Most polyamine metabolism genes (ATP13A2, AZIN1, AZIN2, OAZ1, OAZ2, OAZ3, AOC1, PAOX, SAT1, SMOX, SRM, SMS, and AGMAT) were highly expressed in BC In contrast, AMD1, ODC1, SAT2, and ARG1 showed lower expression in cancer tissues (Figure 2A). This evidence concerns the gene AZIN2 and cancer.