HMMR inhibition by 4-methylumbelliferone is effective in preclinical hepatocellular carcinoma models

The poor prognosis of hepatocellular carcinoma (HCC), especially in advanced stages, underscores the need for new therapeutic strategies. In this study, we show that hyaluronan-mediated motility receptor (HMMR) is highly expressed in HCC tumors compared with normal liver tissues. Knockdown of HMMR using siRNA significantly reduced cell proliferation and migration in both parental and doxorubicin-resistant HCC cell lines without inducing apoptosis. Similarly, treatment with 4-Methylumbelliferone (4-MU), a pharmacological HMMR inhibitor, led to dose-dependent decreases in proliferation and migration in vitro. In vivo, 4-MU treatment significantly inhibited tumor growth in a HepG2 xenograft model, resulting in a 44% reduction in tumor volume by day 20 and an 80% decrease in HMMR expression in tumor tissues. These results demonstrate that HMMR promotes growth and migration in HCC, and targeting HMMR effectively inhibits both parental and drug-resistant HCC cells. Additionally, our findings suggest that 4-MU, an approved drug for biliary tract disorders, holds promise as a repurposed therapeutic candidate for HCC treatment.