As shown in Fig. 1a and b, the CD8+ T cell and the functional markers IFN-γ, Granzyme B, and Perforin were lower in lung cancer tumor sites compared to adjacent normal tissues [CD8 P < 0.0001, IFN-γ P < 0.0001, Granzyme B P < 0.0001, Perforin P < 0.0001]. This evidence concerns the gene PRF1 and lung cancer.