Acute phase reactant proteins (APPs), such as positive APPs [including α1-antitrypsin (AAT), α1-antichymotrypsin, haptoglobin, ceruloplasmin, C3, and C-reactive protein (CRP)] and negative APPs (comprising albumin, prealbumin, and transferrin) serve as inflammatory biomarkers predicting cancer patient outcomes (32). Here, C3 is linked to cancer.