This can explain both the decline in the relative activity of plasminogen (that is, essentially plasmin) in plasma from patients with latter stages of BC, and the corresponding trend found for the plasma plasminogen levels (due to NE-dependent cleavage of this protein), as well as a decrease in the percentage of heavy and light plasmin chains in serine proteases fractions obtained from BC patients plasma (because plasmin is not formed in the usual amount). The gene discussed is PLG; the disease is breast cancer.