PRF1 and neoplasm: The percentage of CD8, IFN-γ, Granzyme B and Perforin were 12.0, 6.4, 19.8 and 6.9% in tumor tissues respectively, compared to 19.9, 16.7, 44.1 and 16% in adjacent normal tissues (n = 17) (Fig. 1c, d and Additional file 1: Figure S1A, B).