Fig. 2

Genes of cholesterol pathway and related lipids are upregulated in the tamoxifen-resistant T-47D cell lines. a Hierarchical clustering and heat map visualization of each parental/resistant cell line pair and patient primary/metastatic tumor. Orange (negative log2-ratio) represents increase and blue (positive log2-ratio) decrease in expression in the resistant cell lines/metastatic tumor. Log2 ratios of > = |2| are displayed in the same color. b Filipin staining reveals an increase in intracellular amounts of free cholesterol in tamoxifen-resistant T-47D cells +/− 1 μM 4-OH- tamoxifen. c Quantification of lipid content in cells grown +/− 1 μM 4-OH-tamoxifen reveals an increase in cholesterol esters and triglycerides in tamoxifen-resistant cells (depicted as colored bars). Only significant differences (p-value < 0.05) between the same clone as well as of the comparison between resistant and tamoxifen-resistant cells in the same treatment conditions are indicated, all other comparisons can be found in Additional file 3. d LipidToxGreen staining of neutral lipids (green) demonstrates that accumulation of neutral lipids into lipid droplets in tamoxifen-resistant cells. The nuclei (blue) were stained with Hoechst