Chemotherapy-triggered cathepsin B release in myeloid-derived suppressor cells activates the Nlrp3 inflammasome and promotes tumor growth

Gemcitabine and 5-fluorouracil are two commonly used chemotherapeutic agents for the treatment of cancer. Francois Ghiringhelli and colleagues now report that the antitumor efficacy of these agents is mitigated by myeloid derived suppressor cells (MDSCs). The authors show that these drugs can activate the NLRP3 inflammasome, leading to increased secretion of IL-1β by MDSCs and IL-17 production by CD4+ T cells, which can promote tumor growth.