Linear ubiquitination-induced necrotic tumor remodeling elicits immune evasion.

Abstract

Tumor-elicited inflammation confers tumorigenic properties, including cell death resistance, proliferation, or immune evasion. To focus on inflammatory signaling in tumors, we investigated linear ubiquitination, which enhances the nuclear factor-κB signaling pathway and prevents extrinsic programmed cell death under inflammatory environments. Here, we showed that linear ubiquitination was augmented especially in tumor cells around a necrotic core. Linear ubiquitination allowed melanomas to tolerate the hostile tumor microenvironment and to extend a necrosis-containing morphology. Loss of linear ubiquitination resulted in few necrotic lesions and growth regression, further leading to repression of innate anti-PD-1 therapy resistance signatures in melanoma as well as activation of interferon responses and antigen presentation that promote immune-mediated tumor eradication. Collectively, linear ubiquitination promotes tumor-specific tissue remodeling and the ensuing immune evasion.