Huge true aneurysm of the facial artery treated with internal trapping and surgical excision: a case report.

A report of true aneurysms is extremely rare. There are only five previous case reports of true aneurysm of the facial artery. In the previously reported cases, there was no case that underwent trapping and surgical excision. In this case report, we describe the procedure of internal trapping before the surgical excision of a huge true aneurysm of the right facial artery for a 79-year-old woman. There was no recurrence of the aneurysm during a 6-month follow-up period.

Establishment and characterization of a human adenoid cystic carcinoma cell line forming colonies cultured in collagen gel and transplantable in nude mice.

We established a new cell line (ACCNS) from human adenoid cystic carcinoma (AdCC) of the maxilla, using tissue culture techniques and it has been successfully subcultured for more than 100 passages during 2 years. The population doubling time was approximately 39.2 h on a plastic dish. In type I collagen gel culture, the cells formed spherical colonies by day 7 after seeding. The colonies showed tubular and solid structures, and eosinophilic material stained with mucicarmine was revealed in the inner space. Immunohistochemically, ACCNS cells demonstrated expressions of keratin, alpha-smooth muscle actin, vimentin and S-100 protein, similar to those of original AdCC. These findings indicate that ACCNS cells possess the characteristics of AdCC. In addition, inoculation of 4.0x10(6) cells into nude mice developed tumors that were histologically confirmed as undifferentiated carcinoma. Therefore, ACCNS is the first AdCC cell line with tumorigenicity in nude mice. Based on these results, ACCNS provides a useful culture model of AdCC to analyze the biological characteristics and behavior of this tumor.

Role of stromal thrombospondin-1 in motility and proteolytic activity of oral squamous cell carcinoma cells.

The immunohistochemical localization of thrombospondin-1 (TSP-1) in human normal oral mucosa and oral squamous cell carcinoma (SCC) was examined. The immunostaining of TSP-1 was mainly localized in the connective tissues adjacent to the epithelium of oral mucosa, whereas epithelial cells showed negligible immunoreactivity for TSP-1. TSP-1 expression was striking in the stroma of SCC. TSP-1 synthesis by SCC cells and fibroblasts in culture was examined by immunoprecipitation with anti-TSP-1 antibody. Fibroblasts produced a large amount of TSP-1, whereas SCC cells secreted little amount of TSP-1. Treatment of fibroblasts by the conditioned medium of SCC cells led to an increase in TSP-1 synthesis. TSP-1 induced haptotactic migration and stimulated the production of matrix metalloproteinase-9 (MMP-9) in SCC cells. These results suggest that TSP-1 in the stroma of oral SCC might be synthesized by mesenchymal cells but not by epithelial cells, and that the synthesis of TSP-1 might be regulated by interaction with SCC cells. TSP-1 accumulated in the stroma might promote the progression of oral SCC by enhancing the motility and proteolytic activity in a paracrine manner.

Participation of fibroblasts in MMP-2 binding and activation on the surface of oral squamous cell carcinoma cells.

The effect of fibroblasts on the activation of matrix metalloproteinase-2 (MMP-2) in oral squamous cell carcinoma (SCC) cells was examined. The plasma membrane of SCC cells failed to bind and activate latent MMP-2. However, treatment of SCC cells with fibroblast-conditioned medium (fibroblast-CM) led to the enhancement of the binding and activation of latent MMP-2 on the cell surface. Moreover, fibroblasts induced the expression of membrane type 1 MMP (MT1-MMP) in SCC cells. MMP-2 activated on the cell surface bound to the surface of SCC cells via alphav integrins. These findings suggest that fibroblasts might facilitate the invasion of SCC cells by increasing the proteolytic activity on the surfaces of SCC cells.