Natural Killer Cells Suppress T Cell-Associated Tumor Immune Evasion

Abstract

Summary: Despite the clinical success of cancer immunotherapies, the majority of patients fail to respond or develop resistance through disruption of pathways that promote neo-antigen presentation on MHC I molecules. Here, we conducted a series of unbiased, genome-wide CRISPR/Cas9 screens to identify genes that limit natural killer (NK) cell anti-tumor activity. We identified that genes associated with antigen presentation and/or interferon-γ (IFN-γ) signaling protect tumor cells from NK cell killing. Indeed, Jak1-deficient melanoma cells were sensitized to NK cell killing through attenuated NK cell-derived IFN-γ-driven transcriptional events that regulate MHC I expression. Importantly, tumor cells that became resistant to T cell killing through enrichment of MHC I-deficient clones were highly sensitive to NK cell killing. Taken together, we reveal the genes targeted by tumor cells to drive checkpoint blockade resistance but simultaneously increase their vulnerability to NK cells, unveiling NK cell-based immunotherapies as a strategy to antagonize tumor immune escape. : Freeman et al. use a series of genome-wide loss-of-function genetic screens to identify genes that limit tumor sensitivity to killing by natural killer cells. The findings highlight that natural killer cells can suppress tumor immune evasion from T cells, identifying a potential strategy to overcome resistance to checkpoint blockade therapy. Keywords: natural killer cell, CRISPR screening, tumor immune evasion, immunotherapy