Chiu DK et al. reported that MDSCs preferentially infiltrate into hypoxic regions of human hepatocellular carcinoma tissue, and hypoxia-induced MDSC infiltration is dependent on hypoxia-inducible factors, hypoxia-inducible factor activates the transcription of CCL26 in cancer cells, which recruits MDSC expressing the chemokine CX3CR1 to primary tumors, significantly increasing angiogenesis and promoting tumor growth (Chiu et al., 2016). Here, CX3CR1 is linked to cancer.