Treatment strategies and mechanisms associated with the prevention of NASH-associated HCC by a toll-like receptor 4 inhibitor.

We evaluated the cancer preventive efficacy of TAK-242, an inhibitor of toll-like receptor 4 (TLR4), in a mouse model of hepatocellular carcinoma (HCC) occurring in the context of non-alcoholic steatohepatitis (NASH). We also assessed the cellular events associated with the preventive treatment efficacy. We tested oral administration of TAK-242, at clinically-relevant but toxicity-reducing doses and scheduling, in mice with hepatocyte-specific deletion of Pten (HepPten-). The optimal dose and oral gavage formulation of TAK-242 were determined to be 30 mg/kg in 5% DMSO in 30% 2-hydroxypropyl-β-cyclodextrin. Daily oral administration of 30 mg/kg TAK-242 over 18 weeks was well-tolerated and resulted in reduced development of tumors (lesions >7.5 mm3) in HepPten- mice. This effect was accompanied by reduced macrovesicular steatosis and serum levels of alanine aminotransferase (ALT). In addition, 30 mg/kg TAK-242 daily treatment of small pre-existing adenomas (lesions <7.5 mm3) over 18 weeks, significantly reduced their progression to HCC. RNA sequencing identified 220 hepatic genes significantly altered upon TAK-242 treatment, that significantly correlated with tumor burden. Finally, cell deconvolution analysis revealed that TAK-242 treatment resulted in reduced hepatic populations of endothelial cells and myeloid-derived immune cells (Kupffer cells, Siglec-H high dendritic cells and NGP high neutrophils), while the proportion of MT-ND4 high hepatocytes significantly increased, suggesting a decrease in hepatic inflammation and concomitant increase in mitochondrial function and oxidative phosphorylation upon TLR4 inhibition. In conclusion, this study identified treatment strategies and novel molecular and cellular mechanisms associated with the prevention of HCC in the context of NASH that merit further investigations.