The prevalence and clinical features of spasmodic dysphonia: A review of epidemiological surveys conducted in Japan

OBJECTIVES

Spasmodic dysphonia (SD) is a rare disease and its epidemiological status is unclear. This review aimed to explore the current prevalence and clinical features of SD in Japan.

METHODS

We reviewed Japanese surveys of SD and compared them to surveys reported from other countries. We focused on SD prevalence, clinical features (SD type, sex and age), and treatment modalities.

RESULTS

The SD prevalence in Japan was 3.5-7.0/100,000, similar to that in Rochester (NY, USA) and Iceland. Adductor SD predominated (90-95%) and females were four-fold more likely to be affected than males. Mean age at onset was approximately 30 years in Japan. Several years elapsed from onset to diagnosis. The most frequent treatment was botulinum toxin injection, and surgical intervention, particularly type 2 thyroplasty is becoming more popular.

CONCLUSIONS

Our review demonstrated some differences of clinical features of SD in Japan compared with other countries, such as a greater female predominance and younger age of onset. Many physicians and patients may be unfamiliar with the clinical features of SD leading to delayed of diagnosis. Therefore, we proposed diagnostic criteria to facilitate early diagnosis and an appropriate choice of treatment modalities.

Differential isoform expression of SERCA and myosin heavy chain in hypopharyngeal muscles

Composition of slow, fast and hybrid fibres of pharyngeal muscles, associated with pharyngeal movements and regulation, has been rarely studied. The present study aimed to identify expression of sarcoplasmic reticulum Ca2⁺ ATPase (SERCA) and myosin heavy chain (MHC) and hybrid isoforms in different pharyngeal muscles of young and aged rats as well as humans. Isoform expression profiles of SERCA, MHC and hybrid isoforms among six components of pharyngeal muscle were immunohistochemically evaluated in rat and human. The result showed that pharyngeal muscles predominantly expressed fast fibres (SERCA1 and MHCII), whereas expression of slow fibres (SERCA2 and MHCI) was low, but different depending on muscle components. Inner layer of pharyngeal muscles expressed more SERCA2 and hybrid fibres than the outer layer. Pharyngeal muscles in aged rats showed increased hybrid fibers and SERCA2. Human thyropharyngeus also showed a higher portion of fast fibres compared to cricopharyngeus. Thus, in contrast to abundance of fast fibres, slow and hybrid fibres are differentially expressed depending on muscle components and layers as well as aging. These results lead to further understanding of coordinated regulation for speech and swallowing. The unique data presented in this study on SERCA isoform expressions in both rats and human suggest an ability to handle calcium changes according functional demands.

Development of an Oropharyngeal Scope with an Integrated Tongue Depressor: NTOP2013 Study

The oropharynx is examined with a light source such as an electric light, a penlight, or a forehead mirror based on an acquired visual field using a tongue depressor. However, it is extremely difficult to obtain objective and reproducible images of tissue within the pharynx required in recent years with these methods, and insufficient progress in the examination tools has been made. There is an increasing need to develop a method for display during oropharyngeal examination. We conducted the present study to develop a novel oropharyngeal endoscope as an objective observation method.

Hearing vulnerability after noise exposure in a mouse model of reactive oxygen species overproduction

Previous studies have convincingly argued that reactive oxygen species (ROS) contribute to the development of several major types of sensorineural hearing loss, such as noise-induced hearing loss (NIHL), drug-induced hearing loss, and age-related hearing loss. However, the underlying molecular mechanisms induced by ROS in these pathologies remain unclear. To resolve this issue, we established an in vivo model of ROS overproduction by generating a transgenic (TG) mouse line expressing the human NADPH oxidase 4 (NOX4, NOX4-TG mice), which is a constitutively active ROS-producing enzyme that does not require stimulation or an activator. Overproduction of ROS was detected at the cochlea of the inner ear in NOX4-TG mice, but they showed normal hearing function under baseline conditions. However, they demonstrated hearing function vulnerability, especially at high-frequency sounds, upon exposure to intense noise, which was accompanied by loss of cochlear outer hair cells (OHCs). The vulnerability to loss of hearing function and OHCs was rescued by treatment with the antioxidant Tempol. Additionally, we found increased protein levels of the heat-shock protein 47 (HSP47) in models using HEK293 cells, including H₂ O₂ treatment and cells with stable and transient expression of NOX4. Furthermore, the up-regulated levels of Hsp47 were observed in both the cochlea and heart of NOX4-TG mice. Thus, antioxidant therapy is a promising approach for the treatment of NIHL. Hsp47 may be an endogenous antioxidant factor, compensating for the chronic ROS overexposure in vivo, and counteracting ROS-related hearing loss.

An oral pharyngeal scope for objective oropharyngeal examination: a new device for oropharyngeal study

OBJECTIVE

There has been little progress in examination of the oropharynx with a light source such as electric light, a penlight, or a forehead mirror over the past 100 years. It is therefore necessary to develop methods to display and record oropharyngeal observations.

METHOD

Since the aim of this study was to assess the safeness to use from the perspective of physicians, medical staffs, patients, and patients' families and usefulness of pharyngeal scope, the number of devices was limited, the number of patients was not set based on hypothetical statistical tests.

RESULTS

A total of 150 volunteers were enrolled in this study. Among them, 96 underwent examination alone and the remaining 28 underwent treatment procedures. The study was done without any complications in all 150 cases. Most (91.3%) physicians hoped to continue using the new device if available. When comparing the use of the device for observation alone and for treatment procedures, there was no significant difference for evaluation items (p > .05) except convenience factor which received a significantly different (p = .0154) evaluation from physicians for observation alone and for treatment procedures. A positive evaluation was received about examination, recording/display and explanation from the patients and patients' families.

CONCLUSIONS

Our new device received positive evaluations by who underwent examination of the oral cavity and pharynx, recording of the results, and treatment procedures.

Novel role of Rac-Mid1 signaling in medial cerebellar development

Rac signaling impacts a relatively large number of downstream targets; however, few studies have established an association between Rac pathways and pathological conditions. In the present study, we generated mice with double knockout of Rac1 and Rac3 (Atoh1-Cre;Rac1^flox/flox;Rac3^-/- ) in cerebellar granule neurons (CGNs). We observed impaired tangential migration at E16.5, as well as numerous apoptotic CGNs at the deepest layer of the external granule layer (EGL) in the medial cerebellum of Atoh1-Cre;Rac1^flox/flox;Rac3^-/- mice at P8. Atoh1-Cre;Rac1^flox/flox;Rac3^-/- CGNs differentiated normally until expression of p27^kip1 and NeuN in the deep EGL at P5. Primary CGNs and cerebellar microexplants from Atoh1-Cre;Rac1^flox/flox;Rac3^-/- mice exhibited impaired neuritogenesis, which was more apparent in Map2-positive dendrites. Such findings suggest that impaired tangential migration and final differentiation of CGNs have resulted in decreased cerebellum size and agenesis of the medial internal granule layer, respectively. Furthermore, Rac depleted/deleted cells exhibited decreased levels of Mid1 and impaired mTORC1 signaling. Mid1 depletion in CGNs produced mild impairments in neuritogenesis and reductions in mTORC1 signaling. Thus, a novel Rac-signaling pathway (Rac1-Mid1-mTORC1) may be involved in medial cerebellar development.

REVIEW ■ : The Suprachiasmatic Nucleus: A Circadian Oscillator

The suprachiasmatic nucleus (SCN) is considered to be a circadian oscillator that regulates a set of phys iological aspects of behavior, including sleep-wakefulness and hormone release in mammalian species. In this review, we describe recent research that has begun to reveal the functional organization of the SCN. The SCN, which consists of a bilateral pair of tiny nuclei located just above the optic chiasm, contains several kinds of peptidergic neurons, but vasoactive intestinal peptide (VIP), arginine vasopressin (AVP), and somatostatin (SOM) neurons are the main components. VIP neurons and AVP neurons show distinctly different locations in the SCN; the former are found in the ventrolateral portion, whereas the latter are localized in the dorsomedial portion. VIP neurons receive all neuronal inputs from other regions of the CNS, such as those evoked by photic stimulation via the retinal ganglion cells and those relayed by 5HT inner vation from the raphe nuclei. VIP neurons relay their information to other kinds of neurons in the SCN, such as AVP and SOM neurons. VIP neurons, thus, may play a significant role in entrainment of circadian rhythm. VIP, AVP, SOM, and their mRNAs show rhythmic fluctuations that are predicted by this model; VIP and its mRNA show diurnal variation under the influence of photic stimulation, whereas AVP, SOM, and their mRNAs show endogenous rhythms. Immediate early genes (lEGs), such as c-fos mRNA, are also expressed in VIP neurons in the SCN, and IEG expression in the cells appears to be modified by photic stimuli. Together with transplantation studies showing that exogenous SCN tissue tends to restore circadian rhythm in arrhythmic animals, these results are beginning to clarify the function of the SCN in setting, maintaining, and resetting the biological clock. NEUROSCIENTIST 3:215-225, 1997

Age-Related Expression of α-Gustducin in the Rat Larynx

Objectives:

The age-related changes in distribution of α-gustducin–immunoreactive structures in the larynx of Sprague-Dawley rats were studied.

Methods:

For this purpose, tissues obtained from 12 male rats ranging in age from 5 to 21 weeks were compared with respect to the distribution and morphology of laryngeal taste buds immunoreactive for α-gustducin, the α-subunit of a taste cell–specific G protein.

Results:

Three different morphological types of α-gustducin–immunoreactive structures were seen: typical gemmal forms, clusters composed of 2 or 3 cells, and isolated immunoreactive cells not associated with taste buds. α-Gustducin–immunoreactive structures were most abundant in the epiglottis in all age groups. α-Gustducin–immunoreactive cells in rats seem to be located along the lateral food channels, in which they may come in contact with food. The total number of these α-gustducin–immunoreactive structures did not show any age-related changes, but the percentage of solitary immunoreactive cells in 5-week-old rats was significantly larger than the percentages in 8-, 14-, and 21-week-old animals.

Conclusions:

Solitary α-gustducin–immunoreactive cells, which are abundant in 5-week-old rats but are found in fewer numbers along the base of the epiglottis in mature rats, may be nociceptic in function, whereas the chemosensory clusters or buds that contain α-gustducin–positive cells and are distributed along the lateral food channels on the pharyngeal side of the larynx may have a role in gustatory reception.

A case of recurrent malignant triton tumor successfully treated with radiotherapy

A 15-year-old female was previously admitted to another hospital because of painless swelling of the lateral right nasal ala for 2 months. Magnetic resonance imaging revealed an expansive enhancing lesion in close proximity to the anterior surface of the right maxillary sinus and lateral wall of the right nasal cavity. Tumor extirpation was performed via the supragingival transantral approach under general anesthesia. Histopathological study revealed a malignant triton tumor (MTT) arising from the nasal vestibule. The patient was referred to our department for consultation regarding additional treatment. Because the surgical margin was positive and MTT has high malignant potential, we recommended expansion re-surgical treatment following immediate free-flap reconstruction and postoperative radiotherapy, but family consent was not obtained. Tumor regrowth was noted 1 month after her first visit to our department. The patient and her family accepted radiotherapy instead of surgical treatment. Complete remission was achieved by radiotherapy alone. No local recurrence or distant metastasis was observed for 30 months after radiotherapy. The conventional mode of treatment for MTT is radical excision followed by high-dose radiotherapy. However, this case is remarkable because our patient experienced complete remission by simple radiotherapy.

Expression of Sex Steroid Hormone Receptors in Vagal Motor Neurons Innervating the Trachea and Esophagus in Mouse

The medullary vagal motor nuclei, the nucleus ambiguus (NA) and dorsal motor nucleus of the vagus (DMV), innervate the respiratory and gastrointestinal tracts. We conducted immunohistochemical analysis of expression of the androgen receptor (AR) and estrogen receptor α (ERα), in relation to innervation of the trachea and esophagus via vagal motor nuclei in mice. AR and ERα were expressed in the rostral NA and in part of the DMV. Tracing experiments using cholera toxin B subunit demonstrated that neurons of vagal motor nuclei that innervate the trachea and esophagus express AR and ERα. There was no difference in expression of sex steroid hormone receptors between trachea- and esophagus-innervating neurons. These results suggest that sex steroid hormones may act on vagal motor nuclei via their receptors, thereby regulating functions of the trachea and esophagus.

Role of the retrotrapezoid nucleus/parafacial respiratory group in coughing and swallowing in guinea pigs

The retrotrapezoid/parafacial respiratory group (RTN/pFRG) located ventral to the facial nucleus plays a key role in regulating breathing, especially enhanced expiratory activity during hypercapnic conditions. To clarify the roles of the RTN/pFRG region in evoking coughing, during which reflexive enhanced expiration is produced, and in swallowing, during which the expiratory activity is consistently halted, we recorded extracellular activity from RTN/pFRG neurons during these fictive behaviors in decerebrate, paralyzed, and artificially ventilated guinea pigs. The activity of the majority of recorded respiratory neurons was changed in synchrony with coughing and swallowing. To further evaluate the contribution of RTN/pFRG neurons to these nonrespiratory behaviors, the motor output patterns during breathing, coughing, and swallowing were compared before and after brain stem transection at the caudal margin of RTN/pFRG region. In addition, the effects of transection at its rostral margin were also investigated to evaluate pontine contribution to these behaviors. During respiration, transection at the rostral margin attenuated the postinspiratory activity of the recurrent laryngeal nerve. Meanwhile, the late expiratory activity of the abdominal nerve was abolished after caudal transection. The caudal transection also decreased the amplitude of the coughing-related abdominal nerve discharge but did not abolish the activity. Swallowing could be elicited even after the caudal end transection. These findings raise the prospect that the RTN/pFRG contributes to expiratory regulation during normal respiration, although this region is not an essential element of the neuronal networks involved in coughing and swallowing.

Differential responses to steroid hormones in fibroblasts from the vocal fold, trachea, and esophagus

There is accumulating evidence that fibroblasts are target cells for steroids such as sex hormones and corticoids. The characteristics of fibroblasts vary among tissues and organs. Our aim in this study is to examine differences in responses to steroid hormones among fibroblasts from different cervicothoracic regions. We compared the actions of steroid hormones on cultured fibroblasts from the vocal folds, which are considered to be the primary target of steroid hormones, and the trachea and esophagus in adult male rats. Expression of steroid hormone receptors (androgen receptor, estrogen receptor α, and glucocorticoid receptor) was identified by immunofluorescence histochemistry. Androgen receptor was much more frequently expressed in fibroblasts from the vocal fold than in those from the trachea and esophagus. Cell proliferation analysis showed that administration of testosterone, estradiol, or corticosterone suppressed growth of all 3 types of fibroblasts. However, mRNA expression for extracellular matrix-associated genes, including procollagen I and III and elastin, and hyaluronic acid synthase I was elevated only by addition of testosterone to fibroblasts from the vocal fold. These results indicate that each steroid hormone exerts region-specific effects on cervicothoracic fibroblasts with different properties through binding to specific receptors.

Aberrant Myosin 1b Expression Promotes Cell Migration and Lymph Node Metastasis of HNSCC

Lymph node metastasis is the major clinicopathologic feature associated with poor prognosis in patients with head and neck squamous cell carcinoma (HNSCC). Here, web-based bioinformatics meta-analysis was performed to elucidate the molecular mechanism of lymph node metastasis of human HNSCC. Preferential upregulation of Myosin 1b (MYO1B) transcript in HNSCC datasets was identified. Myo1b mRNA was highly expressed in human HNSCC cells and patient tissue specimens compared with their normal counterparts as shown by quantitative PCR (qPCR) analyses. Immunohistochemistry (IHC)-detected Myo1b expression was significantly correlated with lymph node metastases in patients with oral cancer of the tongue. HNSCC with high expression of Myo1b and chemokine receptor 4 (CCR4), another metastasis-associated molecule, was strongly associated with lymph node metastasis. RNA interference (RNAi) of Myo1b in HNSCC cells, SAS and HSC4, significantly inhibited migratory and invasive abilities through decreased large protrusion formation of cell membranes. Finally, Myo1b knockdown in SAS cells significantly inhibited in vivo cervical lymph node metastases in a cervical lymph node metastatic mouse model system.

IMPLICATIONS

Myo1b is functionally involved in lymph node metastasis of human HNSCC through enhanced cancer cell motility and is an attractive target for new diagnostic and therapeutic strategies for patients with HNSCC.

Ocular surface reconstruction with a tissue-engineered nasal mucosal epithelial cell sheet for the treatment of severe ocular surface diseases

Severe ocular surface diseases (OSDs) with severe dry eye can be devastating and are currently some of the most challenging eye disorders to treat. To investigate the feasibility of using an autologous tissue-engineered cultivated nasal mucosal epithelial cell sheet (CNMES) for ocular surface reconstruction, we developed a novel technique for the culture of nasal mucosal epithelial cells expanded ex vivo from biopsy-derived human nasal mucosal tissues. After the protocol, the CNMESs had 4-5 layers of stratified, well-differentiated cells, and we successfully generated cultured epithelial sheets, including numerous goblet cells. Immunohistochemistry confirmed the presence of keratins 3, 4, and 13; mucins 1, 16, and 5AC; cell junction and basement membrane assembly proteins; and stem/progenitor cell marker p75 in the CNMESs. We then transplanted the CNMESs onto the ocular surfaces of rabbits and confirmed the survival of this tissue, including the goblet cells, up to 2 weeks. The present report describes an attempt to overcome the problems of treating severe OSDs with the most severe dry eye by treating them using tissue-engineered CNMESs to supply functional goblet cells and to stabilize and reconstruct the ocular surface. The present study is a first step toward assessing the use of tissue-engineered goblet-cell transplantation of nonocular surface origin for ocular surface reconstruction.

Maintenance of stereocilia and apical junctional complexes by Cdc42 in cochlear hair cells

Cdc42 is a key regulator of dynamic actin organization. However, little is known about how Cdc42-dependent actin regulation influences steady-state actin structures in differentiated epithelia. We employed inner ear hair-cell-specific conditional knockout to analyze the role of Cdc42 in hair cells possessing highly elaborate stable actin protrusions (stereocilia). Hair cells of Atoh1-Cre;Cdc42(flox/flox) mice developed normally but progressively degenerated after maturation, resulting in progressive hearing loss particularly at high frequencies. Cochlear hair cell degeneration was more robust in inner hair cells than in outer hair cells, and began as stereocilia fusion and depletion, accompanied by a thinning and waving circumferential actin belt at apical junctional complexes (AJCs). Adenovirus-encoded GFP-Cdc42 expression in hair cells and fluorescence resonance energy transfer (FRET) imaging of hair cells from transgenic mice expressing a Cdc42-FRET biosensor indicated Cdc42 presence and activation at stereociliary membranes and AJCs in cochlear hair cells. Cdc42-knockdown in MDCK cells produced phenotypes similar to those of Cdc42-deleted hair cells, including abnormal microvilli and disrupted AJCs, and downregulated actin turnover represented by enhanced levels of phosphorylated cofilin. Thus, Cdc42 influenced the maintenance of stable actin structures through elaborate tuning of actin turnover, and maintained function and viability of cochlear hair cells.

Japanese Board Certification System for head and neck surgeons

The Japan Society for Head and Neck Surgery (JSHNS) started a board certification system for head and neck surgeons in 2010. To become certified, the following qualification and experiences are required: (1) board certification as otorhinolaryngologist, (2) 2 years of clinical experience in a board-certified training facility, (3) clinical care of 100 patients with head and neck cancer under the supervision of board-certified faculty and (4) surgical experience in 50 major head and neck surgical procedures, including 20 neck dissections, under the supervision of board-certified faculty. The following scientific activities are also required during the preceding 5 years: (1) two clinical papers on head and neck cancers presented at major scientific meetings, (2) one clinical paper on head and neck cancer published in a major journal, (3) attendance at two annual meetings of JSHNS and (4) enrolment in three educational programs approved by JSHNS. The qualifying examination consists of multiple choice tests and oral examinations. A total of 151 head and neck surgeons were certified in 2010 followed by 43 in 2011 and 34 in 2012, while the membership of JSHNS dramatically increased from 1201 in 2007 to 1748 in 2013. Although the board certification system for head and neck surgeons was started only recently, it has encouraged many residents and fellows as well as established head and neck surgeons. We believe that this system will contribute to further advancement in the clinical practice for head and neck cancers in Japan.

Activity of respiratory neurons in the rostral medulla during vocalization, swallowing, and coughing in guinea pigs

To examine the relationship between the neuronal networks underlying respiration and non-respiratory behaviors such as vocalization and airway defensive reflexes, we compared the activity of respiratory neurons in the ventrolateral medulla during breathing with that during non-respiratory behaviors including vocalization, swallowing, and coughing in guinea pigs. During fictive vocalization the activity of augmenting expiratory neurons ceased, whereas the other types of expiratory neurons did not show a consistent tendency of increasing or decreasing activity. All inspiratory neurons discharged in synchrony with the phrenic nerve activity. Most of the phase-spanning neurons were activated throughout the vocal phase. During fictive swallowing, many expiratory and inspiratory neurons were silent, whereas many phase-spanning neurons were activated. During fictive coughing, many expiratory neurons were activated during the expiratory phase of coughing. Most inspiratory neurons discharged in parallel with the phrenic nerve activity during coughing. Many phase-spanning neurons were activated during the expiratory phase of coughing. These findings indicate that the medullary respiratory neurons help shape respiratory muscle nerve activity not only during breathing but also during these non-respiratory behaviors, and thus suggest that at least some of the respiratory neurons are shared among the neuronal circuits underlying the generation of breathing and non-respiratory behaviors.

Middle ear malformations in identical twins

The majority of the congenital anomalies of middle ear are solitary and a non-hereditary. We report cases of identical twins with congenital incudo-stapedial disconnection. Case 1 was an 8-year-old girl. Hearing impairment was identified at the age of three. She was referred to our university hospital in April 2005. Pure-tone audiogram showed conductive hearing impairments. Computed tomography (CT) revealed the incudo-stapedial disconnections in both ears. The exploratory tympanotomies on the right and left ears were performed in May and July 2005, respectively. The surgical findings showed absence of the long process and presence of the lenticular process of the incus in both ears. After the reconstructions of ossicular chain, the hearing of both ears improved. Case 2 was an 11-year-old girl. The hearing impairment of the right ear was identified in May 2008. She was referred to our university hospital three months later. Pure-tone audiogram showed the conductive hearing impairment in the right ear. CT revealed the incudo-stapedial disconnection in the right ear. The surgery showed the same findings as those of case 1. Anomalies of both cases suggest that the lenticular process of the incus and the stapes originate from a common primordium.

The mechanism underlying maintenance of the endocochlear potential by the K+ transport system in fibrocytes of the inner ear

  The endocochlear potential (EP) of +80 mV in the scala media, which is indispensable for audition, is controlled by K+ transport across the lateral cochlear wall. This wall includes two epithelial barriers, the syncytium and the marginal cells. The former contains multiple cell types, such as fibrocytes, which are exposed to perilymph on their basolateral surfaces. The apical surfaces of the marginal cells face endolymph. Between the two barriers lies the intrastrial space (IS), an extracellular space with a low K+ concentration ([K+]) and a potential similar to the EP. This intrastrial potential (ISP) dominates the EP and represents the sum of the diffusion potential elicited by a large K+ gradient across the apical surface of the syncytium and the syncytium's potential, which is slightly positive relative to perilymph. Although a K+ transport system in fibrocytes seems to contribute to the EP, the mechanism remains uncertain. We examined the electrochemical properties of the lateral wall of guinea pigs with electrodes sensitive to potential and K+ while perfusing into the perilymph of the scala tympani blockers of Na+,K+-ATPase, the K+ pump thought to be essential to the system. Inhibiting Na+,K+-ATPase barely affected [K+] in the IS but greatly decreased [K+] within the syncytium, reducing the K+ gradient across its apical surface. The treatment hyperpolarized the syncytium only moderately. Consequently, both the ISP and the EP declined. Fibrocytes evidently use the Na+,K+-ATPase to achieve local K+ transport, maintaining the syncytium's high [K+] that is crucial for the K+ diffusion underlying the positive ISP.

Autocrine and paracrine loops between cancer cells and macrophages promote lymph node metastasis via CCR4/CCL22 in head and neck squamous cell carcinoma

Lymph node metastasis is a poor prognostic factor for patients with head and neck squamous cell carcinoma (HNSCC). However, its molecular mechanism has not yet been fully understood. In our study, we investigated the expression of CCR4 and its ligand CCL22 in the HNSCC tumor microenvironment and found that the CCR4/CCL22 axis was involved in lymph node metastasis of HNSCC. CCR4 was expressed in 20 of 31 (64.5%) human tongue cancer tissues, and its expression was significantly correlated with lymph node metastasis (p < 0.01) and lymphatic invasion (p < 0.05). CCR4 was expressed in three of five human HNSCC cell lines tested. CCR4(+) HNSCC cells, but not CCR4(-) cells, showed enhanced migration toward CCL22, indicating that functional CCR4 was expressed in HNSCC cell lines. CCL22 was also expressed in cancer cells (48.4% of tongue cancer tissues) or CD206(+) M2-like macrophages infiltrated in tumors and draining lymph nodes. CCL22 produced by cancer cells or CD206(high) M2-like macrophages increased the cell motility of CCR4(+) HNSCC cells in vitro in an autocrine or paracrine manner. In the mouse SCCVII in vivo model, CCR4(+) cancer cells, but not CCR4(-) cells, metastasized to lymph nodes which contained CCL22 producing M2-like macrophages. These results demonstrate that lymph node metastasis of CCR4(+) HNSCC is promoted by CCL22 in an autocrine or M2-like macrophage-dependent paracrine manner. Therefore, the CCR4/CCL22 axis may be an attractive target for the development of diagnostic and therapeutic strategies for patients with HNSCC.

K(+)-Cl(-) cotransporter 1 (KCC1) negatively regulates NGF-induced neurite outgrowth in PC12 cells

Potassium chloride cotransporters (KCCs) mediate electroneutrally-coupled transport of K(+) and Cl(-), and play crucial roles in various cell functions including regulation of cell volume and homeostasis of cellular Cl(-)content. Four isoforms of KCCs (KCC1, 2, 3, and 4) have been identified. KCC1 is ubiquitously expressed, whereas KCC2 is mainly expressed in neuronal cells of central nervous system. KCC3 is highly expressed in heart, skeletal muscle, kidney, lung and placenta. KCC4 is mainly expressed in epithelial cells. In this study, we investigated roles of KCCs in NGF-induced neurite outgrowth of rat pheochromocytoma PC12 cells. The most abundantly expressed isoform in PC12 cells was KCC1. Inhibition of KCCs using [(dihydronindenyl)oxy] alkanoic acid (DIOA), an inhibitor of KCCs, enhanced the NGF-induced neurite outgrowth of PC12 cells in a dose-dependent manner. Treatment of PC12 cells with NGF significantly decreased mRNA expression of KCC1, whereas other isoforms, KCC2-4, showed no changes in their mRNA expression in response to NGF treatment. Knockdown of KCC1 using small interfering RNA (siRNA) enhanced the NGF-induced neurite outgrowth. These results suggest that KCC1 negatively regulates the NGF-induced neurite outgrowth of PC12 cells.

Laryngeal stenosis in a patient with severe congenital neutropenia

OBJECTIVES/HYPOTHESIS

We report the first case of laryngeal stenosis with granuloma in a patient with severe congenital neutropenia (SCN).

STUDY DESIGN

Case report and retrospective review.

METHODS

Review of medical records.

RESULTS

A 6-year-old female who was diagnosed with SCN presented with a cough and wheezing. An endoscopic study revealed laryngeal stenosis with granuloma. Tracheotomy and direct laryngoscopy were performed under general anesthesia, and administration of granulocyte colony-stimulating factor was started. The laryngeal granuloma disappeared 3 weeks later, and the tracheal stoma was closed.

CONCLUSIONS

Presence of a laryngeal lesion should be considered in SCN patients with persistent airway symptoms.

Localization and regulation of aquaporins in the murine larynx

CONCLUSION

Expression of aquaporins (AQPs) in the vocal folds and the parasympathetic regulation of AQPs in the laryngeal glands may be important for controlling laryngeal secretion and vocal fold hydration. These findings are thought to be an initial step towards understanding potential mechanisms of water flow through the vocal fold surface.

OBJECTIVES

Lubrication of the vocal folds is important for phonation and laryngeal defense. However, the system of water transport in the laryngeal epithelium has not yet been clarified. We investigated the expression of AQP water channnels (AQP1-9) in the murine larynx and examined the neural regulating mechanisms of these subtypes.

METHODS

The distribution of AQPs (AQP1-9) in the murine larynx was examined by immunohistochemistry. Next, the neural mechanism regulating AQPs in the larynx was investigated using unilaterally vagotomized mice.

RESULTS

AQP1, 4, and 5 were expressed in the laryngeal epithelium including the vocal folds. Vocal fold AQP expression was minimal at the vocal process. AQP2, 3, 5, 6, 7, and 8 were localized to the submucosal glands. Expression of AQPs in the vagotomized region was significantly decreased compared with the contralateral intact side. The expression in the laryngeal glands was also decreased in the aged mice.

RB1CC1 activates the p16 promoter through the interaction with hSNF5

RB1-inducible coiled-coil 1 (RB1CC1, also known as FIP200) is involved in dephosphorylation and increase of retinoblastoma tumor suppressor protein (RB1), but the RB1CC1 molecular mechanism in the dephosphorylation of RB1 is not fully understood. We determined that RB1CC1 activates the expression of p16 (also called INK4a/CDKN2a) through the activation of its promoter, using chromatin immunoprecipitation (ChIP) and p16 promoter-luciferase reporter assays. In addition, RB1CC1 essentially requires binding with hSNF5 (also known as BAF47/INI1, a chromatin-remodeling factor) to activate the p16 promoter, in order to enhance the RB1 pathway and acts as a tumor suppressor. Evaluation of the RB1CC1 mechanism of action is expected to provide useful information for clinical practice and future therapeutic strategies in human cancers.

RECQL1 and WRN proteins are potential therapeutic targets in head and neck squamous cell carcinoma

RECQL1 and WRN proteins are RecQ DNA helicases that participate in suppression of DNA hyper-recombination and repair. In this study, we report evidence supporting their candidacy as cancer therapeutic targets. In hypopharyngeal carcinomas, which have the worst prognosis among head and neck squamous cell carcinomas (HNSCC) that are rapidly rising in incidence, we found that RECQL1 and WRN proteins are highly expressed and that siRNA-mediated silencing of either gene suppressed carcinoma cell growth in vitro. Similarly, siRNA administration in a murine xenograft model of hypopharyngeal carcinoma markedly inhibited tumor growth. Moreover, combining either siRNA with cis-platinum (II) diammine dichloride significantly augmented the in vivo anticancer effects of this drug that is used commonly in HNSCC treatment. Notably, we observed no recurrence of some tumors following siRNA treatment in this model. Our findings offer a preclinical proof of concept for RECQL1 and WRN proteins as novel therapeutic targets to treat aggressive HNSCC and perhaps other cancers.

RB1CC1 together with RB1 and p53 predicts long-term survival in Japanese breast cancer patients

RB1-inducible coiled-coil 1 (RB1CC1) plays a significant role in the enhancement of the retinoblastoma tumor suppressor (RB1) pathway and is involved in breast cancer development. However, RB1CC1's role in clinical progression of breast cancer has not yet been evaluated, so, as a first step, it is necessary to establish its usefulness as a tool to evaluate breast cancer patients. In this report, we have analyzed the correlation between abnormalities in the RB1CC1 pathway and long-term prognosis, because disease-specific death in later periods (>5 years) of the disease is a serious problem in breast cancer. Breast cancer tissues from a large cohort in Japan were evaluated by conventional immunohistochemical methods for the presence of the molecules involved in the RB1CC1 pathway, including RB1CC1, RB1, p53, and other well-known prognostic markers for breast cancer, such as estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2. The correlation between the immunohistochemical results and clinical outcomes of 323 breast cancer patients was analyzed using a Kaplan-Meier log-rank test and a multivariate Cox proportional hazards regression analysis. Absence of nuclear RB1CC1 expression was associated with the worst prognosis (Log-rank test, Chi-Square value = 17.462, p<0.0001). Dysfunction of either one of RB1CC1, RB1, or p53 was associated with the highest risk for cancer-specific death, especially related to survival lasting more than 5 years (multivariate Cox proportional hazard ratio = 3.951, 95% Confidence Interval = 1.566–9.967, p = 0.0036). Our present data demonstrate that the combined evaluation of RB1CC1, RB1 and p53 by conventional immunohistochemical analysis provides an accurate prediction of the long-term prognoses of breast cancer patients, which can be carried out as a routine clinical examination.

[Congenital ossicular malformation: a study of 27 ears]

Despite otological surgical progress improving clinical congenital ossicular malformation management, some cases remain inadequately treated. We report 27 cases of congenital ossicular malformation, focusing on reasons for remaining or delayed postoperative hearing loss evaluated in 27 congenital ossicular malformation cases in Kyoto Prefecture from 2002 to 2008. Overall success was 93% (25/27) 6 months postoperatively. Two ears had no hearing improvement and three delayed hearing loss 8 to 48 months postoperatively. The first two ears underwent small fenestration stapedotomy with malleus attachment piston, and the other three tympanoplasty type III using an autologous ossicle or total ossicular replacement prosthesis (TORP) as a columella. We discuss problems and solutions using a malleus attachment piston or prosthesis, preoperative audio-and radiological findings, and operative findings including facial nerve anomaly and congenital cholesteatoma.

RB1CC1 activates RB1 pathway and inhibits proliferation and cologenic survival in human cancer

RB1-inducible coiled-coil 1 (RB1CC1, also known as FIP200) plays a role in the enhancement of the RB1 pathway through the direct binding to a GC-rich region 201bp upstream (from the initiation ATG) of the RB1 promoter. Here, we identified hSNF5 and p53 as the binding partners of RB1CC1 by immunoprecipitation and immunofluorescence assays. Interaction between these molecules and the RB1 pathway was analyzed by the assays of chromatin immunoprecipitation, luciferase-reporter, reverse transcription-polymerase chain reaction and immunoblot. The tumor growth suppression by RB1CC1 was evaluated by flow cytometry or by a cell growth assay. The nuclear RB1CC1 complex involving hSNF5 and/or p53 activated transcription of RB1, p16 and p21, and suppressed tumor cell growth. Furthermore, nuclear RB1CC1 expression significantly correlated with those of RB1 and p16 in breast cancer tissue in vivo, and the Ki-67 proliferation index was dependent on p53 as well as RB1CC1. The present study indicates that RB1CC1 together with hSNF5 and/or p53 enhances the RB1 pathway through transcriptional activation of RB1, p16 and p21. Evaluation of RB1CC1 expression combined with RB1 and p53 status is expected to provide useful information in clinical practice and future therapeutic strategies in breast cancer.

Synergistic effect between proteasome and autophagosome in the clearance of polyubiquitinated TDP-43

Cytoplasmic aggregates of ubiquitinated TAR DNA-binding protein 43 (TDP-43) are a pathological hallmark of amyotrophic lateral sclerosis (ALS). However, the mechanism of TDP-43 polyubiquitination remains elusive. We investigated the effect of nuclear exclusion of TDP-43 on aggregate formation and fragmentation, using TDP-43 expression constructs for WT or mutant TDP-43 with a modified nuclear localizing signal (LQ-NLS). Overexpression of the LQ-NLS mutant alone induced no detectable cytoplasmic aggregates during a 72-hr period. Polyubiquitination of both WT TDP-43 and the LQ-NLS mutant was similar in total cell lysates exposed to the proteasome inhibitor lactacystin. However, analysis of subcellular fractions demonstrated a higher concentration of polyubiquitinated TDP-43 in the nuclear fraction than in the cytosol for WT, and vice versa for the LQ-NLS mutant. Polyubiquitin-charged WT and mutant TDP-43 were highly concentrated in the membrane/microsome fraction, which was also positive for the autophagosome marker LC3. In addition, the autophagy inhibitor 3-methyladenine (3MA) blocked degradation of both TDP-43 types, whereas lactacystin was minimally restorative. Furthermore, lactacystin plus 3MA induced prominent cytoplasmic aggregates. We also demonstrated mediation of TDP-43 polyubiquitination by lysine 48 of ubiquitin, indicating a degradation signal in both TDP-43 types. This is the first report delineating the distribution of polyubiquitinated TDP-43 and the degradation pathway of TDP-43 and clarifying the crucial role of autophagosomes in TDP-43 clearance. We also demonstrate that nuclear exclusion itself is not an immediate trigger for ALS pathology. Further clarification of the mechanism of polyubiquitination of TDP-43 and the role of autophagosomes may help in understanding and treating ALS.

Double vascular anastomosis in the neck for reliable free jejunal transfer

To reduce the possibility of necrosis in free jejunal transfer after total pharyngolaryngo-oesophagectomy, we made a second set of arterial and venous anastomoses in addition to the usual cervical arterial and venous anastomoses. To obtain two different arterial flows (carotid and subclavian systems), the recipient arteries were the superior thyroid and the transverse cervical. For venous flow, the internal and external jugular veins were used. All flaps survived. This procedure, which is limited to the already dissected neck with no procedures in other areas, is less invasive than others. Its advantages are that when one vessel has thrombosed the other vessel functions as a safety valve, and the greater pliability of the vascular pedicles makes it easier to reach the recipient vessels. Because this method is theoretically safe and results in less possibility of losing a flap when the anastomosis is unreliable, the double-pedicled transfer can be an option for safer free jejunal transfer.

Axonal ligation induces transient redistribution of TDP-43 in brainstem motor neurons

Nuclear exclusion of TAR DNA binding protein 43 (TDP-43) and formation of cytosolic aggregates are a pathological characteristic of amyotrophic lateral sclerosis (ALS). However, the molecular basis of the aberrant distribution of TDP-43 remains elusive. Here, we show evidence that axonal ligation induced transient nuclear exclusion and peripheral accumulation of TDP-43, without apparent cytosolic aggregates in hypoglossal neurons in mice. Immunohistochemistry showed marked loss of nuclear TDP-43 7-14 days after ligation, which was accompanied by reduction of choline acetyltransferase (ChAT). TDP-43 staining was restored in the nucleus on day 28 exclusively in the neurons with normalized ChAT expression. We also showed that importin beta, which was shown to mediate nuclear transport of TDP-43 was downregulated transiently by nerve ligation. The analysis of the peripheral nerves proximal to the ligation revealed that TDP-43 markedly accumulated with a concomitant decrease in active autophagosome. Moreover, we showed that TDP-43 was present in the microsome fraction containing endoplasmic reticulum (ER) or autophagosomes in the brainstem section, indicating that TDP-43 is axonally transported with vesicles. These results indicate that axonal damage is associated with redistribution of TDP-43 through the combination of defective axonal autophagy periphery and the impaired nuclear transport system in the soma. Moreover, it was also shown that transient redistribution of TDP-43 does not prevent motor neurons from axonal regeneration. Therefore, our data suggest that the subcellular distribution of TDP-43 correlates to the innervation status of motor neurons, which may be governed by unidentified cause of ALS.

RB1CC1 activates the promoter and expression of RB1 in human cancer

RB1-inducible coiled-coil 1 (RB1CC1, also known as FIP200) is a tumor suppressor implicated in the regulation of RB1 (retinoblastoma 1) expression. However, the molecular mechanism of RB1 regulation by RB1CC1 has not been elucidated. Here, we demonstrate that nuclear RB1CC1 binds to the RB1 promoter using chromatin immunoprecipitation assays with anti-RB1CC1 antibody. Luciferase assays with RB1 promoter reporter plasmids revealed that RB1CC1 activated the RB1 promoter through the 201 bp upstream GC-rich region (from the initiation ATG). Electrophoretic mobility shift assay and Western blot analysis supported RB1CC1 binding to the GC-rich region of the RB1 promoter. In addition, the C-terminus of RB1CC1 was required for nuclear localization and subsequent RB1 promoter activation. Furthermore, the expression levels of RB1CC1 and RB1 significantly correlated with in vivo breast cancer tissues as determined by immunohistochemical analysis. These data indicate that nuclear RB1CC1 directly activates the RB1 promoter to enhance RB1 expression in cancer cells. Evaluation of RB1CC1 in various types of human cancer tissues is expected to provide useful information for clinical practice and future therapeutic strategies.

Axotomy alters alternative splicing of choline acetyltransferase in the rat dorsal motor nucleus of the vagus nerve

Choline acetyltransferase of the peripheral type (pChAT) is a splice variant that lacks exons 6-9 of the common-type ChAT (cChAT); the role of pChAT remains unknown. We investigated the expression of pChAT and cChAT after axotomy to try to elucidate its function. In the dorsal motor nucleus of the vagus nerve (DMNV), nucleus ambiguus (NA), and hypoglossal nucleus (HN) of control rats, we observed neural expression of cChAT but no pChAT-positive neurons. Following nerve transection, we clearly detected pChAT-labeled neurons in the DMNV and weakly labeled neurons in the NA, but pChAT was not seen in the HN. In the DMNV, the mean number of cChAT-positive neurons decreased rapidly to 40.5% of control at 3 days post transection, and to 5.0% of control after 7 days. The number of cChAT-positive neurons then gradually increased and reached a plateau of about 25% of control value at 28 days post transection. pChAT-positive neurons did not appear until 7 days after transection. On the same day, pChAT mRNA was detected in the DMNV neurons by reverse transcription-polymerase chain reaction (RT-PCR) by using laser capture microdissection. The number of pChAT-positive neurons gradually decreased, and only 10% of the cholinergic neurons retained pChAT expression 56 days post transection. Double-immunofluorescence analysis showed that some of the DMNV neurons expressed both cChAT and pChAT upon recovery from axotomy. These results suggest that the expression of pChAT is associated with the regenerative or degenerative processes of motoneurons especially for general visceral efferents.

The effects of prolonged viewing of motion on short-latency ocular following responses

The adaptive effects of prolonged viewing of conditioning motion on ocular following responses (OFRs) elicited by brief test motion of a random-dot pattern were studied in humans. We found that the OFRs were significantly reduced when the directions of the conditioning and test motions were the same. The effect of conditioning motion was still observed when the speeds of the conditioning and test motions did not match. The effect was larger when the conditioning duration was longer, and decayed over time with increased temporal separation between the conditioning and test periods. These results are consistent with the characteristics of motion adaptation on the initial smooth pursuit responses. We also obtained data suggesting that the persistence of the effect depends on visual stimulation in the time between the conditioning and test periods, and that the presence of a stationary visual stimulus facilitates recovery from the motion adaptation.

Quercetin stimulates Na+/K+/2Cl- cotransport via PTK-dependent mechanisms in human airway epithelium

We investigated regulatory mechanisms of Cl(-) secretion playing an essential role in the maintenance of surface fluid in human airway epithelial Calu-3 cells. The present study reports that quercetin (a flavonoid) stimulated bumetanide-sensitive Cl(-) secretion with reduction of apical Cl(-) conductance, suggesting that quercetin stimulates Cl(-) secretion by activating an entry step of Cl(-) across the basolateral membrane through Na(+)/K(+)/2Cl(-) cotransporter (NKCC1). To clarify the mechanism stimulating NKCC1 by quercetin, we verified involvement of protein kinase (PK)A, PKC, protein tyrosine kinase (PTK), and cytosolic Ca(2+)-dependent pathways. A PKA inhibitor (PKI-14-22 amide), a PKC inhibitor (Gö 6983) or a Ca(2+) chelating agent did not affect the quercetin-stimulated Cl(-) secretion. On the other hand, a PTK inhibitor (AG18) significantly diminished the stimulatory action of quercetin on Cl(-) secretion without inhibitory effects on apical Cl(-) conductance, suggesting that a PTK-mediated pathway is involved in the stimulatory action of quercetin. The quercetin action on Cl(-) secretion was suppressed with brefeldin A (BFA, an inhibitor of vesicular transport from ER to Golgi), and the BFA-sensitive Cl(-) secretion was not observed in the presence of an epidermal growth factor receptor (EGFR) kinase inhibitor (AG1478), suggesting that quercetin stimulates Cl(-) secretion by causing the EGFR kinase-mediated translocation of NKCC1 or an NKC1-activating factor to the basolateral membrane in human airway epithelial Calu-3 cells. However, the surface density of NKCC1 was not increased by quercetin, but quercetin elevated the activity of NKCC1. These observations indicate that quercetin stimulates Cl(-) secretion by activating NKCC1 via translocation of an NKCC1-activating factor through an EGFR kinase-dependent pathway.