tNASP depleted cells slow their progression through the cell cycle and develop apoptosis markers. A. FACS analysis demonstrating double thymidine-blocked HeLa cells allowed to progress in synchrony through the cell cycle. Solid line: HeLa cell progression through the cell cycle after treatment with tNASP shRNA; Dotted line: HeLa cell progression after treatment with scrambled shRNA. B. Immunostaining for caspase-3 in HeLa, PC-3, and PWR-1E cells after treatment with tNASP shRNA. Scale bar = 20 μm for all panels. Upper panel shows phase contrast images and lower panel shows corresponding immunostaining for caspase-3. HeLa cells (a, b); PC-3 cells (c, d); PWR-1E cells (e, f). Control caspase-3 staining of scrambled shRNA treated cells was negative for all samples (data not shown).