XKR8 and neoplasm: Interestingly, however, E0771 Xkr8 knockout cells did not show apparent defects in tumor cell proliferation (Fig.2.D.) or tumorsphere formation in Matrigel as shown by tumorsphere size (Fig.2.E.) and tumorsphere count (Fig.2.F.), or defects in the immediate Gas6-maediated activation of Akt (SFig 2B) suggesting the Xkr8 does not impinge on the cell intrinsic oncogenic features of these cells in cell culture.