For example, changes in some protein expression levels can be used as the markers of early detection of B-ALL, including leucine-rich alpha-2-glycoprotein 1 (LRG1), thrombin (F2), alpha-2-macroglobulin (A2M), heparin cofactor II (SERPIND1), clusterin (CLU), alpha-1 antitrypsin (SERPINA1), complement C3 (C3), complement factor B (CFB), and alpha-2-antiplasmin (SERPINF2) (10). The gene discussed is C3; the disease is precursor B-cell acute lymphoblastic leukemia.