Figure 3.

Androgen receptor expression in benign, high-grade prostatic intraepithelial neoplasia, and cancerous lesions of the prostate and its association with Gleason’s grade

(A) AR expression was analyzed by immunohistochemistry in BPH (n = 35), HGPIN (n = 38), and PCa (n = 105). Representative images exhibiting nuclear AR staining (red arrow) were captured at 20X magnification (Scale bar: 200 μm; left panels) and digitally enhanced (2X) for improved visualization (right panels) are shown.

(B) Digital analysis of scanned slides for nuclear AR expression by Aperio ImageScope shows a greater distribution of strongly positive cells in HGPIN and PCa lesions than in BPH.

(C) AR expression is significantly higher in PCa as compared to the BPH and HGPIN in median H score comparison. No significant differences in AR expression between HGPIN and BPH are observed. The data are presented as boxplots showing highest and lowest H score. Kruskal-Wallis test was performed for comparing the differences between groups and a p value of <0.05 was considered statistically significant.

(D and E) A higher percentage of cells in high Gleason (n = 51) grade PCa stained strongly positive compared to low-medium grade (n = 54) PCa leading to significant differences in overall AR expression. The data are presented as a boxplot depicting median (horizontal line) value of each group. Top and bottom edges of the box represent 75th percentile (third quartile) and 25th percentile (first quartile), and whiskers point highest and lowest H scores. The differences between the groups were calculated by Mann Whitney U test and a p value of <0.05 was considered significant.

(F) Representative images showing a stronger nuclear AR immunostaining in high-grade (Gleason score 9) PCa relative to low-grade (Gleason score 7) PCa were captured at 20X magnification (Scale bar: 200 μm; left panels) and digitally enhanced (2X) for improved visualization (right panels) are presented. Nuclear AR staining is depicted by red arrows. GS: Gleason score.