Effect of 10,12-CLA dose on mammary gland expression of genes regulating ductal growth. Female FVB mice received 10,12-CLA at doses of 0, 0.1, 0.2, or 0.5% of the diet from day 24 to 49 of age (n = 8 to 10 per treatment). The left abdominal mammary gland was collected at 49 days of age. Total RNA was analyzed by real-time PCR for the mRNA abundance of indicated genes. A: estrogen receptor (ERα) and amphiregulin (ARG). B: IGF-I and IGF binding protein 5 (IGFBP5). C: chemokine monocyte chemoattractant protein-1 (MCP-1) and the macrophage marker EGF-like module containing mucin-like hormone receptor-like sequence 1 (EMR1), TNF-α, and IL-6. D: receptor of activated NF-κB (RANK) and RANK ligand (RANKL). Data were normalized to 18S expression except for genes expressed predominantly in the epithelium (ARG, RANK, and RANKL). Each bar represents the mean ± SE of 8 mice. a,bBars with different letters are significantly different, P < 0.05.