Detecting biomarkers from serum in colorectal cancer patients with SELDI-TOF-MS protein chip

Objective: To detect biomarkers from serum with SELDI-TOF-MS to early diagnoses colorectal cancer and its lymph node mestastatic. Methods: 60 cases of serum from colorectal cancer patients, 28 cases from health people, 26 cases from colorectal cancer patients with no mestastatic lymph node, 34 cases with mestastatic lymph node, were combined with the surface of H4 and IMAC3 (Immobilized Metal Affinity Capture) protein chip, then tested with SELDI-TOF-MS and analyzed by Biomarker Wizard software and Biomarker Pattern software to get a diagnosis standard after the albumin were discarded by cibacron blue. And the standards were reconfirmed by a Double-blindly analysis to 20 cases of serum from colorectal cancer patients, 20 cases from health people, 19 cases from colorectal cancer patients with no mestastatic lymph node, 24 cases with mestastatic lymph node. Results: At the key m/z values of 8 176, 5 943, 6 886, 11 442, 3 345, protein contents in serum between health and colorectal cancer patient have a remarkably different. Analysis of the spectra from both 20 cases of the patient and 20 cases of the control, correctly classified 20 of 20 (100 %) of the health as not cancer and 20 of 20 (100 %) of the patient as cancer, This result yielded 100 % sensitivity and 100 % specificity. At the key m/z values of 2872. 19 3, protein contents in serum are obviously different between patients with with no mestastatic lymph node and patients with mestastatic lymph node. A Double-blind analysis to 19 cases from colorectal cancer patients with no mestastatic lymph node, 24 cases with mestastatic lymph node showed that the positive predictive value of this standard is 70.83% (17/24)and the negative predictive value 68.42 % (13/19). Conclusions: Biomarkers detected from serum of colorectal cancer patients with H4 and IMAC3 (Immobilized Metal Affinity Capture) protein chip and the SELDI-TOF-MS technology, can be regarded as a new, more sensitive, more specific method to diagnose colorectal cancer and its lymph node mestastic.