The absence of CD8+ T cells in the
tumor center has become a major obstacle in the
immunotherapy of
colorectal cancer. Therefore, new therapeutic strategies are urgently needed to promote the accumulation of CD8+ T cells in the
tumor center. Previous studies have shown that
triterpenoid of Rhus chinensis (TER) is involved in the proliferation and apoptosis of
colorectal cancer cells, and can regulate their immune activity, but its mechanism needs to be further elucidated. In this study, the antitumor effect and adaptive immune response of TER on
tumor-bearing mice were evaluated and compared with
5-fluorouracil. The results showed that TER could significantly inhibit
tumor growth and prolong the survival time of
tumor-bearing mice. The In Vivo studies have shown that TER can not only enhance antitumor immunity and promote the accumulation of CD8 + T cells to
tumor sites, but also inhibit
tumor progression by regulating the expression of PD-1 and PD-L1 and significantly reducing the mortality of mice. Our study demonstrated for the first time that TER has oncolytic effect, and recruited adaptive immune cells to enhance the efficacy of anti-PD-1/PD-L1 in
colorectal cancer, which provides a potential therapeutic target for combined
immunotherapy of
colorectal cancer.