Cytotoxic T cells co-cultured with MDSCs sorted from midkine-overexpressing HCC tumors showed reduced Ki67 and Granzyme B expression compared with T cells co-cultured with MDSCs derived from EV-transduced tumors, indicating that the proliferation and activation of T cells were repressed (Fig. 4E, F). The gene discussed is MDK; the disease is hepatocellular carcinoma.