Fig. 6

Immunohistochemical evaluation of methylation markers. a 5-methylcytosine (5-mC) and b 5-hydroxymethylcytosine (5-hmC) levels were determined in FFPE sections from letrozole-treated samples. Representative images in dormant and resistant tumours are shown. Boxplots show distributions of semi-quantitative intensity scores of 5-mC (*p < 0.05, ***p < 0.001; n = 5–12) and 5-hmC (***p < 0.001; n = 5–13) levels in dormant and resistant tumours. Early-on (early, 13–120 days) and long-term (long, > 120 days) neoadjuvant aromatase inhibitor therapy with letrozole