Considering the non-cytotoxic concentrations (300 μg/mL) of RGE on hPD-L1 MC38 and hPD-1 CD8+ T cells, a co-culture cell system was established using tumor-infiltrating CD8+ T cell as effector cells in conjunction with hPD-L1 MC38 cells as target cells to elucidate the CD8+ T cell-mediated antitumor effect of RGE. This evidence concerns the gene CD8A and neoplasm.