Sesamolin enhances NK cell lysis activity by increasing the expression of NKG2D ligands on Burkitt's lymphoma cells

• We demonstrate the anti-cancer activity of sesamolin on Raji cells.
• NKG2D ligands play key role in the NK cell mediated lysis of cancer cells.
• Sesamolin increases the susceptibility of Raji on NK cell mediated cytolysis.
• NKG2D ligand expressions increase on Raji following incubation with sesamolin.
• The sensitivity of sesamolin-treated Raji to NK cell lysis is due to ERK signal.

Sesamolin and sesamin are representative lignans found in sesame seed. The present study was designed to demonstrate the anti-cancer activity of sesamolin achieved by increasing the expression level of NKG2D ligands on Raji cells, which are derived from Burkitt's lymphoma. The anti-cancer activity of sesamolin was also compared with that of sesamin. The cytolysis activity of NK cells against Raji was elevated by the pretreatment of sesamolin on Raji, but not by sesamin. We found that higher NKG2D ligand expression increased the sensitivity of sesamolin-treated Raji to NK cell lysis, resulting from a more active ERK signaling pathway. Our results provide evidence that targeting the ERK signaling pathway may enhance the antitumor activity of lignans and that there is a potential immunotherapeutic value for cancer treatment.