WWOX and hepatocellular carcinoma: Notably, silencing WWOX further attenuated cell growth when cells were treated with different concentrations of ADI-PEG 20 (blue and green lines for ADI-PEG 20 concentrations at 1, 2, 4, 8, and 16 μg/mL), indicating that reduced ASS1 expression after hypoxia induction and under WWOX knockdown enhanced the susceptibility of HCC cells to ADI-PEG 20.