SRM and cancer: 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).