Screen Of Serum Biomarker For Rectal Carcinoma Using SELDI-TOF Mass Spectrometry

Objective To screen out serum biomarkers for rectal carcinoma in patient blood serum using the Surface Enhanced Laser Desorption/Ionization-time of flight- mass spectrometry (SELDI-TOF-MS) technique and bioinformatics.Methods 98 serum samples from rectal carcinoma patients and 40 ones from age- and sexmatched control group individuals,were analyzed by WCX-2 proteinchips under defined binding and washing conditions,and were subject to the ProteinChip reader,PBSII-C.Protein peak clustering and classification analysis were performed utilizing the Biomarker Wizard and Biomarker Pattern software packages,respectively.Results The results showed that 26 peaks had significant difference between rectal carcinoma patients and control group,twelve of which were up-regulated in the patient samples,and the others were down-regulated.Four protein peaks,9295 Da 3700 Da 3938 Da and 4095 Da were automatically chosen for the system training and the development of a classification tree.We divided all patients by using this classification tree.The result shows that two patients were missed in the 98 samples,two were mistaken for tumor in the 40 samples,and the corresponding sensitivity was 97.96%and the corresponding specificity was 95%.Tested by masked samples, this proteomic pattern has a higher sensitivity(95.0%,57/60) and specificity(93.4%,45/48);CEA has 68.3%(41/60) and 77.1%(37/48);CA199 has 58.3%(35/60) and 75%(36/48).Conclusion The study suggest that by using the technology of SELDI-TOF-MS and bioinformatics,specific biomarkers for rectal carcinoma can be screened from serum,and early diagnosis of rectal carcinoma can benefit from the research,which has higher sensitivity and specificity than the traditional tumor markers.