Orale Plattenepithelkarzinome stellen seit Jahrzehnten eine globale Herausforderung im Gesundheitswesen dar. In dieser Studie wird mit dem Optical Stretcher ein neuer diagnostischer Ansatz in der Krebserkennung der Mundhöhle untersucht und im Rahmen einer klinischen Pilotstudie evaluiert. Dabei steht die Beurteilung der viskoelastischen Eigenschaften von oralen Epithelzellen im Vordergrund. Eine entscheidende Rolle spielt hierbei vor allem das Zytoskelett einer Zelle, welches aus unterschiedlichen Faserstrukturen ein komplexes, dynamisches Gerüst bildet und für die Strukturgebung sowie für die mechanischen Eigenschaften der unterschiedlichen Zelltypen verantwortlich ist. In dieser Arbeit wurden diesbezüglich einzelne Zellen im Optical Stretcher ohne direkten mechanischen Kontakt durch zwei gegenüberliegende Laserstrahlen verformt. Dabei wurde die relative Deformation als Längenänderung entlang der Laserachse von gedehnter zu ungedehnter Zelle definiert. Die relative Deformation dient als Vergleichsparameter und unterliegt verschiedenen Einflussfaktoren. Schließlich erlauben das Maß und die Art der Deformation, welche individuell für jede Zelle sind, Rückschlüsse auf ihr biologisches Verhalten. In Kombination mit statistischen Auswertungsalgorithmen war es möglich, signifikante Unterschiede hinsichtlich der relativen Dehnung zwischen benignen und malignen oralen Zellen darzustellen. Die Ergebnisse zeigen, dass der Optical Stretcher in der Lage ist, bereits minimale Veränderungen zwischen den verschiedenen zytoskelettalen Zuständen einer Zelle zu detektieren und somit wird sich die Dehnungsfähigkeit einer Zelle zukünftig als sensibler Zellmarker zur Dignitätsbestimmung etablieren.

A systems biology approach was adopted in order to assess various aspects of the disease oral squamous cell carcinoma. Three main aims were addressed; assess the ability of CoCl2 to mimic the hypoxic response in a eukaryotic cell line, assess the role of PDE4D in oral squamous cell carcinoma (OSCC) and the construction of a normoxic/hypoxic mathematical model to identify therapeutic targets.Cancer cells often acquire a revised metabolism which aids in initiation, survival and progression of the tumour. This is predominantly due to the transcription factor HIF-1 which is activated under hypoxic conditions. Certain compounds such as cobalt chloride (CoCl2) have been used extensively to inhibit the degradation of HIF-1α and simulate hypoxia. CoCl2 is likely to have off-target effects on metabolism; these effects were examined when exposing human telomerase reverse transcriptase (hTERT) cells to 100μM CoCl2. Gas chromatography-mass spectrometry (GC-MS), liquid chromatography-mass spectrometry (LC-MS) based metabolomics were utilised in combination with ELISA assays for HIF-1α and ATP. Central metabolism was accurately mimicked when hTERT cells were subjected to 100μM CoCl2, however; it was apparent that this concentration of CoCl2 does not induce an equal extent of hypoxia as 1% oxygen. A number of off-target effects of CoCl2 were observed in secondary metabolism, specifically in lipids and fatty acids. In conclusion, CoCl2 should be used with caution as a hypoxic mimicker with the caveat that interpretation of results should be restricted to its effects on central metabolism.The transcription factor CREB has the ability to regulate approximately 4000 genes, a number of which are associated with cancer initiation and progression. Cyclic adenosine monophosphate (cAMP) is required to activate CREB and is partially regulated through its degradation via the enzyme phosphodiesterase type 4D (PDE4D). A homozygous deletion of PDE4D has been associated with OSCC; however; the exact consequence of this deletion has not been fully elucidated. PDE4D was knocked down in the OSCC cell line BicR16 and cellular proliferation, migration, resistance to ionising radiation and central metabolism was investigated using MTT, scratch, clonogenic and GC-MS, respectively. The knockdown resulted in an increase in proliferation, migration and radiation resistance suggesting the role of PDE4D as a TSG. Amino acids, cholesterol, fatty acids, carbohydrates and TCA intermediates were found to be altered in concentration.A mathematical model of glycolysis, TCA and glutaminolysis under normoxia and hypoxia was constructed through the amalgamation of two established models from the literature. New reactions, parameters and metabolite concentrations were added and unnecessary entities were deleted. COmplex PAthway SImulator (COPASI) was utilised to construct the model before validating the model using experimental data from the literature and steady state and flux analyses. Sensitivity analysis and a reduction in external glucose and glutamine were mimicked and the alterations in hypoxic and normoxic metabolism analysed. The reactions vCSII, vGS, vPGK and vGII were identified as potential therapeutic targets which may affect metabolism in hypoxia only. However, certain validation methods proved unsuccessful and hence the model requires further work before attempting the analyses again.

Magister Chirurgiae Dentium (MChD) / Oral Squamous Cell Carcinoma (OSCC) patients suffer from the terrible consequences of the disease and its treatment modalities, and as a result, their Quality of Life (QoL) and Oral Health-related Quality of Life (OHRQoL) is badly affected, especially due to functional limitation, physical disability and psychological disability that they encounter before, during and after treatment. There is a need for more research on OHRQoL of OSCC patients at various treatment intervals. The present study focused on investigating OHRQoL of OSCC patients at the post-treatment phase.

O carcinoma epidermóide da cavidade oral (CEO) é o tumor maligno mais frequente da região da cabeça e pescoço. O Chk2 (Checkpoint kinase 2) é considerado um supressor tumoral que atua na resposta celular ao dano do DNA. Entretanto, a relação do Chk2 entre CEO ainda não está compreendida. O objetivo deste estudo foi avaliar a imunoexpressão do Chk2 nos CEOs e associar sua expressão com parâmetros clínico-patológicos de importância prognóstica, incluindo a sobrevida global, sobrevida livre de doença e livre de metástase. A expressão de Chk2 foi analisada em 104 amostras de pacientes com CEO por meio da técnica de imunoistoquímica e foi positiva em 97,11% dos nossos casos com CEO, com isso, estratificamos apenas os casos de marcação positiva, e dividimo-los em alta expressão (> 66%) e baixa expressão (<66%), e excluímos os casos negativos de nossa análise, pois o número de casos com expressão negativa para Chk2 seria inclusivo para realizarmos as análises estatísticas. A positividade de Chk2 na maioria dos nossos casos sugere que o Chk2 possa estar envolvido na patogênese desses tumores, porém em nosso trabalho, a expressão de Chk2 não se associou com os parâmetros prognósticos. Não houve diferença entre a sobrevida global, sobrevivência livre de metástases e sobrevida livre de doença de acordo com a marcação de Chk2. Em conclusão, em nossos achados, o Chk2 não pode ser considerado como um biomarcador prognóstico do carcinoma de células epidermóides da cavidade oral. / Squamous cell carcinoma of the oral cavity (CEO) is the most frequent malignant tumor of the head and neck region. Chk2 (Checkpoint kinase 2) is considered a tumor suppressor that acts on the cellular response to DNA damage. However, the Chk2 relationship between CEO is not yet understood. The objective of this study was to evaluate the Chk2 immunoexpression in the CEOs and to associate their expression with clinical-pathological parameters of prognostic importance, including global survival, disease-free survival, and metastasis-free. The expression of Chk2 was analyzed in 104 samples of patients with CEO using the immunohistochemistry technique and was positive in 97.11% of our cases with CEO, with that, we stratified only the cases of positive marking, and we divided them into high expression (> 66%) and low expression (<66%), and we excluded the negative cases from our analysis, since the number of cases with negative expression for Chk2 would be inclusive for the statistical analysis. The positivity of Chk2 in most of our cases suggests that Chk2 may be involved in the pathogenesis of these tumors, but in our study, the expression of Chk2 was not associated with the prognostic parameters. There was no difference between overall survival, metastasis-free survival, and disease-free survival according to the Chk2 labeling. In conclusion, in our findings, Chk2 cannot be considered as a prognostic biomarker of oral squamous cell carcinoma.

O carcinoma epidermóide da cavidade oral (CEO) é o tumor maligno mais frequente da região da cabeça e pescoço. O Chk2 (Checkpoint kinase 2) é considerado um supressor tumoral que atua na resposta celular ao dano do DNA. Entretanto, a relação do Chk2 entre CEO ainda não está compreendida. O objetivo deste estudo foi avaliar a imunoexpressão do Chk2 nos CEOs e associar sua expressão com parâmetros clínico-patológicos de importância prognóstica, incluindo a sobrevida global, sobrevida livre de doença e livre de metástase. A expressão de Chk2 foi analisada em 104 amostras de pacientes com CEO por meio da técnica de imunoistoquímica e foi positiva em 97,11% dos nossos casos com CEO, com isso, estratificamos apenas os casos de marcação positiva, e dividimo-los em alta expressão (> 66%) e baixa expressão (<66%), e excluímos os casos negativos de nossa análise, pois o número de casos com expressão negativa para Chk2 seria inclusivo para realizarmos as análises estatísticas. A positividade de Chk2 na maioria dos nossos casos sugere que o Chk2 possa estar envolvido na patogênese desses tumores, porém em nosso trabalho, a expressão de Chk2 não se associou com os parâmetros prognósticos. Não houve diferença entre a sobrevida global, sobrevivência livre de metástases e sobrevida livre de doença de acordo com a marcação de Chk2. Em conclusão, em nossos achados, o Chk2 não pode ser considerado como um biomarcador prognóstico do carcinoma de células epidermóides da cavidade oral. / Squamous cell carcinoma of the oral cavity (CEO) is the most frequent malignant tumor of the head and neck region. Chk2 (Checkpoint kinase 2) is considered a tumor suppressor that acts on the cellular response to DNA damage. However, the Chk2 relationship between CEO is not yet understood. The objective of this study was to evaluate the Chk2 immunoexpression in the CEOs and to associate their expression with clinical-pathological parameters of prognostic importance, including global survival, disease-free survival, and metastasis-free. The expression of Chk2 was analyzed in 104 samples of patients with CEO using the immunohistochemistry technique and was positive in 97.11% of our cases with CEO, with that, we stratified only the cases of positive marking, and we divided them into high expression (> 66%) and low expression (<66%), and we excluded the negative cases from our analysis, since the number of cases with negative expression for Chk2 would be inclusive for the statistical analysis. The positivity of Chk2 in most of our cases suggests that Chk2 may be involved in the pathogenesis of these tumors, but in our study, the expression of Chk2 was not associated with the prognostic parameters. There was no difference between overall survival, metastasis-free survival, and disease-free survival according to the Chk2 labeling. In conclusion, in our findings, Chk2 cannot be considered as a prognostic biomarker of oral squamous cell carcinoma.

Orale Plattenepithelkarzinome stellen seit Jahrzehnten eine globale Herausforderung im Gesundheitswesen dar. In dieser Studie wird mit dem Optical Stretcher ein neuer diagnostischer Ansatz in der Krebserkennung der Mundhöhle untersucht und im Rahmen einer klinischen Pilotstudie evaluiert. Dabei steht die Beurteilung der viskoelastischen Eigenschaften von oralen Epithelzellen im Vordergrund. Eine entscheidende Rolle spielt hierbei vor allem das Zytoskelett einer Zelle, welches aus unterschiedlichen Faserstrukturen ein komplexes, dynamisches Gerüst bildet und für die Strukturgebung sowie für die mechanischen Eigenschaften der unterschiedlichen Zelltypen verantwortlich ist. In dieser Arbeit wurden diesbezüglich einzelne Zellen im Optical Stretcher ohne direkten mechanischen Kontakt durch zwei gegenüberliegende Laserstrahlen verformt. Dabei wurde die relative Deformation als Längenänderung entlang der Laserachse von gedehnter zu ungedehnter Zelle definiert. Die relative Deformation dient als Vergleichsparameter und unterliegt verschiedenen Einflussfaktoren. Schließlich erlauben das Maß und die Art der Deformation, welche individuell für jede Zelle sind, Rückschlüsse auf ihr biologisches Verhalten. In Kombination mit statistischen Auswertungsalgorithmen war es möglich, signifikante Unterschiede hinsichtlich der relativen Dehnung zwischen benignen und malignen oralen Zellen darzustellen. Die Ergebnisse zeigen, dass der Optical Stretcher in der Lage ist, bereits minimale Veränderungen zwischen den verschiedenen zytoskelettalen Zuständen einer Zelle zu detektieren und somit wird sich die Dehnungsfähigkeit einer Zelle zukünftig als sensibler Zellmarker zur Dignitätsbestimmung etablieren.

Made available in DSpace on 2014-12-17T15:32:25Z (GMT). No. of bitstreams: 1 AndreaFS_tese.pdf: 610478 bytes, checksum: 22934e3fba7a401686d3b0057e0e7f35 (MD5) Previous issue date: 2007-07-11 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The expression of bone morphogenetic proteins (BMPs) is altered in a variety of human canceres. The BMP-2/4 and BMPR-IA were recently shown to be overexpressed in high-risk premalignant and malignant lesions of oral epithelium. The present study analysed the expression of BMP-2/4 and BMPR-IA in Oral Squamous Cell Carcinoma (OSCC) such as their implications in disease prognostic using munohistochemistry. Ten cases of Oral Fibroepithelial Hiperplasia were selected as a control group. The experimental group included 16 cases of OSCC without metastases and 7 cases of OSCC metastatic. The presence or absence of nodal metastases was used as parameter to evaluated the disease prognostic. The results demonstrated weak immunoreactivity for BMP-2/4 and BMPR-IA in every case of the control group. In the cases of OSCC with metastases an overexpression of BMP-2/4 (71,4%) was observed while the BMPR-IA showed weak expression (85,7%). In the cases of OSCC without metastases BMP-2/4 (62,5%) and BMPR-IA showed strong immunostaining standing out an overexpression of the receptor in all the specimens. Observed statistical significance for correlation between the oral cancer prognostic and the staining intensity of the BMP-2/4 (p=0,002). There wasn t statistical significance for association between the staining intensity of the BMPR-IA and the disease prognostic (p<0,001). In conclusion, this findings suggest that the overexpression of BMP-2/4 associated with the loss of expression of the BMPR-IA in OSCC metastatic has prognostic relevance, as the loss of sensitivity to BMPs can be an indicative of metastases development in OSCC / A express?o das prote?nas morfogen?ticas ?sseas (BMPs) est? alterada em v?rios c?nceres humanos. A BMP-2/4 e o BMPR-IA foram recentemente encontrados superexpressos em les?es malignas e pr?-malignas de alto risco em epit?lio oral. Este estudo analisou a express?o da BMP-2/4 e seu receptor BMPR-IA em 23 esp?cimes de Carcinoma Epiderm?ide Oral (CEO), utilizando a imuno-histoqu?mica. O grupo controle constou de 10 casos de Hiperplasia Fibro-epitelial da mucosa oral. O grupo experimental foi constitu?do por 16 casos de CEO n?o metast?tico e 7 casos de CEO metast?tico. Utilizou-se o par?metro presen?a ou aus?ncia de met?stase nodal para avaliar o progn?stico da doen?a. Os resultados demonstraram imunorreatividade fraca para a BMP-2/4 e o BMPR-IA em todos os esp?cimes do grupo controle. No grupo experimental com met?stase, a BMP-2/4 exibiu forte expressividade (71,4%), enquanto que o BMPR-IA mostrou fraca express?o (85,7%). No grupo experimental sem met?stase, evidenciou-se forte express?o para a BMP-2/4 (62,5%) e para o BMPR-IA (100%). Encontrou-se signific?ncia estat?stica para a associa??o entre o progn?stico do CEO e a intensidade de marca??o da BMP-2/4 (p=0,002). Para o BMPR-IA n?o houve signific?ncia estat?stica ? sua associa??o com o progn?stico da doen?a (p<0,001), em fun??o do tamanho da amostra. Portanto, os resultados sugerem que a fraca expressividade do BMPR-IA associada ? forte express?o da BMP-2/4, no grupo experimental com met?stase, tem relev?ncia progn?stica, j? que a perda de sensibilidade ?s BMPs, atrav?s da perda de express?o de seus receptores pode ser indicativo de desenvolvimento de met?stase em CEO

No description available.

Background: Standardized staging procedures and presentation of oral squamous cell carcinoma (OSCC) patients in multidisciplinary tumor boards (MDTB) before treatment and utilization of elective neck dissection (ND) are expected to improve the outcome, especially in local advanced LAOSCC (UICC stages III–IVB). As standardized diagnostics but also increased heterogeneity in treatment applied so far have not been demonstrated to improve outcome in LAOSCC, a retrospective study was initiated. Methods: As MDTB was introduced into clinical routine in 2007, 316 LAOSCC patients treated during 1991-2017 in our hospital were stratified into cohort 1 treated before (n=104) and cohort 2 since 2007 (n=212). Clinical characteristics, diagnostic procedures and treatment modality of patients were compared using Chi-square tests and outcome analyzed applying Kaplan-Meier plots and log-rank tests as well as Cox proportional hazard regression. Propensity scores (PS) were used to elucidate predictors for impaired distant metastasis-free survival (DMFS) in PS-matched patients. Results: Most patient characteristics and treatment modalities applied showed insignificant alteration. Surgical treatment included significantly more often resection of the primary tumor plus neck dissection, tracheostomy and percutaneous endoscopic gastrostomy tube use. Cisplatin-based chemo-radiotherapy was the most frequent. Only insignificant improved disease- (DFS), progression- (PFS) and event-free (EFS) as well as tumor-specific (TSS) and overall survival (OS) were found after 2006 as local (LC) and locoregional control (LRC) were significantly improved but DMFS significantly impaired. Cox regression applied to PS-matched patients elucidated N3, belonging to cohort 2 and cisplatin-based chemo-radiotherapy as independent predictors for shortened DMFS. The along chemo-radiotherapy increased dexamethasone use in cohort 2 correlates with increased DM. Conclusions: Despite standardized diagnostic procedures, decision-making considering clear indications and improved therapy algorithms leading to improved LC and LRC, shortened DMFS hypothetically linked to increased dexamethasone use had a detrimental effect on TSS and OS.

Introduction: Le gène O6-méthylguanine-ADN méthyltransferase (MGMT) code pour une enzyme spécifique réparatrice de l’ADN qui protège les cellules de la toxicité des agents alkylants. Ainsi, l’activité du MGMT est un mécanisme majeur de résistance aux agents alkylants. Il a été démontré qu’une diminution de l’expression du gène MGMT par une hyperméthylation du promoteur résulte en une amélioration de la survie chez les patients avec certains types de tumeurs qui sont traitées avec des agents chimiothérapeuthique alkylants. Objectifs: Déterminer la prévalence de la méthylation du gène MGMT chez des patients avec des cancers épidermoïdes localement avancés de la sphère ORL traités avec chimioradiothérapie et évaluer l’impact de cette méthylation sur la survie. Méthodes: Sur 428 patients consécutifs, traités avec chimioradiothérapie à notre institution et suivis pour un période médiane de 37 mois, 199 spécimens chirurgicaux paraffinés ont été récupérés. L’ADN était extrait et modifié par le traitement au bisulfite. Une réaction en chaîne de la polymérase, spécifique à la méthylation était entreprise pour évaluer l’état de méthylation du promoteur du gène du MGMT. Les résultats de laboratoire étaient corrélés avec la réponse clinique. L’analyse statistique était exécutée à l’aide du test de Fisher pour les données catégoriques et à l’aide des courbes de Kaplan-Meier pour les échecs au traitement. Résultats : Des 199 extraits d’ADN initiaux, 173 (87%) étaient modifiés au bisulfite avec succès. Des ces spécimens modifiés, 71 (41%) ont démontré une hyperméthylation du MGMT. Pour les cas de méthylation et nonméthylation du MGMT, les caractéristiques des patients n’étaient pas significativement différentes. Les taux de réponse étaient 71 et 73% (p=NS) respectivement. Le contrôle locorégional était respectivement 87 et 77% (p=0.26), la survie sans maladie était 80 et 60% (p=0.38), la survie sans métastase à distance était 92 et 78% (p=0.08) et la survie globale était 64 et 62% (p=0.99) à 3 ans. Conclusions : L’état de méthylation du MGMT est fortement prévalent (41%) et semble avoir un possible impact bénéfique sur la survie quand la chimioradiothérapie est administrée aux patients avec des stades avancés de cancers tête et cou. / Background: The O6-methylguanine-DNA methyltransferase (MGMT) gene encodes a specific DNA repair enzyme that protects cells from toxicity of alkylating agents. Thus, MGMT activity is a major mechanism of resistance to alkylating drugs. It has been shown that decreased MGMT gene expression by promoter hypermethylation results in improved survival in patients with certain types of tumors that are treated with alkylating chemotherapeutic agents. Objectives: To determine the prevalence of MGMT methylation in patients with locally advanced Head and Neck Squamous Cell Carcinoma (HNSCC) treated with chemoradiation therapy and to evaluate the impact of this methylation on survival. Methods: Out of 428 consecutive patients treated with chemoradiation therapy at our institution and followed for a median of 37 months, 199 paraffin embedded biopsy or surgical specimens were retrieved. DNA was extracted and subjected to bisulfite treatment. A methylation specific PCR (MSP) was conducted to assess the methylation status of the MGMT gene promoter. Laboratory data was correlated with clinical response. Statistical analysis was performed using Fisher’s test for categorical data and Kaplan-Meier’s curves and logrank statistics for failure times. Results: From the initial 199 DNA extracts, 173 (87%) were successfully modified with bisulfite. Out of these, 71 (41%) demonstrated hypermethylation of MGMT. For MGMT methylated cases and nonmethylated cases, patients characteristics were not significantly different. Response rates were 71 and 73% (p=NS), respectively. Local control rate (LCR) was respectively 87 and 77% (p=0.26), Disease-free survival (DFS) was 80 and 60% (p=0.38), distant metastasis free survival (DMFS) was 92 and 78% (p=0.08) and overall survival (OS) was 64 and 62% (p=0.99) at 3 years respectively. Conclusions: MGMT methylation status is highly prevalent (41%) and seems to have a possible beneficial impact on survival when chemoradiation therapy is given to patients with advanced stage HNSCC.