The risk score = (0.1843) * DLAT + (− 0.4056) * SLC31A2 + (0.7899) * SLC25A3 + (0.4987) * ATOX1. The risk score, survival status and expression of patients with HER2-positive BC were shown in Fig. 3C. The further OS curve analysis showed that patients in the low-risk group had a lower risk of death and longer survival time (HR = 0.31, p = 0.026, Fig. 3D). Here, SLC31A2 is linked to breast cancer.