ESR1 and breast cancer: This included 7 breast cancer-related genes (Table 2): caspase 8 (CASP8), cadherin 1 type 1 (CDH1), estrogen receptor 1 (ESR1), ETS variant 6 (ETV6), forkhead box A1 (FOXA1), GATA-binding protein 3 (GATA3) and neurotrophic tyrosine kinase receptor type 3 (NTRK3).