While Ad5H2E-PPE1(3x)-ASMase treatment had no significant effect on baseline tumor growth (P>0.1; not shown), it conferred local tumor cure in 3 of 12 animals (25%) following 34 Gy SDRT (Fig. 6C, left panel) and 5 out of 6 animals after 41 Gy (83%; Fig. 6C, right panel). This evidence concerns the gene SMPD1 and neoplasm.