Figure 1: Representative examples of immunohistochemical staining patterns of HIF-1α, NFκB and P-selectin. A: Normal tissue counterpart shows absence of staining (magnification x 200). B: moderate cytoplasmic HIF-1α staining in a well differentiated tumour (magnification x 400). Very few cells exhibit nuclear staining (arrows). C: Moderate cytoplasmic NFκB staining in a differentiated tumour (magnification x 400). One cell shows nucleus staining (arrow). D: Endothelial cells of the tumour associated blood vessels stained for P-selectin are observed in a poorly differentiated tumour (magnification x 400). Haematoxylin counterstained.