ASS1 and hepatocellular carcinoma: This correlation suggests that induction of hypoxia in HCC tissue during treatment with ADI-PEG 20 (for example, by TACE or TKI) may improve the therapeutic efficacy of ADI-PEG 20, and HCC patients harboring the WWOX-rs13339697-GG genotype should have further reduction of ASS1 levels and correspondingly further increase of tumor susceptibility to ADI-PEG 20 (Figure 8B).