By measuring luciferase activity in real time, Justyna Magdalena Przystal et al. (Przystal et al., 2018) evaluated tumor growth and regression efficacy in vivo and in vitro after treated by the combination therapy of TMZ and ADI-PEG20, finding an obvious elevation of anti-GBM activity irrespective of ASS1 status. This evidence concerns the gene ASS1 and glioblastoma.