We chose to use this 3-D model system since we have previously shown that concomitant treatment with TGF-β1 and EGF in this model enhanced growth to a greater extent than either growth factor alone [16], thereby recapitulating TGF-β‘s tumor promoting effects previously demonstrated in xenograft and orthotopic mouse models of PDAC [13]–[14]. This evidence concerns the gene EGF and neoplasm.