N-MYC impairs innate immune signaling in high-grade serous ovarian carcinoma

High-grade serous ovarian cancer (HGSC) is a challenging disease, especially for patients with immunologically “cold” tumors devoid of tumor-infiltrating lymphocytes (TILs). We found that HGSC exhibits among the highest levels of MYCNexpression and transcriptional signature across human cancers, which is strongly linked to diminished features of antitumor immunity. N-MYC repressed basal and induced IFN type I signaling in HGSC cell lines, leading to decreased chemokine expression and T cell chemoattraction. N-MYC inhibited the induction of IFN type I by suppressing tumor cell–intrinsic STING signaling via reduced STING oligomerization, and by blunting RIG-I–like receptor signaling through inhibition of MAVS aggregation and localization in the mitochondria. Single-cell RNA sequencing of human clinical HGSC samples revealed a strong negative association between cancer cell–intrinsic MYCN transcriptional program and type I IFN signaling. Thus, N-MYC inhibits tumor cell–intrinsic innate immune signaling in HGSC, making it a compelling target for immunotherapy of cold tumors.