CD248 and Ewing sarcoma: FACS analysis (Supplemental Figure 1) and immunofluorescence (Supplemental Figure 2) of the remaining nine sarcoma cell lines revealed that both SK-ES, a Ewing's sarcoma, and ST-88-14, a MPNST, displayed low to moderate TEM-1 expression, while the remainder of the panel were null expressers of TEM-1.