To maintain the ease of culturing HCC derived hepatocytes and allow study of physiologically relevant hepatocyte metabolic activity, researchers developed a subline of HCC cell lines with enhanced expression of CYP3A4 mRNA and CYP3A4-mediated activity such as C3A subline 28 (C3Asub28) [25]. The gene discussed is CYP3A4; the disease is hepatocellular carcinoma.