A transcriptomic study suggesting human iPSC-derived hepatocytes potentially offer a better in vitro model of hepatotoxicity than most hepatoma cell lines

Hepatocytes derived from human induced pluripotent stem cells (iPSCs) hold great promise as an in vitro liver model by virtue of their unlimited longterm supply, stability and consistency in functionality, and affordability of donor diversity. However, the suitability of iPSC-derived hepatocytes (iPSC-Heps) for toxicology studies has not been fully validated. In the current study, we characterized global gene expression profiles of iPSC-Heps in comparison to those of primary human hepatocytes (PHHs) and several human hepatoma cell lines (HepaRG, HuH-7, HepG2, and HepG2/C3A). Furthermore, genes associated with hepatotoxicity, drug-metabolizing enzymes, transporters, and nuclear receptors were extracted for more detailed comparisons. Our results showed that iPSC-Heps correlate more closely to PHHs than hepatoma cell lines, suggesting that iPSC-Heps had a relatively mature hepatic phenotype that more closely resembles that of adult hepatocytes. HepaRG was the sole exception but nonetheless suffers from lack of donor diversity and poor prediction of hepatotoxicity. The effects of sex differences and DMSO treatment on gene expression of the cellular models were also investigated. Overall, the results presented in the current study suggest that iPSC-Heps represent a reproducible source of human hepatocytes and a promising in vitro model for hepatotoxicity evaluation. Further studies are needed to develop a robust protocol for hepatocyte differentiation towards a more mature adult phenotype.