In accordance with this, Sceneay J et al. demonstrated that primary tumor hypoxia induces tumor cells to release CCL2, G-MCSF, TNFα, VEGF, TIMP-1 and MMP-9, which orchestrate the recruitment of MDSCs (CD11b+/Ly6Cmed/Ly6G+) in the pre-metastatic lung niche [138]. The gene discussed is MMP9; the disease is neoplasm.