Published online Nov 28, 2016. doi: 10.3748/wjg.v22.i44.9744
Peer-review started: May 30, 2016
First decision: August 8, 2016
Revised: September 9, 2016
Accepted: October 10, 2016
Article in press: October 10, 2016
Published online: November 28, 2016
Processing time: 181 Days and 21.4 Hours
To evaluate the efficacy of peripheral blood concentrations of angiopoietins (Ang) as cirrhosis biomarkers of chronic hepatitis C (CHC).
Ang1 and Ang2 serum levels were measured by enzyme-linked immunosorbent assays (ELISA) in samples from 179 cirrhotic and non-cirrhotic CHC patients, classified according to the METAVIR system. Groups were compared by non-parametric Mann-Whitney U test. Subsequently, the association of peripheral concentrations of angiopoietins with the stage of fibrosis was analyzed using Spearman correlation test. Finally, the accuracy, sensitivity and specificity of circulating angiopoietins for cirrhosis diagnosis were determined by the study of the respective area under the curve of receiver operator characteristics (AUC-ROC).
Peripheral blood concentrations of Ang1 and Ang2 in CHC patients were significantly related to fibrosis. While Ang1 was decreased in cirrhotic subjects compared to non-cirrhotic (P < 0.0001), Ang2 was significantly increased as CHC progressed to the end stage of liver disease (P < 0.0001). Consequently, Ang2/Ang1 ratio was notably amplified and significantly correlated with fibrosis (P < 0.0001). Interestingly, the individual performance of each angiopoietin for the diagnosis of cirrhosis reached notable AUC-ROC values (above 0.7, both), but the Ang2/Ang1 ratio was much better (AUC-ROC = 0.810) and displayed outstanding values of sensitivity (71%), specificity (84%) and accuracy (82.1%) at the optimal cut-off (10.33). Furthermore, Ang2/Ang1 ratio improved the performance of many other previously described biomarkers or scores of liver cirrhosis in CHC.
Ang2/Ang1 ratio might constitute a useful tool for monitoring the progression of chronic liver disease towards cirrhosis and play an important role as therapeutic target.
Core tip: Chronic hepatitis C (CHC) is the leading cause of cirrhosis and hepatocellular carcinoma and monitoring of liver fibrosis is essential for the prognosis and treatment of these patients. Liver biopsy, the gold standard for fibrosis determination, is invasive and costly. Therefore, novel reliable non-invasive biomarkers are crucial for CHC management. Angiogenesis is closely related to the pathogenesis of the disease and angiopoietins play a relevant role in this process. Interestingly, this study confirms the valuable association of circulating angiopoitein-1 (Ang1) and angiopoitein-2 (Ang2) levels with CHC progression and reveals the outstanding role of Ang2/Ang1 ratio as potential non-invasive biomarker of cirrhosis.