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1.
BMC Oral Health ; 24(1): 341, 2024 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-38493083

RESUMO

BACKGROUND: Oral squamous carcinoma (OSCC) is often diagnosed at late stages and bone erosion or invasion of the jawbone is frequently present. Computed tomography (CT) and magnetic resonance imaging (MRI) are known to have high diagnostic sensitivities, specificities, and accuracies in detecting these bone affections in patients suffering from OSCC. To date, the existing data regarding the impact of cone-beam computed tomography (CBCT) have been weak. Therefore, this study aimed to investigate whether CBCT is a suitable tool to detect bone erosion or invasion in patients with OSCC. METHODS: We investigated in a prospective trial the impact of CBCT in the diagnosis of bone erosion or invasion in patients with OSCC who underwent surgery. Every participant received a CBCT, CT, and MRI scan during staging. Imaging modalities were evaluated by two specialists in oral and maxillofacial surgery (CBCT) and two specialists in radiology (CT and MRI) in a blinded way, to determine whether a bone affection was present or not. Reporting used the following 3-point system: no bony destruction ("0"), cortical bone erosion ("1"), or medullary bone invasion ("2"). Histological examination or a follow-up served to calculate the sensitivities, specificities, and accuracies of the imaging modalities. RESULTS: Our results revealed high diagnostic sensitivities (95.6%, 84.4%, and 88.9%), specificities (87.0%, 91.7%, and 91.7%), and accuracies (89.5%, 89.5%, and 90.8%) for CBCT, CT, and MRI. A pairwise comparison found no statistical difference between CBCT, CT, and MRI. CONCLUSION: Our data support the routine use of CBCT in the diagnosis of bone erosion and invasion in patients with OSCC as diagnostic accuracy is equal to CT and MRI, the procedure is cost-effective, and it can be performed during initial contact with the patient.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Bucais , Tomografia Computadorizada de Feixe Cônico Espiral , Humanos , Carcinoma de Células Escamosas/diagnóstico por imagem , Carcinoma de Células Escamosas/patologia , Tomografia Computadorizada de Feixe Cônico , Células Epiteliais , Imageamento por Ressonância Magnética , Neoplasias Bucais/diagnóstico por imagem , Neoplasias Bucais/patologia , Estudos Prospectivos , Carcinoma de Células Escamosas de Cabeça e Pescoço , Tomografia Computadorizada por Raios X
2.
J Craniomaxillofac Surg ; 52(3): 355-362, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38368214

RESUMO

The aim of this study was to investigate the jawbone concentration of clindamycin (CLI) in patients with an osteonecrosis of the jaw (ONJ). Patients with medication-related ONJ (MRONJ) and osteoradionecrosis (ORN) with an antibiotic treatment with CLI were included. Plasma, vital and necrotic bone samples were collected. Plasma and jawbone samples were analyzed by liquid chromatography-tandem mass spectrometry. Patients with MRONJ exhibited a mean plasma CLI concentration of 9.6 µg/mL (SD ± 3.6 µg/mL) and mean concentrations of 2.3 µg/g CLI (SD ± 1.4 µg/g) and 2.1 µg/g CLI (SD ± 2.4 µg/g) in vital and necrotic bone samples, without statistical significance (p = 0.79). In patients with ORN, mean concentration in plasma was 12.0 µg/mL (SD ± 2.6 µg/mL), in vital bone 2.1 µg/g (SD ± 1.5 µg/g), and in necrotic bone 1.7 µg/g (SD ± 1.2 µg/g). Vital and necrotic bone concentrations did not differ significantly (p = 0.88). The results demonstrate that CLI concentrations are considerably lower than in plasma, but sufficient for most bacteria present in ONJ. Within the limitations of the study, it seems that CLI is a relevant alternative to other antibiotics in the treatment of ONJ because it reaches adequate concentrations in jawbone.


Assuntos
Osteonecrose da Arcada Osseodentária Associada a Difosfonatos , Conservadores da Densidade Óssea , Osteonecrose , Osteorradionecrose , Humanos , Clindamicina/uso terapêutico , Estudos Prospectivos , Osteonecrose/induzido quimicamente , Osteorradionecrose/etiologia , Arcada Osseodentária , Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/etiologia , Difosfonatos
3.
J Stomatol Oral Maxillofac Surg ; 125(3): 101725, 2023 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-38048907

RESUMO

INTRODUCTION: The aim of the study was to investigate the impact of different aminopenicillin administration routes on the antimicrobial effects of platelet-rich fibrin (PRF). METHODS: We enrolled patients undergoing treatment with amoxicillin/clavulanic acid (AMC) orally or ampicillin/sulbactam (SAM) intravenously. AMC was applied in a single oral dose (875/125 mg), or in a double oral dose (1750/250 mg), and SAM in a dose of 2000/1000 mg. Blood was obtained one hour after the intake of AMC or 15 min after the infusion of SAM ended. Antimicrobial effects were investigated in agar diffusion tests with fresh PRF, PRF stored for 24, and PRF stored for 48 h. Agar diffusion tests were performed with Escherichia coli, Staphylococcus aureus, Streptococcus pneumoniae, Haemophilus influenzae, and Porphyromonas gingivalis. Inhibition zones (IZs) around a 6 mm PRF disc were measured after 24 h. RESULTS: IZs for fresh PRF and the single oral dose of AMC were 0.0, 4.7, 15.2, 2.3, and 0.9 mm (E. coli, S. aureus, S. pneumoniae, H. influenzae, and P. gingivalis, respectively). For the double oral dose, these values were 0.0, 11.4, 20.0, 8.1, and 7.4 mm. IZs for SAM were 11.9, 18.2, 24.7, 20.3, and 22.1 mm. Differences between parenteral and oral application as well as between different oral doses were significant (p<0.0001, one-way ANOVA). DISCUSSION: The results of our study demonstrate that oral administration is a suitable route to load PRF with these drugs. This could expand the scope of PRF application to prevent infections at the surgical site, especially in an outpatient setting in which drugs are normally applied orally.

4.
Clin Oral Investig ; 27(10): 5991-5998, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37603167

RESUMO

OBJECTIVES: Different platelet-rich fibrin (PRF) protocols exist and are known to differ in resulting mechanical and bioactive properties. Centrifugation parameters may also influence drug release, in particular antibiotics, when using PRF as a bio-carrier. We thus evaluated three common protocols regarding effects on the bio-carrier properties. MATERIALS AND METHODS: In a prospective trial comprising 33 patients, we compared different protocols for PRF as a bio-carrier for ampicillin/sulbactam (SAM). Blood samples were taken shortly after a single dose of ampicillin/sulbactam (2 g/1 g) was administered to patients intravenously. PRF was obtained by centrifugation and three protocols were used: protocol A (1300 rpm, 8 min, RCF-max = 208 g), B (2300 rpm, 12 min, RCF-max = 652 g), and C (1500 rpm, 14 min, RCF-max = 276 g). The antibacterial activity of PRF was investigated against five oral species in vitro, based on agar diffusion methodology. RESULTS: The study demonstrates that a single dose of SAM is sufficient to reach high concentrations in PRF in all protocols (150 µg/ml), which is comparable to the plasma SAM concentration. Antibacterial activity was inferred from the diameter of inhibition zones seen in agar diffusion tests using PRF discs. Protocol B resulted in the largest inhibition zones. One-way ANOVA revealed statistically improved results for protocol B for some bacteria. CONCLUSIONS: The study provides valuable data on PRF antibiotic enrichment, notably SAM. A single dose of SAM is sufficient to reach clinically relevant concentrations in PRF. CLINICAL RELEVANCE: These findings potentially extend the application of PRF, for example in patients with osteonecrosis of the jaw or in oral surgery (e.g., stick bone).


Assuntos
Fibrina Rica em Plaquetas , Humanos , Sulbactam/farmacologia , Ágar , Estudos Prospectivos , Peptídeos e Proteínas de Sinalização Intercelular , Centrifugação/métodos , Antibacterianos/farmacologia , Ampicilina/farmacologia
5.
J Mater Sci Mater Med ; 34(4): 14, 2023 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-36964421

RESUMO

Present surgical situations require a bone adhesive which has not yet been developed for use in clinical applications. Recently, phosphoserine modified cements (PMC) based on mixtures of o-phosphoserine (OPLS) and calcium phosphates, such as tetracalcium phosphate (TTCP) or α-tricalcium phosphate (α-TCP) as well as chelate setting magnesium phosphate cements have gained increasing popularity for their use as mineral bone adhesives. Here, we investigated new mineral-organic bone cements based on phosphoserine and magnesium phosphates or oxides, which possess excellent adhesive properties. These were analyzed by X-ray diffraction, Fourier infrared spectroscopy and electron microscopy and subjected to mechanical tests to determine the bond strength to bone after ageing at physiological conditions. The novel biomineral adhesives demonstrate excellent bond strength to bone with approximately 6.6-7.3 MPa under shear load. The adhesives are also promising due to their cohesive failure pattern and ductile character. In this context, the new adhesive cements are superior to currently prevailing bone adhesives. Future efforts on bone adhesives made from phosphoserine and Mg2+ appear to be very worthwhile.


Assuntos
Cimentos Ósseos , Magnésio , Cimentos Ósseos/química , Fosfosserina , Óxidos , Adesivos , Fosfatos de Cálcio/química , Fosfatos , Minerais , Teste de Materiais , Microscopia Eletrônica de Varredura
6.
Clin Oral Investig ; 27(6): 3199-3209, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36864278

RESUMO

OBJECTIVES: Synthetic bone substitutes which can be adapted preoperatively and patient specific may be helpful in various bony defects in the field of oral- and maxillofacial surgery. For this purpose, composite grafts made of self-setting and oil-based calcium phosphate cement (CPC) pastes, which were reinforced with 3D-printed polycaprolactone (PCL) fiber mats were manufactured. MATERIALS AND METHODS: Bone defect models were acquired using patient data from real defect situations of patients from our clinic. Using a mirror imaging technique, templates of the defect situation were fabricated via a commercially available 3D-printing system. The composite grafts were assembled layer by layer, aligned on top of these templates and fitted into the defect situation. Besides, PCL-reinforced CPC samples were evaluated regarding their structural and mechanical properties via X-ray diffraction (XRD), infrared (IR) spectroscopy, scanning electron microscopy (SEM), and 3-point-bending testing. RESULTS: The process sequence including data acquisition, template fabrication, and manufacturing of patient specific implants proved to be accurate and uncomplicated. The individual implants consisting mainly of hydroxyapatite and tetracalcium phosphate displayed good processability and a high precision of fit. The mechanical properties of the CPC cements in terms of maximum force and stress load to material fatigue were not negatively affected by the PCL fiber reinforcement, whereas clinical handling properties increased remarkably. CONCLUSION: PCL fiber reinforcement of CPC cements enables the production of very freely modelable three-dimensional implants with adequate chemical and mechanical properties for bone replacement applications. CLINICAL RELEVANCE: The complex bone morphology in the region of the facial skull often poses a great challenge for a sufficient reconstruction of bony defects. A full-fledged bone replacement here often requires the replication of filigree three-dimensional structures partly without support from the surrounding tissue. With regard to this problem, the combination of smooth 3D-printed fiber mats and oil-based CPC pastes represents a promising method for fabricating patient specific degradable implants for the treatment of various craniofacial bone defects.


Assuntos
Implantes Dentários , Humanos , Teste de Materiais , Crânio/cirurgia , Durapatita , Cimentos Dentários , Cimentos de Ionômeros de Vidro , Fosfatos de Cálcio/química , Cimentos Ósseos/química
7.
Clin Oral Investig ; 26(12): 7033-7044, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35941396

RESUMO

OBJECTIVES: Mechanisms of wound healing are often impaired in patients with osteonecrosis of the jaw (ONJ). According to the guidelines for the treatment of this disease, early surgical intervention is indicated. However, surgery often faces complications such as wound healing disorders. The application of platelet-rich fibrin (PRF) after necrosectomy between bone and mucosa may constitute a promising approach to improve surgical results. An aspect that was not investigated until now is that PRF acts as a "bio-carrier" for antibiotics previously applied intravenously. MATERIALS AND METHODS: We investigated the antimicrobial properties of PRF in 24 patients presenting ONJ undergoing systemic antibiosis with ampicillin/sulbactam. We measured the concentration of ampicillin/sulbactam in plasma and PRF and performed agar diffusion tests. Ampicillin/sulbactam was applied intravenously to the patient 10 minutes for blood sampling for PRF. No further incorporation of patients' blood or PRF product with antibiotic drugs was obtained. Four healthy patients served as controls. RESULTS: Our results revealed that PRF is highly enriched with ampicillin/sulbactam that is released to the environment. The antibiotic concentration in PRF was comparable to the plasma concentration of ampicillin/sulbactam. The inhibition zone (IZ) of PRF was comparable to the standard ampicillin/sulbactam discs used in sensitivity testing. CONCLUSIONS: The results of our study demonstrated that PRF is a reliable bio-carrier for systemic applied antibiotics and exhibits a large antimicrobial effect. CLINICAL RELEVANCE: We describe a clinically useful feature of PRF as a bio-carrier for antibiotics. Especially when applied to poorly perfused tissues and bone such as in ONJ, the local release of antibiotics can reduce wound healing disorders like infections.


Assuntos
Fibrina Rica em Plaquetas , Humanos , Sulbactam/farmacologia , Ampicilina/farmacologia , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico
8.
J Clin Med ; 11(12)2022 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-35743574

RESUMO

Reconstruction of the donor site after radial forearm flap harvesting is a common procedure in maxillofacial plastic surgery. It is normally carried out with split-thickness or full-thickness free skin grafts. Unfortunately, free skin graft transplantation faces wound healing impairments such as necrosis, (partial) graft loss, or tendon exposure. Several studies have investigated methods to reduce these impairments and demonstrated improvements if the wound bed is optimised, for example, through negative-pressure wound therapy or vacuum-assisted closure. However, these methods are device-dependent, expansive, and time-consuming. Therefore, the application of platelet-rich fibrin (PRF) to the wound bed could be a simple, cost-effective, and device-independent method to optimise wound-bed conditions instead. In this study, PRF membranes were applied between the wound bed and skin graft. Results of this study indicate improvements in the PRF versus non-PRF group (93.44% versus 86.96% graft survival, p = 0.0292). PRF applied to the wound bed increases graft survival and reduces impairments. A possible explanation for this is the release of growth factors, which stimulate angiogenesis and fibroblast migration. Furthermore, the solid PRF membranes act as a mechanical barrier ("lubrication" layer) to protect the skin graft from tendon motion. The results of this study support the application of PRF in donor-site reconstruction with free skin grafts.

9.
JAMA Netw Open ; 4(4): e217083, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33881529

RESUMO

Importance: Squamous cell carcinoma (SCC) of the oral cavity is one of the most common tumor entities worldwide. Precise initial staging is necessary to determine a diagnosis, treatment, and prognosis. Objective: To examine the diagnostic accuracy of preoperative 18-F fluorodeoxyglucose (FDG) positron emission tomographic/computed tomographic (PET/CT) imaging in detecting cervical lymph node metastases. Design, Setting, and Participants: This prospective diagnostic study was performed at a single tertiary reference center between June 1, 2013, and January 31, 2016. Data were analyzed from April 7, 2018, through May 31, 2019. Observers of the FDG PET/CT imaging were blinded to patients' tumor stage. A total of 150 treatment-naive patients with clinical suspicion of SCC of the oral cavity were enrolled. Exposures: All patients underwent FDG PET/CT imaging before local tumor resection with selective or complete neck dissection. Main Outcomes and Measures: The accuracy of FDG PET/CT in localizing primary tumor, lymph node, and distant metastases was tested. Histopathologic characteristics of the tissue samples served as the standard of reference. Results: Of the 150 patients enrolled, 135 patients (74 [54.8%] men) with a median age of 63 years (range, 23-88 years) met the inclusion criteria (histopathologically confirmed primary SCC of the oral cavity/level-based histopathologic assessment of the resected lymph nodes). Thirty-six patients (26.7%) in the study cohort had neck metastases. Use of FDG PET/CT detected cervical lymph node metastasis with 83.3% sensitivity (95% CI, 71.2%-95.5%) and 84.8% specificity (95% CI, 77.8%-91.9%) and had a negative predictive value of 93.3% (95% CI, 88.2%-98.5%). The specificity was higher than for contrast-enhanced cervical CT imaging (67.0%; 95% CI, 57.4%-76.7%; P < .01) and cervical magnetic resonance imaging (62.6%; 95% CI, 52.7%-72.6%; P < .001). Ipsilateral lymph node metastasis in left- or right-sided primary tumor sites was detected with 78.6% sensitivity (95% CI, 63.4%-93.8%) and 83.1% specificity (95% CI, 75.1%-91.2%), and contralateral metastatic involvement was detected with 66.7% sensitivity (95% CI, 28.9%-100.0%) and 98.6% specificity (95% CI, 95.9%-100.0%). No distant metastases were observed. Conclusions and Relevance: In this study, FDG PET/CT imaging had a high negative predictive value in detecting cervical lymph node metastasis in patients with newly diagnosed, treatment-naive SCC of the oral cavity. Routine clinical use of FDG PET/CT might lead to a substantial reduction of treatment-related morbidity in most patients.


Assuntos
Linfonodos/diagnóstico por imagem , Neoplasias Bucais/diagnóstico por imagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Carcinoma de Células Escamosas de Cabeça e Pescoço/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Fluordesoxiglucose F18 , Humanos , Linfonodos/patologia , Metástase Linfática/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Boca , Neoplasias Bucais/patologia , Pescoço/diagnóstico por imagem , Esvaziamento Cervical , Estadiamento de Neoplasias , Estudos Prospectivos , Compostos Radiofarmacêuticos , Sensibilidade e Especificidade , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Adulto Jovem
10.
J Craniomaxillofac Surg ; 48(7): 685-693, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32507671

RESUMO

This study aimed to investigate the in vitro efficacy of three different SMAC mimetics for pro-apoptotic sensitization of HNSCC cells. We evaluated BV-6 in comparison to Birinapant and LCL161, for which pro-apoptotic sensitization effects have been demonstrated. Concentration-dependent response was measured for BV-6 in each cell line with an average IC50 value 8-fold lower than of aforementioned SMAC mimetics. Combination treatment of FasL (log2) and BV-6 (IC10) showed highly significant cell count reductions even in the lowest applied concentration in five cell lines (PCI-1: p = 0.0002, PCI-13: p = 0.0002, Detroit 562: p: p < 0.0001, FaDu: p < 0.0001, SCC-25: p = 0.0047). Synergistic effects (y < 1) were evident in eight out of 10 cell lines (PCI-1, PCI-9, PCI-13, PCI-68, Detroit 562, FaDu, SCC-25 and HaCaT). Annexin V assays revealed in nine cell lines very highly significant (p < 0.001) pro-apoptotic effects of BV-6. Western blots showed a heterogeneous IAP expression following SMAC mimetic treatment. Except for two cell lines, at least the cellular inhibitor of apoptosis protein 1 (cIAP1) was degraded in response to BV-6. For prospective targeted HNSCC therapy, this study identifies SMAC mimetics, particularly BV-6 as the compound with the highest pro-apoptotic potency, as promising antitumor agents.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma de Células Escamosas/tratamento farmacológico , Neoplasias de Cabeça e Pescoço , Intervenção Coronária Percutânea , Carcinoma de Células Escamosas de Cabeça e Pescoço , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proteína Ligante Fas/farmacologia , Proteína Ligante Fas/uso terapêutico , Humanos , Estudos Prospectivos
11.
Materials (Basel) ; 12(23)2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31766321

RESUMO

Mineral bone cements were actually not developed for their application as bone-bonding agents, but as bone void fillers. In particular, calcium phosphate cements (CPC) are considered to be unsuitable for that application, particularly under moist conditions. Here, we showed the ex vivo ability of different magnesium phosphate cements (MPC) to adhere on bovine cortical bone substrates. The cements were obtained from a mixture of farringtonite (Mg3(PO4)2) with different amounts of phytic acid (C6H18O24P6, inositol hexaphosphate, IP6), whereas cement setting occurred by a chelation reaction between Mg2+ ions and IP6. We were able to show that cements with 25% IP6 and a powder-to-liquid ratio (PLR) of 2.0 g/mL resulted in shear strengths of 0.81 ± 0.12 MPa on bone even after 7 d storage in aqueous conditions. The samples showed a mixed adhesive-cohesive failure with cement residues on the bone surface as indicated by scanning electron microscopy and energy-dispersive X-ray analysis. The presented material demonstrated appropriate bonding characteristics, which could enable a broadening of the mineral bone cements' application field to bone adhesives.

12.
J Craniomaxillofac Surg ; 47(10): 1589-1599, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31387829

RESUMO

Head and neck cancer, which predominantly arises from the oral mucosa, represents the sixth most common malignancy worldwide. These cancer cells can be resistant to programmed cell death triggered by extrinsic stimuli due to innate overexpression of inhibitor of apoptosis proteins (IAPs). The cellular protein second mitochondria-derived activator of caspases (SMAC) can antagonize IAP-induced caspase inhibition and thus trigger apoptosis. Here, we investigate the cell death-sensitizing effects of the SMAC mimetic LCL161 alone and in combination with Fas ligand (FasL) using a panel of six cell lines. Fas receptor (FasR) expression was analyzed by flow cytometry. Cells were treated with FasL and LCL161 alone or in combination, and cytotoxicity was measured using crystal violet assays. Annexin V and cell viability assays using zVAD-fmk and Necrostatin-1 (Nec-1) were carried out to assess the type of programmed cell death induced by LCL161. To demonstrate the sensitizing effects of LCL161, we employed the t-test to compare the effects of FasL alone and in combination with LCL161. Linear regression analysis was performed to determine initial and half maximal inhibitory concentrations (IC10 and IC50, respectively). Distinct FasR expression was detected in each cell line. Four of six cell lines were significantly sensitized to FasL by LCL161 (p < 0.05), and synergistic effects were observed (y < 1). Moreover, the initially resistant cell line SCC-25 was effectively sensitized to FasL by LCL161. Annexin V FACS analysis demonstrated apoptosis-sensitizing and apoptosis-inducing effects of LCL161 across all cell lines. Using specific cell death inhibitors (zVAD-fmk and Nec-1), we demonstrated that LCL161-initiated apoptosis could not be prevented, highlighting the proapoptotic potential of this mimetic in these cells. Our findings show the effectiveness of apoptotic sensitization of OSCC cells by LCL161 in combination with FasL, thus confirming the importance of an IAP-targeting therapeutic approach for oral squamous cell carcinoma.


Assuntos
Apoptose , Carcinoma de Células Escamosas , Neoplasias Bucais , Linhagem Celular Tumoral , Humanos , Proteínas Inibidoras de Apoptose
13.
Oncol Lett ; 18(3): 2220-2231, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31452723

RESUMO

Multidrug resistance (MDR) remains one of the major causes of suboptimal outcome following therapy in head and neck squamous cell carcinoma (HNSCC). ATP-binding cassette (ABC) transporters are overexpressed in HNSCC, which contributes to the limited effect of chemotherapeutic treatment. In addition to their named function, tyrosine kinase inhibitors (TKIs) have been revealed to impact on ABC transporter activity and expression. Therefore, the present study aimed to investigate the effects of combination therapy using different TKIs combined with cisplatin. Reverse transcription-quantitative PCR was used to characterize ABC transporter and receptor expression in 5 HNSCC cell lines treated with 3 different TKIs (pazopanib, dovitinib, nintedanib) and cisplatin. Treatment efficacy was analyzed using a crystal violet staining assay. Analysis of ABC transporter (ABCB1, ABCC1 and ABCG2) genetic alterations was performed using The Cancer Genome Atlas. Statistical analysis was conducted to evaluate the effects of mono- and combination treatment. With the exception of ABCB1, all of the investigated ABC transporters were expressed in each cell line. The additive effects of TKI + cisplatin combination treatment were observed for pazopanib in three cell lines, nintedanib in four cell lines, and were not observed for dovitinib in any of the cell lines investigated. The combination of multi-kinase inhibitors and conventional chemotherapy in HNSCC may strengthen the use of current therapeutic strategies; nintedanib appears to be the most suitable TKI for combination therapy. Further efforts are required to classify TKI efficacy with regard to cisplatin resistance.

14.
J Craniomaxillofac Surg ; 47(4): 695-703, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30826113

RESUMO

Membranes that form a mechanical barrier not only for cells but also for the bacterial flora of the oral cavity may be helpful in infection-free wound healing for guided tissue regeneration (GTR) applications in the field of oral- and maxillofacial surgery. Controlled wound healing without interference from bacterial contamination appears to be achievable in combination with surface scaffolds for bone- and soft tissue regeneration. As this has not yet been realized, we developed multilayered membranes in this study consisting of specific surface scaffolds for bone- and mucosal regeneration as well as bacteria-tight core membranes. These membranes were evaluated in terms of cell growth of osteoblast- (MG63), keratinocyte- (HaCaT), and fibroblast (L929) cell lines. Scaffolds were fabricated via melt electrospinning writing (MEW), while the core membrane was produced via film casting. All constructs were made of medical-grade poly(ε-caprolactone) (PCL). The bacteria-tightness was tested via a bacterial transmigration-assay. PCL scaffolds and core membranes alone demonstrated good cytocompatibility for all cell lines, which was even enhanced by fusing both components together. The core membrane displayed complete bacteria-tightness over two weeks. These bacteria-tight, individually-designed membranes from medical-grade PCL represent a high-potential, clinically oriented method of GTR in the field of oral- and maxillofacial surgery.


Assuntos
Engenharia Tecidual , Regeneração Tecidual Guiada , Poliésteres , Tecidos Suporte , Redação
15.
Mol Clin Oncol ; 8(3): 513-519, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29556384

RESUMO

Radiotherapy alone, or as an addition to surgery is important for the treatment of head and neck squamous cell carcinoma (HNSCC). In addition to their expression in germ cells, melanoma associated antigens-A (MAGE-A) are only expressed in malignant tissue. Notably, there is a known correlation between MAGE-A9 expression and poor prognosis in HNSCC patients. However, current knowledge regarding the function of MAGE-A9 expression, particularly in the context of irradiation, is limited. MAGE-A9 expression in 37 oral squamous cell carcinoma patents was immunohistochemically determined and analyzed for overall survival by the Kaplan-Meier log-rank test. Next, the expression of MAGE-A9 was determined by reverse transcription-quantitative polymerase chain reaction in HNSCC cell lines prior to and following irradiation with 2 Gray. The radiosensitivity of each cell line was determined using a clonogenic survival assay. There was a significantly (P=0.0468) longer overall survival in patients with a low level of MAGE-A9 expression. The median overall survival in patients with high MAGE-A9 expression was 47% compared to 73% in the group with low MAGE-A9 expression. The cell lines revealed a distinct expression pattern of MAGE-A9. Following irradiation of the cell lines, a significant enhancement of MAGE-A9 mRNA expression levels was observed. The most prominent alteration in MAGE-A9 expression was observed in the most radioresistant cell line. A high MAGE-A9 expression level correlates significantly with lower overall survival in HNSCC patients. Additionally, irradiation increased the MAGE-A9 mRNA levels in all five HNSCC cell lines, and the most resistant cell line demonstrated the greatest increase in MAGE-A9 expression following irradiation.

16.
J Craniomaxillofac Surg ; 46(4): 705-708, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29526412

RESUMO

The current surgical techniques used in cleft repair are well established, but different centers use different approaches. To determine the best treatment for patients, a multi-center comparative study is required. In this study, we surveyed all craniofacial departments registered with the German Society of Maxillofacial Surgery to determine which cleft repair techniques are currently in use. Our findings revealed much variation in cleft repair between different centers. Although most centers did use a two-stage approach, the operative techniques and timing of lip and palate closure were different in every center. This shows that a retrospective comparative analysis of patient outcome between the participating centers is not possible and illustrates the need for prospective comparative studies to establish the optimal technique for reconstructive cleft surgery.


Assuntos
Fenda Labial/cirurgia , Fissura Palatina/cirurgia , Cirurgia Bucal/estatística & dados numéricos , Fatores Etários , Alemanha , Humanos , Lactente , Padrões de Prática Médica , Cirurgia Bucal/métodos , Inquéritos e Questionários
17.
J Craniomaxillofac Surg ; 46(4): 611-616, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29459186

RESUMO

INTRODUCTION: Squamous cell carcinoma of the maxilla only constitutes a small fraction of Head and Neck Cancers. There is thereby a lack of information about frequent tumor staging and localization and their effect on patients' outcome. The main factors that influence longterm survival in HNSCC are the extent of the primary disease and recurrence rate, including local neck metastases. PATIENTS AND METHODS: In this study, clinical outcome and rates of disease recurrence in 68 surgically treated patients with maxillary SCC were evaluated in terms of primary tumor staging and localization. RESULTS: It could be demonstrated that maxillary cancer is mostly located in the posterior region of the upper jaw (70%). The rate of neck node metastasis was 35.3%, which is equivalent to the rest of the oral cavity and supports the role of elective neck dissection for patients with clinically negative neck node status. Staging, tumor differentiation, and infiltration of lymphatic structures correlated significantly with the development of local neck node metastases (r = 0.321, p = 0.01; r = 0.348, p < 0.01; r = 0.64; p < 0.01). CONCLUSION: Maxillary carcinomas exhibit similar rates of locoregional disease recurrence as the rest of the oral cavity. The existence of cervical metastases even in patients with T1 tumors supports the concept of elective neck dissection in early tumors with clinically negative neck status.


Assuntos
Carcinoma de Células Escamosas/patologia , Neoplasias Maxilares/patologia , Recidiva Local de Neoplasia/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/etiologia , Carcinoma de Células Escamosas/cirurgia , Feminino , Humanos , Metástase Linfática , Masculino , Neoplasias Maxilares/etiologia , Neoplasias Maxilares/cirurgia , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/etiologia , Estadiamento de Neoplasias , Fatores de Risco
18.
Oncol Lett ; 15(3): 4010-4016, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29467909

RESUMO

Inhibitor of apoptosis proteins, which are overexpressed in head and neck squamous cell carcinoma (HNSCC), may cause therapeutic resistance. Using SMAC mimetic compounds, including birinapant, to degrade and/or inhibit these proteins and sensitize apoptosis may enhance therapies in HNSCC. Fas expression was analyzed in nine HNSCC cell lines and one keratinocyte cell line via flow cytometry. These cell lines were treated with Fas ligand-Fc (FasL) and birinapant, a bivalent SMAC mimetic, in mono and combination therapies. Cytotoxicity was measured using a crystal violet assay. Annexin V assay was performed for detection of apoptosis. The treatment efficacy of mono and combination therapies was statistically analyzed. Nonlinear regression analysis was performed to determine the inhibitory concentration (IC10) of birinapant. Fas expression was detected in each cell line tested. Mono treatment with FasL revealed minor to no apoptotic effects in the majority of the cell lines. Crystal violet and Annexin V staining revealed increased apoptosis rates for all cell lines following incubation with birinapant in mono treatment. Combination treatment with FasL and birinapant (IC10) revealed additional and synergistic effects in eight out of the ten cell lines. To the best of our knowledge, the present study provided the first evidence of the apoptosis-sensitizing activity of combination treatment with FasL and birinapant in HNSCC cell lines.

19.
J Craniomaxillofac Surg ; 46(3): 492-497, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29311018

RESUMO

Melanoma-associated antigen A (MAGE-A) proteins are members of the cancer/testis antigens (CTA), and the expression of these proteins is almost exclusively limited to malignant cells, making them an attractive treatment target. MAGE-A expression is correlated with poor overall survival in several cancers, including head and neck squamous cell carcinoma (HNSCC). Among others, MAGE-A11 was found to be associated with resistance to different antineoplastic and targeted compounds, such as epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs). We searched The Cancer Genome Atlas (TCGA) database with a focus on MAGE-A and found that MAGE-A overexpression is a common event in HNSCC (27.5%). Furthermore, MAGE-A overexpression was correlated with significantly reduced overall survival (35.45 months vs. 64.78 months, P = 0.0173). In particular, MAGE-A11 overexpression was found in 9% of specimens. We then examined MAGE-A11 expression, the efficacy of EGFR and the EGFR mutational status and the effects of the pan-HER (human EGFR) TKIs erlotinib and afatinib in HNSCC cell lines. Next, we used a model of stable MAGE-A11 overexpression to demonstrate that MAGE-A11 impaired the efficacy of erlotinib and afatinib. In summary, our study provides evidence that MAGE-A11 contributes to erlotinib and afatinib resistance in head and neck cancer cell lines.


Assuntos
Afatinib/uso terapêutico , Antígenos de Neoplasias/fisiologia , Antineoplásicos/uso terapêutico , Cloridrato de Erlotinib/uso terapêutico , Proteínas de Neoplasias/fisiologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Carcinoma de Células Escamosas de Cabeça e Pescoço/imunologia , Humanos , Resultado do Tratamento , Células Tumorais Cultivadas
20.
Clin Oral Investig ; 22(3): 1477-1486, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29034444

RESUMO

OBJECTIVE: The objective of this study is to investigate the roles of melanoma-associated antigens (MAGEs) in the cisplatin treatment of head and neck cancer. MATERIALS AND METHODS: We assessed the efficacy of cisplatin in a set of four head and neck cancer cell lines using a crystal violet assay. The MAGE-A expression in all cell lines was measured with RT-qPCR. The correlation between MAGE-A expression and cisplatin efficacy was investigated using Spearman's correlation analysis. Furthermore, we established a cell line with stable overexpression of MAGE-A11 and determined influence on proliferation, cisplatin efficacy and cell apoptosis. In this cell line, the effects of cisplatin were assessed using either crystal violet assays or flow cytometry (Annexin V). RESULTS: For MAGE-A11, we observed the highest correlation (r = 1.000, p = 0.0417) with low cisplatin efficacy. Stable overexpression of MAGE-A11 resulted in no changes in proliferation, but in lower cisplatin cytotoxicity and lower rates of apoptosis. Also, mouse double minute 2 homolog (MDM2) expression was induced by MAGE-A11 overexpression. CONCLUSION: We provide evidence that MAGE-A11 expression contributes to cisplatin resistance in head and neck cancer. CLINICAL RELEVANCE: Our study underscores the negative predictive role of MAGE-A11 expression in head and neck cancer.


Assuntos
Antígenos de Neoplasias/metabolismo , Antineoplásicos/farmacologia , Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Proteínas de Neoplasias/metabolismo , Adulto , Idoso , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Citometria de Fluxo , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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