Charaterization of the three dimensional cultured ameloblastoma cells

Objectives: Ameloblastoma is believed to be originated from the odontogenic epithelium, thus the ameloblastoma cells might characterize the ameloblasts and the tumor cells as well. The purpose of this study is to investigate the secretion of the extracellular matrix of enamel (amelogenin and MMP20) and the expression of the cell cycle-related factors in 3-D cultured ameloblastoma cells compared to the ameloblasts. Methods: The specimen from a multicystic ameloblatoma and tooth germ were chopped and digested with 2%Collagen-dispase at 37°C for one hour. The cell suspension was planted on the 90mm plates(Primeria,Becton Dickson,NJ) and cultured in KGM (Clontenics,Biowhittaker,UK, with 0.05Mm Ca2+)media with serum. 2nd passage cells were planted on 1ml Matrigel(Becton Dickinson)in 96-well plate with the concentration of 4x 104 /cm2.The media were changed every other day. 2 w later the cells were fixed in 10% formalin for 1h and dehydrated and embedded. The slices were made with 4µm. The slices were immunostained with anti- amelogenin and anti-MMP20 antibodies and anti-Bcl-2(Santa Cruze,CA,USA)Aanti-Rb(Santa Cruze,CA,USA)and anti-P16(Santa Cruze,CA,USA). Results: The results showed that the ameloblastoma cells and ameloblasts growed clusters in the 3-D matrigel. The two kinds of cells were stained positive to AMELOGENIN(1F1000),MMP20(1F1500),Rb(1F50) and P16(1F50). The Bcl-2 staining was positive in the ameloblastoma cells but negative in ameloblasts. Conclusions: It is concluded that both ameloblasts and ameloblastoma cells can secret the extracellular matrix of enamel which represented the similarity of their origins.The ameloblastoma cells charaterized as tumors via expressing Bcl-2. The continuing expression of Bcl-2 in the 3-D cultural matrice suggested that such in vitro system is helpful in the furthur study on the ameloblastoma.The expression of the cell cycle-related factors demonstrated that the growth and division of these cells were control by the factors.