The idea that CD8+ T cells contribute to tumor growth in this model is counterintuitive because: (i) DEN-treated RAG-deficient mice develop liver tumor nodules earlier than WT mice, at 6 months of age, supporting the importance of adaptive immunity in preventing early tumor development (141) and (ii) high CD8+ T cell infiltration is a hallmark of so-called “hot” tumors, correlating with a greater antitumor response in various cancer types and with better responses to immunotherapy (142). The gene discussed is CD8A; the disease is cancer.