CD69 and neoplasm: Upon co-culture with Hepa1-6 cells, these T cells exhibited significantly higher expression of the early activation marker CD69 (Fig. 7D), secreted increased levels of IL-2 and IFN-γ (Fig. 7E), and showed enhanced proliferative capacity (Fig. 7F) compared to those from control mice, indicating the establishment of robust tumor-specific T cell immunity.