Budget Amount *help |
¥2,100,000 (Direct Cost: ¥2,100,000)
Fiscal Year 1993: ¥400,000 (Direct Cost: ¥400,000)
Fiscal Year 1992: ¥1,700,000 (Direct Cost: ¥1,700,000)
|
Research Abstract |
Meningiomas are generally benign. However, they recur with a rate of 10-30%, even after total resection, and there are biologically aggressiove meningiomas. To study the cell biology of human meningioma, we isolated a new immortal cell line with the ability to form vimentin-filament anchoring desmosome, a differentiation marker of arachnoid cell, from metastatic meningioma-derived cells (GMM-2). We obtained more than 30 clones from the GMM-2 cells, but most of the clones became senescent. We selected a clone designated HMG-10 for further study, which achived 100 population doubling level. In the log phase, HMG-10 cells formed epthelioid cell (E) sheets. After confuluence, part of them poorly spread, and appeared to bie fibroblastoid cells (F).13EA02 : Immunocytochemistry revealed that desmoplakin-positive dots were aligned at cell-to-cell boudaries. Cytoplasmic dots were considered intternalized desmosomes. Vimentin-positive filamants were distributed around the nucleus. Actin filaments were present mainly at the cell periphery. None of the cells were positive for cytokeratin, epithelial membrane antigen and E-cadherin. Electron microscopy of HMG-10 cells showed desmosomes and numerous cytoplasmic IF.IF anchoring desmosomes were assembled not only between E cells, but also between E cell and F cell as well as between F cells. In growth medium containing 10% fetal calf serum, the cells grew exponentially with a doubling time of about 47 hours after the first medium change. Their growth was contact-inhibited at a low density of 20,000 cells/cm^2. We are hopeful that further studies on the expression of cell adhesion molecules of HMG-10 cells will provide some insights into the growth control mechanism of human meningioma cells.
|