Hypoxia reduces the output of matrix metalloproteinase-9 (MMP-9) in monocytes by inhibiting its secretion and elevating membranal association

Cellular hypoxia, characterizing tumors, ischemia, and inflammation induce recruitment of monocytes/macrophages, immobilize them at the hypoxic site, and alter their function. To migrate across the extracellular matrix and as part of their inflammatory functions, monocytes and macrophages secrete proteases, including matrix metalloproteinase‐9 (MMP‐9), whose expression is induced by proinflammatory cytokines [e.g., tumor necrosis factor α (TNF‐α)]. We show that hypoxia (