Moreover, we compared the differences in the expression of SOX4 molecules among the four molecular subtypes in the TCGA-BRCA dataset and found that the expression of SOX4 was significantly greater in tumours than in normal tissues, with higher expression levels in the basal and HER2 subtypes (Fig. 3j), and its expression level had better prognostic stratification significance in the basal and HER2 subtypes (Fig. 3k). Here, ERBB2 is linked to neoplasm.