HepG2 is a human cell line isolated from a liver biopsy of a 14-year-old male donor. HepG2 cells are used in a wide range of studies, from the oncogenesis to the cytotoxicity of substances in the liver. HepG2 cells have been used to study liver function broadly, including liver metabolism, cancer metastasis, and tumor formation. These cells secrete various major plasma proteins, including albumin, α2-macroglobulin, α1-anti-trypsin, and plasminogen. These cells can be used for (i) the study of carcinogenesis as a surrogate for liver toxicity, (ii) the analysis of signaling events, (iii) molecular biology, and (iv) protein-based assays. These immortalized hepatic cell lines can be used instead of biopsies for research purposes. These HepG2 cells are homogenous and grow robustly in cell culture. HepG2 cells grow slowly initially and grow in clusters rather than as an intact monolayer. Vial contains approximately 500,000 cells. Shipped with dry ice.