KIR2DL4 and melanoma: Recent study has found a novel comprehensive index of aging and immune (CIAI) signature comprising 7 genes, including KIR2DL4, in which patients with melanoma in the high-CIAI group exhibited significantly shorter overall survival (OS), disease-specific survival (DSS), and progression-free interval (PFI), suggesting that the CIAI model can serve as an independent prognostic index.