PDPN expression was identified using the criteria described by Han et al.
Negative or focal PDPN immunoexpression (Figure 2) was more frequent in the CIN 3 group when compared with the CIN 1, CIN 2, and control groups: only 61.
Our data revealed that the groups did not necessarily present similar profiles when correlating VEGF and PDPN immunoexpression.
Transmembrane protein PDPN is expressed in endothelial cells of lymphatic vessels and it has been used as a lymphangiogenesis marker in solid tumors .
Our immunohistochemical analysis revealed that the frequency of diffuse PDPN expression was lower in CIN 3 (61% of samples) when compared to the other groups.
An association between low levels of PDPN in the tumor cells with the presence of lymphatic invasion and lymph node metastasis was found , suggesting that low expression of PDPN might be a risk marker of tumor recurrence and invasion of lymphatic system.
PDPN and VEGF immunoexpressions were simultaneously compared in the same fragments of low- and high-grade squamous intraepithelial lesions, but we did not find any statistical significance.
Due to lack of consistent results about these biological markers in cervical lesions, we noticed the importance to evaluate the profile of VEGF and PDPN immunoexpression and show their relevance as predictor for cancer progression, which have a great potential to prevent metastasis development.
Negative or focal PDPN expression was apparently more frequent in CIN 3 than in the other groups.
Caption: FIGURE 2: Microphotographs showing the immunohistochemical expression of PDPN in cervical tissues.