In this report, we demonstrate that α-TEA increased the frequencies of activated CD4+ and CD8+ T cells in the tumor microenvironment, induced a tumor-specific cytotoxic lymphocyte response and resulted in higher CD4+-to-Treg and CD8+-to-Treg ratios, as well as that the α-TEA-mediated antitumor effect was dependent on the T cell response. Here, CD4 is linked to neoplasm.