Catalase-silenced BT-20 KD-CAT cells are sensitized to the toxic effect of ascorbic acid. BT-20 KD-CAT cells were significantly more affected by the exposure to high concentrations of ascorbic acid (50 and 100 mmol/L) than BT-20 Ctrl cells. The results shown are representative for 3 independent analyses. Values are expressed as mean ± standard deviation. *p < 0.01.