In short, after biomarker discovery and analytical method development, 80 plasma samples from healthy controls (HCs) and 206 plasma samples from patients with CRC were analyzed; a set of biomarkers consisting of platelet factor 4 (PF454–62), apolipoprotein E (APOE198–207) and inter-alpha-trypsin inhibitor heavy chain H4 (ITIH4429–438) showed significant differences among HCs, early-stage CRC patients, and late-stage CRC patients. The gene discussed is APOE; the disease is colorectal carcinoma.