Background: Potentially malignant oral disorders (PMODs) are common precursors of oral squamous cell carcinoma (OSCC). Neoangiogenesis and signalling are important intermediate biomarkers that may govern the progression of dysplastic mucosa into carcinoma. Aims: Evaluate the importance of CD34 and Wnt3 expression in PMODs and OSCCs in relation to their clinicopathological parameters. Settings and Design: Prospective cross-sectional study. Materials and Methods: Immunohistochemical staining for CD34 and Wnt3 was performed for 41 samples. These included 27 PMODs, six OSCCs and eight normal gingival and alveolar mucosa. Analysis of variance (ANOVA) and post-hoc tests were applied. P<0.05 was considered statistically significant. Results: CD34 expression showed a significant difference between groups (P<0.05). CD34 expression decreased in patients who had PMODs, and it was seen to correlate with clinical staging in OSCC patients. The alveolar epithelia had lower microvessel density (MVD) (9.3±.88) than the gingiva (17.47±5.09) (P<0.05), whereas the lichen planus without dysplasia had lower MVD (8.85±3.95) than both the gingiva and the dysplastic epithelia (14.46±3.89) (P<0.05). On the other hand, Wnt3 expression was not detected in the alveolar mucosa, but scattered perinuclear and nuclear expression in the gingival mucosa was observed. Cytoplasmic Wnt3 expression was seen in all oral lichen planus (OLP) and some leukoplakia cases with no nuclear staining, whereas its expression in proliferative verrucous leukoplakia was only nuclear. Furthermore, OSCCs showed both cytoplasmic and nuclear expression. Conclusion: MVD may represent a useful biomarker preceding oral cancer development. It increases from normal mucosa to dysplasia to carcinoma. Aberrant cytoplasmic expression of Wnt3 is detected in PMODs and OSCCs. Thus, Wnt3 may be involved in disease progression.
