These enzymes bind chitin but do not have chitinolytic activity, are upregulated during inflammation or cancer, influence the inflammatory response using pathways such as interleukin (IL)-3 (IL-3)–mediated signaling and mitogen-activated protein kinase (MAPK) signaling, and appear to be involved in cell proliferation, cell survival, and angiogenesis.45 The gene discussed is IL3; the disease is cancer.