Enhanced cellular migration and prolonged chondrogenic differentiation in decellularized cartilage scaffolds under dynamic culture conditions.

Lesions of aural, nasal and tracheal cartilage are frequently reconstructed by complex surgeries which are based on harvesting autologous cartilage from other locations such as the rib. Cartilage tissue engineering (CTE) is regarded as a promising alternative to attain vital cartilage. Nevertheless, CTE with nearly natural properties poses a significant challenge to research due to the complex reciprocal interactions between cells and extracellular matrix which have to be imitated and which are still not fully understood. Thus, we used a custom-made glass bioreactor to enhance cell migration into decellularized porcine cartilage scaffolds (DECM) and mimic physiological conditions. The DECM seeded with human nasal chondrocytes (HPCH) were cultured in the glass reactor for 6 weeks and examined by histological and immunohistochemical staining, biochemical analyses and real time-PCR at 14, 28 and 42 days. The migration depth and the number of migrated cells were quantified by computational analysis. Compared to the static cultivation, the dynamic culture (DC) fostered migration of HPCH into deeper tissue layers. Furthermore, cultivation in the bioreactor enhanced differentiation of the cells during the first 14 days, but differentiation diminished in the course of further cultivation. We consider the DC in the presented bioreactor as a promising tool to facilitate CTE and to help to better understand the complex physiological processes during cartilage regeneration. Maintaining differentiation of chondrocytes and improving cellular migration by further optimizing culture conditions is an important prerequisite for future clinical application.

[Primary small cell neuroendocrine carcinoma of the larynx: a review of literature and case series]. / Kleinzelliges neuroendokrines Karzinom des Kopf-Hals-Bereichs: eine Übersichtsarbeit und Fallserie.

INTRODUCTION: Small cell neuroendocrine carcinoma (SCNC) of the larynx is a rare tumor entity with a 5-year overall survival (OS) of only 5 % after treatment with chemoradiotherapy. METHODS: A systematic review of the literature was performed for "SCNC" and "SCNC in head and neck". Our hospital's own electronic patient file database was investigated for patients diagnosed with a SCNC over the last 12 years. RESULTS: The effectiveness of chemoradiotherapy in SCNC is still unclear since randomized clinical trials are missing for the evaluation of standard of care treatment. Common therapy approaches are based on experiences with small cell lung cancer. 0.5 % of all SCNC occur in the head and neck region. In the last 12 years, we diagnosed 9 patients with SCNC, two of which were located in the larynx. Exemplarily, we report the case of a 29-year-old male with the initial diagnosis of a SCNC of the larynx with concurrent lymph node metastasis. This case is particularly interesting due to the young age at disease onset and the lack of major risk factors. Treatment was modified to nivolumab due to progressive disease after treatment with chemoradiotherapy. After an OS of 22 months, the patient deceased due to a tumor-associated major bleeding with airway obstruction. CONCLUSION: So far there are no clinical reports evaluating the use of nivolumab in third-line-therapy of SCNC. NTRK fusion (neurotrophic tyrosine receptor kinase gene fusion) or the folate receptor expression analysis should be considered to evaluate the potential use of a tropomyosin receptor kinase inhibitor or a folate receptor targeting therapy.

CD90 Is Dispensable for White and Beige/Brown Adipocyte Differentiation.

Brown adipose tissue (BAT) is a thermogenic organ in rodents and humans. In mice, the transplantation of BAT has been successfully used to combat obesity and its comorbidities. While such beneficial properties of BAT are now evident, the developmental and cellular origins of brown, beige, and white adipocytes have remained only poorly understood, especially in humans. We recently discovered that CD90 is highly expressed in stromal cells isolated from human white adipose tissue (WAT) compared to BAT. Here, we studied whether CD90 interferes with brown or white adipogenesis or white adipocyte beiging. We applied flow cytometric sorting of human adipose tissue stromal cells (ASCs), a CRISPR/Cas9 knockout strategy in the human Simpson-Golabi-Behmel syndrome (SGBS) adipocyte model system, as well as a siRNA approach in human approaches supports the hypothesis that CD90 affects brown or white adipogenesis or white adipocyte beiging in humans. Taken together, our findings call the conclusions drawn from previous studies, which claimed a central role of CD90 in adipocyte differentiation, into question.

NF-κB and Its Role in Checkpoint Control.

Nuclear factor-κB (NF-κB) has been described as one of the most important molecules linking inflammation to cancer. More recently, it has become clear that NF-κB is also involved in the regulation of immune checkpoint expression. Therapeutic approaches targeting immune checkpoint molecules, enabling the immune system to initiate immune responses against tumor cells, constitute a key breakthrough in cancer treatment. This review discusses recent evidence for an association of NF-κB and immune checkpoint expression and examines the therapeutic potential of inhibitors targeting either NF-κB directly or molecules involved in NF-κB regulation in combination with immune checkpoint blockade.

Incidence of anatomical variations according to the International Frontal Sinus Anatomy Classification (IFAC) and their coincidence with radiological sings of opacification.

BACKGROUND: The endonasal access to the frontal recess and sinus may be complicated by a variety of anatomical variations. Previous classifications of these variants were characterized by proper names or position information without anatomical reference. The IFAC is intended to simplify the classification of anatomical variations of the frontoethmoidal complex. The aim of this study was to analyse a representative number of sinus CT scans to assess the incidence of anatomical variations according to the IFAC and to compare the results with previous classifications. In addition, the coincidence of complex anatomical variations and radiological sings of opacification was investigated. METHODOLOGY/PRINCIPAL: Two hundred and forty-nine sinus CT scans were analysed in multiplanar reconstructions. Exclusion criteria were previous operations on the paranasal sinuses, malignant diseases, and an insufficient image quality. All anatomical variants were analysed according to the IFAC criteria. In addition, the coincidence of radiological sings of opacification and the presence of anatomical variations of the frontal recess and sinus were investigated. RESULTS: The analysis revealed Agger nasi cells in 95% of the CT scans. Supra agger cells (SACs) were detected in 49% and Supra agger frontal cells (SAFCs) in 25% of the data sets. Suprabulla cells (SBCs) were detected in 89% and Supra bulla frontal cells (SBFCs) in 27% of the scans. Supraorbital ethmoid cells (SECs) were detectable in 9% and interfrontal septal cells in 28% of the scans. Despite a partially strong narrowing of the frontal recess, no increased occurrence of radiological sings of opacification could be detected (p > 0.05). CONCLUSIONS: Anatomical variations in the frontoethmoidal area are very common. According to the IFAC criteria, in 43% of the patients, cells could be detected with pneumatization to or into the frontal sinus. The IFAC is structured more clearly compared to previous classifications due to the anatomical aspect. It represents the most consistent classification regarding surgical planning. Further studies will demonstrate the scientific and clinical value of this classification.

Somatic mutations and promotor methylation of the ryanodine receptor 2 is a common event in the pathogenesis of head and neck cancer.

Genomic sequencing projects unraveled the mutational landscape of head and neck squamous cell carcinoma (HNSCC) and provided a comprehensive catalog of somatic mutations. However, the limited number of significant cancer-related genes obtained so far only partially explains the biological complexity of HNSCC and hampers the development of novel diagnostic biomarkers and therapeutic targets. We pursued a multiscale omics approach based on whole-exome sequencing, global DNA methylation and gene expression profiling data derived from tumor samples of the HIPO-HNC cohort (n = 87), and confirmed new findings with datasets from The Cancer Genome Atlas (TCGA). Promoter methylation was confirmed by MassARRAY analysis and protein expression was assessed by immunohistochemistry and immunofluorescence staining. We discovered a set of cancer-related genes with frequent somatic mutations and high frequency of promoter methylation. This included the ryanodine receptor 2 (RYR2), which showed variable promoter methylation and expression in both tumor samples and cell lines. Immunohistochemical staining of tissue sections unraveled a gradual loss of RYR2 expression from normal mucosa via dysplastic lesion to invasive cancer and indicated that reduced RYR2 expression in adjacent tissue and precancerous lesions might serve as risk factor for unfavorable prognosis and upcoming malignant conversion. In summary, our data indicate that impaired RYR2 function by either somatic mutation or epigenetic silencing is a common event in HNSCC pathogenesis. Detection of RYR2 expression and/or promoter methylation might enable risk assessment for malignant conversion of dysplastic lesions.

Expression of Kallikrein-Related Peptidase 6 in Primary Mucosal Malignant Melanoma of the Head and Neck.

Mucosal melanomas of the head and neck (MMHN) are aggressive tumors with poor prognosis, different opposed to cutaneous melanoma. In this study, we characterized primary mucosal malignant melanoma for the expression of Kallikrein-related peptidase 6 (KLK6), a member of the KLK family with relevance to the malignant phenotype in various cancer types including cutaneous melanoma. Paraffin-embedded MMHN of 22 patients were stained immunohistochemically for KLK6 and results were correlated with clinical and pathological data. In 77.3% (17/22) of MMHN cases, positive KLK6 staining was found. Staining pattern for tumor cells showed a predominant cytoplasmic staining. However, in six cases we also observed a prominent nuclear staining. MMHN with a high KLK6 expression showed significantly better outcome concerning local recurrence-free survival (p = 0.013) and nuclear KLK6 staining was significantly associated with the survival status (p = 0.027). Overexpression of KLK6 was detected in more than 70% of MMHN and approximately 40% of tumors showed a strong expression pattern. Correlation between clinical outcome of MMHN patients and overexpression of KLK6 has not been addressed so far. Our data demonstrate for the first time increased levels of KLK6 in MMHN and strengthen the hypothesis that there might be a context-specific regulation and function of KLK6 in mucosal melanoma.

Expression of Submaxillary Gland Androgen-regulated Protein 3A (SMR3A) in Adenoid Cystic Carcinoma of the Head and Neck.

BACKGROUND: Adenoid cystic carcinoma of the head and neck (ACC) is a rare tumor entity which originates from the salivary glands. The prognosis remains poor, as the tumor tends to exhibit perineural invasion and frequently develops distant metastases. The submaxillary gland androgen-regulated protein 3A (SMR3A) belongs to a gene family producing opiorphin homologs and is physiologically secreted by salivary glands. Expression of SMR3A has been identified as an unfavorable risk factor in survival of patients with squamous cell carcinoma in the head and neck, but its value as a prognostic biomarker for ACC has not been addressed. MATERIALS AND METHODS: Tissue sections from primary ACC (n=86) and healthy glandular tissue as reference, were stained by immunohistochemistry. SMR3A expression levels were correlated with clinical and pathological features, including overall survival. RESULTS: All patients had undergone surgery and 67 received adjuvant radiotherapy. The median disease-free survival (DFS) was 37 months and the median overall survival (OS) was 75 months. Prominent SMR3A expression in tumor cells was found in 24 of 86 patients (27,9%), and was inversely correlated with a male gender (p=0.009). There was no significant correlation between SMR3A expression and DFS, metastasis-free survival or OS. CONCLUSION: Our data demonstrate for the first time decreased levels of SMR3A in ACC compared to normal glandular tissue. These data suggest a context-dependent regulation of SMR3A expression in the pathogenesis of distinct subtypes of head and neck tumors, and support the assumption that detection of SMR3A expression serves as a surrogate for aberrant differentiation into mucosal- or glandular-like cells in ACC and head and neck squamous cell carcinoma.