To sum up, the levels of serum TGF- β 1, MMP-9 and IL-1 β in subjects with BC are increased, and the levels of TGF- β 1 and MMP-9 are related to clinical stage, lymph node metastasis, histological grade and molecular classification, which can effectively predict the prognosis of subjects. The gene discussed is MMP9; the disease is metastatic malignant neoplasm in the lymph nodes.