FIGURE 5.

CD73 mediates the NMN-triggered rescue from FK866-induced cell death. A, 24 h after transfection, negative control and CD73-silenced A549 cells (5 × 10³ cells/well in 96-well plates) were incubated for 72 h in the presence or absence of 30 nm FK866, with or without 10 μm NMN or NR (added twice a day). Cell viability was evaluated by SBC. Results are expressed as a percentage of cell growth relative to untreated, control cells. Data are expressed as the mean ± S.D. (error bars) (n = 3). #, p < 0.01 compared with FK866-treated siRNA control cells; *, p < 0.05 compared with FK866 + NMN-treated siRNA control cells; †, p < 0.01 compared with FK866- and FK866 + NMN-treated siRNA CD73 cells. B, A549 and U87 cell viability (5 × 10³/well in 96-well plates) was evaluated by SBC after a 72-h incubation of the cells in complete medium with or without 30 nm FK866 in the presence or absence of 1 μm APCP or of 10 μm NMN or NR (added twice a day). Results are expressed as a percentage of cell growth relative to untreated, control cells. Data are expressed as mean ± S.D. (n = 3). *, p < 0.05; #, p < 0.01 compared with the corresponding FK866 + NMN-treated cells.