Hitoshi Nagatsuka

Matsumoto Dental University, Shiojiri, Nagano-ken, Japan

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Publications (228)338.27 Total impact

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    ABSTRACT: Mineralization is one of the most important processes in normal bone tissue development and in disease condition. Developing a novel and standardized in vitro model system that can readily monitor both cellular dynamics and mineralization is crucial for better understanding the bone tissue development and growth. Recent studies indicated that the mechanical environment is critical condition in mineralization. We hypothesized that hydrogel with different mechanical stiffness can provide a biomimetic mechanical environment that can modulate bone tissue growth and mineralization. A femur of mouse embryo (E16) was embedded in agarose hydrogel (2-60 kPa) and cultured in osteogenic medium for a week. Micro computed tomography (µCT) results revealed the enhanced mineralization was detected in femur head cultured in the gel condition, while no mineralization in the femur head cultured in control (floating culture) condition. The mineralized region was corresponding to the region of secondary ossification center. Both histological and quantitative analyses indicated that the mineralized region of femur head cultured in 10 kPa gel condition was the highest and the mineralized area was significantly larger than that cultured in 2, 40 and 60 kPa gel condition. Immunofluorescence results indicated that the enhanced mineralization caused by the higher chondrogenic differentiation at that region. This enhancement mainly relating to the mechanical forces not to the oxygen tension was also confirmed. Since this system enhances and shorten the mineralization procedure compared to the conventional 2D or 3D cell culture system, this hydrogel system would be one of the unique models for better understanding the mineralized tissue development.
    Tissue Engineering Part C Methods 11/2014; · 4.64 Impact Factor
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    ABSTRACT: Objective: This study examined whether the occurrence of late neck metastasis in early tongue squamous cell carcinoma can be predicted by evaluating HMGB1 (high mobility group box 1) expression in the primary lesion. Methods: A case-control study was conducted. The cases comprised 10 patients with late neck metastasis. The controls consisted of 16 patients without recurrence. All were examined immunohistochemically for HMGB1 protein expression. The odds ratio for late neck metastasis in relation to HMGB1 was estimated. Results: Results for HMGB1 were dichotomised into positive staining scores (score, 5-7) and negative scores (0-4). Six cases (60 per cent) and four controls (25 per cent) were HMGB1-positive. Although no significant result was seen, compared with HMGB1-negative patients the odds ratio for late neck metastasis in HMGB1-positive patients was 3.8 (95 per cent confidence interval, 0.6-26.5) after adjusting for other factors. Conclusion: In the present study, immunohistochemical study of HMGB1 in early tongue squamous cell carcinoma did not appear to be very useful for predicting occult neck metastasis. Further study is necessary to clarify the relationship between HMGB1 expression and late neck metastasis in early tongue squamous cell carcinoma.
    The Journal of laryngology and otology. 09/2014;
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    ABSTRACT: Abstract Conclusion: In tongue squamous cell carcinoma (SCC), high levels of regulatory T-cell (Treg) infiltration in tumor nests are observed in the cases with poor prognosis. Objectives: The role of Tregs in head and neck cancers remains unclear. The aim of this study was to observe the distribution of Tregs in different stages of tongue SCC and estimate the effects on prognosis. Methods: Thirty-four cases with tongue SCC were examined immunohistochemically for CD4, CD8, and Forkhead box P3 (Foxp3). Immunoreactive cells were counted in cancer stroma and nest regions, and relationships between cell numbers and disease-free survival rates were analyzed. Results: In the 34 cases, univariate analysis for disease-free survival indicated high-level infiltration of Tregs (CD4(+)Foxp3+) into both cancer nests and stroma and presence of helper T (CD4(+)Foxp3-) cells in cancer stroma as potential predictors of significantly worse prognosis. In early-stage cases (stage I/II), high-level infiltration of Tregs in cancer nests correlated significantly with poor disease-free survival rate. Multivariate analysis for disease-free survival found no independent variables.
    Acta oto-laryngologica. 06/2014;
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    ABSTRACT: Dexmedetomidine, a highly selective agonist of α2-adrenoceptors, is a commonly used sedative; however, a potent anti-inflammatory effect has also been found. In the present study we evaluated the inhibitory effect of locally injected dexmedetomidine on inflammatory responses in the injected region. Local inflammation was induced in the hindpaws of male mice (aged 6-8 weeks) by intraplantar injection of lambda-carrageenin. To offset the central effect of tested agents, different agents were blindly injected into the left and right paws in the pairs of comparison. The effect of dexmedetomidine on edema (increase in paw volume), the accumulation of leukocytes, and production of tumor necrosis factor-α (TNF-α) and cyclooxygenase-2 (COX-2) were evaluated after carrageenin injection, using water displacement plethysmometry, histological imaging, immunohistochemistry, and Western blotting analysis. Furthermore, we also evaluated the effect of yohimbine, a full antagonist of α2-adrenoceptors, and phenylephrine, an agonist of the α1-adrenoceptor, on dexmedetomidine's action on inflammatory responses. Paw volume and amount of leukocytes in the injected region significantly increased after the injection of carrageenin. Similarly, TNF-α and COX-2 production was found in the subcutaneous region injected with carrageenin, 4 hours after injection. Dexmedetomidine significantly inhibited all increases in paw volume, leukocytes, and production of TNF-α and COX-2. Furthermore, yohimbine significantly antagonized the anti-inflammatory effects of dexmedetomidine, whereas phenylephrine did not significantly alter them. The findings suggest that locally injected dexmedetomidine exhibits an anti-inflammatory effect against local acute inflammatory responses, mediated by α2-adrenoceptors.
    Anesthesia and analgesia 02/2014; 118(2):473-80. · 3.08 Impact Factor
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    ABSTRACT: Adenoid cystic carcinoma (ACC) is one of the most common salivary gland malignant tumors with a high risk of recurrence and metastasis. Current studies on cancer stem cells (CSCs) have verified that CSCs are the driving force behind tumor initiation and progression, suggesting that new cancer therapies may be established by effectively targeting and killing the CSCs. The primary goal of this study is to investigate the expression patterns of ABCG2, CD133, and podoplanin in ACC of minor salivary glands by immunohistochemistry analysis. We found that ABCG2 was weakly expressed in normal looking salivary gland tissues. A significant upregulation of ABCG2 expression in ACC was observed with a similar expression pattern of Ki-67. CD133 was detected in apical membrane of epithelial cells and podoplanin was expressed positively in myoepithelial cells of both normal looking tissue and ACC. However, no significant difference was found of the expression pattern of CD133 and podoplanin between normal looking tissues and ACC. Our observations suggest that CSCs may exist in quiescent cells with ABCG2 positive staining, which are surrounded by cells with positive expression of ABCG2 and Ki-67 in ACC, and costaining with ABCG2 and Ki-67 may help predict the location of CSCs.
    BioMed research international. 01/2014; 2014:132349.
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    ABSTRACT: We previously reported that dynamic contrast-enhanced MRI parameters and time–signal intensity curves (TICs; also known as contrast index curves) are useful for the differential diagnosis of jawbone lesions. In particular, odontogenic fibroma and ossifying fibroma, which possess similar histopathological features (i.e., a mixture of hard and soft tissue components), display unique TIC patterns, and we consider that the TIC patterns of these lesions reflect their hard and soft tissue components. Therefore, fibrous dysplasia, which contains fibrous tissue and immature isolated trabeculae composed of woven bone, is expected to display an interesting TIC. The purpose of this study was to assess the utility of TICs for differentiating between the abovementioned lesions, which have similar histopathological components.
    Oral Radiology 01/2014; 30(1). · 0.17 Impact Factor
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    ABSTRACT: Objectives To determine the distribution patterns of bone resorption regulators, RANK, RANKL and OPG in recurrent ameloblastomas (RA) and to clarify their impact on the biological behavior of these neoplasms. Materials and methods Fifteen paraffin-embedded RA cases were subjected to immunohistochemistry for expression of RANK, RANKL and OPG. Results RANK-RANKL-OPG triad was heterogeneously detected in RA samples. RANK, essential for osteoclast differentiation, was strongly expressed in tumoral epithelium. Conversely, RANKL, an osteoclast activator, was markedly underexpressed, and protein localization was predominantly stromal. OPG, an osteoclastogenesis inhibitory factor, was detected in neoplastic epithelium>stroma, suggesting functional inactivation of RANKL. Most RA (n=12/15; 80%) exhibited a bimolecular spatial expression pattern, the most common being RANK-positive/OPG-positive(n=8/15; 53.3%). All three proteins showed no significant correlation with the clinical/histopathological parameters in RA patients(P>.05) Conclusions The RANK+/RANKLlow/-/OPG+ phenotype observed in RA suggests an altered local bone metabolism characterized by low bone resorptive activity in these recurrent tumors.
    Oral Surgery, Oral Medicine, Oral Pathology, Oral Radiology, and Endodontology 01/2014; · 1.50 Impact Factor
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    ABSTRACT: Nestin is an intermediate filament that was first identified in neural progenitor cells. It is expressed in various cell types in the nervous system as well as in other systems. In the present study, we investigated nestin expression in non-neoplastic salivary gland tissue and in salivary gland tumors. In non-neoplastic salivary glands, nestin expression was observed in only a few abluminal cells. In contrast, diffuse nestin staining was observed in the abluminal cells of pleomorphic adenoma (11 of 11 cases), basal cell adenoma (7 of 7 cases), and epithelial-myoepithelial carcinoma (2 of 2 cases). The stromal cells in basal cell adenoma also expressed nestin. In adenoid cystic carcinoma (6 of 7 cases) and polymorphous low-grade adenocarcinoma (3 of 3 cases), nestin positive cells were observed focally. Nestin was not detected in Warthin tumor (6 cases), classical acinic cell carcinoma (2 cases), mucoepidermoid carcinoma (5 cases), or salivary duct carcinoma (4 cases). Because the nestin expression pattern in each histological salivary gland tumor type is unique, nestin could be a very useful abluminal cell marker for the diagnosis of salivary gland tumors.
    Pathology International 10/2013; 63(10):496-501. · 1.72 Impact Factor
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    ABSTRACT: In recent years, artificial biological materials have been commonly used for the treatment of bone tissue defects caused by trauma, tumors, or surgical stress. Although tricalcium phosphate (TCP) is a promising absorbent bone tissue reconstruction biomaterial, it has been reported that its biocompatibility and osteoconductivity depend on its preparation method and sintering temperature. In addition, although it is thought that the microenvironment produced by the extracellular matrix plays an important role in cell growth and differentiation, there have been few studies on how the geometric structure of artificial biological materials affects cells. In the present study, a new honeycomb TCP scaffold containing through-holes with diameters of 300 µm has been developed. The influence of the sintering temperature on the crystal structure and material properties of the honeycomb TCP scaffold was investigated using scanning electron microscopy and X-ray diffraction. Its biocompatibility and osteoconductivity were also evaluated by implantation into experimental animals. It was found that a β-TCP scaffold sintered at 1200°C exhibited high biocompatibility and osteoconductivity, and when it was loaded with BMP-2, it exhibited both osteoconductivity and osteoinductivity, promoting rapid bone formation in both ectopic and orthotopic areas. It is thus a highly promising bone reconstruction material that is expected to find clinical applications. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2013.
    Journal of Biomedical Materials Research Part A 09/2013; · 2.83 Impact Factor
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    ABSTRACT: Ever since protoporphyrin IX (PpIX) was discovered to accumulate preferentially in cancer cells after 5-aminolevulinic acid (ALA) treatment, photodynamic treatment or therapy (PDT) has been developed as an exciting new treatment option for cancer patients. However, the level of PpIX accumulation in oral cancer is fairly low and insufficient for PDT. Ferrochelatase (FECH) and ATP-binding cassette transporter G2 (ABCG2) are known to regulate PpIX accumulation. In addition, serum enhances PpIX export by ABCG2. We investigated here whether and how inhibitors of FECH and ABCG2 and their combination could improve PpIX accumulation and PDT efficacy in an oral cancer cell line in serum-containing medium. ABCG2 inhibitor and the combination of ABCG2 and FECH inhibitors increased PpIX in the presence of fetal bovine serum (FBS) in an oral cancer cell line. Analysis of ABCG2 gene silencing also revealed the involvement of ABCG2 in the regulation of PpIX accumulation. Inhibitors of FECH and ABCG2, and their combination increased the efficiency of ALA-PDT even in the presence of FBS. ALA-PDT-induced cell death was accompanied by apoptotic events and lipid peroxidation. These results suggest that accumulation of PpIX is determined by the activities of ABCG2 and FECH and that treatment with a combination of their inhibitors improves the efficacy of PDT for oral cancer, especially in the presence of serum.
    Acta medica Okayama 06/2013; 67(3):153-164. · 0.65 Impact Factor
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    ABSTRACT: Tooth tissue engineering offers very attractive perspectives for elaboration of regenerative treatments, which enables to cure tooth loss and restore quality of life of the patients. To elaborate such treatment, isolation and culture of dental pulp cell must be achieved as a key element. In this article, we report the establishment of a stable cell line from GFP transgenic rat dental pulp, named TGC (Tooth Matrix-forming, GFP Rat-derived Cell). TGCs have exhibited odontoblastic feature both in vitro and in vivo. In vitro, TGC exposed to osteogenic medium demonstrated collagen fiber synthesis with matrix vesicle and mineralization and formed a sheet-like substrate on the cell culture dish. Increased ALP activity and elevated transcription level of various genes involved in calcification and dentin formation were also observed. In vivo, transplanted TGC in SCID mice with β-TCP particles formed dentin-like and pulp-like structure with lining odontoblast. Notably, even after up to 80 passages, TGCs retain their morphological features and differentiation ability. To our knowledge, this is the first report of a dental pulp-derived cell with such stable odontoblastic characteristics. TGC could be a very useful model for further study on dental pulp cell.
    Journal of Oral Pathology and Medicine 05/2013; · 2.06 Impact Factor
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    ABSTRACT: OBJECTIVE: To evaluate the diagnostic value of magnetic resonance imaging (MRI) for odontogenic tumours. MATERIALS AND METHODS:51 patients with odontogenic tumours were subjected to pre-operative MRI examinations. For tumours with liquid components, i.e. ameloblastomas and keratocystic odontogenic tumours (KCOTs), the signal intensity (SI) uniformity of their cystic components (UΣ) was calculated and then their UΣ values were compared. For tumours with solid components that had been examined using dynamic contrast-enhanced MRI (DCE-MRI), their CImax (maximum contrast index), Tmax (the time when CImax occurred), CIpeak (CImax × 0.90), Tpeak (the time when CImax occurred) and CI300 values (i.e. the CI observed at 300 s after contrast medium injection) were determined from CI curves. We then classified the odontogenic tumours according to their DCE-MRI parameters. RESULTS: Significant differences between the UΣ values of the ameloblastomas and KCOT were observed on T1 weighted images (T1WIs), T2 weighted images (T2WIs) and short TI inversion recovery (STIR) images. Depending on their DCE-MRI parameters, we classified the odontogenic tumours into the following five types: Type A: CIpeak > 2.0 and Tpeak < 200 s, Type B: CIpeak < 2.0 and Tpeak < 200 s, Type C: CI300 > 2.0 and Tmax < 600 s, Type D: CI300 > 2.0 and Tmax > 600 s and Type E: CI300 < 2.0 and Tmax > 600 s. CONCLUSION: Cystic component SI uniformity was found to be useful for differentiating between ameloblastomas and KCOT. However, the DCE-MRI parameters of odontogenic tumours, except for odontogenic fibromas and odontogenic myxomas, contributed little to their differential diagnosis.
    Dentomaxillofacial Radiology 03/2013; · 1.27 Impact Factor
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    ABSTRACT: Oral squamous cell carcinoma (OSCC) is thought to arise as the result of cumulative genetic or epigenetic alterations in cancer-associated genes. We focused on the Dickkopf-3 (Dkk-3) gene as a candidate tumor suppressor in OSCC. Dkk-3 is a potential tumor suppressor, and its downregulation has been reported in various types of malignancies. However, our previous data demonstrated that the Dkk-3 protein was dominantly expressed in OSCC tissue, and its expression was correlated with a high incidence of metastasis and with poor prognosis. In order to explain this paradox, we performed functional analyses of the Dkk-3 gene in cancer cell lines. RT-PCR revealed that Dkk-3 mRNA expression was observed in OSCC-derived cell lines but not in gastrointestinal or colorectal adenocarcinoma‑derived cell lines. The siRNA for Dkk-3 was transfected into Dkk-3-expressing cells, and the changes in cell proliferation, invasion and migration were assessed. The knockdown of Dkk-3 mRNA by siRNA transfection did not affect cell proliferation, but it significantly decreased cell migration and invasion. To further investigate the precise mechanism that contributes to the potential oncogenic function of Dkk-3, the Wnt canonical pathway and non-canonical pathways were assessed. Western blotting demonstrated that the effect of Dkk-3 knockdown on cell migration or invasion was not caused by activation of the Wnt pathways. These data demonstrated that Dkk-3 expression in OSCC was different than that in adenocarcinomas. Dkk-3 may possess an oncogenic function that is independent of Wnt signaling.
    Oncology Reports 01/2013; · 2.30 Impact Factor
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    ABSTRACT: Purpose of the research Tooth germ development involves multiple events, including cell proliferation and cell differentiation. Connective tissue growth factor (CTGF/CCN2) is a signaling protein involved in tooth germ development, and we investigated how it is expressed and what roles it may have in primary cultures of mesenchymal cells derived from the developing tooth germ. We also examined the expression of CCN2 in a human odontogenic myxofibroma, a benign tumor of odontogenic mesenchymal origin, and considered the possible roles of CCN2 in the development of myxofibromas. Materials and methods Mesenchymal cells of early bell-stage tooth germs were isolated from Day-90 bovine embryos and placed in primary culture. A resected specimen from a patient with odontogenic myxofibroma was prepared for immunohistochemical studies. Principal results The CCN2 expression level in proliferating odontogenic mesenchymal cells freshly isolated from the early bell stage of developing bovine tooth germs and placed in primary culture was 3 times higher than that in the confluent non-proliferating cells. Recombinant CCN2 significantly increased the proliferation and type I collagen expression in odontogenic mesenchymal cells in primary culture. Immunohistochemical analysis on myxofibroma case revealed that CCN2 was detectable in MIB-1, a cellular marker of proliferation-positive odontogenic mesenchymal cells adjacent to capillary blood vessels and in the endothelial cells of the vessels in the tumor. Major conclusion CCN2 signaling would influence the proliferation of and extracellular matrix production by dental mesenchymal cells. Our results suggest that the same mechanisms of CCN2 action toward dental mesenchymal cells would also be operative in the odontogenic myxofibroma microenvironment.
    International Journal of Oral Science 01/2013; · 2.72 Impact Factor
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    ABSTRACT: The purpose of this study was to evaluate the radiological and histopathological findings of 11 patients with unerupted first molars to verify the factors obstructing spontaneous eruption. The patients' clinical, radiological, and histopathological data were evaluated retrospectively to determine histopathological diagnosis, radiographic findings, methods of surgical management, and postoperative course. This study involved 4 male and 7 female patients (mean age=9.5 years old). Nine cases involved the mandible. The patients' histopathological diagnoses included 3 odontogenic tumors, 2 odontogenic cysts, and 6 hyperplastic dental follicles. Radiographically, 10 cases showed characterless enlargement of the follicular space, while only 1 displayed radiopaque bodies. One patient with a tumor underwent enucleation, and 1 with a cyst underwent cystectomy and tooth extraction. The others underwent wide excision or partial excision of the surrounding tissue at the top of the impacted tooth. Tumor relapse was observed in 3 cases. Surgeons should perform aggressive treatment for patients with unerupted teeth because spontaneous eruption is rare in cases involving non-neoplastic lesions such as hyperplastic dental follicles.
    Pediatric dentistry. 01/2013; 35(1):67-70.
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    ABSTRACT: Background: Bone marrow-derived cells (BMCs) have abilities of cell migration and differentiation into tissues/organs in the body and related with the differentiation of teeth or periodontal tissue including fibroblasts. Then, we examined the effect of orthodontic mechanical stress to the transplanted BMC migration into periodontal tissues using BMC transplantation model. Material and Method: BMC from green fluorescence protein (GFP) transgenic mice were transplanted into 8-week-old female C57BL/6 immunocompromised recipient mice, which had undergone 10 Gy of lethal whole-body-irradiation. Five mice as experimental group were received orthodontic mechanical stress using separator between first molar (M1) and second molar (M2) 1 time per week for 5 weeks and 5 mice as control group were not received mechanical stress. The maxilla with M1 and M2 was removed and was immunohistochemically analyzed using a Dako Envision + Kit-K4006 and a primary anti-GFP-polyclonal rabbit antibody. Immunohistochemically stained was defined as positive area and the pixel number of positive area in the periodontal tissue was compared with the previously calculated total pixel number of the periodontal tissue. Results: The immunohistochemistry revealed that GFP positive cells were detected in the periodontal tissues, both in the experimental and control specimens. The ratio of pixel number in the examination group showed 5.77 ± 3.24 % (mean ± SD); and that in the control group, 0.71±0.45 % (mean ± SD). The examination group was significantly greater than that of control group (Mann-Whitney U test: p<0.001). Conclusion: These results suggest that orthodontic mechanical stress accelerates transplanted BMC migration into periodontal tissues.
    International journal of medical sciences 01/2013; 10(10):1321-6. · 2.07 Impact Factor
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    ABSTRACT: Bone healing is a complex and multistep process in which the origin of the cells participating in bone repair is still unknown. The involvement of bone marrow-derived cells in tissue repair has been the subject of recent studies. In the present study, bone marrow-derived cells in bone healing were traced using the GFP bone marrow transplantation model. Bone marrow cells from C57BL/6-Tg (CAG-EGFP) were transplanted into C57BL/6 J wild mice. After transplantation, bone injury was created using a 1.0-mm drill. Bone healing was histologically assessed at 3, 7, 14, and 28 postoperative days. Immunohistochemistry for GFP; double-fluorescent immunohistochemistry for GFP-F4/80, GFP-CD34, and GFP-osteocalcin; and double-staining for GFP and tartrate-resistant acid phosphatase were performed. Bone marrow transplantation successfully replaced the hematopoietic cells into GFP-positive donor cells. Immunohistochemical analyses revealed that osteoblasts or osteocytes in the repair stage were GFP-negative, whereas osteoclasts in the repair and remodeling stages and hematopoietic cells were GFP-positive. The results indicated that bone marrow-derived cells might not differentiate into osteoblasts. The role of bone marrow-derived cells might be limited to adjustment of the microenvironment by differentiating into inflammatory cells, osteoclasts, or endothelial cells in immature blood vessels.
    Calcified Tissue International 12/2012; · 2.75 Impact Factor
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    ABSTRACT: The aim of this study was to determine the expression of essential osteogenic genes related to the canonic WNT pathway, i.e., WDR5, sFRP-2, and their downstream genes, in ameloblastoma and to clarify their biologic impact on this neoplasm. Forty-six paraffin-embedded ameloblastoma samples and ameloblastic (AM-1) and preosteoblastic (KUSA/A1) cell lines were used. Immunohistochemistry, Western blot, reverse-transcription polymerase chain reaction, and alkaline phosphatase (ALP) activity assay were performed. WDR5, essential for osteoblast differentiation and canonic WNT pathway activation, was negative in most ameloblastoma cases and weakly expressed in AM-1 cells. Conversely, sFRP-2s was overexpressed. RUNX2 and C-MYC, downstream inductions of canonic WNT pathway activation, demonstrated weak mRNA expressions in ameloblastoma, suggesting WNT pathway impairment and WDR5 functional inactivity. Recombinant WDR5 weakly induced ALP activity of KUSA/A1 cells cultured in AM-1 conditioned medium. These findings suggest that WNT-related bone-forming genes are down-regulated in ameloblastoma. Concurrent sFRP-2 overexpression suggests that both bone-forming and bone-inhibiting genes equally contributed to reduced bone formation in this neoplasm.
    Oral surgery, oral medicine, oral pathology and oral radiology. 12/2012; 114(6):771-7.
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    ABSTRACT: Ossifying fibroma (OF), a rare nonodontogenic tumor, is defined as a bone-related jawbone lesion. The main histopathological feature of OF is the replacement of bone by benign connective tissue. Ossifying fibroma usually occurs in the second to fourth decades of life and shows a predilection for females. Ossifying fibroma most commonly occurs in the mandible, and OF arising from the anterior part of the maxilla is rare. Ossifying fibromas display various radiographic findings, including varying degrees of radiolucency and radiopacity, depending on the proportions of their soft and hard tissue components. Depending on their components, it can be difficult to distinguish OF from other fibroosseous lesions and some odontogenic tumors by using conventional radiographs, computed tomography, and magnetic resonance imaging (MRI). We report a case of OF in the anterior maxilla in a 56-year-old man, together with its histopathological and imaging findings including the dynamic MRI findings.
    Oral surgery, oral medicine, oral pathology and oral radiology. 10/2012; 114(4):e139-46.
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    ABSTRACT: Primary intraosseous squamous cell carcinoma (PIOSCC) is a rare malignant odontogenic tumor arising from odontogenic epithelial remnants within the jawbones. PIOSCC is histopathologically divided into 3 types: solid-type carcinoma, carcinoma derived from a keratocystic odontogenic tumor, and carcinoma derived from an odontogenic cyst. In this article, we report a case of solid-type PIOSCC involving reactive bone formation in the mandible in a 60-year-old female patient together with its histopathological and imaging findings.
    Oral surgery, oral medicine, oral pathology and oral radiology. 09/2012; 114(5):e71-7.

Publication Stats

2k Citations
338.27 Total Impact Points


  • 2001–2013
    • Matsumoto Dental University
      • • Department of Oral Physiology
      • • Institute for Oral Science
      • • Division of Hard Tissue Research
      • • Department of Oral Pathology
      • • Division of Oral and Maxillofacial Biology
      Shiojiri, Nagano-ken, Japan
    • Ohu University
      Hukusima, Fukushima, Japan
  • 1994–2013
    • Okayama University
      • • Department of Oral Pathology and Medicine
      • • Department of Gastroenterological Surgery, Transplant, and Surgical Oncology
      • • Department of Pathology and Oncology
      Okayama, Okayama, Japan
  • 2011
    • Tokushima Bunri University
      • Faculty of Pharmaceutical Sciences
      Tokushima-shi, Tokushima-ken, Japan
  • 2009–2011
    • University of Malaya
      • • Department of Oral Pathology & Oral Medicine & Periodontology
      • • Faculty of Dentistry
      Kuala Lumpur, Kuala Lumpur, Malaysia
  • 2008–2009
    • Wakayama Medical University
      • Department of Otolaryngology-Head and Neck Surgery
      Wakayama, Wakayama, Japan
  • 2006–2009
    • Nagoya City University
      • Department of Pathology
      Nagoya, Aichi, Japan
    • Yamaguchi University
      • Division of Oral and Maxillofacial Surgery
      Yamaguti, Yamaguchi, Japan
  • 2004
    • New York University College of Dentistry
      New York City, New York, United States
  • 1997
    • Kyungpook National University
      • Department of Oral Pathology
      Daikyū, Daegu, South Korea