[Correlations of extrocellular matrix metalloproteinase inducer and microvessel density to invasiveness of ameloblastoma].

BACKGROUND & OBJECTIVE: Matrix metalloproteinases (MMPs) are involved in local invasion of ameloblastomas. This study was to evaluate the role of matrix metalloproteinase inducer (EMMPRIN) in angiogenesis in ameloblastomas by analyzing EMMPRIN expression and microvessel density (MVD) in ameloblastomas and odontogenic cysts. METHODS: EMMPRIN expression and MVD in 41 specimens of ameloblastoma and 40 specimens of odontogenic cyst were examined by SP immuno-histochemistry. RESULTS: EMMPRIN was detected in all specimens of ameloblastomas and odontogenic cysts. The strong positive rate of EMMPRIN was significantly higher in ameloblastomas than in odontogenic cysts (85.4% vs. 62.5%, P<0.05). MDV was positively correlated to EMMPRIN expression to some extent (r=0.677, P<0.01). CONCLUSION: EMMPRIN may play an important role during the progression of ameloblastoma via controlling angiogenesis and degradation of extracellular MMPs.

Cellular toxic effects of combination of low dose of cisplatin and interstitial injection of 32P glass microspheres on mouse solid tumor S180.

BACKGROUND: Although 32P-glass microspheres (32P-GMS) have been used in internal radiotherapy for malignant tumors, it has been one of the key obstacles to improve the effect of radiotherapy. We investigated the cellular and hypersensitive effect of combined use of low dose of cisplatin and interstitial injection of 32P-GMS on mouse solid tumor S180. METHODS: The mice with solid tumor S180 were randomly divided into four groups (controls, cisplatin therapy, 32P-GMS therapy and combination therapy). The specimens of the mice were sectioned two weeks after treatment and weighed. The death rate of tumor cells and the inhibition rate of tumor were calculated respectively. The cell cycle and apoptosis rate were evaluated with flow-cytometry. The ultrastructural changes of the four groups were observed by a transmission electron microscope. The data were analyzed by the chi-square test. RESULTS: The growth of tumor was slower in the combination therapy group than in the simple therapy groups by macrography. The inhibition rate and the death rate of tumor cells of the combination therapy group were significantly higher than those of the control group and the other two simple therapy groups (P < 0.05). More cell damages were displayed in the combination therapy group than in the other groups under the light and electronic microscope. CONCLUSION: Low-dose cisplatin combined with interstitial injection of 32P glass microspheres could be used as an effective hypersensitive regimen for the internal radiotherapy of mouse solid tumor S180.