Figure 2. Resveratrol treatment induces HER2 over-expression and ERα down-regulation in HER2+/ERα+ mammary carcinomas. (a) Representative western blot analysis of ERα and β-actin (loading control) in spontaneous mammary tumors from Δ16HER2 mice supplemented or not with resveratrol (left panel), and relative densitometry quantification from three independent experiments (right panel). The significance was determined by unpaired two-tailed student t test, *p < 0.05. (b) Representative western blot analysis of HER2 and β-actin (loading control) in spontaneous mammary tumors from Δ16HER2 mice, supplemented or not with resveratrol (left panel), and relative densitometry quantification from three independent experiments (right panel). The significance was determined by unpaired two-tailed student t test, *p < 0.05. (c) Left panel: representative immunofluorescence images of tumor sections from control and resveratrol supplemented mice stained with an antibody anti-HER2 (green) and DRAQ5 dye (red) for nuclei staining. Magnification 400 X. Right panel: quantification of HER2 staining in tumors from resveratrol and vehicle treated mice. Data are expressed as mean ± SEM. *p < 0.05; unpaired two-tailed student t test. (d) Resveratrol treatment induces HER2 over-expression in lung metastases. Left panel: representative immunofluorescence images of lung metastasis sections from control and resveratrol supplemented mice stained with an antibody anti-HER2 (green) and DRAQ5 (red). Magnification 400 X. Right panel: quantification of HER2 staining in tumors from resveratrol and vehicle treated mice. Data are expressed as mean ± SEM. *p < 0.05; unpaired two-tailed student t test.