Then, we acquired ER+ breast cancer data from the TCGA database, which were quarterly ranked according to the expression level of RBP7. The high and low RBP7 expression groups were defined as the first and fourth quarters of ER+ breast cancer data, respectively, and the differential genes (|log2(FC)| > 1) between these two groups were analyzed by using the Limma software package for display as a volcano plot (Figure 7(c)). Here, ESR1 is linked to breast cancer.