High-mobility group box 1 (HMGB1), a DAMP with pleiotropic functions, is involved in various intracellular (e.g., chromatin remodeling, transcription, autophagy) and extracellular (inflammation, autoimmunity) processes, which has been associated with both protumor and antitumor functions. Here, HMGB1 is linked to Autoimmunity.