EGF and sarcoma: Briefly, the isolated Lgr5+ ISCs are embedded in Matrigel (a gelatinous protein mixture secreted by mouse sarcoma cells), with culture medium containing small molecules and growth factors (Wnt agonist R-spondin1, the bone morphogenetic protein (BMP) antagonist Noggin, and epidermal growth factor (EGF), Wnt3a, gastrin, progstaglandin E2, nicotinamide, the TGF-β receptor inhibitor A83-01 and p38 inhibitor SB202190) required for proliferation, differentiation and self-organize into a 3D organoid (Nanthakumar et al., 2000).