REL and neoplasm: In addition, to evaluate whether knocking down TNFR1 alone, or its combination with RelA, RelB, or c‐Rel, as well as knocking down CUL4B + RelA, would result in the same suppressive effects in vivo, we injected nude mice with U2OS‐control‐shRNA, U2OS‐TNFR1‐KD, U2OS‐TNFR1‐KD + RelA‐KD, U2OS‐TNFR1‐KD + RelB‐KD, U2OS‐TNFR1‐KD + c‐Rel‐KD, U2OS‐CUL4B‐KD, U2OS‐CUL4B‐KD + RelA‐KD, and U2OS‐SPD304 cells and monitored tumorigenesis for 30 days by measuring tumor volumes at 5‐day intervals.