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

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.