Abstract PO005: Obesity-associated Visfatin, and Silibinin in an In Vitro and In Vivo Model of Liver Cancer

Abstract

Abstract Introduction: Obesity, specifically body fatness, is a risk factor for the development of liver cancer. The link between obesity and liver cancer is likely to be mediated in part by a state of chronic inflammation. However, it has yet to be determined if visfatin inhibition, a pro-inflammatory adipocytokine upregulated by obesity, is sufficient to prevent or delay the progression of liver cancer. Obesity-induced inflammatory factors may promote cancer progression by increasing cell proliferation, motility, invasion, and metastasis.The use of dietary compounds may break the pro-inflammatory cycle induced by the obese state, thus attenuating the cancer process. Silibinin, a polyphenol in milk thistle seed, has been shown to have anti-inflammatory properties. Studies have yet to determine whether silibinin can be used to break the obesity-cancer link to delay progression of liver cancer. The objective of this cell culture and mouse study is to determine the efficacy of silibinin in the prevention of obesity-associated liver cancer progression. Methods: SNU-449 and HepG2 liver cancer cells were exposed to the following experimental conditions; control, FBS, visfatin (80 ng/ml), visfatin + silibinin 40 μM, silibinin (40 μM). Cell proliferation, lipogenesis, lactate dehydrogenase secretion, and ROS production were measured. Immunoblot was used to measure phospho-Akt, phospho-Erk, NF-kB, Bcl-xL, and actin. Eight-week-old C57BL/6J male mice were randomized to a high-fat DIO (n=6) or control diet (n=6). At 14 weeks, mice will be injected subcutaneously with syngeneic Hepa1-6 murine liver cancer cells. At 15-weeks, mice will receive peritoneal injections of silibinin 3 times per week for 2 weeks. Tumors will be measured and assessed for visfatin, Akt, Erk, and NF-kB protein expression. Results from the animal study are on-going and will be presented at time of the conference. Results: SNU-449 and HepG2 cells exposed to visfatin significantly increased cell proliferation and lipogenesis when compared to control. Further, the addition of silibinin inhibited the visfatin-induced proliferation and lipogenesis in both cell lines. Visfatin increased the phosphorylation of Akt and Erk, and NF-kB expression in both liver cancer cell lines. The addition of silibinin differently suppressed phosphorylation of Akt and Erk in SNU-449 and HepG2 cells. Conclusion: Silibinin differentially inhibits visfatin-induced cell growth, lipogenesis, and promotes cytotoxicity which may lead to increased cancer cell death. Citation Format: Elisa Pedone, Kelly N Green, Kelly R Thornton, Ramona S. Price. Obesity-associated Visfatin, and Silibinin in an In Vitro and In Vivo Model of Liver Cancer [abstract]. In: Proceedings of the AACR Special Conference: Advances in the Pathogenesis and Molecular Therapies of Liver Cancer; 2022 May 5-8; Boston, MA. Philadelphia (PA): AACR; Clin Cancer Res 2022;28(17_Suppl):Abstract nr PO005.