According to the theory of the cancer-immunity cycle, tumor-draining lymph nodes (tdLNs) provide crucial places for dendritic cells and other antigen-presenting cells to activate naïve CD8+ T cells and therefore differentiate into progenitor and precursor exhausted T cells, which are the ancestors of tumor-specific T cells that finally infiltrate into the tumor (4, 5). The gene discussed is CD8A; the disease is neoplasm.