(A) Osteoclastogenesis assays of primary bone marrow cultured together with DLC1 KD or control cells treated with TGF-β, or in CM from SCP28 cells treated with TGF-β, C3, and/or Y27632 (n = 3). (B) Osteoclastogenesis assays of primary bone marrow culture in SCP2 CM (n = 3). Representative TRAP staining images are also shown. Arrows denote TRAP-positive osteoclasts. (C) Osteoclastogenesis assays of CM from additional MDA231 derivative cell lines (n = 3). Green and red text denotes cell lines with high and low DLC1 expression, respectively. (D) Osteoclastogenesis assays of CM from cancer cells treated with various genes or chemical reagents (n = 3). (E) TRAP staining of bone metastasis tumors from animals injected with DLC1 KD or OE cancer cells. (F) Osteoclast cells along the tumor-bone interface (n = 3). Scale bars: 100 μm. *P < 0.05, **P < 0.01.