Background: Women have a lower risk of hepatocellular carcinoma (HCC) than men, and the decreased possibility of HCC in women is thought to depend on estrogen levels. As a soybean-isoflavone product, genistein has estrogenic activity in various reproductive tissues, because it mimics 17β-estradiol and binds the estrogen receptor. Though genistein is a known liver cancer suppressor, its effects have not been studies in long-term experiment, where genistein is fed to a female animal model of HCC.
Methods: Mice were treated with diethylnitrosamine (DEN) to induce HCC at 2 weeks of age and fed with supplemental genistein for 5 months, from 40 to 62 weeks of age.
Results: The dietary intake of genistein decreased the incidence of HCC and suppressed HCC development. Genistein induced phospho-AMPK in total liver extracts, Hep3B cells, and Raw 264.7 cells, and phospho-AMPK promoted apoptosis in liver and Hep3B cells. Moreover, phospho-AMPK down-regulated pro-inflammatory responses and ameliorated liver damage. A suppressed pro-inflammatory response with increased mitochondrial respiration was concomitantly observed after genistein treatment.
Conclusions: Genistein-mediated AMPK activation increases hepatocyte apoptosis through energy-dependent caspase pathways, suppresses the inflammatory response in resident liver macrophages by increased cellular respiration, and consequently inhibits the initiation and progression of HCC.
Keywords: AMPK; Apoptosis; Genistein; HCC; Inflammation; Phytoestrogen.