by flow cytometric analysis of DNA content by staining with propidium iodide. Representative cell cycle distributions of NC- and piR-8041-treated U87 cells are shown at right with modeled phase fractions superimposed on DNA content histograms. (B) Proportions of U87 cells in early or late apoptosis/necrosis 48 hours post-piR-8041 or NC-treatment. Early apoptotic cells were defined as those stained with Annexin V but excluding PI, late apoptotic/necrotic were cells stained with both probes; representative plots are shown at right. NS, not significant; ^*, P < 0.05; ^**, P < 0.01; error bars denote standard deviation of triplicate experiments.