Abstract

Although neoadjuvant chemotherapy (NAC) has shown efficacy in reducing tumor burden in colorectal cancer (CRC), its impact on long-term patient outcomes remains limited. Here, we identify quiescent persister tumor cells (PTCs) as a critical determinant of therapeutic failure. Elevated PTC abundance correlates with poor long-term prognosis, even in patients exhibiting an initial response to treatment. Quiescent PTCs possess aggressive stem-like traits and orchestrate an immunosuppressive microenvironment characterized by CD96 + CD8 + T cell infiltration in an orthotopic CRC mouse model. CD96 depletion diverts CD8 + T cells from an exhaustion trajectory and promotes memory-like phenotypes through enhanced mitochondrial function. Consistently, anti-CD96 therapy effectively eliminates PTCs in preclinical models. We also engineered epithelial cell adhesion molecule (EpCAM)-targeted human chimeric antigen receptor (CAR)-T cells deficient in CD96 expression, which robustly target PTCs and demonstrate remarkable therapeutic potential against CRC. Overall, our study uncovers CD96 as a previously unrecognized axis of vulnerability within the PTC-driven microenvironment, offering a promising avenue to enhance CRC therapeutic outcomes.