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Dive into the research topics where Tokio Osaki is active.

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Featured researches published by Tokio Osaki.


Cancer Research | 2006

Tight Junction Protein Claudin-1 Enhances the Invasive Activity of Oral Squamous Cell Carcinoma Cells by Promoting Cleavage of Laminin-5 γ2 Chain via Matrix Metalloproteinase (MMP)-2 and Membrane-Type MMP-1

Naohisa Oku; Eri Sasabe; Eisaku Ueta; Tetsuya Yamamoto; Tokio Osaki

Although adherent junctions have been extensively studied, the role of tight junctions in cancer cell invasion is not sufficiently explored. We investigated whether claudin-1, a component of tight junctions, regulated invasion activity in oral squamous cell carcinoma (OSC) cells. The expression of claudin-1, activity of matrix metalloproteinase (MMP)-2, and cleavage of laminin-5 gamma2 chains were assessed by Western blot analysis, immunohistochemistry, and zymography in OSC cell lines (OSC-4 and NOS-2, highly invasive; OSC-7, weakly invasive) and their xenografts in severe combined immunodeficient (SCID) mice. The influence of claudin-1 small interfering RNA (siRNA) on the invasion activity of the cell lines was also investigated. Compared with OSC-7, both OSC-4 and NOS-2 more strongly expressed claudin-1 and possessed high activities of MMP-2 and MMP-9. Tumors formed in the tongues of SCID mice xenografted with OSC-4, NOS-2, and OSC-7 immunohistochemically revealed strong, moderate, and weak expression of laminin-5 gamma2 chains, respectively, and laminin-5 gamma2 chains were secreted in the conditioned medium of the cancer cells in parallel with the in vivo results. Claudin-1 siRNA largely suppressed the invasion of OSC-4 and decreased the activation of MMP-2, the expression of membrane-type MMP-1 (MT1-MMP), and the cleavage of laminin-5 gamma2. In addition, not only antibodies against MT1-MMP and epidermal growth factor receptor (EGFR) but also MMP-2 and EGFR inhibitors strongly suppressed the invasion activity of OSC-4. These results suggest that claudin-1 up-regulates cancer cell invasion activity through activation of MT1-MMP and MMP-2, which results in enhanced cleavage of laminin-5 gamma2 chains.


International Journal of Oral and Maxillofacial Surgery | 1990

Gustatory impairment and salivary gland pathophysiology in relation to oral cancer treatment

Yukinobu Tomita; Tokio Osaki

Gustation and salivation were evaluated in 41 patients with oral carcinoma who were treated preoperatively with Peplomycin (PLM) or PLM + 5-FU + 60CO- radiation. Thresholds for sweet, salt, sour and bitter were originally elevated in many patients. Gustatory impairment increased especially with chemo- and radiotherapy. Recovery, however, took place within a year to almost original levels. Salivation was originally not impaired. Resting salivary flow rate (SFR) of the combined therapy group was decreased to half the initial rate, and a 20% decrease of SFR was seen in the PLM group. Corresponding to SFR, 99mTc uptake of the submandibular glands had declined, and salivary viscosity had increased. Salivary gland damage persisted during the study, and appeared irreversible. It was concluded from these results that taste impairment by oral cancer treatment is temporary, while damage to the salivary glands is permanent.


Oral Surgery, Oral Medicine, Oral Pathology | 1994

Serum cytokines, interleukin-2 receptor, and soluble intercellular adhesion molecule-1 in oral disorders

Tetsuya Yamamoto; Kazunori Yoneda; Eisaku Ueta; Tokio Osaki

Serum levels of soluble intercellular adhesion molecule-1, soluble interleukin-2 receptor, and cytokines such as interleukin-3, interleukin-4, interleukin-6, tumor necrosis factor-alpha, and granulocyte-macrophage colony-stimulating factor were examined in patients with oral disorders with 20 healthy persons used as control subjects. Patients studied included 30 with squamous cell carcinoma, 26 with oral lichen planus, 20 with recurrent aphthous ulcer, 19 with acute odontogenic bacterial infection, 16 with pseudomembranous candidiasis, and 16 with herpetic gingivostomatitis. Compared with levels in control subjects, detectable serum levels of interleukin-3 (> or = 10 pg/ml) existed more frequently in pseudomembranous candidiasis (13/16), acute odontogenic bacterial infection (14/19), and squamous cell carcinoma (24/30) and of granulocyte-macrophage colony-stimulating factor (> or = 4 pg/ml) more frequently in recurrent aphthous ulcer (15/20) and squamous cell carcinoma (21/30). These cytokine levels were increased with T stage of squamous cell carcinoma. About 20 pg/ml of interleukin-4 was detected in serum from one third to one fourth of patients with oral lichen planus, recurrent aphthous ulcer, and squamous cell carcinoma. Tumor necrosis factor-alpha was hardly detected in most patients except those with oral lichen planus and squamous cell carcinoma in which about one third of the patients had more than 40 pg/ml of tumor necrosis factor-alpha in serum. More than 10 pg/ml of interleukin-6 was frequently detected in all disorders, especially recurrent aphthous ulcer (18/20), pseudomembranous candidiasis (12/16), and acute odontogenic bacterial infection (17/19).(ABSTRACT TRUNCATED AT 250 WORDS)


The American Journal of the Medical Sciences | 1999

Treatment of Xerostomia with the Bile Secretion-Stimulating Drug Anethole Trithione: A Clinical Trial

Toshihiro Hamada; Tomoko Nakane; Tsuyoshi Kimura; Kazuhiro Arisawa; Kazunori Yoneda; Tetsuya Yamamoto; Tokio Osaki

BACKGROUND Saliva protects the oral mucosa, inhibiting microbial overgrowth. Hyposalivation, therefore, induces multiple oral disorders, although treatment of hyposalivation is very difficult. METHODS A cholagogue, anethole trithione (AT) was administered to patients with symptomatic hyposalivation (xerostomia) caused by senile hypofunction (4 men and 17 women; senile group), medications (6 men and 17 women; drug group), and oral cancer therapy (two men and three women; cancer group). For control groups, an artificial saliva was administered to 45 patients consisting of senile hypofunction (10 men and 16 women), drug-induced xerostomia (3 men and 10 women) and oral cancer therapy-induced xerostomia (four men and two women). RESULTS Two weeks after administration of AT (6 tablets per day), both nonstimulated salivary flow rate (SFR) and stimulated SFR increased in a statistically significantly manner from 0.76 +/- 0.41 and 5.18 +/- 3.02 to 1.54 +/- 1.33 (P<0.05) and 9.07 +/- 4.10 mL/10 min (P<0.05), respectively. Of the three groups, the drug group showed the largest increases in both SFRs, from 0.90 +/- 0.54 and 6.29 +/- 4.12 to 1.69 +/- 1.65 and 12.09 +/- 5.10 mL/10 min (P<0.05 and P<0.02, respectively). Patients in the control group had almost constant SFRs. After AT administration, the salivary viscosity was, however, mildly decreased and concentrations of secretory-immunoglobulin A, lactoferrin, potassium, and chloride in nonstimulated saliva were almost constant. Corresponding with the increase of salivation, oral discomfort and inflammation were improved or resolved in 41 patients of the AT group within about 4 weeks, whereas improvement was observed in only nine patients of the control group. CONCLUSIONS These results indicate that AT sufficiently stimulates salivation and improves xerostomia.


European Journal of Cancer. Part B: Oral Oncology | 1996

Low malignant intraductal carcinoma on the hard palate: a variant of salivary duct carcinoma?

Yukihiro Tatemoto; A. Ohno; Tokio Osaki

A rare, minor salivary gland tumour of the hard palate in a middle-aged woman was presented. The small (1.0 X 0.5 cm in diameter) hemispherical tumour was well circumscribed with a fine papillomatous surface. Histopathologically, tumour cells with eosinophilic cytoplasm and a large nucleus were single-strand cuboidal and columnar cells, which showed intraductal growth exhibiting a cribriform pattern. The histological features were distinct from adenoid cystic carcinoma and polymorphous low-grade adenocarcinoma because the tumour lacked the neurotropic infiltration, cord-like proliferation and targetoid arrangement. The tumour could not be identified as a typical salivary-duct carcinoma because Roman bridging, papillary projection, and severe cell atypia were not found. Tumour cells were negative for PAS, Alcian blue, mucicarmine, p53, c-erbB-2, CEA, S-100 protein, alpha-smooth muscle actin, lactoferrin or vimentin. About 5% of the tumour cells were positive for proliferating cell nuclear antigen. Taking these factors into account, together with the clinical features, the name low malignant intraductal carcinoma seems appropriate.


The American Journal of the Medical Sciences | 2000

Candidiasis May Induce Glossodynia without Objective Manifestation

Tokio Osaki; Kazunori Yoneda; Tetsuya Yamamoto; Eisaku Ueta; Tsuyoshi Kimura

BACKGROUND The causes of glossodynia in the absence of objective abnormalities range widely and differential diagnosis of glossodynia is very difficult. METHODS Based on the examination results of peripheral blood, stimulated and nonstimulated salivary flow rate (SFR), glossal pain threshold, and C. albicans cell culture and the response to treatment, we identified the cause of vague pain of the tongue in 98 patients who lacked objective findings and identified candidiasis as the cause of glossodynia in 26 patients. RESULTS These patients revealed hyposalivation and decreased glossal pain thresholds and C. albicans cell overgrowth. Pain thresholds in the painful portion (54.6+/-2.9 degrees C) were significantly decreased compared with those in the painless portion (57.7+/-3.4 degrees C) (P < 0.05) and the pain thresholds were largely increased after treatment (57.2+/-1.6 degrees C). Nonstimulated SFR before treatment was lower than that of age- and gender-matched healthy people, although stimulated SFR was decreased only slightly. C. albicans cell overgrowth was detected by the number of C. albicans colonies that formed in Sabourauds agar plate (539.3+/-198.4/dish). After the subsidence of glossal pain by mouth washing with a 3% amphotericin B solution, the C. albicans colonies were decreased to 31.5+/-19.3/dish, which was almost same as the control level, 14.1+/-8.4/dish. CONCLUSION These results indicate that candidiasis in conjunction with hyposalivation may induce pain in the tongue without manifestation of objective abnormalities.


Pathology Research and Practice | 1998

Expression of p53 and p21 Proteins in Oral Squamous Cell Carcinoma : Correlation with Lymph Node Metastasis and Response to Chemoradiotherapy

Yukihiro Tatemoto; Tokio Osaki; Kazunori Yoneda; Tetsuya Yamamoto; Eisaku Ueta; Tsuyoshi Kimura

p53 protein, a product of the p53 cancer suppressor gene, and p21 protein, a cyclin-dependent kinase inhibitor, were immunohistochemically investigated in 150 oral squamous cell carcinomas (SCCs) and the relationship between their expression and clinicopathological findings were evaluated. The positivity for p53 and p21 proteins was not correlated with the T-stage, mode of tumor cell invasion or tumor cell differentiation. However, the expression of p53 and p21 proteins was correlated with lymph node metastasis. Of 62 SCCs with regional lymph node metastasis, 45 SCCs (72.6%) were positive for p53 while 45 (52.9%) of 88 SCCs without metastasis expressed p53 protein (p < 0.02). In addition, p21 protein was observed in 25 (38.5%) and 18 (21.2%) SCCs with and without metastasis, respectively (p < 0.05). Furthermore, p53 protein was inversely correlated with the histopathological effect of inductive chemoradiotherapy; the rate of chemoradiotherapy-induced lethal degeneration (56.7%) in p53-negative SCCs was significantly higher than that (28.9%) in p53-positive SCCs (p < 0.005). However, no clear difference in the effect was observed between p21-positive and p21-negative SCCs. Finally, the 5-year-survival rate was highest in p53(-)-p21(+) (80.0%) followed by 76.3% in p53(-)-p21(-), 65.9% in p53(+)-p21(+) and 65.4% in p53(+)-21p(-) SCCs. These results indicate that although the expression of p21 protein is only weakly correlated with the clinico-histopathological findings, p53 protein is a useful prognostic marker and that inductive chemoradiotherapy can be successfully planned by immunohistochemical examination of p53 protein.


European Journal of Cancer. Part B: Oral Oncology | 1994

Tumorigenicity of cell lines established from oral squamous cell carcinoma and its metastatic lymph nodes

Tokio Osaki; Yukihiro Tatemoto; Kazunori Yoneda; Tetsuya Yamamoto

We investigated the biological and histopathological characteristics of seven human tumour cell lines established from primary tongue squamous cell carcinoma (OSC-1), from metastasised lymph nodes of the gingival carcinoma (OSC-2 and OSC-3) and from tongue carcinoma (remaining four lines). The doubling time ranged from 22 h (OSC-2 and OSC-4) to 55 h (OSC-7), and did not correlate with tumour cell stratification in a collagen gel matrix. An invasive tendency was most prominent in OSC-2 and OSC-4; with the other cell lines, except OSC-6 and OSC-7, only a few sporadic invading cells were found in the tissue culture. In the cell lines established from the metastatised tumours, originally exhibiting grade 3 invasion, the invasion became more sporadic when the tumour cells were xenografted into the tongues of nude mice, while an invasion similar to the original was observed in the cell lines obtained from the original site (OSC-1) and from tumours of Grade 4C invasion. These findings suggest that the biological behaviour of the established tumour cells is markedly different even in tumours of the same tissue origin, and strongly invasive cells may selectively invade, and metastatise to the lymph nodes.


European Journal of Cancer. Part B: Oral Oncology | 1995

An immunohistochemical study of odontogenic mixed tumours

K. Yamamoto; Kazunori Yoneda; Tetsuya Yamamoto; E. Ueta; Tokio Osaki

Five cases of odontogenic mixed tumour comprising of an ameloblastic fibroma, an adenomatoid odontogenic tumour, an odonto-ameloblastoma and two ameloblastic fibro-odontomas were immunohistochemically investigated. Odontogenic epithelial cells were fully positive for cytokeratin detected by antibody KL-1, although there were some differences in its intensity. In contrast, for tenascin, only immature dental papilla-like mesenchymal tissue, especially around the dental lamina-like odontogenic epithelium, was positive, while the myxomatous area and connective tissue were negative. Positive vimentin staining was observed in some areas of immature dental papilla-like cells as well as the basement membrane of odontogenic epithelium in the ameloblastic fibroma, suggesting that this tumour had developed at the early stage of tooth formation. Proliferating nuclear cell antigen-positive cells were generally rarely seen, but were frequently observed in epithelial cells of the ameloblastic fibroma and odonto-ameloblastoma. These observations suggest that tumour cells in each odontogenic mixed tumour possess characteristic proteins associated with proliferation potential and that ameloblastic fibroma and odonto-ameloblastoma have higher proliferation potential among the tumours examined.


Journal of Oral and Maxillofacial Surgery | 1995

Angiomyolipoma of the oral cavity: Report of two cases

Kazuhiko Yamamoto; Hitoshi Nakamine; Tokio Osaki

16. Kay S, Elzay RP, Willson MA: Ultrastructural observations on a gingival granular cell tumor (congenital epulis). Cancer 27:674, 1971 17. Sobel HJ, Marquet E, Avrin E, et al: Granular cell myohlastoma: An electron microscopic and cytochemical study illustrating the genesis of granules and aging of myoblastoma cells. Am J Pathol 65:59, 1971 18. Miller AS, Leifer C, Chen S-Y, et al: Oral granular cell tumors: Report of twenty-five cases with electron microscopy. Oral Surg Oral Med Oral Pathol 44:227, 1977 19. Zarbo RJ, Lloyd RV, Beals TF, et al: Congenital gingival granular cell tumor with smooth muscle cytodifferentiation. Oral Surg Oral Med Oral Pathol 56:512, 1983 20. Nistal M, Paniagua R, Picazo ML, et al: Granular changes in vascular leiomyosarcoma. Virchows Arch [A] 386:239, 1980 21. Gold L, Christ T: Granular-cell odontogenic cyst: An unreported odontogenic lesion. Oral Surg Oral Med Oral Pathol 29:437, 1970 22. Buchner A: Granular-cell odontogenic cyst. Oral Surg Oral Med Oral Pathol 36:707, 1973 23. Slootwig P, deWilde P, Vooijs P, et al: Oral granular cell lesions: An immunohistochemical study with emphasis on intermediate-sized filaments proteins. Virchows Arch [A] 402:35, 1983 24. Damm DD, Cibull ML, Geissler RH, et al: Investigation into the histogenesis of congenital epulis of the newborn. Oral Surg Oral Med Oral Pathol 76:205, 1993 25. Nadji M, Morales AR (eds): Immunoperoxidase techniques: A practical approach to tumor diagnosis. Chicago, IL, American Society of Clinical Pathologists Press, 1986, p 35 26. Miettinen M, Lehtonen E, Lehtola H, et al: Histogeneisis of granular cell tumor: An immunobistochemical and ultrastructural study. J Patbol 142:221, 1984 27. Regezi JA, Zarbo RJ, Courtney RM, et al: Immunoreactivity of granular cell lesions of skin, mucosa and jaw. Cancer 64:1455, 1989 28. Armin A, Connelly EM, Rowden G: An immunoperoxidase investigation of S-100 protein in granular cell myoblastomas: Evidence for Schwann cell derivation. Am J Clin Pathol 79:37, 1983 29. Logothetou-Rella H, Karayiannis A, Vamvassakis E, et al: A cytologic, ultrastructural and immunocytochemical comparison of tumor cells and cell cultures originating in invasive bladder carcinoma. Eur Urol 21:146, 1992 (Switzerland) 30. Wang LT: Imrnunohistochemical study on clear cell chondrosarcoma. Chung Hua Chung Liu Tsa Chih 13:306, 1991 (China) 31. Wright JA, Goonetilleke UR, Waghe M, et al: An immunohistochemical study of spontaneous histiocytic tumors in the rat. J Comp Pathol 104:223, 1991 32. Neri A, Bohoslawec O, Anderson TD, et al: Differential release of active proteinase inhibitors by two rat mammary adenocarcinoma variants possessing different metastatic potentials. Cancer Res 51:1318, 1991

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