PDGF-immunohistochemistry. Expression of PDGFR-β in gastric cancer specimens: Intestinal type (a) gastric cancer expressed more commonly PDGFR-β, while diffuse type (b) often showed no expression. Note strong expression of PDGFR-β in the surface epithelium (b). Interestingly, PDGFR-β, was also found in myocytes of tumor blood vessel (c, d). Anti- PDGFR-β, hematoxylin counterstain; Original magnifications: x400 (a), x200 (b, d).