Clinical Study of 597 Oral Squamous Cell Carcinomas in Our Department - Especially about 318 Tongue Carcinoma

This clinico-statistical study includes 597 cases of oral squamous cell carcinoma treated at the Maxillofacial Surgery Section of Tokyo Medical and Dental University between January 2002 and December 2011. There were 373 male and 224 female patients (male to female ratio, 1.7 : 1), and the median age was 67 years. The tongue (53.3%) was the most commonly affected site. The 5-year disease-specific survival rate was 84.8%. Survival rates by clinical stage were as follows : Stage 1, 92.1% (n=195).; Stage , 86.0% (n = 221) ; Stage III, 77.7% (n=65) ; and Stage IV, 73.8% (n =116). Survival rates by primary site were as follows: tongue, 85.4% (n=318) ; lower gingiva, 82.8% (n =114) upper gingiva, 83.7% (n=59) ; buccal mucosa, 89.1% (n 54) ; oral floor, 81.4% (n=49) ; and hard palate, 100% (n=3). According to clinical growth patterns of Stage I / I tongue cancer cases, the 5-year disease-specific survival rate was significantly higher for patients with the exophytic/superficial type (97.3%, n =173) than for those with the endophytic type (77.5%, n=145). Among Stage I/II tongue cancer cases, the corresponding survival rate was significantly higher for patients who had not previously undergone invasive treatments (n=201), such as tooth extraction, compared to those who had previously done so (n=54) (92.7% and 79.7%, respectively). In addition, the incidence of secondary cervical lymph node metastasis was significantly higher in patients who had previously undergone invasive treatments.

Mandibular reconstruction using a poly(L-lactide) mesh combined with autogenous particulate cancellous bone and marrow: a prospective clinical study

The purpose of this study was to evaluate the stability and viability of mandibular bone regeneration using a poly(L-lactide) (PLLA) mesh and autogenous particulate cancellous bone and marrow (PCBM). Sixty-two procedures were undertaken at eight hospitals (22 malignant tumours, 30 benign tumours, five cysts, two osteomyelitis, two trauma, and one atrophy of the alveolar ridge); the success rate was 84%. The follow-up period was between 9 and 200 months (mean 88.2 months). Consequently, bone regeneration at 6 months postoperation was excellent in 35 cases (57%), good in 17 cases (27%), and poor in 10 cases (16%). In six of the 'poor' cases, the PLLA mesh was removed due to local infection early after surgery. Bone resorption>20% was observed in only one of 46 cases with a follow-up term of >1 year. There were no signs of any other adverse effects except in one case where a section of the tray broke off late in the follow-up period. It is concluded that this method is stable and effective due to favourable morphological and functional recovery and low invasiveness. It may thus be a useful alternative procedure for mandibular reconstruction.

Changes in the psychological characteristics of oral cancer patients in the perioperative period: a quantitative evaluation

We examined the changes in psychological distress and quality of life (QOL) during the perioperative period in oral cancer patients undergoing surgery and investigated the relationship between patient's psychological distress and QOL. Methods. Fifty patients participated. The Hospital Anxiety and Depression Scale (HADS; Japanese version), as a psychological test and the Functional Assessment of Cancer Therapy General (FACT-G); and Head and Neck (FACT-H&N), as quality of life (QOL) surveys were administered preoperatively, after surgery, and 1 month after leaving the hospital. Results. Anxiety was highest pre-operation and depression was highest post-operation, but improvements in both were seen post-discharge. At the pre-operation time point, anxiety and depression low-score groups had significantly high scores on Emotional well-being and Functional well-being. At the post-operation time point, anxiety and depression low-score groups had significantly high scores on all QOL subscales. Conclusion. Providing psychological support while considering anxiety might be particularly useful preoperatively whereas providing psychological support while considering depression might be particularly useful postoperatively.

Potential of tumor-suppressive miR-596 targeting LGALS3BP as a therapeutic agent in oral cancer

The incidence and mortality statistics for oral squamous cell carcinoma (OSCC) were 10th and 12th, respectively, in human cancers diagnosed worldwide in 2008. In this study, to identify novel tumor-suppressive microRNAs (TS-miRNAs) and their direct targets in OSCC, we performed methylation-based screening for 43 miRNAs encoded by 46 miRNA genes located within 500 bp downstream of 40 CpG islands and genome-wide gene expression profiling in combination with a prediction database analysis, respectively, in 18 cell lines, resulting in the identification of a novel TS-miRNA miR-596 directly targeting LGALS3BP/Mac-2 BP/90K. DNA hypermethylation of CpG island located 5'-upstream of miR-596 gene was frequently observed in OSCC cell lines (100% of 18 cell lines) and primary OSCC cases (46.2 and 76.3% of 26 Japanese and 38 Thais primary cases, respectively) in a tumor-specific manner. The ectopic transfection of double-stranded RNA (dsRNA) mimicking miR-596 or specific small interfering RNA for LGALS3BP significantly induced growth inhibition and apoptosis in cell lines lacking miR-596 expression or overexpressing LGALS3BP, respectively, in a manner associated with a suppression of ERK1/2 phosphorylation. Moreover, we also mention the effect of dsRNA mimicking miR-596 on the growth of an OSCC cell line in vivo. Our findings define a central role for miR-596 in OSCC and suggest the potential of miR-596 as an anticancer agent for miRNA replacement therapy in OSCC.

Autocrine motility factor and its receptor expressions in human oral squamous cell carcinoma (SCC) cells

Autocrine motility factor (AMF) a tumor-secreted 55 kDa cytokine induces tumor cell motility by a signal transduction pathway mediated by interaction with its receptor (AMFR) a cell surface glycoprotein of 78 kDa (gp78). Here, AMF secreted by the metastatic LMF4 human oral squamous-cell carcinoma (SCC) cells, induced dose- and time-dependent morphological changes and chemotaxis of the producing cells. Expression of AMFR mRNA was associated with the metastatic ability of SCC cell variants. The data presented show for the first time that SCC cells produce AMF and express AMFR and the expression is related to their invasiveness and metastatic potentials.

Increasing participation of sclerostin in postnatal bone development, revealed by three-dimensional immunofluorescence morphometry

Confocal immunofluorescence tiling imaging revealed the spatio-temporal distributions of osterix and sclerostin in femurs from 3-day-old, 2-week-old and 4-week-old rats to be reciprocally exclusive at the tissue level. Further quantitative three-dimensional immuno fluorescence morphometry demonstrated the increasing distribution of sclerostin in the osteocytic lacuno-canalicular system specifically in diaphysis, which paralleled the cooperative participation and depletion of osterix and β-catenin in adjacent periosteum cells. Treating MC3T3-E1 cells with BIO (a GSK3 inhibitor) induced the stabilization of β-catenin and nuclear translocation of osterix, and negatively regulated osteocalcin/BGLAP and Dmp1. These results collectively demonstrate that the increasing distribution of sclerostin in diaphyseal cortical bone appears to be involved in the attenuation of osterix and β-catenin in adjacent periosteum cells, thus possibly contributing to osteoblast maturation and reducing the osteoblast formation at this bone site. Our confocal microscopy-based imaging analyses provide a comprehensive and detailed view of the spatio-temporal distribution of sclerostin, β-catenin and osterix at the tissue to subcellular level in a coherent manner, and uncovered their spatio-temporal cooperation in postnatal bone development, thus providing evidence that they link skeletogenic growth and functional bone development.

CIZ/NMP4 is expressed in B16 melanoma and forms a positive feedback loop with RANKL to promote migration of the melanoma cells

Tumor metastasis to bone is a serious pathological situation that causes severe pain, and deterioration in locomoter function. However, the mechanisms underlying tumor metastasis is still incompletely understood. CIZ/NMP4 is a nucleocytoplasmic shuttling protein and its roles in tumor cells have not been known. We, therefore, hypothesized the role of CIZ/NMP4 in B16 melanoma cells that metastasize to bone. CIZ/NMP4 is expressed in B16 cells. The CIZ/NMP4 expression levels are correlated to the metastatic activity in divergent types of melanoma cells. Overexpression of CIZ/NMP4 increased B16 cell migration in Trans-well assay. Conversely, siRNA-based knockdown of CIZ/NMP4 suppressed migratory activity of these cells. As RANKL promotes metastasis of tumor cells in bone, we tested its effect on CIZ in melanoma cells. RANKL treatment enhanced CIZ/NMP4 expression. This increase of CIZ by RANKL promoted migration. Conversely, we identified CIZ/NMP4 binding site in the promoter of RANKL. Furthermore, luciferase assay indicated that CIZ/NMP4 overexpression enhanced RANKL promoter activities, revealing a positive feedback loop of CIZ/NMP4 and RANKL in melanoma. These observations indicate that CIZ/NMP4 is critical regulator of metastasis of melanoma cells.

Profilin1 regulates sternum development and endochondral bone formation

Bone development is a dynamic process that requires cell motility and morphological adaptation under the control of actin cytoskeleton. This actin cytoskeleton system is regulated by critical modulators including actin-binding proteins. Among them, profilin1 (Pfn1) is a key player to control actin fiber structure, and it is involved in a number of cellular activities such as migration. During the early phase of body development, skeletal stem cells and osteoblastic progenitor cells migrate to form initial rudiments for future skeletons. During this migration, these cells extend their process based on actin cytoskeletal rearrangement to locate themselves in an appropriate location within microenvironment. However, the role of Pfn1 in regulation of mesenchymal progenitor cells (MPCs) during skeletal development is incompletely understood. Here we examined the role of Pfn1 in skeletal development using a genetic ablation of Pfn1 in MPCs by using Prx1-Cre recombinase. We found that Pfn1 deficiency in MPCs caused complete cleft sternum. Notably, Pfn1-deficient mice exhibited an absence of trabecular bone in the marrow space of appendicular long bone. This phenotype is location-specific, as Pfn1 deficiency did not largely affect osteoblasts in cortical bone. Pfn1 deficiency also suppressed longitudinal growth of long bone. In vitro, Pfn1 deficiency induced retardation of osteoblastic cell migration. These observations revealed that Pfn1 is a critical molecule for the skeletal development, and this could be at least in part associated with the retardation of cell migration.

Abstract 2415: Phenotypic stabilization of mesenchymal-like cancer cells through mesenchymal-specific DNA hypermethylation

The epithelial-mesenchymal transition (EMT) plays a crucial role in normal and disease processes including tumor progression. In this study, we first classified epithelial-like and mesenchymal-like oral squamous cell carcinoma (OSCC) cell lines based on expression profiles of typical EMT-related genes using a panel of 18 OSCC cell lines. Then, we performed methylation-based and expression-based analyses of components of the Wnt signaling pathway, and identified WNT7A and WNT10A as genes silenced by mesenchymal-specific DNA hypermethylation in OSCCs. A significant association was revealed between some clinicopathologic findings and the DNA methylation status of WNT7A (Normal vs Tumor, P = 0.007; T1-2 vs T3-4, P = 0.040; I-III vs IV, P = 0.016) and WNT10A (N0-N1 vs N2-N3, P = 0.046) in the advanced stages of OSCC. Moreover, we found that E-cadherin expression in cancer cells may be positively regulated by WNT7A, whose expression is negatively regulated by mesenchymal-specific DNA hypermethylation or ZEB1 in mesenchymal-like OSCC cells. Our findings indicate that epithelial-specific gene silencing through mesenchymal-specific DNA hypermethylation may stabilize the phenotypic plasticity of cancer cells during EMT/MET.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 2415. doi:1538-7445.AM2012-2415

Abstract 4932: Exploration of EMT-related microRNAs using function-based screening with expression analysis of E-cadherin in Panc1 line

Recently, epithelial-mesenchymal transition (EMT) has been demonstrated to contribute to malignant transformation during cancer progression. To perform the function-based screening of EMT-related microRNAs (miRNAs), we first generated an in vitro model using a pancreatic cancer cell line, Panc1, in which a transcriptional reporter construct containing E-cadherin promoter region and a reporter gene, GFP, was transfected. After the selection of independent clones by the limiting dilution and the examination of GFP-upregulation in response to overexpression of ectopic miR-200b/a, we successfully established a stable transfectant clone, Panc1-EPG8. Then, we performed function-based screening with expression analysis of GFP in Panc1-EPG8 cells 4 days after ectopic transfection of 470 synthetic miRNAs. We further reexamined the expression level of E-cadherin after ectopic transfection with selected candidate miRNAs in Panc1-EPG8 cells by Western blotting and qRT-PCR, resulting in the identification of a novel miRNA as a candidate EMT-related miRNA. Our findings strongly suggest that this miRNA may play a crucial role during EMT in cancer progression.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 4932. doi:1538-7445.AM2012-4932

Poly(ethylene glycol) hydrogels cross-linked by hydrolyzable polyrotaxane containing hydroxyapatite particles as scaffolds for bone regeneration

Poly(ethylene glycol) (PEG) hydrogels cross-linked by a hydrolyzable polyrotaxane containing hydroxyapatite particles (PRX-HAp) were developed as scaffolds for bone regeneration. Five scaffolds with various composition of the polyrotaxane, PEG and HAp particles were prepared to examine cell adhesion in vitro using rat primary cultured osteoblast. Cells were observed to attach well on a PRX-HAp that have the same weight ratio of the polyrotaxane and HAp particles at 7 days after seeding. These results indicate that HAp particles are necessary for cell adhesion and survival, but a higher ratio of the particles is not suitable for cell adhesion. The composites of rat osteoblast and the PRX-HAp were implanted subcutaneously in syngeneic rats and harvested at 5 weeks after implantation. In histological analysis, osteoblast-like cells became arrayed along the surface of the PRX-HAp, and osteoid-like tissues were observed in the region between a queue of osteoblast-like cells and PRX-HAp. These images are similar to intramembranous ossification, and it is expected that bone regeneration occurs on the surface of the PRX-HAp. This study strongly suggests the great potential of the PRX-HAp as scaffolds for bone regeneration.

Clinical significance of lymphatic and blood vessel invasion in oral tongue squamous cell carcinomas

Although vascular invasion (VI) is recognized as an important predictor of lymph node metastasis and a significant prognostic factor in head and neck squamous cell carcinoma (HNSCC), there is currently no common definition for the pathological evaluation of VI status. We reviewed the medical records of 63 consecutive resected primary oral tongue SCCs (OTSCCs) without preoperative treatment between June 1999 and April 2008, and evaluated VI status by investigating lymphatic vessel invasion (LVI) and blood vessel invasion (BVI) by using immunohistochemistry (IHC) with monoclonal antibody D2-40 (D2-40) and Elastica van Gieson (EVG) staining, respectively. Subsequently, we analyzed their correlations with cervical lymph node metastasis and prognosis. LVI was found in 16 of the 63 tumors (25.4%) and BVI was in 32 tumors (50.8%). Univariate analysis revealed that the presence of LVI is statistically correlated with lymph node metastasis. Moreover, multivariate logistic regression analysis revealed that LVI is an independent risk factor of nodal metastasis (odds ratio=4.262, 95% confidence interval=1.262-14.397, p=0.020). In contrast, Kaplan-Meier survival analysis revealed that patients with BVI had a significantly shorter disease-free survival (DFS) and overall survival (OS) rates than those without BVI (68.6% versus 90.3%, p=0.028 and 68.6% versus 93.5%, p=0.013, respectively). The present study clearly demonstrated that LVI at primary OTSCC had significant correlation with lymph node metastasis, and that BVI was significantly associated with recurrence and poor prognosis. Evaluation of VI status, as LVI and BVI status separately, using IHC with D2-40 and EVG staining may be useful in predicting lymph node metastasis and poor prognosis in OTSCCs.

EGFR gene copy number alteration is a better prognostic indicator than protein overexpression in oral tongue squamous cell carcinomas

Although epidermal growth factor receptor (EGFR) is particularly important in the pathogenesis of head and neck squamous cell carcinomas (HNSCCs), conflicting data have been reported on the correlation between EGFR copy number and survival and the association between EGFR copy number and protein expression. Anatomical site of the tumour in HNSCCs may likely contribute to the discordance of the above points as EGFR expression may differ between the sub-sites of HNSCCs. Thus, in this study, we focused on oral tongue squamous cell carcinomas (OTSCCs). To investigate the association between EGFR copy number alteration and overexpression and to determine which is the more reliable prognostic indicator, Fluorescence in situ hybridisation (FISH) and immunohistochemical staining (IHC) were performed at a single institution on samples from 89 patients with OTSCCs undergoing surgery as the primary treatment modality. Thirty-two (36%) of 89 cases demonstrated an EGFR copy number alteration. EGFR protein expression was found in all 89 cases, of which 82.0% showed overexpression. No significant correlation was found between gene copy number and protein overexpression. Gene copy number alteration was significantly associated with reduced disease-free survival (P=0.048) and overall survival (P=0.001). Multivariate Cox proportional hazards analysis demonstrated that EGFR copy number increase was significantly correlated with overall survival (P=0.001). EGFR copy number status is a more reliable indicator than protein overexpression of the survival rate in OTSCCs. FISH analysis of the EGFR status is useful in predicting poor prognosis in OTSCCs.

Effect of the reclining position in patients after oral tumor surgery

OBJECTIVES

This study investigated the effects of reclining position on swallowing functions in the patients who had undergone surgery for oral tumors.

SUBJECTS AND METHODS

53 Patients after oral tumor surgery who had undergone the videofluoroscopic swallowing study in the sitting position and reclining position were sampled. We measured Oral transit time (OTT), Pharyngeal transit time (PTT), Penetration-Aspiration scale, Locating of the leading edge of bolus at swallow onset, Route of bolus transit and Transit velocity.

RESULTS

Laryngeal penetration and aspiration were less likely to occur in the reclining position. The mean OTT was significantly shorter in the reclining position than in the sitting position. The leading edge of bolus at swallow onset was significantly lower in the reclining position than in the sitting position. The bolus went along the posterior wall of the pharynx in more patients in the reclining position. The mean PTT and the transit velocity did not significantly differ between the reclining position and the sitting position.

CONCLUSION

This study suggested that, in patients after surgery on oral tumors, the reclining position is a useful posture to aid oral transit and to readily prevent aspiration and laryngeal penetration.

[A clinico-pathological study of 20 cases of Warthin's tumors of the parotid gland]

PURPOSE

The purpose of this study was to clarify the clinico-pathological findings of Warthin's tumors.

SUBJECTS AND METHODS

Twenty cases of Warthin's tumors treated at our clinic during the past 22 years and their medical charts and imaging films were reviewed.

RESULTS

Warthin's tumors occurred more frequently in middle-aged or elderly men than in women. Solitary tumors were significantly larger (p < 0.05) than multiple tumors. Warthin's tumors that accumulated 99mTc were significantly larger (p < 0.05) than those that did not. In addition, there was no difference in clinical findings between the two histopathologic types of Warthin's tumors.

CONCLUSION

The frequent occurrence of multiple Warthin's tumors indicated the importance of an accurate clinical and radiological examination of parotid glands, in order to detect possible multiple lesions prior to treatment.

Characterization of the radioresponse of human apical papilla-derived cells

Background

The purpose of this study was to characterize the radiobiological properties of stem/progenitor cells derived from apical papilla-derived cells (APDCs) compared to bulk APDCs.

Methods

APDCs were isolated from freshly extracted human third molars with immature apices. Multipotent spheres, which are thought to contain an enriched population of stem/progenitor cells, were formed from the APDCs, using a neurosphere culture technique. After γ-irradiation, papillary sphere-forming cells (PSFCs) and bulk APDCs were subjected to radiosensitivity and hard tissue-forming assays.

Results

Compared to bulk APDCs, the PSFCs exhibited a radioresistant phenotype and a higher capacity for DNA double strand break repair. Irradiation induced a significant increase in a senescence-like phenotype in both cell types. Neither type of cells exhibited a significant induction of apoptotic changes after 8 Gy of irradiation. Ability to form hard tissue in vivo was significantly decreased in PSFCs, but not in APDCs following 4 Gy of irradiation.

Conclusions

We demonstrated for the first time that stem/progenitor cells derived from APDCs exhibit a radioresistant phenotype; however, the hard tissue forming ability in vivo, but not bulk APDCs, was significantly reduced after irradiation.

Cell-printing and transfer technology applications for bone defects in mice

Bone regeneration therapy based on the delivery of osteogenic factors and/or cells has received a lot of attention in recent years since the discovery of pluripotent stem cells. We reported previously that the implantation of capillary networks engineered ex vivo by the use of cell-printing technology could improve blood perfusion. Here, we developed a new substrate prepared by coating glass with polyethylene glycol (PEG) to create a non-adhesive surface and subsequent photo-lithography to finely tune the adhesive property for efficient cell transfer. We examined the cell-transfer efficiency onto amniotic membrane and bone regenerative efficiency in murine calvarial bone defect. Cell transfer of KUSA-A1 cells (murine osteoblasts) to amniotic membrane was performed for 1 h using the substrates. Cell transfer using the substrate facilitated cell engraftment onto the amniotic membrane compared to that by direct cell inoculation. KUSA-A1 cells transferred onto the amniotic membrane were applied to critical-sized calvarial bone defects in mice. Micro-computed tomography (micro-CT) analysis showed rapid and effective bone formation by the cell-equipped amniotic membrane. These results indicate that the cell-printing and transfer technology used to create the cell-equipped amniotic membrane was beneficial for the cell delivery system. Our findings support the development of a biologically stable and effective bone regeneration therapy.

Comprehensive keratin profiling reveals different histopathogenesis of keratocystic odontogenic tumor and orthokeratinized odontogenic cyst

Keratocystic odontogenic tumor is a cystic lesion that behaves more aggressively than other jaw cysts. One of its characteristic histologic features is a parakeratinized uniform layer of lining epithelium. A jaw cyst lined with orthokeratinized epithelium is called an orthokeratinized odontogenic cyst. These keratinized jaw cysts are thought to be separate entities, although their histopathogenesis has not been fully assessed. To better understand these lesions, we performed comprehensive immunohistochemical profiling of the keratin expression of each. Orthokeratinized odontogenic cysts expressed keratin 1, keratin 2, keratin 10, and loricrin, suggesting differentiation toward normal epidermis. Keratocystic odontogenic tumors expressed keratin 4, keratin 13, keratin 17, and keratin 19, which is a unique expression pattern reminiscent of a mucosal squamous epithelium and an epithelial appendage. In neonatal rat tooth germ, cells strongly positive for keratin 17 and keratin 19 were observed, specifically in the dental lamina, implying the origin of keratocystic odontogenic tumor. GLI2, a downstream effector of hedgehog signaling, was significantly expressed in keratocystic odontogenic tumor and basal cell carcinoma, accompanied with robust expression of keratin 17, mammalian target of rapamycin, and BCL2. The expression of these GLI2- or keratin 17-related factors was not significantly observed in orthokeratinized odontogenic cysts. These findings provide evidence to support the viewpoint that keratocystic odontogenic tumor and orthokeratinized odontogenic cyst are separate entities, and furthermore suggest their characteristic histology, pathogenesis, and biological behaviors.

Prognostic utility of chromosomal instability detected by fluorescence in situ hybridization in fine-needle aspirates from oral squamous cell carcinomas

BACKGROUND

Although chromosomal instability (CIN) has been detected in many kinds of human malignancies by means of various methods, there is no practical assessment for small clinical specimens. In this study, we evaluated CIN in fine-needle aspiration (FNA) biopsied oral squamous cell carcinomas (SCCs) using fluorescence in situ hybridization (FISH) analysis, and investigated its prognostic significance.

METHODS

To evaluate CIN status of tumors, FISH with genomic probes for the centromeres of chromosomes 7, 9, and 11 was performed on specimens obtained by FNA from 77 patients with primary oral SCCs.

RESULTS

High-grade CIN (CIN3) was observed in 11.7% (9/77) of patients with oral SCCs and was associated significantly with reduced disease-free survival (p = .008) and overall survival (p = .003). Multivariate Cox proportional hazards analysis showed that CIN status was significantly correlated with disease-free survival (p = .035) and overall survival (p = .041).

CONCLUSION

Analysis of CIN status using FISH on FNA biopsy specimens may be useful in predicting of recurrence and poor prognosis in patients with oral SCCs.

Effective staining method with iodine for leukoplakia and lesions surrounding squamous cell carcinomas of the tongue assessed by colorimetric analysis

To determine whether staining with iodine solution provides an efficient criterion for determining the area of resection for the lesions surrounding squamous cell carcinoma (SCC) and leukoplakia of the tongue, we determined the optimum density of iodine solution and staining procedure and analyzed the color of lightly stained lesions (LSLs) in relation to the histopathologic findings. Sixty-five patients with SCC or leukoplakia of the tongue were divided into two groups: lesions stained with 3% Lugol solution and restained with either 5% Lugol solution (n=38) or 10% iodine glycerin (n=27). Among the lesions stained with 5% Lugol solution, significant differences were found in all color values. Color difference values (DeltaE*ab) using 3% and 5% Lugol solutions were significantly different between epithelial hyperplasia/mild epithelial dysplasia and moderate to severe dysplasia (P < 0.05). According to the evaluations of five clinicians in 46 LSLs, a distinctive boundary was most often obtained using 5% Lugol solution. These results suggest that the most effective method for obtaining a clear boundary and distinguishing moderate to severe dysplasia from mild or no epithelial dysplasia according to the measured color value was to stain with 3% followed by 5% Lugol solution.

Amphiregulin induces proliferative activities in osseous dysplasia

Human osseous dysplasia (OD) is a benign fibro-osseous neoplasm of periodontal ligament origin in which normal bone is replaced with fibrous connective tissue containing abnormal bone or cementum. However, cellular differentiation and proliferation in OD have not been fully elucidated. In vitro culture systems have distinct advantages for analytical studies. Therefore, we established immortalized cell lines (OD-1) from OD lesions of the jaw from an individual with gnathodiaphyseal dysplasia (GDD). We hypothesized that OD-1 had a characteristic growth mechanism different from that of mineralized-associated cells such as osteoblasts. To clarify the difference of gene expression patterns between OD-1 and osteoblasts, we compared the profiles of genes expressed in the 2 cell types by microarray analysis. We identified amphiregulin to be highly expressed in OD-1 compared with osteoblasts and gingival fibroblasts. OD-1 showed proliferative activities regulated in an autocrine manner by amphiregulin, and amphiregulin may play a significant role in the proliferation of OD.

Identification of PAK4 as a putative target gene for amplification within 19q13.12-q13.2 in oral squamous-cell carcinoma

Amplification of chromosomal DNA is thought to be one of the mechanisms activating cancer-related genes in tumors. To identify the most likely target for amplification in the region 19q13.12-q13.2, detected previously in SKN-3 cells by a genome-wide screening of DNA copy-number aberrations in a panel of oral squamous-cell carcinoma (OSCC) cell lines, we determined the extent of the amplicon, analyzed a panel of cell lines for the expression of candidate genes within the amplicon, and then evaluated growth-suppressive effects by knocking down genes of interest. Reported information about the function and/or expression of each gene, remarkable overexpression in SKN-3 cells and relatively frequent overexpression in additional OSCC lines compared with an immortalized normal oral epithelial cell line, and expression level-dependent proliferation-promoting activity led us to conclude that the p21-activated kinase 4 (PAK4) gene was the most likely target. An immunohistochemical analysis of primary tumors from 105 cases of head and neck SCC including 50 cases of OSCC demonstrated the overexpression of PAK4 to be significantly associated with a poorer prognosis. These findings reveal that the PAK4 overexpression through amplification or other mechanisms promotes the proliferation and/or survival of OSCC cells, and that PAK4 might be a good diagnostic and/or therapeutic target.

Osteoblastic bone formation is induced by using nanogel-crosslinking hydrogel as novel scaffold for bone growth factor

Bone regeneration for the defects in revision surgery of joint replacement is an increasingly important issue. To repair bone defects, bone cell activation by growth factors using synthetic resorbable scaffold is a useful and safe option. We examine the efficiency of nanogel-crosslinking hydrogel as a novel synthetic scaffold for BMP to stimulate osteoblasts and to induce bone formation. Cholesterol-bearing pullulan nanogel-crosslinking hydrogel (CHPA/Hydrogel) was used to deliver BMP. The CHPA hydrogel pellets were implanted in vivo. Single implantation of CHPA/hydrogel containing low amounts of BMP induced osteoblastic activation and new bone formation in vivo. Furthermore, nanogel in a disc shape established recruitment of osteoblastic cells that vigorously formed bone to heal the calvarial defects, which did not heal spontaneously without it. In conclusion, CHPA/hydrogel serves as an efficient and versatile scaffold for the stimulation of osteoblasts to form bone and to repair defects via delivery of BMP.

[Improvement of outcomes by primary treatment for temporomandibular disorders]

The aim of this study was to survey the current state of the temporomandibular joint disorder treatment in our clinic and to confirm the therapeutic outcomes. The subjects in this study were recruited from among the patients with temporomandibular disorders who attended the Temporomandibular Disorder Special Clinic, Department of Oral Surgery, Hitachi Yokohama Hospital during one year period from February 2007 to January 2008. A total of 100 consecutive outpatients diagnosed with temporomandibular disorders were selected for the study. Pain intensity and the degree to which daily function was limited before and after treatment were evaluated using the Visual Analogue Scale (VAS). The Beck Depression Inventory-II (BDI-II) score was evaluated simultaneously, and the correlation with changes in symptom was evaluated. The median (25th, 75th percentiles) of pain intensity (VAS value) before treated was 45 (25.0, 65.0) and the degree of limitation of daily function (VAS value) was 15 (0.0, 50.0). The median (25th, 75th percentiles) of pain intensity at 4 weeks after was 10 (0.0, 30.0), and significantly lower than that before treatment (p = 0.000). The degree of limitation of daily function was 0 (0.0, 10.0), also significantly lower than that before treatment (p = 0.000). The BDI-II score decreased from 8 (2.0, 11.8) before treatment to 5 (2.0, 11.0, p = 0.024) and showed no significant correlation with the improvement in outcomes by primary treatment for temporomandibular disorders.

An investigation of magnetic resonance imaging features in 14 patients with synovial chondromatosis of the temporomandibular joint

OBJECTIVES

To show the characteristic MRI features of synovial chondromatosis (SC) of the temporomandibular joint (TMJ).

METHODS

All patients with histologically proven SC of the TMJ who underwent MRI at our clinic were examined. In 14 patients (male-to-female ratio, 2:12; average age 46+/-14 years), clinical and conventional radiographic findings were reviewed. In addition, the MRI findings of articular disc and condyle position, shape and signal intensity of the joint spaces, and bone changes of surrounding structures were analysed.

RESULTS

The main symptoms were pain (in 93% of the patients) and limitation of mouth opening (64%). Two cases showed typical multiple calcifications around the TMJ on conventional radiography. On MRI, the disc position was normal in 12 (86%) patients and the condyle was inferiorly displaced in 9 (64%) patients. 11 (79%) patients showed enlargement of the joint space, with either a "dumbbell" shape or bulging. SC in the upper compartment showed various degrees of bone changes of the articular eminence and fossa. SC in the lower compartment showed concavity or hypertrophy of the condyle. The severity of the bone changes progressed with duration of symptoms.

CONCLUSIONS

About 0.3% of the patients complaining of TMJ pain and dysfunction were found to have SC. There was great variation in the MRI features of the TMJs with SC. More severe destruction of surrounding bone structures with features resembling a tumour were found in patients with a longer duration of symptoms.

Diagnostic accuracy of cone-beam CT in the assessment of mandibular invasion of lower gingival carcinoma: comparison with conventional panoramic radiography

PURPOSE

To evaluate the diagnostic accuracy of cone-beam CT in assessing mandibular invasion by lower gingival carcinoma and compare it with that of panoramic radiography.

PATIENTS AND METHODS

Fifty patients with squamous cell carcinoma of the lower gingiva who were examined by both panoramic radiography and cone-beam CT before surgery were included in this study. Five radiologists used a 6-point rating scale to independently evaluate cone-beam CT and panoramic images for the presence or absence of alveolar bone and mandibular canal involvement by tumor. Using the histopathogical findings as the gold standard, we calculated and compared the area under the receiver operating characteristic curve (Az value) and the sensitivity and specificity of the two imaging modalities.

RESULTS

In evaluations of both alveolar bone and mandibular canal involvement, the mean Az value for cone-beam CT (0.918 and 0.977, respectively) was significantly higher than that for panoramic radiography (0.793 and 0.872, respectively). The mean sensitivity for cone-beam CT (89% and 99%, respectively) was significantly higher than that for panoramic radiography (73% and 56%, respectively). There was no significant difference in the mean specificity. While cone-beam CT could provide high-resolution three-dimensional images, the image quality around the alveolar crest was often hampered by severe dental artifacts and image noise, resulting in difficulties in detecting subtle alveolar invasion.

CONCLUSION

Cone-beam CT was significantly superior to panoramic radiography in evaluating mandibular invasion by lower gingival carcinoma. Its diagnostic value in detecting subtle alveolar invasion, however, may be limited by severe dental artifacts and image noise.

JunD suppresses bone formation and contributes to low bone mass induced by estrogen depletion

JunD is an activator protein-1 (AP-1) component though its function in skeletal system is still not fully understood. To elucidate the role of JunD in the regulation of bone metabolism, we analyzed JunD-deficient mice. JunD deficiency significantly increased bone mass and trabecular number. This bone mass enhancement was due to JunD deficiency-induced increase in bone formation activities in vivo. Such augmentation of bone formation was associated with simultaneous increase in bone resorption while the former was dominant over the latter as accumulation of bone mass occurred in JunD-deficient mice. In a pathological condition relevant to postmenopausal osteoporosis, ovariectomy reduced bone mass in wild type (WT) mice as known before. Interestingly, JunD deficiency suppressed ovariectomy-induced increase in bone resorption and kept high bone mass. In addition, JunD deficiency also enhanced new bone formation after bone marrow ablation. Examination of molecular bases for these observations revealed that JunD deficiency enhanced expression levels of c-jun, fra-1, and fra-2 in bone in conjunction with elevated expression levels of runx2, type I collagen, and osteocalcin. Thus, JunD is involved in estrogen depletion-induced osteopenia via its action to suppress bone formation and to enhance bone resorption.

GITR ligand-costimulation activates effector and regulatory functions of CD4+ T cells

Engagement of glucocorticoid-induced TNFR-related protein (GITR) enables the costimulation of both CD25(-)CD4(+) effector (Teff) and CD25(+)CD4(+) regulatory (Treg) cells; however, the effects of GITR-costimulation on Treg function remain controversial. In this study, we examined the effects of GITR ligand (GITRL) binding on the respective functions of CD4(+) T cells. GITRL-P815 transfectants efficiently augmented anti-CD3-induced proliferation and cytokine production by Teff cells. Proliferation and IL-10 production in Treg were also enhanced by GITRL transfectants when exogenous IL-2 and stronger CD3 stimulation was provided. Concomitant GITRL-costimulation of Teff and Treg converted the anergic state of Treg into a proliferating state, maintaining and augmenting their function. Thus, GITRL-costimulation augments both effector and regulatory functions of CD4(+) T cells. Our results suggest that highly activated and increased ratios of Treg reverse the immune-enhancing effects of GITRL-costimulation in Teff, which may be problematic for therapeutic applications using strong GITR agonists.

Inhibitory effect of CT domain of CCN3/NOV on proliferation and differentiation of osteogenic mesenchymal stem cells, Kusa-A1

CCN3/NOV activates the Notch signal through the carboxyl terminal cysteine-rich (CT) domain. CCN3 transfection to Kusa-A1 inhibited osteogenic differentiation and cell proliferation, which is accompanied by upregulation of Hes/Hey, Notch downstream targets, and p21, a CDK inhibitor. Upregulation of Hes/Hey and p21 was abrogated by the deletion of CT domain. Anti-proliferative activity of CCN3 was also abrogated by CT domain deletion whereas anti-osteogenic activity was not completely abrogated. We found that CT domain-deleted CCN3 still possesses antagonistic effect on BMP-2. These results suggest that CCN3 employs Notch and BMP pathways in anti-osteogenic activity while it inhibits cell proliferation uniquely by Notch/p21 pathway.

Serum osteopontin, an enhancer of tumor metastasis to bone, promotes B16 melanoma cell migration

Tumor malignancy is associated with several features such as proliferation ability and frequency of metastasis. Since tumor metastasis shortens patients' lifetime, establishment of therapy for anti-metastasis is very important. Osteopontin (OPN), which abundantly expressed in bone matrix, is involved in cell adhesion, migration, extracellular matrix (ECM) invasion and cell proliferation via interaction with its receptor, that is, alphavbeta3 integrin. OPN is believed to be a positive regulator of tumor metastasis in vivo. However, how OPN regulates metastasis is largely unknown. Here, we explore the role of OPN in cell migration. Serum from wild-type mice induced cell migration of B16 melanoma cells, while serum from OPN-deficient mouse suppressed this event. The presence of recombinant OPN significantly enhanced cell migration compared to albumin containing medium. OPN-induced cell migration was suppressed by inhibiting the ERK/MAPK pathway indicating that OPN-induced cell migration depends on this pathway. Overexpression of OPN in these cancer cells per se promoted cell proliferation and tended to increase B16 cell migration suggesting that OPN promotes bone metastasis by playing dual roles both in host microenvironment and in tumor cell itself. In conclusion, the elevated OPN expression in host tissue and tumor cell itself promotes tumor cell migration reading to tumor metastasis, suggesting that neutralization of OPN-induced signal might be effective in suppression of tumor metastasis.

PRTFDC1, a possible tumor-suppressor gene, is frequently silenced in oral squamous-cell carcinomas by aberrant promoter hypermethylation

Array-based comparative genomic hybridization (array-CGH) has good potential for the high-throughput identification of genetic aberrations in cell genomes. In the course of a program to screen a panel of oral squamous-cell carcinoma (OSCC), cell lines for genomic copy-number aberrations by array-CGH using our in-house arrays, we identified a 3-Mb homozygous deletion at 10p12 in 1 of 18 cell lines (5.6%). Among seven genes located within this region, expression of PRTFDC1 mRNA was not detected in 50% (9/18) or decreased in 5.6% (1/18) of OSCC cell lines, but detected in normal oral epithelia and restored in gene-silenced OSCC cells without its homozygous loss after treatment with 5-aza-2'-deoxycytidine. Among 17 cell lines without a homozygous deletion, the hypermethylation of the PRTFDC1 CpG island, which showed promoter activity, was observed in all nine cell lines with no or reduced PRTFDC1 expression (52.9%). Methylation of this CpG island was also observed in primary OSCC tissues (8/47, 17.0%). In addition, restoration of PRTFDC1 in OSCC cells lacking its expression inhibited cell growth in colony-formation assays, whereas knockdown of PRTFDC1 expression in OSCC cells expressing the gene promoted cell growth. These results suggest that epigenetic silencing of PRTFDC1 by hypermethylation of the CpG island leads to a loss of PRTFDC1 function, which might be involved in squamous cell oral carcinogenesis.

Noninvasive quantitative assessment of oral tongue cancer by intraoral ultrasonography

BACKGROUND

To assess tissue characterization of oral tongue cancer and prediction of subclinical cervical lymph node metastasis, we investigated whether intraoral ultrasonography could be used in conjunction with a computer-aided diagnosis (CAD) system.

METHODS

The study population comprised 109 patients with presurgical, clinical T1N0 or T2N0 oral tongue squamous cell carcinoma who underwent partial glossectomy. All the patients were examined by preoperative intraoral and postoperative ex vivo ultrasonography. To evaluate the ultrasonic images quantitatively, ultrasonographic parameters from tumor contour features were computed by using the proposed CAD system. The imaging results were correlated with histopathologic findings.

RESULTS

Oral tongue cancer was clearly identified in all patients by intraoral ultrasonography. Ultrasonic images of oral tongue cancer reflected the histopathologic structures. Subclinical cervical lymph node metastasis was predicted by intraoral ultrasonography. In a logistic regression analysis using the proposed CAD system, the diagnostic sensitivity, specificity, and accuracy for prediction of subclinical lymph node metastasis were 87.2%, 84.3%, and 85.3%, respectively.

CONCLUSIONS

Intraoral ultrasonography in conjunction with the proposed CAD system allows tissue characterization and prediction of subclinical cervical lymph node metastasis.

A tumor necrosis factor receptor loop peptide mimic inhibits bone destruction to the same extent as anti-tumor necrosis factor monoclonal antibody in murine collagen-induced arthritis

OBJECTIVE

The cyclic peptide WP9QY (YCWSQYLCY) was designed to mimic the most critical tumor necrosis factor alpha (TNFalpha) recognition loop on TNF receptor I, and it prevents interactions of TNFalpha with its receptor. We undertook this study to compare the effects of the WP9QY peptide on collagen-induced arthritis (CIA) in mice with those of anti-TNFalpha monoclonal antibody.

METHODS

CIA was induced by primary and secondary immunizations. Osmotic minipumps were implanted in the backs of all mice on the day of the booster injection (day 21), and vehicle, anti-TNF antibody (4 mg/kg/day), or WP9QY peptide (2 mg/kg/day or 4 mg/kg/day) was continuously infused until the mice were killed (day 40). Thereafter, clinical, radiographic, and histologic assessments were performed.

RESULTS

WP9QY treatment inhibited CIA-induced increases in the arthritis score, but onset of disease was not delayed by the peptide. The inhibitory effect of WP9QY on inflammation was definitely weaker than that of anti-TNF antibody. Microfocal computed tomography analyses, however, revealed that WP9QY blocked CIA-induced bone destruction at the knee joints to the same extent as did anti-TNF antibody. In addition, WP9QY inhibited synovial pannus infiltration and reduced osteoclast number. Furthermore, inhibition of CIA-induced systemic bone loss by WP9QY was more apparent than that by anti-TNF antibody.

CONCLUSION

The TNFalpha antagonist WP9QY would be a useful template for the development of small molecular inhibitors to prevent both inflammatory bone destruction and systemic bone loss in rheumatoid arthritis.