We have also observed some stem cell-like characteristics within the mix of different cell types and cell states present in spheroids, including Alcam, Aldh1, Gpx2, Ctnnb1, CD24, CD44, and CD166 warranting closer investigation of the tumorigenic compartment in this 3D culture model for tumor tissue as well as the use for in vitro drug testing. This evidence concerns the gene GPX2 and neoplasm.