Inflammation is a physiological process that normally leads to recovery from injury by healing. However, if targeted destruction and assisted repair are not properly phased, inflammation can lead to persistent tissue damage by activated leukocytes, including reorganization of the extracellular matrix. Cytokines produced by the activated leukocytes trigger signal transduction cascades and positive feedback loops which will further lead to chronic/persistent effects. This chain of events is observed in several pathologies that are considered as acute or chronic 'inflammatory' diseases where one or several signal(s) or checkpoints in the control of the inflammatory process are deregulated. Importantly, an emerging link between chronic inflammation and cancer is being established and some cancers can also be considered as chronic inflammatory diseases. Mediators released by different cell types (neutrophils, macrophages, mast cells,...) control the proper phasing of the inflammation process by steering gene transcription in target cells.