Acquired tracheobronchomalacia developed following voice prosthesis implantation.

Acquired tracheobronchomalacia (ATBM) is a condition in which the tracheobronchial wall and cartilage progressively lose their rigidity, resulting in dynamic collapse during exhalation. In this report, we present a case of ATBM that developed following voice prosthesis implantation. To the best of our knowledge, this is the first documented case of such a condition in the medical English literature based on a PubMed search. A 63-year-old man was referred to National Kyushu Cancer Center in Japan with complaints of pharyngeal pain and a laryngeal tumor. The tumor was diagnosed as laryngeal cancer, and the patient underwent laryngectomy. Three months after the surgery, we implanted a voice prosthesis through a tracheoesophageal puncture. Two months after implantation, the patient experienced dyspnea. This condition was subsequently diagnosed as ATBM through computed tomography and bronchofiberscope examinations. After the removal of the voice prosthesis, there has been no progression of ATBM for over five years. While ATBM may not be a common occurrence in the practice of head and neck surgeons, it should be considered as a potential complication when patients report dyspnea following voice prosthesis implantation.

YAP1 is a potent driver of the onset and progression of oral squamous cell carcinoma.

Head-and-neck squamous cell carcinoma (HNSCC) is the sixth most common group of cancers in the world, and patients have a poor prognosis. Here, we present data indicating that YAP1 may be a strong driver of the onset and progression of oral SCC (OSCC), a major subtype of HNSCC. Mice with tongue-specific deletion of Mob1a/b and thus endogenous YAP1 hyperactivation underwent surprisingly rapid and highly reproducible tumorigenesis, developing tongue carcinoma in situ within 2 weeks and invasive SCC within 4 weeks. In humans, precancerous tongue dysplasia displays YAP1 activation correlating with reduced patient survival. Combinations of molecules mutated in OSCC may increase and sustain YAP1 activation to the point of oncogenicity. Strikingly, siRNA or pharmacological inhibition of YAP1 blocks murine OSCC onset in vitro and in vivo. Our work justifies targeting YAP1 as therapy for OSCC and perhaps HNSCC, and our mouse model represents a powerful tool for evaluating these agents.

Stress-triggered YAP1/SOX2 activation transcriptionally reprograms head and neck squamous cell carcinoma for the acquisition of stemness.

PURPOSE: The clinical importance of cancer stem cells (CSCs) in head and neck squamous cell carcinoma (HNSCC) is well recognized. However, a reliable method for the detection of functioning CSC has not yet been established. We hypothesized that YAP1, a transcriptional coactivator, and SOX2, a master transcription factor of SCC, may cooperatively induce stemness through transcriptional reprogramming. METHODS: We immunohistochemically examined the expression of SOX2 and YAP1 in the CD44 variant 9 (CD44v9)-positive invasion front. A CSC-inducible module was identified through a combination of siRNAs and sphere formation assays. YAP1 and SOX2 interactions were analyzed in vitro. RESULTS: The triple overexpression of SOX2, YAP1, and CD44v9 was significantly associated with poor prognosis. TCGA data revealed that the CSC-inducible module, which was related to EMT and angiogenesis, was significantly correlated with poor prognosis. The KLF7 expression, representatively chosen from the module, also correlated with poor prognosis and was essential for sphere formation and CSC propagation. Sphere stress-activated YAP1 enhanced SOX2 activity. CONCLUSIONS: The stress-triggered activation of YAP1/SOX2 transcriptionally reprograms HNSCC for the acquisition of stemness. Triple SOX2, YAP1, and CD44v9 immunostaining assays may be useful for the selection of high-risk patients with functioning CSCs, and YAP1 targeting may lead to the development of a CSC-targeting therapy.

Clinicopathological analysis of sinonasal malignant lymphoma in an HTLV-1 endemic area in Japan -special focus on primary sinonasal diffuse large B-cell lymphoma.

The present study investigated histological subtypes of lymphoma in patients newly diagnosed with malignant lymphoma in the human T-cell leukemia virus type 1 (HTLV-1) endemic area of Japan, and further analyzed the clinicopathological features and clinical outcomes of patients with primary sinonasal lymphoma. We retrospectively examined 151 patients aged 18-90 years in Fukuoka, Japan. Subtypes of lymphoma were determined according to the WHO classification. Among the 151 patients, 104 were diagnosed with malignant lymphoma, including 96 at the time of initial diagnosis. Ninety-two of the 96 lymphomas (96%) were non-Hodgkin lymphoma. Mature B-cell neoplasms comprised 78% (n = 75). Primary lymphoma of the sinonasal cavity was found in six patients (6%). The histological subtype of sinonasal lymphoma was diffuse large B-cell lymphoma (DLBCL) in all six tumors. Furthermore, overall survival was significantly different among three distinct DLBCL patient groups, including primary sinonasal lymphoma patients (p = 0.0016; 3-year overall survival: sinonasal DLBCL group, 53%; DLBCL of the CNS group, 0%; other DLBCL group, 83%). Our study suggests that primary DLBCL of the sinonasal tract is a distinct disease entity of DLBCL.

Hippo pathway controls cell adhesion and context-dependent cell competition to influence skin engraftment efficiency.

Cell competition is involved in mammalian embryogenesis and tumor elimination and progression. It was previously shown that, whereas NIH3T3 mouse fibroblasts expressing high levels of the yes-associated protein 1(YAP1) target TEA domain family (TEAD) transcription factors become "winners" in cell competitions, Madin-Darby canine kidney cells expressing activated YAP1 become "losers" and are eliminated from culture monolayers. Thus, YAP1's role in cell competitions is clearly context dependent. Here, we show that keratinocytes overexpressing a constitutively activated YAP1 mutant lose in in vitro competitions with control cells conducted in standard tissue culture dishes and undergo apical extrusion. Similarly, cells in which endogenous YAP1 is activated by NF2 knockdown become losers. The YAP1-overexpressing cells exhibit a decrease in cell-matrix adhesion because of defective expression of adhesion molecules such as fibronectin-1. Cell adhesion-mediated proliferation is also impaired. However, because of intrinsic factors, YAP1-expressing cells proliferate faster than control cells when cocultured in dishes impeding cell adhesion. In vivo, Mob1a/b-deficient (YAP1-activated) epidermis, which shows decreased expression of type XVII collagen, cannot be engrafted successfully onto donor mice. YAP1-activated skin grafts shrink away from surrounding control skin, and the epidermis peels off the basement membrane. Our data show that YAP1 activation controls cell competition in part by decreasing cell adhesion.-Nishio, M., Miyachi, Y., Otani, J., Tane, S., Omori, H., Ueda, F., Togashi, H., Sasaki, T., Mak, T. W., Nakao, K., Fujita, Y., Nishina, H., Maehama, T., Suzuki, A. Hippo pathway controls cell adhesion and context-dependent cell competition to influence skin engraftment efficiency.

Safety and efficacy of short-term oral immunotherapy with Cry j 1-galactomannan conjugate for Japanese cedar pollinosis: a randomized controlled trial.

Current allergen-specific immunotherapy (AIT) for pollinosis requires long-term treatment with potentially severe side effects. Therefore, development of an AIT that is safe and more convenient with a shorter regimen is needed. This prospective, double-blind, placebo-controlled trial randomized 55 participants with Japanese cedar pollinosis (JCP) to active or placebo groups to test the safety and efficacy of short-term oral immunotherapy (OIT) with Cry j 1-galactomannan conjugate for JCP. Mean symptom-medication score as the primary outcome in the active group improved 27.8% relative to the placebo group during the entire pollen season. As the secondary outcomes, mean medication score in active group improved significantly, by 56.2%, compared with placebo during the entire pollen season. Mean total symptom score was similar between active and placebo groups during the entire pollen season. There were no severe treatment-emergent adverse events in the active and placebo groups. Therefore short-term OIT with Cry j 1-galactomannan conjugate is safe, and effective for reducing the amount of medication use for JCP.

Hippo vs. Crab: tissue-specific functions of the mammalian Hippo pathway.

The Hippo signaling pathway is a vital suppressor of tumorigenesis that is often inactivated in human cancers. In normal cells, the Hippo pathway is triggered by external forces such as cell crowding, or changes to the extracellular matrix or cell polarity. Once activated, Hippo signaling down-regulates transcription supported by the paralogous cofactors YAP1 and TAZ. The Hippo pathway's functions in normal and cancer biology have been dissected by studies of mutant mice with null or conditional tissue-specific mutations of Hippo signaling elements. In this review, we attempt to systematically summarize results that have been gleaned from detailed in vivo characterizations of these mutants. Our goal is to describe the physiological roles of Hippo signaling in several normal organ systems, as well as to emphasize how disruption of the Hippo pathway, and particularly hyperactivation of YAP1/TAZ, can be oncogenic.

Targeting the Hippo signalling pathway for cancer treatment.

The Hippo signalling pathway monitors cell-cell contact and external factors that shape tissue structure. In mice, tumourigenesis and developmental abnormalities are common consequences of dysregulated Hippo signalling. Expression of Hippo pathway components is also frequently altered in human tumours and correlates with poor prognosis and reduced patient survival. Thus, the Hippo pathway is an attractive anti-cancer target. Here, we provide an overview of the function and regulation of Hippo signalling components and summarize progress to date on the development of agents able to regulate Hippo signalling for cancer therapy.

Massive internal jugular vein tumor thrombus derived from squamous cell carcinoma of the head and neck: two case reports.

PURPOSE: Tumor thrombosis of the internal jugular vein (IJV) is an extremely rare disease, and the reported cases have been exclusively associated with differentiated thyroid cancer. In the present study, we describe two cases of IJV tumor thrombosis originated from squamous cell carcinoma (SCC), which is the first case report. METHODS: Case 1 was a 67-year-old man diagnosed with advanced supraglottic SCC with a massive tumor thrombus in the IJV. He was treated with bio-radiotherapy followed by radical surgery. Case 2 was a 65-year-old woman who underwent radical surgery for SCC of thyroid with tumor thrombosis in the IJV. RESULTS: These cases rapidly developed local recurrences and distant metastases and died within 10 months after surgery. CONCLUSIONS: IJV tumor thrombosis originated from SCC apparently reflects extremely aggressive state of the tumor. Recognition and precaution to this condition is essential for the development of a clinically effective treatment strategy.

A case of peritoneal metastasis during treatment for hypopharyngeal squamous cell carcinoma.

BACKGROUND: Advanced head and neck squamous cell carcinomas frequently develop distant metastases to limited organs, including the lungs, bone, mediastinal lymph nodes, brain, and liver. Peritoneal carcinomatosis as an initial distant metastasis from hypopharyngeal squamous cell carcinoma is quite rare. CASE PRESENTATION: A 75-year-old man diagnosed with hypopharyngeal squamous cell carcinoma and his clinical stage was determined as T2N2cM0. Notably, the right retropharyngeal lymph node surrounded more than half of the right internal carotid artery. Concomitant conformal radiation therapy was administered for the primary hypopharyngeal lesion, and the whole neck and tumor response was evaluated at this point according to our algorithm-based chemoradioselection protocol. As the tumor responses at both the primary and lymph nodes were poor, with the right retropharyngeal lymph node in particular demonstrating mild enlargement, we performed a radical surgery: pharyngolaryngectomy, bilateral neck dissection, and reconstruction of the cervical esophagus with a free jejunal flap. Then, postoperative CRT was performed. During these therapies, the patient developed a fever and mild abdominal pain, which was associated with an increased C-reactive protein level. Contrast-enhanced computed tomography from the neck to the pelvis demonstrated mild peritoneal hypertrophy and ascites with no evidence of recurrent and/or metastatic tumor formation. We initially diagnosed acute abdomen symptoms as postoperative ileus. However, cytological examination of the refractory ascites resulted in a diagnosis of peritoneal carcinomatosis. Owing to rapid disease progress, the patient died 1.5 months after abdominal symptom onset. CONCLUSIONS: The present case is the second reported case of head and neck squamous cell carcinoma with peritoneal carcinomatosis as an incipient distant metastasis. Therefore, peritoneal carcinomatosis should be considered a differential diagnosis when acute abdomen is noted during treatment for head and neck cancers.

Temperature-dependent expression of type III secretion system genes and its regulation in Bradyrhizobium japonicum.

The genome-wide expression profiles of Bradyrhizobium japonicum in response to soybean (Glycine max (L.) Merr.) seed extract (SSE) and genistein were monitored with time at a low temperature (15 degrees C). A comparison with the expression profiles of the B. japonicum genome previously captured at the common growth temperature (30 degrees C) revealed that the expression of SSE preferentially induced genomic loci, including a large gene cluster encoding the type III secretion system (T3SS), were considerably delayed at 15 degrees C, whereas most nodulation (nod) gene loci, including nodD1 and nodW, were rapidly and strongly induced by both SSE and genistein. Induction of the T3SS genes was progressively activated upon the elevation of temperature to 30 degrees C and positively responded to culture population density. In addition, genes nolA and nodD2 were dramatically induced by SSE, concomitantly with the expression of T3SS genes. However, the deletion mutation of nodD2 but not nolA led to elimination of the T3SS genes expression. These results indicate that the expression of the T3SS gene cluster is tightly regulated with integration of environmental cues such as temperature and that NodD2 may be involved in its efficient induction in B. japonicum.

Genomic comparison of Bradyrhizobium japonicum strains with different symbiotic nitrogen-fixing capabilities and other Bradyrhizobiaceae members.

Comparative genomic hybridization (CGH) was performed with nine strains of Bradyrhizobium japonicum (a symbiotic nitrogen-fixing bacterium associated with soybean) and eight other members of the Bradyrhizobiaceae by DNA macroarray of B. japonicum USDA110. CGH clearly discriminated genomic variations in B. japonicum strains, but similar CGH patterns were observed in other members of the Bradyrhizobiaceae. The most variable regions were 14 genomic islands (4-97 kb) and low G+C regions on the USDA110 genome, some of which were missing in several strains of B. japonicum and other members of the Bradyrhizobiaceae. The CGH profiles of B. japonicum were classified into three genome types: 110, 122 and 6. Analysis of DNA sequences around the boundary regions showed that at least seven genomic islands were missing in genome type 122 as compared with type 110. Phylogenetic analysis for internal transcribed sequences revealed that strains belonging to genome types 110 and 122 formed separate clades. Thus genomic islands were horizontally inserted into the ancestor genome of type 110 after divergence of the type 110 and 122 strains. To search for functional relationships of variable genomic islands, we conducted linear models of the correlation between the existence of genomic regions and the parameters associated with symbiotic nitrogen fixation in soybean. Variable genomic regions including genomic islands were associated with the enhancement of symbiotic nitrogen fixation in B. japonicum USDA110.

Soybean seed extracts preferentially express genomic loci of Bradyrhizobium japonicum in the initial interaction with soybean, Glycine max (L.) Merr.

Initial interaction between rhizobia and legumes actually starts via encounters of both partners in the rhizosphere. In this study, the global expression profiles of Bradyrhizobium japonicum USDA 110 in response to soybean (Glycine max) seed extracts (SSE) and genistein, a major soybean-released isoflavone for nod genes induction of B. japonicum, were compared. SSE induced many genomic loci as compared with genistein (5.0 microM), nevertheless SSE-supplemented medium contained 4.7 microM genistein. SSE markedly induced four predominant genomic regions within a large symbiosis island (681 kb), which include tts genes (type III secretion system) and various nod genes. In addition, SSE-treated cells expressed many genomic loci containing genes for polygalacturonase (cell-wall degradation), exopolysaccharide synthesis, 1-aminocyclopropane-1-carboxylate deaminase, ribosome proteins family and energy metabolism even outside symbiosis island. On the other hand, genistein-treated cells exclusively showed one expression cluster including common nod gene operon within symbiosis island and six expression loci including multidrug resistance, which were shared with SSE-treated cells. Twelve putatively regulated genes were indeed validated by quantitative RT-PCR. Several SSE-induced genomic loci likely participate in the initial interaction with legumes. Thus, these results can provide a basic knowledge for screening novel genes relevant to the B. japonicum- soybean symbiosis.

Expression islands clustered on the symbiosis island of the Mesorhizobium loti genome.

Rhizobia are symbiotic nitrogen-fixing soil bacteria that are associated with host legumes. The establishment of rhizobial symbiosis requires signal exchanges between partners in microaerobic environments that result in mutualism for the two partners. We developed a macroarray for Mesorhizobium loti MAFF303099, a microsymbiont of the model legume Lotus japonicus, and monitored the transcriptional dynamics of the bacterium during symbiosis, microaerobiosis, and starvation. Global transcriptional profiling demonstrated that the clusters of genes within the symbiosis island (611 kb), a transmissible region distinct from other chromosomal regions, are collectively expressed during symbiosis, whereas genes outside the island are downregulated. This finding implies that the huge symbiosis island functions as clustered expression islands to support symbiotic nitrogen fixation. Interestingly, most transposase genes on the symbiosis island were highly upregulated in bacteroids, as were nif, fix, fdx, and rpoN. The genome region containing the fixNOPQ genes outside the symbiosis island was markedly upregulated as another expression island under both microaerobic and symbiotic conditions. The symbiosis profiling data suggested that there was activation of amino acid metabolism, as well as nif-fix gene expression. In contrast, genes for cell wall synthesis, cell division, DNA replication, and flagella were strongly repressed in differentiated bacteroids. A highly upregulated gene in bacteroids, mlr5932 (encoding 1-aminocyclopropane-1-carboxylate deaminase), was disrupted and was confirmed to be involved in nodulation enhancement, indicating that disruption of highly expressed genes is a useful strategy for exploring novel gene functions in symbiosis.

Ordered cosmid library of the Mesorhizobium loti MAFF303099 genome for systematic gene disruption and complementation analysis.

For effective exploitation of the genome sequence information of Lotus microsymbiont, Mesorhizobium loti MAFF303099, to discover gene functions, we have constructed an ordered and mutually overlapping cosmid library using an IncP broad host-range vector. The library consisted of 480 clones to cover approximately 99.6% of the genome with average insert size and overlap of 26.9 and 11.1 kbp, respectively. The genome of M. loti consists of a single chromosome and two plasmids. The chromosome (7,036,071 bp) was covered 99.68% by 445 clones with four gaps, although two clones were unstable in E. coli. The larger plasmid pMLa (351,911 bp) was completely covered by 23 clones, while the smaller pMLb (208,315 bp) was covered 98.85% by 12 clones with two gaps. We have also made ancillary plasmids to facilitate the construction of deletion mutants using derivatives of the library clones. As a pilot experiment to uncover regions which contain novel symbiotic genes, 13 deletion mutants were constructed to lack in total 180.5 kbp of the genome. All the mutants formed apparently normal nodules and supported symbiotic nitrogen fixation, however, one mutant that lacked a 5.3 kbp chromosomal region, 4,551,930-4,557,222, did not produce normal exopolysaccharides as judged by fluorescence on medium containing Calcofluor. The results supported the effectiveness of the approach to detect gene functions.