Identification of novel prognostic risk signature of breast cancer based on ferroptosis-related genes.

Ferroptosis is a type of cell regulated necrosis triggered by intracellular phospholipid peroxidation, which is more immunogenic than apoptosis. Therefore, genes controlling ferroptosis may be promising candidate biomarkers for tumor therapy. In this study, we investigate the function of genes associated with ferroptosis in breast cancer (BC) and systematically evaluate the relationship between ferroptosis-related gene expression and prognosis of BC patients from the Cancer Genome Atlas database. By using the consensus clustering method, 1203 breast cancer samples were clustered into two clearly divided subgroups based on the expression of 237 ferroptosis-related genes. Then differentially expressed analysis and least absolute shrinkage and selection operator were used to identify the prognosis-related genes. Furthermore, the genetic risk signature was constructed using the expression of prognosis-related genes. Our results showed that the genetic risk signature can identify patient subgroups with distinct prognosis in either training cohort or validation, and the genetic risk signature was associated with the tumor immune microenvironment. Finally, the Cox regression analysis indicated that our risk signature was an independent prognostic factor for BC patients and this signature was verified by the polymerase chain reaction and western blot. Within this study, we identified a novel prognostic classifier based on five ferroptosis-related genes which may provide a new reference for the treatment of BRCA patients.