This possible explanation is supported by the findings of Cao et al.[34] who reported that elevated arginase-1 staining is associated with chronic HCV infection as they found that arginase-1 expression was elevated in more than 75% of HCV infected liver samples compared to paired HCC from the same patients (> 33% positive) and to uninfected liver tissues (0% positive). The gene discussed is ARG1; the disease is hepatocellular carcinoma.