Figure 2.

Representative images of immunohistochemical staining. A: Negative expression of HIF-1α protein (× 200). B: Positive expression of HIF-1α protein (× 200). C: HIF-1α protein localized in the cytoplasm (× 400). D: HIF-1α protein localized in the nucleus (arrows) (× 400). E: Negative staining in fibroblasts and endothelial cells (arrows) (× 400). F: Positive staining in lymphocytes (arrows) (× 400).