Following 72 hours of Wnt1 tumour fragment culture in ET-SIM cultures, IHC revealed low levels of cleaved caspase-3 (CC3) at both the free edge of the tumour as well as the edge in contact with the scaffold indicating that the tumour cells remain viable in ET-SIM cultures (Fig. 2a,iv,b,iv). Here, CASP3 is linked to neoplasm.