HCC serum associated proteins screened by SELDI-TOF-MS analysis / 中华检验医学杂志

ABSTRACT

Objective To screen potential serum HCC associated proteins with low molecular weight and low abundance for better understanding the pathological mechanism of HCC and discovering new biomarkers.Methods All serum samples were collected from 81 HBV-related HCC patients,43 chronic hepatitis B patients and 36 cirrhosis patients.Serum protein fingerprint profiles were first generated by selected WCX2 protein chip integrating with SELDI-TOF-MS,and then normalized and aligned by Ciphergen SELDI Software 3.1.1 with Biomarker Wizard.Comparative analysis of the intensity of corresponding protein fingerprint peaks in normalized protein spectra was performed.Some protein peaks with significant difference among HCC,cirrhosis and chronic hepatitis B groups were found.The reproducibility of the SELDI system was assessed before serum protein fingerprint profiles analysis.Results The intra-and inter-assay CV for intensity and m/z in this SELDI system were 17.46% and 0.024%,and 17.74% and 0.024% respectively.Total 128 protein fingerprint peaks between 2 000 to 30 000 Da were identified under the condition of signal to noise＞5 and minimum threshold for cluster＞20%.Eighty-seven proteins were found to significantly expressed between HCC and cirrhosis groups(P＜0.05).Of the above differential proteins,forty-five proteins had changes greater than two fold,including 15 up-regulated proteins and 30 downregulated proteins in HCC sera.Between HCC and chronic hepatitis B groups,nine of fifty-two differential proteins(P＜0.05) had intensities of more than two folds,including 2 up-regulated proteins and 7 downregulated proteins in HCC sera.Between cirrhosis and chronic hepatitis B groups,twenty-eight of seventynine significantly differential proteins(P＜0.05) changed greater than two folds in intensity,including 17 up-regulated proteins in cirrhosis seru and 11 down-regulated proteins in chronic hepatitis B sera.Analysis of above leading differential proteins among three diseases using subtraction difference mode,the 5 common down-regulated proteins 2 870,3 941,2 688,3 165 and 5 483 m/z in HCC sera and 2 common up-regulated proteins 3 588 and 2 017 m/z in cirrhosis and HCC sera were screened.But no statistic difference in the level of protein 2 017m/z was found between HCC group and normal group inour previous study.Conclusion Because the interference of unspecific proteins from hepatitis B and cirrhosis could be eliminated partly in HCC sera through subtraction difference analysis,these 6 common differential proteins (2 870,3 941,2 688,3 165,5 483,3 588 m/z)have obvious advantages of increased specificity for evaluating the pathological state of HCC and might become promising candidate biomarkers in the diagnosis of HCC.