Foundation Of Serum Protein Fingerprint Filing And Application In Early Diangnosis Of Colorectal Cancer

AIM Study the changes of proteomic spectra in serum from patients with colorectal cancer in order to detect the specific protein markers. METHODS 146 cases of the patients with colorectal cancer,62 cases of the healthy people and 32 cases of patients with the benign colorectal diseases were tested by Proteinchip PBSâ…¡3.1 System of ciphergen Inc.ln second stage.proteomic spectra of sixty-four serum samples from patients with colorectal cancer (preoperation and postoperation) and forty from normal individuals were generated by IMAC-Cu proteinchip array and SELDI-TOF mass spectroscopy(surface enhanced laser desorption ionization-time of flight). The discriminatory profiling between cancer and normal samples was analyzed by Biomarker Wizard software and Biomarker Pattern software. RESULTS At the M/Zvalues range from 4467Da to 15122Da, there were ten protein contents of the three groups are obviously different. Analysis of the spectra from every the 146 cases of the patient and 62 cases of the control and 32 cases of the benign colorectal diseases, correctly calssified 142 of 146(97.26%) of colorectal cancer patients; 62 of 62(100%) of healthy people as healthy people and 32 of 32(100%) of the benign colorectal diseases patients as benign colorectal diseases, corresponding correct ratio was 98.33%.we screened for nineteen differentially expressed proteins in serum by analysis of protemic spectra of preoperative patients and normal individuals. And we obtained five proteins(5972.67Da , 5927.21 Da , 6113.48Da, 5908.55Da and 4292.51 Da) making up markers pattern which was able to class the patient-team and normal-team. Corresponding correct ratio were 97.5% (56/64) and 80% (32/40) The proteins that overexprssed in serum of preoperative patients had obviously down-regulated. CONCLUSION The preliminary results suggest that clssification system will provide a highly accurate and innovative approach for the early diagnosis of colorectal cancer and judgment of prognosis. SELDI-TOF mass spectrometry is a useful tool for the detection and idenification of new protein markers in serum.