Hideaki Chazono

miR-489 is a tumour-suppressive miRNA target PTPN11 in hypopharyngeal squamous cell carcinoma (HSCC)

Background:Hypopharyngeal squamous cell carcinoma (HSCC) is an aggressive malignancy with one of the worst prognoses among all head and neck cancers. Greater understanding of the pertinent molecular oncogenic pathways could help improve diagnosis, therapy, and prevention of this disease. The aim of this study was to identify tumour-suppressive microRNAs (miRNAs), based on miRNA expression signatures from clinical HSCC specimens, and to predict their biological target genes.Methods:Expression levels of 365 human mature miRNAs from 10 HSCC clinical samples were screened using stem-loop real-time quantitative PCR. Downregulated miRNAs were used in cell proliferation assays to identify a tumour-suppressive miRNA. Genome-wide gene expression analyses were then performed to identify the target genes of the tumour-suppressive miRNA.Results:Expression analysis identified 11 upregulated and 31 downregulated miRNAs. Gain-of-function analysis of the downregulated miRNAs revealed that miR-489 inhibited cell growth in all head and neck cancer cell lines examined. The gene PTPN11 coding for a cytoplasmic protein tyrosine phosphatase containing two Src Homology 2 domains was identified as a miR-489-targeted gene. Knockdown of PTPN11 resulted in the inhibition of cell proliferation in head and neck SCC cells.Conclusion:Identification of the tumour-suppressive miRNA miR-489 and its target, PTPN11, might provide new insights into the underlying molecular mechanisms of HSCC.

Migration of Tumor Antigen-Pulsed Dendritic Cells After Mucosal Administration in the Human Upper Respiratory Tract

Tumor-specific peptide-pulsed dendritic cells (DC) were administered via different routes to a group of patients with head and neck cancers. The migration and homing patterns of such antigen-stimulated cells was carefully studied employing single photon emission computed tomography (SPECT). The DC administered directly into the nasal submucosa quickly migrated very rapidly to the regional neck lymph nodes in the neck. However, after inoculation of the cells into the palatine tonsils, the DCs remained close to the site of administration and did not migrate to the regional lymph nodes or to other mucosal regions. After nasal submucosal administration of the DC, tumor-antigen-specific cytotoxic T cells were detected in the ipsilaterals but not in the contra lateral lymph nodes. These results suggest that after antigen processing, the regional lymph nodes serve as inductive sites for development of mucosal immune responses and for induction of memory cells during the local immunological responses in the nasopharyngeal-associated lymphoid tissue in man.

The Influence of Environmental Exposure to Formaldehyde in Nasal Mucosa of Medical Students during Cadaver Dissection

BACKGROUND Environmental exposure to formaldehyde is commonly associated with clinical symptoms such as mucosal irritation and olfactory disorders. However, the impact of such exposure on the development of mucosal inflammation and its outcome has not been carefully evaluated. METHODS The observational non-comparative study was planned. The study population consisted of group of 41 medical students who had signed up for a cadaver dissection course as part of their gross anatomy teaching at the school of medicine Chiba University in Japan. During such dissection course, the students are exposed to variable levels of environmental formaldehyde routinely employed for the preservation the cadavers. The subjects were evaluated by a detailed medical examination. We measured their serum IgE levels. In addition, an olfaction test and nasal mucosal sensitivity to histamine was serially determined, immediately before and after the course and 6 months after the completion of the course. RESULTS Olfactory abnormalities were observed in 13/41 (32%) subjects and increased nasal mucosal hypersensitivity to histamine was observed in 17/41 (41%) during and immediately after completion of the course. These subjects had evidence of preexisting allergic rhinitis. 6/41 (15%) other students with no prior evidence of allergic rhinitis also exhibited formaldehyde associated clinical symptoms during the dissecting course. However, the symptoms disappeared upon completion of the course in all subjects studied. CONCLUSIONS Temporary abnormalities in the olfaction test and increased nasal mucosal hypersensitivity to histamine were observed in a few students with preexisting allergic rhinitis after environmental exposure of high concentrations of formaldehyde. These effects appeared to be transient.

Carotid artery resection: preoperative temporary occlusion is not always an accurate predictor of collateral blood flow.

Conclusion The morbidity predicted by means of preoperative PET studies does not always correlate with the morbidity experienced after permanent carotid artery occlusion. A pre-resection extracranial–intracranial bypass may be necessary to reduce the risk of neurologic morbidity, in particular when carotid artery resection is planned for tumors involving the skull base. Objectives Carotid artery resection is generally considered the only curative treatment for patients with advanced head and neck carcinoma involving the carotid artery. PET can be used during temporary occlusion of the internal carotid artery to assess the safety of the procedure. The aims of this paper were to clarify the risk of carotid artery resection and the benefit of extracranial–intracranial bypass. Material and methods Twelve patients diagnosed with head and neck cancer adherent to the carotid artery and in proximity to the skull base who had shown good hemispheric collateral blood flow by means of PET underwent carotid artery resection without preoperative bypass. Results Of the 12 patients who underwent carotid artery resection without reconstruction, 10 suffered no serious neurologic complications; however, 2 suffered cerebral infarctions intraoperatively.

Effects of daily intake of Lactobacillus paracasei strain KW3110 on Japanese cedar pollinosis.

Japanese cedar pollinosis is an important contributor to allergic rhinitis in Japan. Lactobacillus may be useful as an immunomodulator and is used widely as a foodstuff. The purpose of the study was to examine the effects of daily intake of the Lactobacillus paracasei strain KW3110 in patients with cedar pollinosis. The effects of daily intake of KW3110 in patients with cedar pollinosis were investigated in 126 patients who received KW3110 or a placebo in a double-blind study. The study began 1 month before the start of the pollen season and lasted for 3 months. A significant reduction of nasal symptoms and the serum level of eosinophil cationic protein and improvement of quality of life scores occurred in the patients who received KW3110 when pollen scattering was low. However, the effects were limited during the peak period of pollen scattering. Intake of KW3110 may reduce allergic inflammation, but the effect is limited.

Identification of Warthin tumor : magnetic resonance imaging versus salivary scintigraphy with technetium-99m pertechnetate

Objective: The aim of this study was to evaluate the accuracy of technetium-99m (Tc-99m) pertechnetate scintigraphy and magnetic resonance (MR) imaging in the diagnosis of Warthin tumor. Methods: Sixteen cases of Warthin tumor and 17 cases of non-Warthin tumor were examined by Tc-99m pertechnetate scintigraphy with lemon juice stimulation and MR imaging, including T1-weighted, T2-weighted, short inversion time inversion recovery, diffusion-weighted, and contrast-enhanced dynamic images. We used the receiver operating characteristic (ROC) curve to evaluate diagnostic accuracy. Results: The mean area under the ROC curves of MR imaging in the diagnosis of Warthin tumor (0.97) was higher than that of Tc-99m pertechnetate scintigraphy (0.88). Conclusion: Magnetic resonance imaging is more useful in the evaluation of Warthin tumor than Tc-99m pertechnetate scintigraphy.

Cedar and Cypress Pollinosis and Allergic Rhinitis: Quality of Life Effects of Early Intervention with Leukotriene Receptor Antagonists

Background: Allergic rhinitis involves inflammation of the nasal passages. The use of nasal steroids is generally very effective in providing significant symptom relief. However, compliance for their use is sometimes poor. Methods: To examine the efficacy of early intervention (before pollen dispersal) with oral cysteinyl leukotriene receptor antagonists (LTRA) on pollinosis in patients with allergy to cedar and Japanese cypress pollens, groups of subjects were treated with LTRA or a placebo for 4 weeks at the beginning of the cedar pollen dispersal season. Subsequently, all patients received nasal steroid therapy concomitantly with LTRA throughout the remaining period of the pollen dispersal season. The effects of such early treatment with LTRA on pollinosis were investigated using symptom scores from an allergy diary and quality of life (QOL) scores. Results: Sneezing and nasal congestion scores were significantly lower in the LTRA-pretreated subjects than observed in the placebo-pretreated patients between weeks 4 and 6 and weeks 3 and 5, respectively. QOL scores improved significantly in all domains after concomitant therapy with nasal steroids. The percent improvement in the nasal congestion score after the concomitant therapy was significantly higher in the LTRA group (69%) than in the placebo group (41%). Conclusion: Significant differences observed in symptoms and in QOL effects between LTRA- and placebo-pretreated patients and the absence of major adverse effects noted in these studies suggest that early intervention with LTRA is beneficial and safe and should be considered in the management of pollinosis-associated allergic rhinitis.

Effects of Aging on the Natural History of Seasonal Allergic Rhinitis in Middle-Aged Subjects in South Chiba, Japan

Background: The natural history of allergic rhinitis has been examined in a few longitudinal studies. The purpose of the study was to investigate the course, development and remission of seasonal allergic rhinitis (SAR) over 10 successive years in middle-aged subjects. Methods: An annual questionnaire survey on allergic rhinitis symptoms combined with an examination of specific IgE has been undertaken in a rural town in south Chiba since 1995. The analyzed subjects were 703 residents who underwent every examination in 1995, 2004 and 2005. In the last 15 years, the annual pollen count in Chiba was highest in 2005. Results: The sensitization rates to cedar pollen decreased with age in the same subject groups over 10 years, but the prevalence of SAR was higher in 2005 compared with 1995. Of the 52 subjects with SAR in 1995, the symptoms had disappeared in 10 subjects in 2005. Specific IgE had converted to negative or borderline in 4 of these patients, had decreased but was still positive in 4 and was increased or unchanged in 2. During the 10-year period, 22 subjects developed SAR, of whom 12 had increased specific IgE and 10 had similar or decreased specific IgE in 2005. Conclusion: SAR induced by cedar pollen takes a chronic course in the majority of middle-aged patients in south Chiba, Japan. The prevalence of SAR increased over 10 years due to a high level of pollen exposure. Changes in specific IgE were not directly associated with the development or remission of SAR.

Seasonal changes in antigen-specific T-helper clone sizes in patients with Japanese cedar pollinosis : a 2-year study

Background Allergic rhinitis (AR) is a typical type I allergic disease that occurs through the induction of allergen‐specific effector T cells. Once established, new effector T cells derive mostly from memory T cells that are capable of surviving for extended periods, although the mechanisms by which these memory functions are maintained have not yet been clarified. In particular, the exact life‐span of memory T cells is still not well understood.

Suppressive effect of locally produced interleukin‐10 on respiratory syncytial virus infection

Interleukin (IL)‐10 is known to be a multifunctional cytokine. This study was designed to evaluate the role of IL‐10 during respiratory syncytial virus (RSV) infection using a C57BL/6 transgenic (TG) mouse model in which the expression of murine IL‐10 cDNA was regulated by a human salivary amylase promoter (IL‐10 TG mice). These mice expressed a large amount of IL‐10 in the nasal mucosa and in salivary glands. Viral replication in the respiratory tract after intranasal infection with RSV was suppressed significantly in IL‐10 TG mice compared to non‐transgenic controls. This suppression was IL‐10 specific, because it was prevented by treating mice with neutralizing anti‐IL‐10 antibodies. We also found that IL‐10‐stimulated T cells displayed cytotoxic activity against infected murine nasal epithelial cells. Previous data indicated that IL‐10 induces Fas ligand (L) expression on mouse T cells. Taken together, these data suggest that Fas/Fas L mediated cytotoxicity is involved in the suppression of RSV replication observed in IL‐10 TG mice after intranasal infection.