Figure 4. miR-21 suppresses IFN-induced apoptosis.
(A) PC3 cells and PC3 cells overexpressing miR-21 (+miR-21) were treated with IFN (1000 IU/ml for 24 h) and analyzed for apoptosis by TUNEL assays. Phase contrast and fluorescent images are on the left and right, respectively. Apoptotic cells are fluorescent and appear green in the photomicrograph. (B) PC3 cells, PC3 cells overexpressing miR-21, DU145 cells, and DU145 cells in which miR-21 was knocked down (−miR-21) were treated for 24 hr with IFN (1000 IU/ml), camptothecin (CP, 1 μM) or staurosporine (ST, 1 μM) and analyzed for apoptosis by cell death detection ELISA assays. Data represent the mean +/− SD of at least three experiments performed in duplicate.