Peretinoin is an oral acyclic retinoid with a vitamin A-like structure that targets retinoid nuclear receptors such as retinoid X receptor (RXR) and retinoic acid receptor (RAR). Peretinoin reduces the mRNA level of sphingosine kinase 1 (SPHK1) in vitro by downregulating a transcription factor, Sp1. Peretinoin prevents the progression of non-alcoholic steatohepatitis (NASH) and the development of hepatocellular carcinoma (HCC) through activating the autophagy pathway by increased Atg16L1 expression. Peretinoin inhibits HCV RNA amplification and virus release by altering lipid metabolism with a EC50 of 9 μM.
Peretinoin is an active synthetic acyclic retinoid (ACR) whose in vivo anti-hepatocellular carcinoma (HCC) efficacy is attributed to its upregulatory activity toward retinoid nuclear receptors (RARbeta & RXRalpha), as well as negative regulation against sphingosine kinase 1 (SPHK1) expression and, thereby, sphingosine metabolic pathway. Peretinoin inhibits the replication of hepatitis B & C viruses in cultures (HBV & HCV EC50 = 9-25 μM) and shows in vivo efficacy in rodent models of hepatocarcinogenesis among rats (10, 40, or 80 mg/kg/day p.o.) and mice (0.03% or 0.06% in diet) subjected to chronic inflammation induction by diethylnitrosamine (DEN).