Fig. 4From: Osteoblasts are “educated” by crosstalk with metastatic breast cancer cells in the bone tumor microenvironmentUnique protein expression occurs with EO cell presence in the hematopoietic niche of tumor-bearing bones. 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. The tibia sections from athymic mice were prepared as described in the “Materials and methods” section. The 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. The bone marrow microenvironment was examined via fluorescent microscopy. As shown on the tibia at the left, the black box represents the positioning of the tumor in the examples shown, whereas the red triangle represents the locations in the bone where the images were taken. At least three independent, serial sections were stained per bone and three bones examined per condition. Shown are representative images. Scale bar = 50 μmBack to article page