CYP1A1 and hepatocellular carcinoma: Nevertheless, the current scientific literature suggests to us the presence of different scenarios: AFB1 can upregulate CYP1A1 gene expression, as shown in human hepatocytes [110] and a rat hepatoma cell line (5 μM AFB1, 0.5, 2, 4, 8, 16 h) [113]; but, at the same time, it may result in any transcriptional change [42].