RAET1E and sarcoma: In order to investigate the individual roles of NKG2D ligands in the response of GM NK-92 cells, we primarily determined mRNA level expression of ULBP1, ULBP2, ULBP3, ULBP4, and ULBP5 molecules in the sarcoma explants used in Figure 3 and complemented this data with MICA/B cell surface expression and NKG2D-Fc staining of each explant (Figure S2).