ABSTRACT
<p><b>OBJECTIVE</b>To study the oncogene transcriptor c-myc, stimulatory protein 1 (SP1) expression in ameloblastoma (AB) and their relation with telomerase reverse transcripase (hTERT), and to investigate the clinical biological characteristics of AB.</p><p><b>METHODS</b>The expression was observed in AB by in situ hybridization and SP method.</p><p><b>RESULTS</b>The positive rates of c-myc mRNA, hTERT mRNA and SP1 protein were 81.5% (44/54), 94.4% (51/54) and 83.3% (45/54), respectively. Their positive rates increased as AB recurred and transformed malignantly. A strong correlation was found between hTERT and c-myc, hTERT and SP1 (rs = 0.853, P < 0.001; rs = 0.900, P < 0.001).</p><p><b>CONCLUSION</b>Activity of telomerase plays an important role in the tumorigenesis development of AB. Increasing of hTERT expression may be related to c-myc and SP1. The expression of these three parameters has a significant correlation with the clinical biological characteristics of AB.</p>
Subject(s)
Humans , Ameloblastoma , Metabolism , Proto-Oncogene Proteins c-myc , Metabolism , Sp1 Transcription Factor , Metabolism , Telomerase , MetabolismABSTRACT
<p><b>OBJECTIVE</b>To investigate the invasive biologic behavior of ameloblastoma (AB) and to analyze its correlative factors.</p><p><b>METHODS</b>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).</p><p><b>RESULTS</b>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).</p><p><b>CONCLUSION</b>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.</p>
Subject(s)
Adolescent , Adult , Aged , Child , Female , Humans , Male , Middle Aged , Ameloblastoma , Chemistry , Pathology , Cadherins , Jaw Neoplasms , Chemistry , Pathology , Matrix Metalloproteinase 2 , Matrix Metalloproteinase 9 , Neoplasm Invasiveness , Vascular Endothelial Growth Factor AABSTRACT
<p><b>OBJECTIVE</b>To investigate the expression of pRb and E2F-1, and the association between their expression and the activity of telomerase (hTERT) or cyclin E in human ameloblastoma (AB), and to explore the clinical biological characteristics of AB.</p><p><b>METHODS</b>The expressions of pRb, E2F-1, cyclin E and hTERT mRNA in human AB were detected by in situ hybridization or immunohistochemistry (SP method).</p><p><b>RESULTS</b>The positive expression ratio of pRb in the cell nucleus of AB was 20.4% (11/54). The positive ratio of E2F-1, cyclin E and hTERT mRNA was 92.6% (50/54), 66.7% (36/54) and 94.4% (51/54), respectively. With AB recurrence and malignant transformation, the expression of hTERT, E2F-1, cyclin E was up-regulated. hTERT and cyclin E or E2F-1 mRNA had high positive relation (Spearsman'r(s) = 1.000, P = 0.0001).</p><p><b>CONCLUSIONS</b>The regulatory pathway of Rb/E2F-1 is associated with the cell proliferation and in differentiation of AB. The activity or release of telomerase may be related to the lower expression of Rb and higher expression of E2F-1, and is up-regulated in G(1) late phase by cyclin E.</p>