SPP1 and alcoholic liver diseases: This favors the hypothesis that OPN is a protein with multiple functions implicated in hepatic inflammation and fibrosis, and could be a relevant biomarker for significant liver fibrosis [19, 33], but in our cohort all patients have liver cirrhosis and we do not have assessed OPN levels from individuals with non-cirrhotic alcoholic liver disease or from healthy subjects, so we cannot conclude about its use as a biomarker of fibrosis.