Table 1.
Expression of proteins in the cortical and trabecular bone, bone marrow, and tumor of mice inoculated via intratibial injection. Athymic nude mice were injected via intratibial injection with an admix of MDA-MB-231GFP/Luc2 human breast cancer cells plus either EO-231 cells or MC3T3-E1 osteoblasts, or MDA-MB-231GFP/Luc2 cells alone. Eight weeks later, mice were euthanized and their tibia harvested. Sections were stained for osteopontin, alkaline phosphatase, VEGF, alpha-smooth muscle actin, MMP3, collagen type I, MCP-1, IL-6, and green fluorescent protein via immunofluorescence. At least three independent sections were stained per bone, and three bones examined per condition. Protein expression is listed as a percentage of the total population of cells as quantified using Count and Measure per fluorophore in cellSens (Olympus)
| Cell type injected | Bone turnover | Neovascularization | Inflammatory cytokines | Extracellular matrix remodeling | ||||
|---|---|---|---|---|---|---|---|---|
| ALP (%) | OPN (%) | aSMA (%) | VEGF (%) | IL-6 (%) | MCP-1 (%) | Col-1 (%) | MMP3 (%) | |
| Cortical and trabecular bone (endosteal niche) | ||||||||
| EO + 231 | 29 | 47 | 71 | 33 | 2 | 1 | 55 | 44 (away from BC) |
| OB + 231 | 0 | 80 | 63 | 25 | 55 | 16 | 64 | 41 (away from BC) |
| 231 alone | 0 | 39 | 50 | 0 | 37 | 0 | 55 | 17 (close to BC) |
| Bone marrow (hematopoietic niche) | ||||||||
| EO + 231 | 15 | 45 | 54 | 23 | 27 | 35 | 0 | 12 |
| OB + 231 | 27 | 0 | 57 | 41 | 40 | 39 | 0 | 25 |
| 231 alone | 13.5 | 17 | 42 | 0 | 27 | 32 | 37 | 33 |
| Tumor itself | ||||||||
| EO + 231 | 0 | 35 | 28 | 29 | 17 | 0 | 24 | 17 |
| OB + 231 | 0 | 0 | 15 | 13 | 0 | 5 | 24 | 5 |
| 231 alone | 12 | 15 | 19 | 17 | 0 | 31 | 23.5 | 33 |