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Objective Human dental follicle cells (DFCs) are genuine precursor cells of cementoblasts and alveolar bone osteoblasts. MicroRNAs (miRNAs) represent a class of non-coding endogenous RNAs that silence gene expression post-transcriptionally. miRNA101 actively regulates the osteogenic differentiation of periodontal ligament cells. Therefore the aim of this study was to investigate the role of miRNA101 during the osteogenic differentiation in DFCs. Materials and methods DFCs were isolated, cultivated and osteogenic differentiated in differentiation medium. Total RNA including miRNAs was isolated and the expression of miRNA101 was examined by real-time RT-PCRs. The expression of miRNA101 was induced by miRNA101-mimic transfection and the gene expression of osteogenic transcription factors was obtained by real-time RT-PCRs. Moreover the induction of the osteogenic differentiation was evaluated by the activity of alkaline phosphatase. Results miRNA101 was regulated in DFCs during the osteogenic differentiation. After miRNA101-mimic transfection the alkaline phosphatase was increased and the gene expression of typical osteogenic transcription factors such as SP7 (osterix) was up-regulated. Conclusion Our results suggest that miRNA101 sustains the osteogenic differentiation of DFCs. [ABSTRACT FROM AUTHOR]

Background: To evaluate predictive clinico-pathological characteristics on outcome in head and neck melanoma (HNM) in a population-based study with particular emphasis on the prognostic effect of sentinel lymph node biopsy (SLNB), Charlson comorbidity index (CCI) and distinct tumor localisations. Methods: Here we primarily describe a retrospective multicenter population-based cohort study with 402 patients having undergone resection with curative intent of HNM between 2010 and 2017. SLNB was used in the diagnosis of 79 HNM patients. Outcome was analyzed, focusing on SLNB, CCI as well as tumor localisation. Overall survival (OAS) und recurrence free survival (RFS) was examined by uni- and multivariate analysis. Results: Histopathologically verified lymph node metastasis according to SLNB was associated with impaired RFS in HNM patients (p = 0.004). Especially in higher tumor stages, the sole implementation of SLNB improved survival significantly in the present cohort (p = 0.042). With most of the HNM being located in the face, melanoma of the scalp and neck could be linked to deteriorated patient's outcome in uni- as well as multivariate analysis (p = 0.021, p = 0.004). Conclusions: SLNB is a useful tool in predicting development of distant metastasis after HNM resection with curative intent. Especially in higher tumor stages, performing a SLNB ameliorated survival of HNM patients. Additionally, CCI as well as a distinct tumor localisations in HNM were identified as important risk factors in our population-based cohort study. [ABSTRACT FROM AUTHOR]

Background: Radiotherapy aggravates implant‐based prosthetic rehabilitation in patients with head and neck cancer. Purpose To evaluate the impact of radiation dose at implant and parotid gland site for prosthetic rehabilitation. Material and methods: The retrospective study includes 121 irradiated head and neck cancer patients with 751 inserted implants. Radiation doses on implant bed and parotid gland site were recorded by 3‐dimensional modulated radiation plans. Implant success was clinically and radiographically evaluated according to modified Albrektsson criteria and compared to treatment‐ and patient‐specific data. Results: Implant overall survival after 5 years was 92.4% with an implant success rate of 74.9%. Main reasons for implant failure were marginal bone resorption (20.9%), implant not in situ or unloaded (9.6%) and peri‐implantitis (7.5%). A mean radiation dose of 62.6 Gy was applied with a mean parotid dose of 35 Gy. Modulating radiation techniques went along with lower grades of xerostomia (p < 0.001). At implant site mean doses of 57.5, 42.0, and 32.3 Gy were recorded for oral, oropharyngeal, and hypopharyngeal/laryngeal carcinoma, respectively. Implant success inversely correlated to radiation dose at implant site. Strong predictors for implant failure in uni‐ and multivariate analysis were implant‐specific dose >50 Gy (HR 7.9), parotid dose >30 Gy (HR 2.3), bone (HR 14.5) and soft tissue (HR 4.5) transplants, bad oral hygiene (HR 3.8), nonmodulated radiation treatment planning (HR 14.5), and nontelescopic prosthetics (HR 5.2). Conclusion: Radiotherapy impedes implant success in a dose‐dependent manner at implant site. Modern radiation techniques effectively reduce xerostomia favoring implant‐based prosthetic rehabilitation. Implantation in bone grafts is more critical and telescopic‐retained overdentures should be preferred. [ABSTRACT FROM AUTHOR]

Objectives: Recently, multiple studies addressed the importance of lymph node ratio (LNR) in specifying patients' risk of disease recurrence in various malignancies. The present study examines the prognostic significance of LNR in predicting outcome of oral squamous cell carcinoma (OSCC) patients after surgical treatment with curative intent. Methods: Here, we describe a retrospective population-based cohort with 717 patients previously diagnosed with OSCC. Histopathologically verified lymph node metastasis was diagnosed in 290 patients. Among these patients, we evaluated the impact of LNR on overall survival (OAS) and recurrence-free survival (RFS) in uni- as well as multivariate analysis. Results: A median cutoff (0.055) in LNR was found to significantly predict outcome in OSCC patients. Five-year OAS was 54.1% in patients with a low LNR, whereas a high LNR was associated with a 5-year OAS of 33.3% (p < 0.001). Similar results were detected for RFS with a 5-year survival rate of 49.8% (LNR low) and 30.3% (LNR high) (p = 0.002). Results were confirmed in multivariate Cox regression which substantiated the importance of LNR in predicting survival in OSCC patients. Conclusions: LNR was shown to be an independent prognostic factor for outcome of OSCC in a population-based cohort in uni- as well as multivariate analysis. Hereby, a LNR ≥ 0.055 predicted a shorter OAS and RFS in our cohort. Clinical relevance: Besides established histopathological factors, LNR can be used as a reliable predictor of outcome in OSCC and might therefore be further applied in evaluating adjuvant treatment after resection in curative intention. [ABSTRACT FROM AUTHOR]

Background: The purpose of the study was to categorize the vitality and inflammation of resected bone of patients with medication‐related osteonecrosis of the jaw (MRONJ) and to correlate the grade of inflammation with the surgical success. Methods: This prospective study includes 44 patients with stage III MRONJ. Necrotic bone was resected in a block fashioned way. After demineralization and staining, histological analyses were performed by measuring the areas of necrotic, vital, and regenerative bone. Areas of chronic and acute inflammation were categorized as non, mild, moderate, and severe and were correlated with surgical success and parameters of inflammation in blood plasma (C‐reactive protein and leukocytes). Results: An average area of 59.0% was necrotic in the examined specimen. Vital bone was measured with an average area of 40.9%. The stage of chronic inflammation correlated with the amount of vital bone (P <.001) and the success of surgery (P =.002). If acute inflammation was dominant, chronic inflammation areas were found less while necrotic areas were observed more (P <.001). Also, the risk of relapses, wound healing disorders, and the level of C‐reactive protein were elevated if acute inflammation was severe or moderate (P =.031). Areas of bone regeneration were seen only in 11.3% of vital bone areas and occurred independently of infection stages. Conclusion: If possible, surgery should be delayed in patients with signs of severe acute inflammation. Patients may profit from prolonged pre‐operative antibiotic therapy to reduce the level of acute inflammation. [ABSTRACT FROM AUTHOR]

Objectives: Definition of implant success is unclear in prosthetic implant-based rehabilitation of head neck cancer patients. Materials and methods: Fifty-two patients with 309 inserted implants were included in this prospective observational study. Implant survival (in situ and loaded) and implant success (modified Albrektsson criteria) at 2-year follow-up were evaluated under the influence of patient- and implant-specific variables. Results: Thirty-nine patients with 234 implants finished the study. Overall implant survival after 2 years was 92.3% (216/234) with an osseointegration rate of 94% (220/234). Implant success was 78.6% (184/234). Main reasons for failure were "bone resorption > 1.7mm" (n = 27, 11.5%) and "implant not in situ or not loaded" (n = 18, 7.7%). Smoking (OR 3.1, p = 0.034), bone grafts (OR 2.4, p = 0.021) and radiation dose > 60 Gy (OR 3.8, p = 0.025) revealed as significant predictors for implant failure. Conclusion: Implant survival differs significantly from implant success in head and neck cancer patients. Implant success is mainly determined by radiographic peri-implant bone resorption. Clinical relevance: Dealing with head and neck cancer patients a higher amount of peri-implant bone resorption must be taken into account and warrants for intensified implant monitoring. [ABSTRACT FROM AUTHOR]

• Mesenchymal stem cells (MSCs) express RANK, dental follicle cells (DFCs) do not. • High concentrated denosumab reduces growth of MSCs. • Physiological concentrations of denosumab enhance osteogenic differentiation. The aim of this study was to evaluate the possible influence of denosumab and zoledronate on proliferation and osteogenic differentiation of alveolar bone stem cells. Mesenchymal stem cells (MSCs) and dental follicle cells (DFCs) were grown under osteogenic differentiation with concentrations from 0.25 μM to 10 μM (zoledronate) and to 20 μM (denosumab). Vitality was assessed after 7 days by CCK-8 Kit. Osteogenic differentiation was measured by alkaline phosphatase (ALP) assay and additionally by RT-qPCR of key enzymes COL1, RUNX2 and ALP. MSCs expressed receptor activator of NF-κB (RANK), as requirement to interact with denosumab. DFCs did not express RANK. Denosumab significantly reduced proliferation and ALP activity of MSCs in high concentrations (10 μM and 20 μM). Growth of DFCs was not influenced at all by denosumab. Zoledronate reduced proliferation of DFCs in higher concentrations (5 μM and 10 μM) (p > 0.05). Physiological and medium concentrations of denosumab (0.25 μM, 1 μM 5μM) significantly enhanced ALP activity in MSCs and COL1, RUNX2 and ALP were upregulated. Zoledronate had no effect on ALP activity in DFCs. Our evaluations suggest receptor and dose depending effects of denosumab in MSCs. High concentrations mediate toxic effects, whereas physiological and medium concentrations enhance osteogenic differentiation. [ABSTRACT FROM AUTHOR]

Background: In humans, there are four known proton‐sensing G‐Protein‐coupled receptors (pH‐GPCRs): GPR4 (GPR19), TDAG8 (GPR65, T‐cell death‐associated gene 8), OGR1 (GPR68, ovarian cancer GPCR1) and G2A (GPR132, G2 accumulation protein). They are known to be involved in sensing changes of extracellular proton concentrations in the acidic microenvironment of tumors, which leads to altered cell proliferation, migration, metastasis, immune cell function and inflammation. However, little is known about the expression of pH‐GPCRs in the skin and especially skin cancers. Aim: We studied the expression of pH‐GPCRs in selected skin cancers, that is Merkel cell carcinoma (MCC), dermatofibrosarcoma protuberans (DFSP), atypical fibroxanthoma (AFX) and pleomorphic dermal sarcoma (PDS). Methods: We did immunohistochemistry and immunofluorescence to analyse the expression of GPR4, TDAG8, OGR1 and G2A using paraffin‐embedded tissue samples (n = 4, exceptions: PDS GPR4/GPR65 n = 5, AFX GPR132 n = 3) from patients suffering from MCC, DFSP, AFX and PDS. Results: (a) GPR4 was expressed on all AFX and PDS specimens. All AFX and MCC showed a positive expression of G2A. All PDS exhibited a strong positive expression of G2A. (b) MCCs neither expressed GPR4 nor TDAG8. All DFSP showed no expression of TDAG8. (c) For any other combination of GPCR and skin disease, we found positive/negative mixed results. Conclusions: These are the first results on pH‐GPCRs in selected skin cancers. We provide evidence that these GPCRs are differentially expressed on the various types of skin cancers and that they can potentially be addressed as a therapeutic target in extensive disease. [ABSTRACT FROM AUTHOR]

Objectives: The aim of this study is to investigate the influence of prognostic biomarkers on radiosensitivity and survival of advanced head and neck squamous cell carcinomas treated by primary (chemo)radiation. Material and methods: The clinicopathological data and immunohistochemical staining of p16, c-Met, survivin, PD-1, and PD-L1 of 82 primarily (chemo)irradiated patients with head and neck squamous cell carcinoma were analyzed. Associations with local and locoregional radiation response, overall survival (OS), disease-free (DFS), and disease-specific survival (DSS) were assessed. Results: Complete tumor response was associated with increased patient age ( p = 0.007), N0-status ( p = 0.022), M0-status ( p = 0.007), and p16-positivity ( p = 0.022). High PD-L1 was associated with M0-status ( p = 0.026) and indicated tumor response to irradiation ( p = 0.057); survivin expression showed higher rates of response failure ( p = 0.073). Low PD-1 was associated with increased T-stage ( p = 0.029) and local recurrence ( p = 0.014). High PD-1 was strongly correlated with PD-L1-positive tumor infiltrating lymphocytes ( p < 0.001). Low PD-L1 showed a significant correlation with high c-Met expression ( p = 0.01). Significant predictors for unfavorable univariate survival were incomplete tumor response (DSS, p < 0.001), single radiotherapy (DSS, p = 0.002), M1-status (DSS, p < 0.001), decreased radiation dose (DSS, p = 0.014), high survivin (DSS, p = 0.045), and high c-Met (OS, p < 0.05). Survivin and c-Met also showed prognostic significance in multivariate survival analysis. Conclusions: P16 and PD-L1 indicate radiosensitivity, whereas survivin and c-Met implicate radioresistance in primarily (chemo)irradiated head and neck squamous cell carcinomas. The role of the PD-1/PD-L1 immune checkpoints in radiation response and survival merits further investigation. Clinical relevance: The findings may improve patient-specific therapy according to individual tumor characteristics. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Evaluating vascular autonomization of pedicled and microvascular free flaps for soft tissue reconstruction in the head and neck area by means of postoperative quantitative measurement of dynamic contrast values obtained with contrast-enhanced ultrasound. METHODS: 8/18 patients underwent lip reconstruction with a pedicle flap, 10 patients reconstruction of other parts of the head with a microvascular free transplant. Ultrasound examinations were conducted within the 1st postoperative week and 4 weeks after surgery. After the intravenous bolus of the ultrasound contrast agent, examinations were carried out for 30 sec without compression followed by 30 sec with compression of the vascular pedicle in bolus and flash kinetics. Digital cine loops were analyzed off-line with a quantification software (VueBox™) to determine the Rise Time (RT) between flap tissue with and without compression. RESULTS: Measurements showed increasing autonomous perfusion, independent of the vascular pedicle. No transplant was lost, but 4/10 patients with a microvascular flap and 1/8 patients with a pedicle flap developed postoperative complications. RT values for the pedicled and microvascular flaps obtained under compression differed significantly between the 1st and the 4th week (p = 0.025). CONCLUSIONS: Reliable neovascularization was achieved 4 weeks postoperatively. CEUS showed to be a useful method for assessing the degree of autonomization of pedicle and microvascular free flaps. [ABSTRACT FROM AUTHOR]

Objectives: The purpose of this study was to analyse the impact of surgical margins on tumour recurrence and survival of patients with carcinomas of the head and neck.Material and Methods: A cohort of 156 patients with primary squamous cell carcinoma of the head and neck treated by local resection with negative margins and neck dissection between 2004 and 2012 was investigated. Margin status in frozen sections and permanent paraffin tissues were analysed and compared to clinical and histopathological parameters as well as to tumour recurrence (local, regional and distant) and disease-specific survival (DSS).Results: Close margins (<5mm) on permanent sections were correlated to high-grade differentiation (p=0.070), lymphangiosis (p=0.009) and positive neck nodes (p=0.025) implicating regional and distant recurrence (p=0.001) as well as unfavorable DSS (p=0.002). Positive margins on initial frozen section analysis revised into negative margins during further surgery were the strongest predictor for local recurrence in uni- and multivariate analysis (p<0.001, hazard ratio 3.34). However, positive frozen section margins were not significantly predictive for DSS (p=0.150). Significant predictors for DSS in univariate analysis were local recurrence (p=0.026), T-stage (p=0.02), N-stage (p<0.001), grading (p=0.02) and lymphangiosis (p=0.001). Multivariate DSS analysis revealed lymph node metastasis (p=0.005) and local recurrence (p=0.017) as significant negative predictors.Conclusion: Close margins on permanent sections are associated with aggressive tumour characteristics, regional and distant metastasis implicating worse DSS. The accuracy of frozen section analysis seems limited as positive frozen section margins revised into negative margins bear a high risk of local recurrence. [ABSTRACT FROM AUTHOR]

Background: Alterations of the binding epitopes of bone morphogenetic protein-2 (BMP-2) lead to a modified interaction with the ectodomains of BMP receptors. In the present study the biological effect of a BMP-2 double mutant with antagonistic activity was evaluated in vivo. Methods: Equine-derived collagenous carriers were loaded with recombinant human BMP-2 (rhBMP-2) in a well-known dose to provide an osteoinductive stimulus. The study was performed in a split animal design: carriers only coupled with rhBMP-2 (control) were implanted into prepared cavities of lower limb muscle of rats, specimens coupled with rhBMP-2 as well as BMP-2 double mutant were placed into the opposite limb in the same way. After 28 days the carriers were explanted, measured radiographically and characterized histologically. Results: As expected, the BMP-2 loaded implants showed a typical heterotopic bone formation. The specimens coupled with both proteins showed a significant decreased bone formation in a dose dependent manner. Conclusion: The antagonistic effect of a specific BMP-2 double mutant could be demonstrated in vivo. The dose dependent influence on heterotopic bone formation by preventing rhBMP-2 induced osteoinduction suggests a competitive receptor antagonism. [ABSTRACT FROM AUTHOR]

Objective: Numerous studies analyzed lymphovascular invasion (LVI) in various malignant diseases, however, little is known about the role of lymphatic invasion (LI) as well as vascular invasion (VI) in oral squamous cell carcinoma (OSCC). The aim of this study is to illuminate the role of LI and VI in a population-based cohort study.Methods: We retrospectively analyzed 745 primarily resected OSCC patients in Eastern Bavaria for histopathologically verified LI and VI. Overall survival (OS) and recurrence-free survival (RFS) were calculated, whereas analysis was performed by uni- and multivariate statistics. Mean follow-up time was 7.4 years.Results: LI was found in 115 patients (15.4%), VI was diagnosed in 23 cases (3.1%). LI correlated significantly with distinct anatomical sites (p = 0.004), increasing pT-classification (p < 0.001), lymph node involvement (p < 0.001), higher grading (p < 0.001), advanced UICC-stages (p < 0.001) and adjuvant therapies (p < 0.001). Similar results were found for VI. Survival analysis resulted in a significantly decreased five-year OS and RFS in patients with diagnosed LI (OS: 41.1%, RFS: 38.3%) in contrast to LI-negative cases (OS: 66.8%, RFS: 59.7.7%, p < 0.001). Analogous outcomes were seen for patients with VI. Additionally, LI was identified as a predictive parameter, indicating individual patients' response to adjuvant therapies.Conclusion: This population-based cohort study underlines the unfavorable aspect of LI and VI on outcome in OSCC. Including LI and VI in existing staging systems could help to stratify patients' risk for adverse outcome and consecutively determine adjuvant treatment in malignant disease. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the prognostic effect of allogenic red blood cell transfusion (RBT) and preoperative anemia in patients with oral squamous cell carcinoma (OSCC) undergoing primary tumor resection.Methods: We retrospectively analyzed a cohort of 621 patients, diagnosed with OSCC receiving tumor resection in curative intention. Preoperative anemia and perioperative RBT were evaluated according to WHO definition. Overall survival (OAS) as well as recurrence-free survival (RFS) was evaluated in transfused and non-transfused as well as in anemic and non-anemic patients. In addition, outcome parameters were calculated for distinct amounts of perioperatively administered RBTs. Data analysis was performed by uni- and multivariate statistics. Mean follow-up time was 7.3 years.Results: Preoperative anemia was diagnosed in 29% of OSCC patients. Anemic patients displayed a significantly decreased five-year OAS (44%) in comparison to non-anemic equivalents (69%). 70% of non-transfused OSCC patients were alive after five years, whereas in case of RBT five-year OAS was 41%. These findings were substantiated by subgroup analysis in patients without preoperative anemia. For anemic patients however, no deleterious effect on survival in case of perioperative RBT was seen. Increasing numbers of received RBTs were shown to worsen outcome of OSCC patients in a dose-dependent manner.Conclusion: Preoperative anemia and RBT are significantly associated with impaired long-term outcome of patients suffering from OSCC. Future studies are needed to evaluate differentiated effects of RBTs in anemic and non-anemic OSCC patients and accordingly providing individual transfusion strategies to ameliorate outcome of patients suffering from OSCC. [ABSTRACT FROM AUTHOR]

Background: The incidence of postoperative complications after head and neck surgery is high. This study evaluated the influence of early elective tracheostomy on the incidence of postoperative pneumonia and delirium. Methods: We reviewed the data of all patients who had undergone removal of an oropharyngeal tumor and microsurgical tissue transfer at our department in a two year period. Pearson's Chi-squared test and the Fischer's exact t-test were then used to measure the influence of patients' preexisting conditions and risk factors and of early elective tracheostomy on the incidence of postoperative complications. Results: In total, 47 cases were analyzed. Patients with an endotracheal tube were ventilated for a longer time (3.4 days vs. 1.5 days) and were transferred to the regular ward later (after 6.9 days vs. 4.7 days) than patients with tracheostomy. Only 1 (2.1%) of the patients with a tracheostomy developed pneumonia in contrast to 5 intubated patients (10.6%) and only 2 patients with a tracheostomy developed postoperative delirium (9.5%) in contrast to 8 intubated patients (30.8%). Conclusion: Early primary tracheostomy in patients undergoing resection of oropharyngeal cancer seems to have numerous benefits, such as lower complication rates with regard to pneumonia and postoperative delirium and shorter duration of both mechanical ventilation and intensive care unit (ICU) stays. Further studies have to evaluate if these benefits also influence morbidity and mortality rates. [ABSTRACT FROM AUTHOR]