JAK1 and neoplasm: Antibody-mediated neutralization of IFN-γ in the co-culture medium significantly alleviated cytotoxicity in the WT and GOF tumor organoids, but had no effect in JAK1 LOF cells (Figures S7F and S7G), consistent with a high level of IFN-γ release from autologous anti-tumor T cells upon exposure to tumor cells,63 which was modestly increased with nivolumab (Figure S7H).