TOX suppression leads to increased apoptosis and caspase activation in CTCL cells. (A) FACS analysis of apoptotic (annexin V–positive) cell population in TOX-sh Hut78, HH, and SZ4 cells compared to control (CTR) cells. (B) Percentages of apoptotic cells in TOX-sh Hut78, HH, and SZ4 cells compared to CTR cells. **P < .01 by 2-tailed Student t test with Welch correction. Error bars indicate standard error of the mean. Data depicted are representative of at least 4 independent experiments. (C) Comparison of caspase 9 and caspase 3 levels (both full-length and cleaved) in TOX-sh and CTR cells. PI, propidium iodide.