Anticancer effect of propranolol on diethylnitrosamine-induced hepatocellular carcinoma rat model.

Background: Hepatocellular carcinoma (HCC) is the most widespread type of primary liver cancer. Diethylnitrosamine (DEN), a hepatotoxic hepatocarcinogenic compound, is used to induce HCC in animal models. The non-selective β-blocker propranolol demonstrated antiproliferative activity in many cancer types.

Objective: This investigation aimed to evaluate the anticancer effect of propranolol against DEN-induced HCC in rats.

Methods: Thirty adult male rats were divided into the following groups: Group I (C, control), Group II (HCC); received DEN, 70 mg/kg body weight (b.wt.) once a week for 10 weeks, to induce HCC, and Group III (HCC/Prop); received DEN for 10 weeks for HCC induction, then received 20 mg/kg b.wt. propranolol, intraperitoneally for four successive weeks.

Results: HCC was developed in rats' livers and confirmed via significant liver architecture changes, significantly elevated activity of alanine aminotransferase (ALT), aspartate aminotransferase (AST), α-fetoprotein (AFP), total- and direct-bilirubin (Bil), and a decline in albumin (ALB) level in serum. HCC group demonstrated elevated levels of malondialdehyde (MDA), nitric oxide (NO), HIF-1α, IL-8, NF-κB, PGE2, TGF-β1, VEGF, and CD8, but significant decline of GSH, and IL-10 level, with suppression of the antioxidant enzymes' activities. In addition, the gene expression of the hepatic inducible nitric oxide synthase (iNOS), and LAG-3 were up-regulated. Moreover, the protein expression of p-PKC was up-regulated, while that of PD-1 and PD-L1 were down-regulated in the liver tissues of the HCC group. However, propranolol ameliorated the investigated parameters in the HCC/Prop group.

Conclusion: Propranolol exhibited an anticancer effect and thus can be considered as a promising treatment for HCC. Blocking of PD-1/PD-L1 and LAG-3 signals participated in the anti-tumor effect of propranolol on HCC.