Kitao A, Matsui O, Yoneda N, et al. - This study was intended to evaluate the utility and safety of gadoxetic acid-enhanced MR imaging for hepatocellular carcinoma. In hepatocellular carcinoma (HCC), the expression of organic anion transporting polypeptide (OATP) 1B3 correlates with the increase ratio in the hepatobiliary phase. It was demonstrated that OATP1B3 expression and the less aggressive nature of hyperintense HCC are regulated by the molecular interaction of β-catenin signaling and hepatocyte nuclear factor 4α, a tumor suppressor factor. It was noted that HCC indicating hyperintensity on the hepatobiliary phase is a peculiar genetic subtype of HCC with OATP1B3 overexpression, a less aggressive nature, and mature hepatocyte-like molecular/genetic features. Gadoxetic acid-enhanced MR imaging has the potential to be an imaging biomarker for HCC.