STAT3 and cancer: When DCs come into contact with cancer cells, they send a “don’t eat me” signal through the classic ITIM–SHP1 complex that mediates anti-phagocytic effects but also through SIRPα, which detects cancer mitochondrial DNA for cross-priming or activate the STAT3 signaling pathway to suppress the production of cytokines (such as IL-12, TNF-α, and interferon-γ) and consequently inhibit DC maturation.