ECM1 and neoplasm: Interestingly, among the 12 genes comprising the validated GEP clinical prognostic test11, five are expressed predominantly in tumor cells as expected (EIF1B, HTR2B, ECM1, CDH1, and ROBO1), but one is expressed predominantly in T cells (SATB1), and the remaining six are expressed in both tumor and immune cells (Supplementary Fig. 3 and Supplementary Data 1).