New multi protein patterns differentiate liver fibrosis stages and hepatocellular carcinoma in chronic hepatitis C serum samples

AIM： To identify a multi serum protein pattern as well as single protein markers using surface-enhanced laser desorption/ionisation time-of-flight mass spectrometry （SELDI-TOF-MS） for detection and differentiation of liver fibrosis （F1-F2）, liver cirrhosis （F4） and hepatocellular carcinoma （HCC） in patients with chronic hepatitis C virus （HCV）. METHODS： Serum samples of 39 patients with F1/F2 fibrosis, 44 patients with F4 fibrosis, 34 patients with HCC were applied to CM10 arrays and analyzed using the SELDI-TOF ProteinChip System （PBS-Ⅱc; Ciphergen Biosystems） after anion-exchange fractionation. All patients had chronic hepatitis C and histologically confirmed fibrosis stage/HCC. Data were analyzed for protein patterns by multivariate statistical techniques and artificial neural networks. RESULTS： A 4 peptide/protein multimarker panel （7486, 12843, 44293 and 53598 Da） correctly identified HCCs with a sensitivity of 100% and specificity of 85% in a two way-comparison of HCV-cirrhosis versus HCV-HCC training samples （AUROC 0.943）. Sensitivity and specificity for identification of HCC were 68% and 80% for random test samples. Cirrhotic patients could be discriminated against patients with F1 or F2 fibrosis using a 5 peptide/protein multimarker pattern （2873, 6646, 7775, 10525 and 67867 Da） with a specificity of 100% and a sensitivity of 85% in training samples （AUROC 0.976） and a sensitivity and specificity of 80% and 67% for random test samples. Combination of the biomarker classifiers with APR/score and alfa-fetopotein （AFP） improved the diagnostic performance. The 6646 Da marker protein for liver fibrosis was identified as apolipoprotein C-I. CONCLUSION： SELDI-TOF-MS technology combined with protein pattern analysis seems a valuable approach for the identification of liver cirrhosis and hepatocellular carcinoma in patients with chronic hepatitis C. Host probably a combination of different serum markers will help to identify liver cirrhosis and early-stage hepatocellular carcinomas in the future.