Short-Term Stability After Segmental Le Fort I Maxillary Impaction Surgery With Mandibular Autorotation in Seven High-Angle Class II Patients: A Case Series.

PURPOSE: To retrospectively evaluate skeletal stability after Le Fort I maxillary impaction surgery and mandibular autorotation without bilateral sagittal split osteotomy (BSSO) in high-angle class II patients. MATERIALS AND METHODS: Seven female high-angle class II patients who underwent maxillary impaction surgery and mandibular autorotation without bilateral sagittal split osteotomy were included in this study. Surgical changes and relapse were measured on lateral cephalograms taken preoperatively and at 1 month, 6 months and 1 year postoperatively. RESULTS: The horizontal movement of the maxilla at point A was 5.8 ±â€Š3.3 mm backward, and the upward movement at the posterior nasal spine was 3.3 ±â€Š1.4 mm. The mean horizontal change at point A during the 1-year follow-up period was 0.1 ±â€Š0.2 mm, and the vertical change at posterior nasal spine was 0.2 ±â€Š1.3 mm, which were not statistically significant. The horizontal surgical change at point B was 4.0 ±â€Š1.8 mm forward and the vertical surgical change at point B was 4.7 ±â€Š1.8 mm upward. Postoperative relapse was 10.9% and 13.7% in the horizontal and vertical directions, respectively. CONCLUSIONS: Le Fort I maxillary impaction surgery with mandibular autorotation may be 1 of the suitable procedures for high-angle class II patients.

Co-expression of EGFR and MET has a synergistic effect on the prognosis of patients with oral squamous cell carcinoma.

BACKGROUND: This study aimed to elucidate the correlation between gene amplification, protein expression of receptor tyrosine kinase, and prognosis of patients with oral squamous cell carcinoma (OSCC) using immunohistochemistry (IHC) and next-generation sequencing data. METHODS: We evaluated data pertaining to 208 patients with OSCC using IHC for epidermal growth factor receptor (EGFR) and mesenchymal-epithelial transition factor (MET). RESULTS: High expressions of EGFR and MET were detected in 60 and 41 patients, respectively. We evaluated the association of clinicopathological variables with high expressions of EGFR and/or MET. Distant metastasis was found in 9 of 41 patients (22.0%) and 6 of 15 patients (40.0%) with high expression of MET and high co-expressions of EGFR and MET, respectively; statistically significant differences were detected in both high expression of MET (P = .003) and high co-expressions of EGFR and MET (P = 3.41 × 10-5 ). The cumulative 5-year survival rate of patients with high and low expressions of EGFR or MET was approximately 65% and 85%, respectively. Conversely, among cases with high expressions of EGFR or MET, there was no additional decrease in the survival rate of patients harboring TP53 mutations. Moreover, the survival rate of patients with high co-expression of both EGFR and MET was very poor (22.0%) (P < 1.0 × 10-9 ). CONCLUSION: Our findings suggest that evaluation of protein expressions of EGFR and MET may facilitate prognostic assessment of patients with OSCC; in addition, patients with OSCC should be screened for enrollment in clinical trials of combination therapy with EGFR and MET inhibitors.

Loss of Notch1 predisposes oro-esophageal epithelium to tumorigenesis.

Notch signaling functions in diverse developmental and homeostatic processes, including stem cell self-renewal and cell fate determination. Notch1-inactivating mutations are frequently detected in skin and oro-esophageal cancers, suggesting a role for Notch1 as a tumor suppressor. Here, we clarify the contribution of Notch1 deficiency to oro-esophageal tumorigenesis using a physiological experimental model. Tongue and esophageal tumors induced in mice by 4-nitroquinoline-1-oxide (4-NQO) showed pathophysiological similarities to human tumors, including decreased Notch1 expression in the basal cells. We created mutant mice (N1cKO), in which the Notch1 gene was disrupted specifically in the squamous epithelium. The epithelium formed normally in N1cKO mice, and although multiple skin tumors were detected at 65 weeks, no tumors developed in the tongue and esophagus. However, 4-NQO-induced tumorigenesis assays revealed that tumor onset occurred earlier in N1cKO mice than in wild-type littermates, and the tumors arose preferentially from the Notch1-negative epithelium, indicating the tumor susceptibility of Notch1-deficient epithelium. Notch1 regulates the expression of TERT, and age-related telomere erosion was more rapid in Notch1-deficient basal cells. Our results indicated that although Notch1 deficiency had little effect on squamous epithelium formation, it predisposed the affected epithelium to tumor development, at least in part through accelerated telomere erosion.

The Japanese Society of Pathology Guidelines on the handling of pathological tissue samples for genomic research: Standard operating procedures based on empirical analyses.

Genome research using appropriately collected pathological tissue samples is expected to yield breakthroughs in the development of biomarkers and identification of therapeutic targets for diseases such as cancers. In this connection, the Japanese Society of Pathology (JSP) has developed "The JSP Guidelines on the Handling of Pathological Tissue Samples for Genomic Research" based on an abundance of data from empirical analyses of tissue samples collected and stored under various conditions. Tissue samples should be collected from appropriate sites within surgically resected specimens, without disturbing the features on which pathological diagnosis is based, while avoiding bleeding or necrotic foci. They should be collected as soon as possible after resection: at the latest within about 3 h of storage at 4°C. Preferably, snap-frozen samples should be stored in liquid nitrogen (about -180°C) until use. When intending to use genomic DNA extracted from formalin-fixed paraffin-embedded tissue, 10% neutral buffered formalin should be used. Insufficient fixation and overfixation must both be avoided. We hope that pathologists, clinicians, clinical laboratory technicians and biobank operators will come to master the handling of pathological tissue samples based on the standard operating procedures in these Guidelines to yield results that will assist in the realization of genomic medicine.

Receptor tyrosine kinase amplification is predictive of distant metastasis in patients with oral squamous cell carcinoma.

This study aimed to clarify the genomic factors associated with the diagnosis and prognosis of oral squamous cell carcinoma via next-generation sequencing. We evaluated data from 220 cases of oral squamous cell carcinoma. Genomic DNA was eluted using formalin-fixed, paraffin-embedded samples, and targeted resequencing of 50 cancer-related genes was performed. In total, 311 somatic mutations were detected in 220 patients, consisting of 68 synonymous mutations and 243 non-synonymous mutations. Genes carrying mutations included TP53, CDKN2A, and PIK3CA in 79 (35.9%), 35 (15.9%), and 19 patients (8.6%), respectively. Copy number analysis detected amplification of PIK3CA and AKT1 in 38 (17.3%) and 11 patients (5.0%), respectively. Amplification of receptor tyrosine kinases was found in 37 patients (16.8%). Distant metastasis was noted in nine of 37 patients (24%) with receptor tyrosine kinase amplification, accounting for 43% of the 21 cases of distant metastasis. The cumulative 5-year survival rate was 64.6% in the receptor tyrosine kinase amplification group vs 85.2% in the no receptor tyrosine kinase amplification group. Moreover, we identified significantly poorer prognosis in the TP53 mutation/receptor tyrosine kinase amplification group, for which the cumulative 5-year survival rate was 41.6%. In conclusion, the results of this study demonstrated that receptor tyrosine kinase amplification is a prognostic factor for distant metastasis of oral squamous cell carcinoma, indicating the necessity of using next-generation sequencing in clinical sequencing.

LAMC2 is a predictive marker for the malignant progression of leukoplakia.

BACKGROUND: LAMC2 plays an important role in cancer invasion. The aim of this study was to (i) compare the immunoexpression of LAMC2 in different stages of oral squamous cell carcinoma (OSCC), early and advanced, and (ii) to evaluate LAMC2 as a marker of malignant transformation in leukoplakia. MATERIALS AND METHODS: The expression of LAMC2 was examined by immunohistochemistry in 50 surgical specimens of advanced OSCC assembled as tissue microarrays, and by cDNA microarray in 43 surgical specimens of advanced OSCC. LAMC2 expression was further examined in 39 surgical specimens of early OSCC and in 93 incisional biopsy specimens of leukoplakia of the tongue, which exhibited epithelial dysplasia. The relationship of LAMC2 expression score with clinico-pathological characteristics was analyzed. RESULTS: LAMC2 was remarkably upregulated in OSCC at the cancer-stroma interface. The grade of LAMC2 expression was significantly associated with the pattern and depth of invasion of OSCC. Foci of LAMC2-positive cells were observed in some cases of leukoplakia. The number and size of LAMC2-positive foci were significantly associated with the grade of dysplasia. The presence of LAMC2-positive foci was a significant predictive factor for the malignant progression of leukoplakia. LAMC2-positive leukoplakia had an approximately 11-fold increased risk of malignancy compared with LAMC2-negative leukoplakia. CONCLUSIONS: The results of this study highlight the value of LAMC2 as a marker of cancer invasion. LAMC2-positive foci in leukoplakia suggest an imminent risk of cancer. LAMC2 immunostaining is expected to contribute to a more precise assessment of the malignancy of leukoplakia.

THBS1 is induced by TGFB1 in the cancer stroma and promotes invasion of oral squamous cell carcinoma.

BACKGROUND: THBS1 (thrombospondin-1) is the extracellular matrix (ECM) protein that affects diverse cellular activities. It constitutes the tumor stroma, but the role of THBS1 in oral squamous cell carcinoma (OSCC) development is unclear. The aim of this study was to clarify the relevance of THBS1 in the pathogenesis of OSCC. MATERIALS AND METHODS: The expression of THBS1 was examined in 44 OSCC by immunohistochemical analysis and in 43 OSCC by cDNA microarray analysis. Cell culture experiments were conducted using human OSCC cell lines HSC3 and HO1N1 and mouse fibroblast ST2 cells to examine the effect of TGFB1 on THBS1 expression, and the effect of THBS1 on cellular behaviors. RESULTS: THBS1 was specifically induced in the tumor microenvironment of OSCC. THBS1 appeared to be produced mainly by the stromal cells, but also by OSCC cells. TGFB1 stimulated THBS1 expression in ST2, primary fibroblasts, and the OSCC cells. THBS1 promoted migration and invasion of HSC3 and HO1N1 in transwell migration assays. THBS1 stimulated the expression of MMP3 (matrix metalloprotease 3), MMP9, MMP11, and MMP13 in ST2 cells and MMP3, MMP11, and MMP13 in HO1N1 cells. The RGD peptide suppressed the THBS1-stimulated migration and upregulation of MMP11 and MMP13. CONCLUSIONS: THBS1 is a tumor-specific ECM protein that is induced by TGFB1 and promotes migration of cancer cells and stimulates the expression of MMPs partly through the integrin signaling, thereby favoring OSCC invasion.

NF1 with 47,XYY mosaicism diagnosed by mandibular neurofibromas.

Neurofibromatosis type 1 (NF1) is an autosomal dominant nevus disease characterized by multiple manifestations, primarily café-au-lait macules and neurofibromas. Here, we present the case of an NF1 patient with 47,XYY mosaicism whose diagnosis was prompted by café-au-lait macules on the skin and mandibular neurofibromas. Targeted next-generation sequencing of the patient's blood sample revealed a novel frameshift mutation in NF1 (NM_000267.3:c.6832dupA:p.Thr2278Asnfs*8) that is considered a pathogenic variant.

Clinical, genomic and immune microenvironmental determinants of nivolumab response in head and neck squamous cell carcinoma.

Background: In view of improving biomarkers predicting the efficacy of immunotherapy for head and neck squamous cell carcinoma (R/M HNSCC), this multicenter retrospective study aimed to identify clinical, tumor microenvironmental, and genomic factors that are related to therapeutic response to the anti- Programmed cell death protein 1 (PD-1) antibody, nivolumab, in patients with R/M HNSCC. Methods: The study compared 53 responders and 47 non-responders, analyzing formalin-fixed paraffin-embedded samples using 14-marker multiplex immunohistochemistry and targeted gene sequencing. Results: Of 100 patients included, responders had significantly lower smoking and alcohol index, higher incidence of immune related adverse events, and higher PD-1 ligand (PD-L1) expression in immune cells as well as PD-L1 combined positive score (CPS) than non-responders. The frequency of natural killer cells was associated with nivolumab response in patients with prior cetuximab use, but not in cetuximab-naïve status. Age-stratified analysis showed nivolumab response was linked to high CPS and lymphoid-inflamed profiles in patients aged ≥ 65. In contrast, lower NLR in peripheral blood counts was associated with response in patients aged < 65. Notably, TP53 mutation-positive group had lower CPS and T cell densities, suggesting an immune-excluded microenvironment. Patients with altered tumor suppressor gene pathways, including TP53, CDKN2A, and SMAD4 mutations, had lower CPS, higher smoking index, and were associated with poor responses. Conclusion: Nivolumab treatment efficacy in HNSCC is influenced by a combination of clinical factors, age, prior treatment, immune environmental characteristics, and gene mutation profiles.

Clinical manifestations and treatment for keratocystic odontogenic tumors associated with nevoid basal cell carcinoma syndrome: a study in 25 Japanese patients.

BACKGROUND: Nevoid basal cell carcinoma syndrome (NBCCS) is an autosomal dominant disorder and is characterized by tumorigenesis and physical deformity. Keratocystic odontogenic tumors (KCOTs) of the jaws are a common manifestation of this syndrome. This study involved a pooled analysis of Japanese individuals with NBCCS and was performed with the aim of analyzing the clinical features of NBCCS and the patterns of occurrence and recurrence of KCOTs in Japanese individuals. METHODS: This study included 25 patients. The relative frequencies of the major symptoms in these patients were compared with those reported in the literature. We also investigated 11 patients with KCOTs (40 lesions) initially treated at Tokyo Medical and Dental University. RESULTS: KCOTs (100%) and palmar and/or plantar pits (n = 19; 76.0%) were the most frequently observed manifestations. Eleven patients (44.0%) had a radiologically confirmed rib anomaly. Nineteen patients (76.0%) had a family history of the syndrome within first-degree relatives. Japanese patients had a relatively low frequency of basal cell carcinoma (n = 7; 28.0%) and falx calcification (n = 7; 28.0%) compared with that reported in other populations. Twelve of the total 40 KCOTs (30.0%) that were followed up for 6 months or more recurred. All recurrent cases had undergone conservative treatment, whereas no recurrences occurred in cases that had undergone radical treatment. CONCLUSIONS: Recurrence of KCOTs associated with NBCCS is frequently encountered, and further investigations are required to confirm the optimal treatment that will ensure a complete cure improving the patient's quality of life.

[Case of pyogenic spondylitis and epidural abscess after chemoradiotherapy for hypopharyngeal cancer].

Osteomyelitis is one of the most severe late complications of radiation therapy. The condition can arise from osteoradionecrosis and can be fatal if it occurrs in vertebrae. A 71-year-old woman, who had undergone chemoradiotherapy for hypopharyngeal cancer 6 months previously, presented with severe neck pain. An MRI examination revealed pyogenic spondylitis and an epidural abscess of the neck. Neurological disturbance in the extremities developed despite the administration of antibiotics for 5 days. Drainage and a laminectomy were performed to control the infection and to relieve spinal cord compression. The patient had no postoperative complications at 15 months after surgery. Previous case reports of osteomyelitis and epidural abscess following radiation therapy for head and neck cancer with surgical treatment tended to have a good clinical course. Severe neck pain and a limitation in the range of motion of the neck are considered to be serious clinical features of osteomyelitis. Since infection in the necrotic mucosa leads to pyogenic spondylitis, a repeated cultivation survey of the mucosa is nessesary for adequate antibiotics therapy. For osteomyelitis and epidural abscess following radiation therapy, immediate specific surgical treatment of the involved region is strongly suggested if antibiotics are not effective or spinal cord compression develops.

Truncal Blocks for Emergency Laparotomy in a High-Risk Patient: A Case Report and Literature Review.

In critically ill patients undergoing laparotomy, both general anesthesia (GA) and central neuraxial block (CNB) may pose significant risks. Peripheral truncal blocks have been reported to provide effective postoperative analgesia following laparotomy. However, there are a limited number of reports describing this technique as surgical anesthesia for laparotomy. An 86-year-old man with non-specific interstitial pneumonia under home oxygen therapy and aortic valve stenosis was diagnosed with an incarcerated inguinal hernia. Because of these comorbidities, both GA and CNB were considered relatively contraindicated. Thus, we chose an ultrasound-guided transverse abdominis plane block and ilioinguinal/iliohypogastric block supplemented with neuroleptanesthesia as surgical anesthesia for emergency laparotomy. The surgery was uneventful using this technique. Truncal blocks supplemented with titrated intravenous sedatives/analgesics could be an alternative in high-risk patients undergoing laparotomy in whom both GA and CNB are considered relatively contraindicated.

Effects of Climate Conditions before Harvest Date on Edamame Metabolome.

Edamame is a green soybean that is rich in nutrients. Boiled edamame has been traditionally used for food in the East Asia region. It was known among farmers that conditions, such as temperature and climate on the day of harvest, affect the quality of edamame. Large-scale farmers harvest edamame on multiple days in the same year; however, the quality of edamame varies from day to day due to variations in climate conditions. In this study, we harvested edamame over several days between 2013 and 2018, obtained the climate conditions on the harvest date, and performed metabolome analysis using capillary electrophoresis mass spectrometry. To clarify the correlation between climate conditions before the harvest date and edamame components, comparative analyses of the obtained meteorological and metabolomic data were conducted. We found positive and negative correlations between the sunshine duration and average temperature, and the amounts of some edamame components. Furthermore, correlations were observed between the annual fluctuations in climate conditions and edamame components. Our findings suggest that the climate conditions before the date of harvesting are closely related to edamame quality.

Reduction of NOTCH1 expression pertains to maturation abnormalities of keratinocytes in squamous neoplasms.

Notch is a transmembrane receptor functioning in the determination of cell fate. Abnormal Notch signaling promotes tumor development, showing either oncogenic or tumor suppressive activity. The uncertainty about the exact role of Notch signaling, partially, stems from inconsistencies in descriptions of Notch expression in human cancers. Here, we clarified basal-cell dominant expression of NOTCH1 in squamous epithelium. NOTCH1 was downregulated in squamous neoplasms of oral mucosa, esophagus and uterine cervix, compared with the normal basal cells, although the expression tended to be retained in cervical lesions. NOTCH1 downregulation was observed even in precancers, and there was little difference between cancers and high-grade precancerous lesions, suggesting its minor contribution to cancer-specific events such as invasion. In culture experiments, reduction of NOTCH1 expression resulted in downregulation of keratin 13 and keratin 15, and upregulation of keratin 17, and NOTCH1 knockdown cells formed a dysplastic stratified epithelium mimicking a precancerous lesion. The NOTCH1 downregulation and the concomitant alterations of those keratin expressions were confirmed in the squamous neoplasms both by immunohistochemical and cDNA microarray analyses. Our data indicate that reduction of NOTCH1 expression directs the basal cells to cease terminal differentiation and to form an immature epithelium, thereby playing a major role in the histopathogenesis of epithelial dysplasia. Furthermore, downregulation of NOTCH1 expression seems to be an inherent mechanism for switching the epithelium from a normal and mature state to an activated and immature state, suggesting its essential role in maintaining the epithelial integrity.

Recurrence patterns of oral leukoplakia after curative surgical resection: important factors that predict the risk of recurrence and malignancy.

BACKGROUND: Oral leukoplakia can be treated using a variety of treatment procedures; however, the lesions recur in many cases irrespective of the treatment procedure used. The rate of recurrence was from 7.7% to 38.1%. This study aims to identify the important factors that can lower the risk of recurrence of oral leukoplakia treated by curative surgical resection. METHODS: The clinical records of 52 patients with oral leukoplakia (53 lesions) who underwent curative surgical resection between 2004 and 2009 were retrospectively analyzed for the rate of recurrence, clinical outcome, epithelial dysplasia, lesion location, and resection margins. RESULTS: The recurrence rate following curative surgical resection was 15.1%, with the most common site being the gingiva. Malignant transformation occurred in a single patient (1.9%). Minimal resection margins (<3 mm) were observed in many patients with recurrent disease, and recurrence was more likely in cases with positive margins (epithelial abnormalities at the resection margins) than in those with negative margins. There was no significant association between recurrence and the degree of epithelial dysplasia. CONCLUSIONS: Our data suggest that surgical resection of oral leukoplakia is curative only if all areas of epithelial abnormalities are identified and resected. Moreover, an adequate resection margin may reduce the risk of recurrence.

Quantitative diffusion-weighted magnetic resonance imaging as a powerful adjunct to fine needle aspiration cytology for assessment of thyroid nodules.

OBJECTIVES: The purpose of this study was to assess the value of the apparent diffusion coefficient (ADC) in the differential diagnosis between benign and malignant thyroid nodules, particularly those found to have indeterminate cytology with fine needle aspiration (FNA). METHODS: Thirty-eight patients with 42 thyroid nodules underwent neck magnetic resonance imaging consisting of T1-, T2-, and diffusion-weighted imaging. The final diagnosis of all nodules was confirmed by surgery, revealing 23 with benign and 19 with malignant lesions. Preoperative FNA cytology was performed in 38 of 42 nodules, including 15 of indeterminate cytology. The mean ADC values in benign and malignant groups were compared. RESULTS: There was a significant difference between mean ADC values in benign and malignant nodules and between mean ADC in benign and malignant nodules of indeterminate cytology. A cutoff value for malignant nodules of 1.60 × 10(-3) mm(2)/s yielded sensitivity, specificity, and accuracy of 94.73%, 82.60%, and 88.09%, respectively. CONCLUSION: The present study revealed that ADC measurements could potentially quantitatively differentiate between benign and malignant thyroid nodules, even those of indeterminate cytology. We propose that diffusion-weighted imaging evaluation should be used for the assessment of thyroid nodules in addition to FNA cytology.

Coexpression of SGLT1 and EGFR is associated with tumor differentiation in oral squamous cell carcinoma.

Overexpression of epidermal growth factor receptor (EGFR) is associated with resistance to chemotherapy and radiotherapy, advanced tumor stage, invasion, metastasis and poor prognosis in malignant tumors. EGFR, therefore, has been an attractive molecular target for chemotherapy. However, the results of clinical studies using inhibitors of its kinase activity have not been promising because the response rates were at most 20%. Sodium-glucose co-transporter 1 (SGLT1) is a membrane protein that mediates the transport of glucose across cellular membranes. EGFR physically associates with and stabilizes SGLT1 to promote glucose uptake into cancer cells through a kinase-independent process. The purpose of this study was to investigate the coexpression of SGLT1 and EGFR and its relationships with clinicopathological features in oral squamous cell carcinoma (OSCC). SGLT1 and EGFR were detected in all OSCC cell lines, and the expression levels of SGLT1 were significantly correlated with those of EGFR. Pearson product-moment correlation coefficient of SGLT1 and EGFR was 0.89 (P = 0.016). The immunohistochemical study using the surgical specimens in 52 patients with tongue SCC also showed a significant correlation between SGLT1 and EGFR. Moreover, SGLT1/EGFR expression was inversely related to tumor differentiation among the 5 clinicopathological factors (P = 0.004). SGLT1/EGFR coexpression might be required in the de-differentiation of OSCC, but further study is needed to clarify the implication of these proteins in the manifestation of malignancy and clinical significance.

Changes in the condylar volume and skeletal relapse following orthognathic surgery in patients with dentofacial deformity: A retrospective study.

OBJECTIVE: To evaluate the relationship between the changes in condylar volume and maxillofacial skeletal morphology according to sex as well as the relationship between condylar volume reduction and skeletal relapse in patients who underwent orthognathic surgery. METHODS: Ninety-five patients were categorized into skeletal Class III, Class II, and facial asymmetry groups. Computed tomography scans taken preoperatively and at 1 year postoperatively were used for quantitative measurement. RESULTS: Postoperative condylar volume was reduced in both the Class II group and the deviated side of the asymmetry group. Both female and Class II deformity were significant predictors of postoperative reduction in the condylar volume. There was a significant correlation between skeletal relapse and postoperative change in condylar volume in the Class II group. CONCLUSION: Postoperative condylar resorption may be associated with preoperative maxillofacial skeletal morphology and sex and also with skeletal relapse in the Class II group.

Roles of interleukin-6 and parathyroid hormone-related peptide in osteoclast formation associated with oral cancers: significance of interleukin-6 synthesized by stromal cells in response to cancer cells.

We investigated the roles of interleukin-6 (IL-6) and parathyroid hormone-related peptide (PTHrP) in oral squamous cell carcinoma (OSCC)-induced osteoclast formation. Microarray analyses performed on 43 human OSCC specimens revealed that many of the specimens overexpressed PTHrP mRNA, but a few overexpressed IL-6 mRNA. Immunohistochemical analysis revealed that IL-6 was expressed not only in cancer cells but also in fibroblasts and osteoclasts at the tumor-bone interface. Many of the IL-6-positive cells coexpressed vimentin. Conditioned medium (CM) derived from the culture of oral cancer cell lines (BHY, Ca9-22, HSC3, and HO1-u-1) stimulated Rankl expression in stromal cells and osteoclast formation. Antibodies against both human PTHrP and mouse IL-6 receptor suppressed Rankl in ST2 cells and osteoclast formation induced by CM from BHY and Ca9-22, although the inhibitory effects of IL6 antibody were greater than those of PTHrP antibody. CM derived from all of the OSCC cell lines effectively induced IL-6 expression in stromal cells, and the induction was partially blocked by anti-PTHrP antibody. Xenografts of HSC3 cells onto the periosteal region of the parietal bone in athymic mice presented histology and expression profiles of RANKL and IL-6 similar to those observed in bone-invasive human OSCC specimens. These results indicate that OSCC provides a suitable microenvironment for osteoclast formation not only by producing IL-6 and PTHrP but also by stimulating stromal cells to synthesize IL-6.

Down-regulation of keratin 4 and keratin 13 expression in oral squamous cell carcinoma and epithelial dysplasia: a clue for histopathogenesis.

AIMS: This study aimed to identify relevant keratin subtypes that may associate with the pathogenesis of oral epithelial neoplasms. METHODS AND RESULTS: Expression of all the keratin subtypes was examined by cDNA microarray analysis of 43 oral squamous cell carcinoma (OSCC) cases. Immunohistochemical expression of the major keratins was examined in 100 OSCC and oral epithelial dysplasia (OED) cases. Many changes in keratin expression were observed and, significantly, consistent down-regulation of keratin 4 (K4) and K13 expression was observed. Aberrant expression of K4 and K13 was associated with morphological changes in the affected oral epithelium. Experiments with cell cultures transfected with various keratin subtypes suggested that alterations in keratin subtype expression can cause changes in cell shape and movement. CONCLUSIONS: Aberrant expression of K4 and K13, which are the dominant pair of differentiation-related keratins in oral keratinocytes, indicates dysregulation of epithelial differentiation in OSCC and OED. These keratins, especially K4, may be useful for pathological diagnosis. We propose that the aberrant expression of K4 and K13 and concomitant up-regulation of the other keratins may be one of the causative factors for morphological alterations in the affected epithelium.