Publications by authors named "Yu Nakao"

Ameloblastoma is an epithelial benign tumor of the odontogenic apparatus and its growth mechanisms are not well understood. Fibroblast growth factor (FGF) 3, FGF7 and FGF10, which are expressed by the neural crest-derived ectomesenchymal cells, induce the proliferation of odontogenic epithelial cells during tooth development. Therefore, we examined the expression and function of these FGFs in ameloblastoma.

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Sonic hedgehog (SHH) signaling pathway is crucial to growth and patterning during organogenesis. Aberrant activation of the SHH signaling pathway can result in tumor formation. We examined the expression of SHH signaling molecules and investigated the involvement of the SHH pathway in the proliferation of ameloblastoma, the most common benign tumor of the jaws.

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Tumor necrosis factor alpha (TNFalpha) can trigger both cell survival and apoptosis. In the present study, from the flow cytometry results, we found that the prolonged-treatment of TNFalpha until 24 h, resulted apoptosis in AM-1 cells (ameloblastoma cell line). These results were confirmed by DAPI staining, which showed nuclear fragmentation feature of AM-1 cells under treatment of TNFalpha.

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Tumor-necrosis-factor-related apoptosis-inducing ligand (TRAIL/Apo-2L), a potent ligand in inducing apoptosis, has recently emerged as a novel anticancer agent based on its ability to induce apoptosis in tumor cells, while exhibiting no toxicity in most normal cells. Since no potent apoptosis-inducing factor has been found yet in ameloblastoma, the present study was conducted. In the present study, expressions of TRAIL receptors, death receptor 4 (DR4) and DR5, were detected in all ameloblastoma tissues by immunohistochemistry as well as in AM-1 cells by immunofluorescence.

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Purpose: We describe a method for symmetrical vermilion reconstruction after resection of hemangiomas of the lip.

Patients And Methods: Four patients underwent vermilion reconstruction after resection of large cavernous hemangiomas of the lip. This reconstruction technique employed 3 basic components: 1 ) labial mucosal advancement flap, 2 ) orbicularis oris muscle flap, if necessary, and 3 ) free mucosal graft.

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Ameloblastoma, a tumor located in bone, when neglected, can perforate the bone and, ultimately, spread into the soft tissues. To expand in the bone, ameloblastoma must have a mechanism of resorbing the surrounding bone. However, the mechanism for bone resorption is poorly understood.

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Tumour necrosis factor alpha (TNFalpha) is known crucial in inducing cell survival, proliferation, differentiation, and apoptosis. In the present study, we found that TNFalpha as well as its receptors, TNFR1 (TNF Receptor 1) and TNFR2, were clearly expressed in ameloblastoma tissues and AM-1 cells. By stimulation of TNFalpha in AM-1 cells, the phosphorylation of Akt (Ser473) and p44/42 mitogen-activated protein kinase (MAPK) (Thr202/Tyr204) was markedly increased in TNFalpha concentration and time dependent manner.

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