Although the biology of LAG-3 has not been as widely studied as that of PD-1, our data provide practical evidence for the pleiotropic roles of LAG-3 in reinvigorating exhausted T cells and intriguing anti-tumour responses, and it, therefore, constitutes a new promising immunotherapeutic target for EBV (+) GC. This evidence concerns the gene PDCD1 and gastric cancer.