GPNMB and hepatocellular carcinoma: In human hepatic carcinoma tissue and in the malignant hepatic cell line HepG2, ARSB activity was reduced compared to normal control, and the expression of Glycoprotein Nonmetastatic Melanoma Protein B (GPNMB) was increased in hepatic tissue of ARSB null mice and ARSB silenced hepatic cells [14].