TNFRSF11B and neoplasm: Mice receiving cells of 67NR tumor–bearing donors that had been transduced with OPG-targeting shRNA (B 67NR sh OPG) exhibited tumor progression comparable with that of the 4T1 group, whereas those receiving B 67NR or 67NR tumor–bearing donors that had been transduced with a scrambled control (B 67NR sh scr) maintained reduced tumor burden throughout the observation period (Fig. 5D and E).