In patients with oral cancer receiving neoadjuvant treatment with either PD-1 monotherapy or PD-1 therapy combined with cytotoxic T-lymphocyte associated protein 4 (CTLA-4) inhibitor, single-cell and T-cell receptor (TCR) sequencing revealed that both peripheral blood and tumor-infiltrating CD8+ T cells exhibited activation and amplification, featuring highly overlapping clone types (6). The gene discussed is PDCD1; the disease is neoplasm.