After confirming that Cgas overexpression boosted cGAMP secretion in liver cancer cells by detecting the levels of cGAMP in intracellular and extracellular media (Fig. 3d), we then tested whether cGAMP produced by liver cancer cells could activate STING in surrounding endothelial cells, using the formation of perinuclear STING aggregates as readout for STING activation by cGAMP10,18. This evidence concerns the gene STING1 and liver cancer.