Several SPTinhibitors that block tumor growth have been identified.For instance, myriocin (ISP-1), a potent SPT inhibitor(Glaros et al., 2007), has been shown to suppress the growthof breast cancer cells (Ogretmen, 2018) and B16F10 melanomacells by arresting the G2/M phase (Lee et al., 2011).Similar effects have been observed in human lung adenocarcinoma(HCC4006) cells, where SPT inhibition correlateswith growth suppression (Sano et al., 2017). This evidence concerns the gene AGXT and breast cancer.