ESR1 and cancer: In samples of well- and moderately differentiated cancers there was a well-defined epithelial layer surrounding gland-like structures (G) which had intense immunostaining for ERβ5 (green nuclei, Fig. 2A, B and C), but within the stroma there were cells that appeared to express ERα (red) alone (fibroblast-like shape) (Fig. 2A, B and C).