c-Met is a novel tumor associated antigen for T-cell based immunotherapy against NK/T cell lymphoma

Background: The expression of c-Met and its ligand HGF plays a critical role in cell proliferation and is involved in numerous malignancies. Because c-Met expression and its role in NK/T-cell lymphoma remain unclear, we studied the expression and function of c-Met in NK/T-cell lymphoma cells. In addition, we investigated the possibility that c-Met could function as a tumor-associated antigen for helper T lymphocytes (HTLs).Methods: We evaluated whether HGF and c-Met were expressed in NK/T-cell lymphoma and the capacity of predicted c-Met HTL epitopes to induce antitumor responses in vitro. In addition, c-Met inhibitor was evaluated for the ability to inhibit TGF-β production in tumor and subsequently increase HTL recognition.Results: c-Met and HGF were expressed in NK/T-cell lymphoma cell lines, nasal NK/T-cell lymphoma specimens and patient serum samples. Moreover, HGF was shown to promote NK/T cell lymphoma (NKTCL) proliferation in an autocrine manner. Furthermore, we have identified three novel c-Met H...