IL6 and neoplasm: Restoring IL‐6 expression to control levels (e.g., added 3.3 ng to bring to 4 ng/ml) rescued osteoclast differentiation induced by MDA.A2KD tumor cells, and a neutralizing anti‐human IL‐6 antibody significantly inhibited osteoclast differentiation induced by MDA.V cells in indirect (Supplementary Information Fig. S4B; p < 0.05) and direct (Supplementary Information Fig. S4C; p < 0.05) coculture assays.