ABCB4 and hepatocellular carcinoma: While the preferential uptake of ICG by the tumor cells is regulated by the cell membrane-binding ability of ICG, OATP1B3 and multi-drug resistance p-glycoprotein-3, as the main ICG-related transporters, play a pivotal role in the uptake of ICG in HCC; the former is an influx transporter, and the latter is an efflux transporter.