PRF1 and neoplasm: Kraya and colleagues found that cytolytic activity, defined as the mean expression of PRF1 and GZMA, was higher in patients with a BRCA-mutated tumor (48 BRCA1-mutated, 41 BRCA2-mutated) compared to patients with an HR-proficient tumor (n = 652), with no difference between BRCA1-mutated tumors and BRCA2-mutated tumors [23].