Extracellular S100A8/A9 heterodimer (25–250 μg/ml) formed by the two calcium-binding proteins S100A8 and S100A9 exerts apoptosis-inducing activity in various cells via suppression of intracellular zinc or interaction with receptor, but in lower doses (<25 μg/ml), either their heterodimer or each alone promotes the viability or migration of tumor cells, vascular endothelial cells and inflammatory cells, which is involved in the binding with receptor for advanced glycation end products (RAGE) through mitogen-activated protein kinase (MAPK) pathway and NF-κB activation [15]–[24]. Here, S100A9 is linked to neoplasm.