Fig. 4.

Heterogeneity of cell types in human breast. a Double immunostaining of normal human breast section with keratin 5 (red) and smooth muscle actin (SMA, green, FFPE, 400×). b Triple immunostaining of normal human breast section with keratin 5 (blue), estrogen receptor (red), and androgen receptor (green). The cells that co-express ER and AR are yellow (FFPE, 400×). c Triple immunostaining of normal human breast section with keratin 5 (red), keratin 18 (green) and CD10 (white). The cells that co-express K5 and K18 are yellow (FFPE, 400×). d Double-immunostaining of normal human breast section with AR (green) and vitamin-D receptor (red). The cells that co-express AR and VDR are yellow (FFPE, 400×)