SFRP1 and breast cancer: The research by Balázs Gyȍrffy et al., on the other hand, indicates that under the drive of methylation, the phenomenon of decreased SFRP1 expression can be used to predict the poor prognosis of patients with ER1/HER22 breast cancer (BCs) [57].Therefore, in this paper, we focused on the study of promoter methylation to screen genes.We combined transcriptome sequencing and MethylRAD-seq results to select common DEGs.