SUMMARY
Purpose: Studies on odontogenic tumors have identified various molecular dysfunctions involved on their development, and some mechanisms such as angiogenesis and matrix modulation, are useful means of investigating the differences in biologic behavior of these tumors. Some important markers to identify tumor aggressiveness by immunohistochemistry are VEGF, TGF-ß and MMP-9 proteins. This study aimed to compare the immunohistochemical expression of VEGF, TGF-ß, and MMP-9 in ameloblastoma and adenomatoid odontogenic tumor (AOT).Methods: Immunoexpression of VEGF, TGF-ß, and MMP-9 was studied in 15 solid ameloblastomas, and 15 AOTs. A semi-quantitative analysis of the immunostained cells was performed, and the statistical analysis was made using the Mann-Whitney nonparametric and Spearman correlation test, with significance level at .05 (P<.05).Results: A higher epithelial immunoexpression of VEGF and TGF-ß was observed in ameloblastoma and AOT, respectively, and the stromal reactivity to VEGF was statistically higher in ameloblastoma (P<.05). No statistical difference was observed for MMP-9 (P>.05).Conclusion: The results suggest the involvement of angiogenesis in tumor progression of ameloblastomas, and the inductive effect of stromal cells in AOT, hence justifying its lower growth potential.