The hydrogel matrix is derived from basement membrane extracts of Engelbreth–Holm–Swarn mouse sarcoma and contains major cellular matrix (ECM) components including laminins, collagen IV, heparan sulfate proteoglycans as well as growth factors (TGFβ, epidermal growth factor (EGF), insulin-like growth factor (IGF) and fibroblast growth factor (FGF) [46,47,48,49]. The gene discussed is IGF1; the disease is sarcoma.