IL6 and breast cancer: Combined, reductions in cancer cell CM-educated osteoblasts were seen in the expression of IL-6 and alpha-SMA, whereas increases in educated osteoblast protein expression were observed with collagen type I. While differentiated osteoblast treatment with human mammary epithelial cell CM did elicit some alterations in osteoblast protein expression, these changes were minimal in comparison with alterations observed with treatment of breast cancer cell variant CM.