Extracellular high mobility group box-1 (HMGB-1), a prototypical molecule of damage-associated molecular patterns, activates NF-κB in endometriotic cells by binding to its receptor, Toll-like receptor 4 (TLR4), and induces inflammatory responses in the environment of endometriosis with sustained oxidative stress 52, 53. Here, TLR4 is linked to endometriosis.