Representative m-aconitase immunohistochemistry of human prostate tissue sections. Left panel. A. Negative control. B. Field that shows adjacent BPH and malignant foci. C. Field showing adjacent PIN and malignant glands. Right panel. A-D are H&E staining; a-d are immunohistochemical staining. Note strong brown positive staining of glandular epithelium in all cases; and contrasting less staining of stroma.