A recent study has shown that argininosuccinate synthase 1 (ASS1) and spermidine/spermine N1-acetyltransferase (SAT1), the central enzymes for arginine metabolism, are hypermethylated in cisplatin-resistant bladder cancer cells (Yeon et al., 2018). The gene discussed is ASS1; the disease is urinary bladder carcinoma.