Interestingly, the mechanisms of action of BCAT1 and BCAT2 differ in different subtypes of BC, and the expression of BCAT1 was significantly associated with HER2+ and luminal B subtypes; and BCAT2 was significantly associated with luminal A subtype; this finding will be strong support for gene-targeted therapy of different subtypes of BC. The gene discussed is BCAT1; the disease is breast cancer.