Mitochondrial checkpoint for interferon responses in macrophages.

A functional immune system is a key antagonist of cancer cell growth. Cytokines such as interferons (IFNs) promote the onset of inflammation, turn cells into an anti-viral state, and shape the dynamic tumor-immune cell interactome. Recent work illustrates how type I IFNs contribute to the resolution of inflammatory conditions. This involves macrophage-mediated efferocytosis for the clearance of apoptotic cells and the intrinsic capacity of type I IFNs to restrict their own autocrine signaling loops via the IFN-stimulated gene 15 (ISG15) protein. We discuss how this may affect tumor cells and how acetylation-dependent processes can affect the phosphorylation-dependent signaling cascades that augment IFN-dependent gene expression.