This cluster is characterized by the expression of cytolytic effector genes, including FGFBP2, FCGR3A, CX3CR1, GZMB, GZMH, and PRF1. Moreover, these cytotoxic ILC1s are mainly enriched in non-tumor tissues, while in tumor samples ILC1s are characterized by higher levels of exhaustion markers, such as LAG3, thus suggesting that ILC1s could undergo functional conversion during liver cancer progression. This evidence concerns the gene PRF1 and neoplasm.