Silymarin Inhibits Proliferation and Induces Apoptosis in Epstein-Barr Virus-Positive Lymphoma Cells by Suppressing Nuclear Factor-Kappa B�Pathway

Abstract

Epstein Barr virus-positive lymphoma results from the loss of homeostatic balance between Epstein Barr virus and immune cells. In this study, we investigated the mechanism underlying reduction in Epstein Barr virus-positive lymphoma cell proliferation and apoptosis by silymarin, an anti-inflammatory/antioxidant molecule extracted from Silybum�marianum (milk thistle). We examined the effect of silymarin on Raji cell proliferation, apoptosis, the expression of latent membrane protein�1, the proteins related to apoptosis, and the activation of nuclear factor kappa-B. Results showed that silymarin inhibited the proliferation and promoted apoptosis of Raji cells in a concentration-dependent manner. Also, silymarin reduced phosphorylated inhibitor of nuclear factor kappa-B and p65 levels. Silymarin treatment elevated latent membrane protein 1 expression and knockdown of this protein led to increased proliferation inhibition and apoptosis by silymarin. In conclusion, nuclear factor kappa-B and latent membrane protein 1 knockdown could work in concert with silymarin in suppressing Epstein Barr virus-positive lymphoma cell proliferation and inducing apoptosis.