RT Journal Article SR Electronic T1 Necrotic debris and STING exert therapeutically relevant effects on tumor cholesterol homeostasis JF Life Science Alliance JO Life Sci. Alliance FD Life Science Alliance LLC SP e202101256 DO 10.26508/lsa.202101256 VO 5 IS 3 A1 Sampath Katakam A1 Santosh Anand A1 Patricia Martin A1 Nicolo Riggi A1 Ivan Stamenkovic YR 2022 UL https://www.life-science-alliance.org/content/5/3/e202101256.abstract AB Malignant tumors commonly display necrosis, which invariably triggers an inflammatory response that supports tumor growth. However, the effect on tumor cells of necrotic debris, or damage-associated molecular patterns (DAMPs) released by dying cells is unknown. Here, we addressed the effect of DAMPs on primary Ewing sarcoma (EwS) cells and cell lines grown in 3D (spheroids) and 2D culture. We show that DAMPs promote the growth of EwS spheroids but not 2D cultures and that the underlying mechanism implicates an increase in cholesterol load in spheroids. In contrast, stimulation of the nucleic acid sensor signaling platform STING by its ligand cyclic GMP-AMP decreases the tumor cell cholesterol load and reduces their tumor initiating ability. Overexpression of STING or stimulation with cyclic GMP-AMP opposes the growth stimulatory effect of DAMPs and synergizes with the cholesterol synthesis inhibitor simvastatin to inhibit tumor growth. Our observations show that modulation of cholesterol homeostasis is a major effect of necrotic cell debris and STING and suggest that combining STING agonists with statins may help control tumor growth.