OBJECTIVE: To investigate the invasive biologic behavior of ameloblastoma (AB) and to analyze its correlative factors. METHODS: The specimens of 43 cases of AB (primary AB 16 cases, recurrent AB 21 cases, malignant AB 6 cases) were examined immunohistochemically using the streptavidin-biotin method to determine the expression of E-cadherin (E-cad), matrix metalloproteinase (MMP)-2, MMP-9 and vascular endothelial growth factor (VEGF). RESULTS: The cells in malignant AB scattered more, grew invasively, and the basal membrane ruptured or lost. The expression of E-cad in AB descended, MMP-2 and MMP-9 were strongly expressed in the epithelia cells of 28/41, 30/43 cases of AB, respectively. The positive rate and intensity of VEGF increased as AB recurred and transformed malignantly. The expression of E-cad, MMP-9 and VEGF were related to recurrence or malignant transformation of AB (r(s) = 0.309, 0.519, 0.381, P < 0.05). CONCLUSION: AB is a high invasive tumor. The biological behavior of AB is related to lost or abnormal expression of E-cad, the high expression of MMP-2, MMP-9, and VEGF.
OBJECTIVE: To investigate the invasive biologic behavior of ameloblastoma (AB) and to analyze its correlative factors. METHODS: The specimens of 43 cases of AB (primary AB 16 cases, recurrent AB 21 cases, malignant AB 6 cases) were examined immunohistochemically using the streptavidin-biotin method to determine the expression of E-cadherin (E-cad), matrix metalloproteinase (MMP)-2, MMP-9 and vascular endothelial growth factor (VEGF). RESULTS: The cells in malignant AB scattered more, grew invasively, and the basal membrane ruptured or lost. The expression of E-cad in AB descended, MMP-2 and MMP-9 were strongly expressed in the epithelia cells of 28/41, 30/43 cases of AB, respectively. The positive rate and intensity of VEGF increased as AB recurred and transformed malignantly. The expression of E-cad, MMP-9 and VEGF were related to recurrence or malignant transformation of AB (r(s) = 0.309, 0.519, 0.381, P < 0.05). CONCLUSION: AB is a high invasive tumor. The biological behavior of AB is related to lost or abnormal expression of E-cad, the high expression of MMP-2, MMP-9, and VEGF.