EGR2 O-GlcNAcylation orchestrates the development of protumoral macrophages to limit CD8+ T cell antitumor responses

Abstract

Tumor associated macrophages (TAMs) exhibit a high capacity to take up glucose. However, how metabolic cues derived from glucose rewire TAMs remains unclear. Here, we report that glucose metabolism-driven protein O-GlcNAcylation increases in TAMs and shapes the differentiation and protumoral function of TAMs. Deficiency of O-GlcNAc transferase (OGT) in TAMs restricted tumor growth by reducing the proportion of C1QC⁺ F4/80⁺ TREM2⁺ MerTK⁺ TAMs as well as Trem2 expression, which in turn preserved the cytotoxic function of effector CD8⁺ T cells while exhibiting reduced features of exhaustion. Mechanistically, O-GlcNAc targeted the macrophage-specific transcription factor EGR2 to promote its transcriptional activity. Transcriptional profiling revealed that OGT increased EGR2-related motifs accessibility in TAMs. O-GlcNAcylation of EGR2 at serine 299 enhanced its binding to myeloid cell differentiation-associated genes, including Trem2, thus facilitating the protumoral function of TAMs in GM-CSF-sufficient tumor. Overall, our work defines a tumor-specific reprogramming of protumoral TAMs via O-GlcNAc-modified EGR2 transcriptional regulation.

Keywords: CD8(+) T cells; EGR2; GM-CSF; TREM2; anti-tumor immunity; glucose metabolism; post-translational modification; protein O-GlcNAcylation; tumor associated macrophages; tumor microenvironment.