Dissertations / Theses on the topic 'Upper digestive tract cancer'

Socioeconomic inequality in cancer risk and incidence burden has received limited attention compared to genetic and behavioural risk factors. Where they have been studied, the temporal relationship between socioeconomic factors and cancer risk has been under explored due to the mainly cross-sectional nature of most research. Moreover, the inter-relationships of the multiple measures of socioeconomic status and, in particular, area and individual measures and their interaction with risk behaviours have also had limited attention. The overarching aim of this thesis was to investigate socioeconomic inequalities in the risk of lung and upper aero-digestive tract cancers and the relationship between this risk and socioeconomic status, area and individual based measures of socioeconomic circumstances, and behaviours such as smoking, alcohol consumption, diet and exercise. To understand and quantify the relative contribution by age, sex and tumour subtype to the socioeconomic inequalities of all cancer risk, a descriptive epidemiological study of cancer incidence in Scotland (2000-07) was undertaken. Age standardised rates per 100,000 population were calculated by direct standardisation to the European standard. A linear regression model was used to calculate the Slope Index of Inequality (SII) and Relative Index of Inequality (RII) which were employed to rank tumour and subtype contribution to all cancer risk socioeconomic inequalities by age for each sex for lung and upper aero-digestive tract (UADT) cancers separately. There were 216,305 cases excluding nonmelanoma skin cancer (all cancer) comprising 37,274 lung, 8,216 head and neck and 6,534 oesophageal cancers classified into anatomical or morphological subtypes. Socioeconomic circumstances were measured using the Scottish Index of Multiple Deprivation (SIMD). Analyses were partitioned by five-year age group and sex. RII was adapted to rank the contribution of each tumour type to all cancer socioeconomic inequalities and to examine subtype by age and sex simultaneously. The rank was defined as the proportion of all cancer socioeconomic inequality. All cancer socioeconomic inequality was greater for males than females (RII=0.366; female RII=0.279). The combination of lung and UADT socioeconomic inequalities contributed 91% and 81% respectively to all cancer socioeconomic inequality. For both sexes lung and UADT subtypes showed significant socioeconomic inequalities (P < 0.001) except oesophageal adenocarcinoma in males (P=0.193); for females, socioeconomic inequality was borderline significant (P=0.048). Although RII rank differed by sex, all lung and larynx subtypes contributed the most to all cancer socioeconomic inequality with RII rank for oral cavity, oesophagus–squamous cell and oropharynx following. For males 40-44 years old, socioeconomic inequalities increased abruptly peaking at 55-59 years. For females, socioeconomic inequalities gradually peaked 10 years later. In both sexes, the socioeconomic inequalities peak age preceded age of peak incidence. This study showed that socioeconomic inequalities in lung and UADT cancers vary greatly by age, tumour subtype and sex; these variations were likely to largely reflect differences between the sexes in risk behaviours which vary by birth cohort and are socioeconomically patterned. Longitudinal data enabled exploration of the temporal relationship between socioeconomic status and cancer incidence. An investigation of several individual and a single area-based measure of socioeconomic circumstances was undertaken in the second study of this thesis. The effect of country of birth, marital status, one area socioeconomic circumstances measure (Carstairs) and five individual socioeconomic variables (economic activity, education, occupational social class, car ownership, household tenure) on the risk associated with lung, UADT and all cancer combined (excluding non-melanoma skin cancer) were explored. A linked dataset using the Scottish Longitudinal Study and Scottish Cancer Registry was created to follow 203,658 cohort members aged 15+ years from 1991-2006. Relative risks (RR) were calculated using Poisson regression models by sex offset for person-years of follow-up. There were 21,832 first primary tumours (including 3,505 lung and 1,206 UADT cancers). Regardless of cancer, economic inactivity (versus activity) was associated with increased risk (male: RR 1.14 95% CI 1.10, 1.18; female: RR 1.06 95% CI 1.02, 1.11). For lung cancer, area deprivation remained significant after full adjustment suggesting that the area deprivation cannot be fully explained by individual variables. Not having a qualification (versus degree) was associated with increased lung cancer risk; likewise for UADT cancer risk (females only). Occupational social class associations were most pronounced and elevated for UADT risk. No car access (versus ownership) was associated with increased risk (excluding all cancer risk for males). Renting accommodation (versus home ownership) was associated with increased lung cancer risk, UADT cancer risk for males only and all cancer risk for females only. Regardless of cancer group, elevated risk was associated with no education and living in deprived areas. This study demonstrated that different and independent socioeconomic variables were inversely associated (greater incidence with lower socioeconomic circumstances) with different cancer risks in both sexes; no one socioeconomic variable had a dominant risk association or captured all aspects of socioeconomic circumstances or the full life-course. The association of multiple socioeconomic variables was likely to reflect the complexity and multifaceted nature of low socioeconomic circumstances as well as the various roles of these dimensions over the life-course. A final study investigated the role of behaviours (smoking, alcohol, diet and exercise) on the association of low socioeconomic circumstances with all cancer risk and lung and upper aero-digestive tract cancers combined (LUADT). The Scottish Cancer Registry and Scottish Health Survey data were linked to create a population study (1995-2011). There were 42,983 adults over 16 years old who were followed for 3,750,611 person-years. There were 2,130 first primary cancers diagnosed including 453 LUADT cancers. Poisson regression models, minimally adjusted by age and sex, were developed to estimate the risk association between five individual socioeconomic variables (economic activity, highest qualification, occupational social class, car ownership and housing tenure), one area-based socioeconomic indicator (SIMD) and all cancer and LUADT cancer. A further socioeconomic indicator was developed to reflect multiple low socioeconomic circumstances. This was defined as the count, at the individual participant level, of socioeconomic variables in the highest risk category. A similar multiple high risk behaviour derived variable, defined as the count of highest risk category for the following variables: current smoking status, units of alcohol consumed in a week, daily fruit and vegetable consumption and exercise sessions per week, was also calculated at the individual participant level. The minimally adjusted Poisson models were successively adjusted for behaviours (smoking, alcohol, diet and exercise) to establish any remaining contribution to cancer risk not explained by behaviour. Multiple low socioeconomic circumstances were very strongly associated with increased risk for both cancer groups. For all cancer risk, the elevated risk was nearly fully attenuated for all categories of multiple low socioeconomic circumstances when adjusted for smoking only. For LUADT cancer and in the minimally adjusted model, the risk increased in a dose-response manner.
The risk associated with LUADT cancer for study participants in the highest category of multiple low socioeconomic circumstances was more than three-times greater when compared to their affluent counterparts (RR 3.35 95% CI 2.26, 4.97); this elevated risk remained at 86% compared to those with no socioeconomic disadvantage, even after full adjustment for smoking, alcohol, diet and exercise behaviours. When looking at single socioeconomic status (SES) indicators, only those who rented accommodation from a local authority remained at a 50% increased risk of LUADT cancer even after adjustment for all the behaviours (RR 1.50 95% CI 1.05, 2.16). This study demonstrated that smoking is a major inequality issue and a significant cancer risk which is socially patterned. Further analytical research is required to fully understand the pathways and mechanisms between socioeconomic circumstance and lung and upper aerodigestive cancer risk.

The incidence and mortality rates of cancers of upper aero-digestive tract (UADT) remain significantly high in India. These cancers, which occur more commonly in later adulthood, are influenced by social and lifestyle behaviours carried out during childhood, adolescence and early adult life. Thus, life-course epidemiology attempts to assess varying health effects of various risk factors, according to timing, duration and frequency of exposure, which may give important clues to the causes of cancer. These cancers have serious impacts on quality of life (QoL) as they involve anatomical structures essential for mastication, speaking, cosmetic appearance and psychological wellbeing. Moreover, these cancers frequently present late and progress rapidly. Therefore, there is a need to develop a model for cost-effective screening and detection of individuals at high-risk of these cancers in the near future as well as early detection of cancer cases. Thereby, a study was designed with the following hypotheses:  Early age at initiation, frequency and duration of use of tobacco in its all forms, exposure to second hand tobacco smoke (SHS) at home and drinking alcohol has a linear dose-response relationship with the incidence of UADT cancers.  There is an association between tobacco, alcohol drinking, diet, oral hygiene and anthropometry measures with incidence of oral cancers.  Cancer site, staging, gender and age at diagnosis have an impact on QoL.  A risk-factor based screening model for UADT cancers has strong predictive ability to detect high-risk individuals. A bi-centre hospital-based frequency matched case-control study was conducted in Pune, Maharashtra State, India, from June 2014 and May 2015. Cases were histopathologically confirmed new cases of squamous cell carcinoma of UADT. Controls were patients diagnosed with a disease other than UADT or any other cancer, selected from the same hospital during the same period as the cases were recruited. Data were collected by medical-record abstraction, face-face interviews and by visual inspection of the oral cavity. A closed-ended questionnaire with a life-course perspective was used to collect patient‟s self-reported information on sociodemographics, lifestyle habits (chewing and smoking tobacco, drinking alcohol, SHS, oral hygiene) and QoL. The interviewer recorded anthropometry measures and number of missing teeth. Unconditional logistic regression was used to estimate the odds ratios (ORs) and their corresponding 95% confidence intervals (CIs). A reciever-operater characterstic curve was plotted against sensitivity and false-positive rate to produce a cut off point for the presence of UADT cancers. Examination of all QoL domains was done using oneway analysis of variance and the Bonferroni adjustments for post-hoc comparisons. Data were analysed by the Statistical Package for Social Sciences version 22. A total of 480 patients participated in the study. Chewing tobacco emerged as the strongest predictor for UADT cancers (OR=7.61; 95% CI 4.65-12.45) followed by smoking and drinking alcohol. Exposure to SHS during childhood (<16 years) rather than after ≥16 years increased the risk significantly (OR=4.05; 95% CI 2.06-7.95). There is a linear dose-response relationship between duration, frequency and early age at initiation for lifestyle risk factors (chewing and smoking tobacco; drinking alcohol) with incidence of UADT cancers in adulthood. Combined effects of tobacco and alcohol consumption habits elevated the risk (OR=12.05; 95% CI 4.61-31.49) in comparison to never users of these habits. Furthermore, the combination of these three lifestyle risk factors accounted for 86.82% of population attributable risk. Overall, the most affected QoL domains were anxiety and mood both among cases and controls. Oropharynx and hypopharynx cancer cases had the worst mean scores across all QoL domains. Stage IV cancer patients showed the worst QoL. Amongst UADT cancers in Pune, cancer of the oral cavity was the most common. Chewing tobacco showed higher odds (OR=8.51; 95% CI 4.90-14.77) for oral cancer risk as compared to UADT cancers. Poor oral hygiene emerged as significant predictor for oral cancer risk (OR=6.98; 95% CI 3.72-13.05). A screening model was derived for detection of individuals at high-risk for UADT cancers. This model has high sensitivity (93.5%), specificity (71.1%), false positive rate (28.8%), false negative rate (6.4%), positive predictive value (74.8%) and negative predictive value (96.6%). Our research recognises the framework of life-course influences of early exposure to behavioural risk-factors as independent and combined predictors of UADT cancers. The significantly compromised QoL in UADT cancer needs to be incorporated as an outcome measure in an individualized approach to therapeutic and palliative care planning of these cases to enable a better quality of survival. If validated in other studies, our proposed screening model can be applicable to many other high-risk UADT cancer populations with behavioural risk factors similar to our study population.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Dentistry and Oral Health and Menzies Health Institute Queensland
Griffith Health
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Cancers of the upper aero-digestive tract (UADT) rank as the fifth most common neoplastic disease worldwide. Two identified risk contributors are consumption of tobacco and alcohol. Among all other potential etiological factors, diet has long been recognized to play an important role in the development of cancers of the UADT. Data from a multi-centre, hospital-based case-control study conducted in Brazil were used to assess the association of dietary intake with the risk of cancers of the UADT. Dietary assessment was made in terms of estimated intake of nutrients, specific foods and food groups. After adjusting for the effects of alcohol and tobacco consumption as well as empirical confounders, protective effects against cancer of the mouth (Odds Ratio (OR) = 0.61, 95% confidence interval (95% CI): 0.4--1.0) and the pharynx (OR = 0.51, 95%CI: 0.3--0.9) were found for consumption of citric fruits. (Abstract shortened by UMI.)

Malignancies of the upper aero-digestive tract are a major public health problem, especially in South Asia. The major risk factors in South Asia remain smoked/smokeless tobacco, areca nut, alcohol abuse and poor diet, with limited evidence for human papillomavirus (HPV). Although HPV-associated head and neck squamous cell carcinoma (HNSCC) is well documented in the western world, studies on South Asian populations are few and inconsistent. However, the incidence of HPV-associated head and neck cancer (HNC) has increased in recent years. Certain high-risk types of HPV infection are regarded as well-established risk factors for cervical cancer and a subset of HNSCC; however, their true role and importance in the progression of HNSCC remain unclear. Although HPV-associated HNC patients generally have a better prognosis than those with HPV-negative disease, current chemo- and radio-therapies are largely non-specific and have considerable toxicities. RNA interference (RNAi), which has shown great promise as a highly specific therapy for other diseases, has potential for treating HPV-associated HNC, especially if disease progression is dependent on the continual expression of HPV oncogenes.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Dentistry and Oral Health
Griffith Health
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INTRODUCTION The dietary pattern approach is useful to study the effect of the overall diet on health outcomes, through considering the network of complex interactions between foods or nutrients. The main methods traditionally used to identify dietary patterns are principal components analysis, factor analysis, principal components factor analysis and cluster analysis. Latent class analysis (LCA) is a latent variable approach, that has some advantages in comparison to the previous methods. Unlike principal component, factor and principal component factor analysis, it can be used to classify individuals into mutually exclusive groups conceived as dietary patterns and differently from cluster analysis, which has the same aim of grouping subjects, it permits quantification of the uncertainty of class membership, and assessment of goodness of fit. Moreover, it allows for adjustment for covariates directly in the pattern identification. OBJECTIVES As latent class analysis has rarely been applied in dietary pattern studies, the aim of this research is to apply the recent developments of the techniques to this area of research. We targeted to address the issue of dietary pattern identification in the case-control setting using latent class analysis and latent class trees. We provided estimation of pattern sizes and their characterization, taking into account correlations between dietary variables (local dependencies), and covariate adjustment. We also evaluated the robustness of the identified dietary patterns to total non-alcoholic energy intake adjustment, for different types of correction. Finally, we illustrated the method’s properties in the assessment of the relation between the identified dietary patterns and selected health outcomes, given the all the above. DIETARY PATTERNS AND THE RISK OF ORAL AND PHARYNGEAL CANCER We analyzed data from a multicentric case-control study on oral and pharyngeal cancer (OPC) carried out between 1992 and 2009, including 946 cases and 2492 hospital controls. Information on diet was collected through a food frequency questionnaire (FFQ). Using LCA, we identified 4 dietary patterns, conceived as mutually exclusive groups of people who shared a common dietary behaviour within groups. The first pattern, labelled ‘Prudent pattern’, showed higher probability of consuming more leafy and fruiting vegetables, citrus fruit and all other kinds of fruits, tea while showing lower probability of consuming red meat. The second pattern, that we named ‘Western pattern’, reported higher consumption of red meat and lower consumption of fruits, cruciferous and fruiting vegetables. We termed the third pattern ‘Lower consumers-combination pattern’ as people in it were less likely to eat fruits, leafy and fruiting vegetables, pulses, potatoes, fish, white and red meat, bread and tea/decaffeinated coffee. The last pattern had higher probability to eating fruiting, leafy and other vegetables, white and red meat and bread, while showed a lower probability to consume coffee, tea, processed meat, cheese, fish, sugary drinks and desserts. We called this last pattern ‘Higher consumers-combination pattern’. Dietary patterns were adjusted for total non-alcoholic energy intake and correlation between certain foods item (sugar-coffee, soups-pulses) was allowed during classes identification. Compared to the Prudent pattern, the Western and the Lower consumers-combination ones were positively related to the risk of OPC (OR=2.56, 95% CI: 1.90 – 3.45 and OR=2.23, 95% CI: 1.64 – 3.02). Higher consumers-combination pattern didn’t differ significantly from the Prudent pattern (OR=1.28, 95% CI: 0.92 – 1.77). ENERGY INTAKE ADJUSTMENT IN DIETARY PATTERN RESEARCH USING LATENT CLASS ANALYSIS Using data from the multicentric case-control study on OPC (Italy, 1992-2009), we identified and compared dietary patterns adjusting or not for total non-alcoholic energy intake in the classes identification phase of the analysis. Three possible ways to correct for total energy intake in class identification were presented, corresponding to different hypothesis on the effect of this variable. In general unadjusted and adjusted solutions were comparable. The main difference was related to the patterns that showed highest/lowest non-alcoholic energy intake, that resulted in a variation of number of classes (4/5/7 patterns for the different adjusted solutions and 5 patterns for the unadjusted one). Then, to determine the effect of adjustment in predicting an health outcome, we compared the effect of unadjusted dietary patterns, unadjusted dietary patterns with non-alcoholic energy intake variable also included in the model as a confounder, and adjusted dietary patterns on the risk of OPC . Differences in the estimations for the distinct solutions were found when Odds Ratios (ORs) were not corrected for known/potential risk factors. In general, adjustments for non-alcoholic energy intake results in a mitigation of the effects, thus remaining in the same order. When adjusting for known/potential risk factors, estimations of ORs and related confidence intervals (CIs) remained consistent in all the models we fitted. In the end, specific suggestions on how to perform energy correction in dietary patterns research using LCA were delivered, basing on the results of the current analysis. DIETARY PATTERNS INSPECTION THROUGH LATENT CLASS TREE We analyzed data from two Italian case–control studies, the first included 946 cases with OPC and 2492 hospital controls, and the second included 304 cases with squamous cell carcinoma of the esophagus (ESCC) and 743 hospital controls. In our application of latent class analysis on the combined dataset of the two case-control studies (Italy, 1992-2009), we found the best fit for a solution that was difficult to interpret and included minor differences between clusters. To address these issues, the Latent Class Tree method was proposed. Three fit statistics (AIC, AIC3, BIC) were used for their different level of penalty that resulted in different lengths of the tree and consequently, different granularity in the analysis. For the first split we allowed for a 4-class solution which identified a pattern characterized by high intake of leafy and fruiting vegetable and fruits (‘Prudent pattern’), a pattern with a high intake of red meat and low intake of certain fruits and vegetables (‘Western pattern’) and two patterns which showed a combination-type of diet. The first ‘combination’ pattern showed a low intake of the majority of foods (‘Lower consumers-combination pattern’), and the other one high intake of various foods (‘Higher consumers-combination pattern’). Compared to the Prudent pattern, the Western one was positively related to OPC (OR=1.91, 95% CI: 1.41-2.58) and to ESCC (OR=3.22, 95% CI: 1.78 – 5.82). The Lower consumers-combination pattern was positively associated to OPC (OR=2.14, 95% CI: 1.58-2.91) and to ESCC (OR=2.85, 95% CI: 1.47-5.55). No significant association was found between the Higher consumers-combination pattern and OPC (1.04, 95% CI: 0.74-1.46) and ESCC (OR=0.89, 95% CI: 0.39-1.99). In the ‘Prudent pattern’ branch of the tree, at the third level, we found two classes that differed in the risk of both cancer types. These two classes differed mainly for the intake of citrus fruit, showing respectively, OR=1.85, 95% CI:1.07-3.19 for OPC and OR=5.37, 95% CI: 1.48-19.44 for ESCC for the class that reported low intake of citrus fruit with respect to the class which exhibit a high intake of citrus fruit. No other significant differences were found between the other pairs of classes at any other level of the tree. CONCLUSION We presented latent class methods as powerful tools to determine dietary patterns conceived as mutually exclusive homogeneous groups of subjects which shared common dietary habits. These methods exhibit some advantages, with respect to classical approaches, that can address important issues in dietary pattern research. For example, it is possible to obtain estimation for pattern prevalence in the population, and to perform energy intake adjustment in the pattern identification phase of the analysis. Moreover, class formation inspection, comparison between different solutions and the analysis of subgroups that may be relevant for the research at hand are features offered by the newly developed latent class tree approach.

Introdução: O câncer das Vias Aéreas e Digestivas Superiores compreendem um grupo de tumores que se distribuem por diversas regiões anatômicas. Para a maioria das localizações os principais fatores de risco são o tabaco e o álcool. Como os fatores de risco são conhecidos espera-se que as diversas campanhas de prevenção e detecção precoce estivessem propiciando à diminuição da incidência. Objetivos Estimar em algumas localidades do mundo as tendências da incidência dos tumores de lábio, língua, boca, glândulas salivares, orofaringe, nasofaringe e hipofaringe de 1969 a 1999. Métodos Analisou-se os coeficientes de incidência de 18 Registros de Câncer de Base Populacional que possuíam toda a série histórica publicada no “Cancer Incidence in Five Continents”.utilizando-se modelos de regressão polinomial.Resultados Houve tendência de aumento, estatisticamente significativo, para o câncer de língua e boca em São Paulo em mulheres e em homens de diversos países europeus e localidades dos EUA. Em contrapartida houve queda em Porto Rico, Mumbai e Cingapura. O câncer de lábio decresceu na maioria das localidades em homens. Entretanto em países do norte da Europa e em Iowa houve aumento em mulheres. O câncer de orofaringe aumentou em homens na Europa e em Iowa e decresceu em Cali, Quebec, e localidades da Ásia. O câncer de hipofaringe apresentou tendência crescente em várias localidades da Europa em homens e queda na Suécia, Inglaterra, Cingapura e Porto Rico. Conclusão os tumores de língua, boca e orofaringe continuam apresentando tendências de crescimento para diversas localidades. Por isso há a necessidade de campanhas propiciando a prevenção e a detecção precoce.
Introduction: Upper Aerodigestive Tract Cancer comprises a group of neoplasms which spread over many anatomic regions. Considering most of the locations, the worst risk coefficients are tobacco and alcohol. Taken the coefficients are known, prevention and precocious detection campaigns are expected to lessen the incidence statistics. Objectives. To estimate the trends on lip, oral cavity (tongue and mouth), salivary gland, oropharyngeal, nasopharyngeal and hypopharyngeal cancer incidences in some locations worldwide between 1969 - 1999. Methods Incidence coefficient data of eighteen records from the Population Database Cancer Registry which had its history published in “Cancer Incidence in Five Continents” has been analysed applying polynomial regression models. Results There has been a statistically significant increase to the number of oral cavity cancer in Sao Paulo among women; in European countries as well as in some North American cities, the increase was detected among both men and women. On the other hand, there has been a decrease in Puerto Rico, Mumbai and Singapore. The incidence of lip cancer decreased in most locations (among men). However, an increase has been detected in North Europe and in Iowa, USA (among women). Oropharyngeal cancer has increased in number among men in Europe and Iowa, USA; it decreased in number in Cali, Quebec, and other areas in Ásia. Hypopharyngeal cancer has shown to be an increasing trend in many Europeans countries among men, but a decreasing one in Sweden, England, Singapore and Puerto Rico. Conclusion Oral cavity and oropharyngeal neoplasms trends proceed grow in many locations. Finally, the need for prevention and precocious detection campaigns is urgent.

Contexte : L’amiante est maintenant une cause avérée de cancer du larynx, mais le rôle des expositions professionnelles dans la survenue des cancers des voies aéro-digestives supérieures (VADS) reste largement méconnu. Bien que plusieurs études aient rapporté des associations entre les expositions professionnelles et ces cancers, il est difficile de synthétiser les résultats et d’en tirer des conclusions définitives. Objectifs : (1) Le premier objectif est de synthétiser les données épidémiologiques disponibles sur les associations entre les cancers de la cavité buccale, du pharynx et du larynx (les cancers des VADS les plus fréquents) et les expositions professionnelles ; (2) le second objectif est, à partir des données d’une large étude cas-témoins, l'étude Icare, d'identifier les professions ou industries présentant des risques élevés de cancer des VADS, puis d'étudier le rôle de certaines expositions professionnelles suspectées (amiante, laines minérales (LM), poussières de ciment, silice). Matériel et méthodes : (1) Une recherche bibliographique et des séries de méta-analyses ont été réalisées pour certaines expositions professionnelles suspectées. (2) L'étude Icare est une étude cas-témoins en population générale française incluant 2415 cas de cancer des VADS et 3555 témoins. L'historique professionnel complet des sujets a été recueilli, avec une description détaillée de chaque emploi exercé. L'évaluation des expositions à l'amiante, aux LM, aux poussières de ciment et à la silice sur l’ensemble de la vie professionnelle a été réalisée à l'aide des matrices emplois-expositions développées dans le cadre du programme Matgéné (Institut de Veille Sanitaire). Résultats : Des méta-risques relatifs (méta-RR) significativement augmentés ont été observés pour le cancer du larynx et les expositions aux hydrocarbures aromatiques polycycliques (HAP), aux gaz d'échappement de moteurs, au travail dans l'industrie textile et dans l'industrie du caoutchouc, et pour le cancer de la cavité buccale et du pharynx et les expositions à l'amiante, aux HAP et aux gaz d'échappement de moteurs. Des augmentations de risque significatives ont été observées pour plusieurs professions et secteurs d'activité exposant notamment aux nuisances présentant des méta-RR augmentés. Les résultats des analyses par nuisance confirment l'association entre l'amiante et le cancer du larynx et suggèrent également une association avec les cancers de la cavité buccale et du pharynx. Une association avec les poussières de ciment est également suggérée. Les résultats ne sont pas en faveur d’un rôle de l’exposition aux LM et à la silice.Conclusion : Ce travail renforce l’hypothèse d’un rôle des expositions professionnelles dans la survenue des cancers des VADS. Dans l’ensemble, nos résultats suggèrent des associations entre le risque de cancer des VADS et les expositions à l'amiante, aux HAP, aux poussières de ciment, et le travail dans l'industrie du caoutchouc
Background: There is sufficient evidence that asbestos causes laryngeal cancer, but overall the role of occupational exposures in the etiology of head and neck cancer (HNC) remains largely unknown. Although several studies have reported associations between occupational exposures and HNC, it is difficult to draw firm conclusions. Objectives: (1) To summarize available epidemiologic data on occupational exposures and cancers of the oral cavity (OC), pharynx and larynx (the most frequent HNC); (2) using data from a large case-control study, to identify occupations and industries with an increased risk of HNC, then to investigate the role of some suspected occupational exposures (asbestos, mineral wools (MW), cement dust, silica). Methods: (1) A literature research and a series of meta-analyses were performed. (2) The Icare study is a French population-based case-control study including 2415 HNC cases and 3555 controls. Complete and detailed occupational histories were collected. Analyses by job title were conducted. Job exposure matrices, developed by the Occupational Health Department of the French Institute for Public Health Surveillance (InVS), were used to assess lifetime occupational exposure to asbestos, MW, cement dust and silica. Results: Significantly increased meta-relative risks (meta-RR) were obtained considering laryngeal cancer and exposures to polycyclic aromatic hydrocarbons (PAH), engine exhausts, working in the textile industry and the rubber industry, and for cancer of the OC and pharynx and exposures to asbestos, PAH and engine exhausts. Significantly increased risks were found for several jobs and industries, some of them entailing exposures to agents for which meta-RR were increased. Analyses for specific occupational exposures confirmed the association between asbestos and laryngeal cancer and showed an association with the risk of oral cavity and pharyngeal cancer. An association with exposure to cement dust was also suggested. The results did not support an association between HNC risk and exposure to MW or silica. Conclusion: This work emphasizes the role of occupational exposures in HNC. Overall, our results suggest associations between HNC and exposure to asbestos, PAH, cement dust, and work in the rubber industry

The high incidence of gastrointestinal cancers in the general population and the presence of premalignant dysplastic precursor lesions in the gastrointestinal tract make the gastrointestinal tract an ideal environment to study cancer clonality and clonal expansion. Background: Intestinal metaplastic (IM) glands in the human stomach are clonal, contain multiple stem cells and spread by fission. This mechanism of gland fission causes field cancerisation. We hypothesised that gastric adenocarcinoma (GA) progresses through a series of genetic events arising from a founder mutation. A process analogous to niche succession may also take place in the normal oesophagus. We hypothesise that oesophageal squamous cell cancer occurs by a process of field cancerisation of the oesophagus. RHBDF2 has been identified as the gene responsible for tylosis with oesophageal carcinoma (TOC). We hypothesise that RHBDF2 germline gain of function mutations might be lost during tumour progression in TOC and this might affect iRhom2 localisation in the cell. Methods and results: A cohort of 23 patients with dysplasia and a cohort of 51 GA patients were screened for genes accounting for 75% of all somatic mutations previously reported in GA. Only 13% of dysplastic patients and 31.4% of GA patients had mutations. Three dysplastic patients and six GA patients were analysed by microdissection. Small gastric cancer foci in a cohort of hereditary diffuse gastric cancer (HDGC) patients (n=5) were also screened by laser-capture microdissection (LCM) for mutations in TP53. A cohort of 30 patients was screened for common mutations in OSCC and for RHBDF2 mutations. 36.36% of the patients presented mutations. Three patients with mutations were randomly selected and areas of oesophageal squamous cell dysplasia and OSCC were analysed by LCM. Three TOC patients were also analysed by LCM and immunohistochemistry was performed for iRhom2 and ADAM17. Conclusions: The usual mutational events established for GA development during the metaplasiadysplasia- carcinoma sequence (MCS) do not fit the results from either of our two LCM mutation studies in the human stomach. Dysplasia was shown to be clonal and GA demonstrates genetic heterogeneity through clonal evolution. Field cancerisation could not be detected in HDGC using TP53 as a clonal marker. The low incidence of OSCC patients with mutations implies that other genes may be involved in the premalignant pathway leading to OSCC. Oesophageal squamous cell dysplasia and OSCC demonstrate clonal expansion through tumour progression. RHBDF2 mutations do not occur in sporadic OSCC but germline RHBDF2 mutations can be lost during tumour progression in TOC patients with LOH in 17q. Overall, the somatic mutation theory of carcinogenesis seems to hold true for both the progression to GA and OSCC, as both carcinomas seem to evolve from a single mutated stem cell and acquire genetic heterogeneity as the tumours evolve.

Thesis (MSc)--Stellenbosch University, 2004.
ENGLISH ABSTRACT: The work presented in this thesis deals with the association between cancers of the upper gastro-intestinal tract and the tumor suppressor gene, TP53, and can be divided into three parts: (i) the analysis of the mutational spectrum of TP53 with respect to laryngeal cancer, (ii) the analysis of the mutational spectrum of TP53 with respect to esophageal cancer and (iii) the analysis of TP53 transcriptional levels in esophageal cancer. Laryngeal cancer (LC) is the 6th most common cancer in the world and the 2nd most common respiratory cancer, with approximately 500 000 new cases per annum detected worldwide. Over the last few years, LC has become increasingly prevalent within the Coloured Community of the Western Cape. The mechanisms of tumorigenesis in LC remain unknown, although smoking and alcohol consumption are considered to be major risk factors. Mutations within the gene TP53 have been strongly implicated as playing a role in cancer development, as they are frequently found in several cancer types. We therefore screened exons 5 - 8 of TP53 for mutations in DNA from tumor biopsies (n=44) and blood samples (n=42) from Coloured LC patients, using polymerase chain reaction - single strand conformation polymorphism (PCR-SSCP) analysis and direct sequencing. Blood samples from a healthy, matched control group (n=40) were included in the study as controls. Significant correlations were found between the occurrence of LC and age and smoking, whereas daily meat consumption was a possible protective factor. In tumor-derived samples, mutations were found in 3 of the exons under investigation, representing 25% of the samples. The mutations were unique to the tumor biopsies, indicating a somatic origin for mutations. The data confirms that the region between codons 175 and 273 of TP53 is a mutational hotspot for cancers in general. This study reports 6 novel mutations within this same region. Esophageal cancer (EC) has a very high incidence in South Africa, relative to the rest of the world, and is particularly common amongst the Black Transkei population. The goal of this study was to determine whether there are differences in the TP53 mutational pattern observed in the Coloured Western Cape community as compared to that observed in the Black Transkei community. This required the analysis of the molecular structure of TP53, specifically exons 5 - 8, in a group of Coloured EC patients (n=44) treated at Tygerberg Hospital, Cape Town, South Africa. DNA obtained from tumor biopsies and blood (from patients) as well as from apparently healthy surrounding tissue was screened via PCR-SSCP and direct sequencing analysis. Only 4 nucleotide changes were observed from a total of 124 sequences obtained, of which two were novel to esophageal squamous cell carcinoma. These 4 nucleotide alterations were found only within the tumor biopsy sample set, representing 9% of the tumors investigated. This study revealed that the mutational spectrum of TP53 within the Coloured population of the Western Cape greatly differs from that of the Black community of the Transkei. This suggests that a different set of etiological factors are involved in the tumorigenic process for each of these distinct geographical communities, which is the subject of an epidemiological study undertaken by the MRC. The final part of this thesis deals with the quantification and comparison of TP53 transcription levels in esophageal cancer tumor tissue to the TP53 levels in healthy esophageal tissue obtained from patients from a unique geographical and ethnic background. The cohort used in this study consisted of Coloured patients (n=2) treated at Tygerberg Hospital. The LightCycler system was implemented in order to try to accurately quantify TP53 mRNA levels. Unfortunately, the desired results were unattainable due to unforeseen difficulties encountered during the study. These difficulties included the insufficient preservation of samples for RNA based studies. Several recommendations were made concerning future similar studies, including an improved planning strategy as well as the employment of an RNA stabilizing agent. Additionally, a few important contributions were made through this study, including the design and optimization of TP53 primers specifically intended for future RNA studies. These primers would enable the identification of the presence of TP53 RNA species as well as the absence of DNA contamination in a single PCR amplification step. Other contributions include the development of a well-optimized RNA extraction method for the extraction of RNA from tough tissues (such as the human esophageal tissue used in this study). This method makes the extraction of large quantities of RNA from small amounts of tough tissue types possible. In conclusion, this study has made a significant contribution to the field of cancer research, by shedding light on the TP53 mutational spectrum with regards to laryngeal as well as esophageal cancer in a population unique to the Western Cape. The first part of this thesis has been published in Cancer Genetics and Cytogenetics (Barnard, D., K. Lehmann, E.G. Haal, P.O. van Heiden, and l.C. Victor. 2003. The spectrum of mutations in TP53 in laryngeal cancer patients from a high-incidence population shows similarities to many of the known mutational hotspots. Cancer Genetics and Cytogenetics 145:126-132), of which a copy can be found in Appendix I. This work has also been presented (by D. Barnard) at an international conference entitled "Cancer of the Esophagus and Gastric Cardia: From Gene to Cure", held in Amsterdam, the Netherlands during the period 13 - 15 December 2002.
AFRIKAANSE OPSOMMING: Die werk wat in hierdie tesis voorgelê word handel oor die assosiasie tussen kankers van die boonste gastrointestinale weg en die tumor suppressor geen, TP53, en kan in 3 dele gedeel word, (i) die analise van die mutasiespektrum van TP53 in laringiale kanker (LK), (ii) die analise van die mutasiespektrum van TP53 in slukderm kanker (SK) en (iii) die analise van die transkripsievlakke van TP53 in SK. Laringeal kanker (LK) is die 6de algemeenste kanker in die wêreld en die 2de algemeenste respiratoriese kanker, met "n benaderde 500 000 nuwe gevalle jaarliks wêreldwyd. Oor die afgelope paar jare het LK "n toenemende probleem geraak, veral in die Kleurling gemeenskap van die Wes Kaap. Die meganismes van die tumorvorming in LK is onbekend, alhoewel rook-en alkoholgebruik vername risiko faktore is. Die voorkoms van mutasies in TP53 is verskeie kere aangetoon in verskillende kanker tipes en daar word vermoed dat dit "n rol speel in tumorvorming. In hierdie studie is dus na mutasies in eksons 5 - 8 van TP53 gesoek in tumor biopsie weefsel (n=44) en bloed isolate (n=42) van Kleurling LK pasiënte d.m.v. polimerase ketting reaksie - enkelstring konformasie polimorfisme (PKR-ESKP) analisering en direkte volgorde bepaling. Bloed monsters van "n vergelykbare groep (n=40) is ook in die studie ingesluit as "n kontrole. Betekenisvolle positiewe korrelasies is gevind tussen die voorkoms van LK en ouderdom sowel as rook. Daarmee saam is daaglikse vleisinname as potensiële beskermende faktor gevind. In tumor biopsies is mutasies in 3 van die ondersoekte eksons gevind, wat 25% van die biopsie monsters verteenwoordig. Hierdie mutasies is uniek aan die tumor biopsie weefsels en dui op "n somatiese oorsprong van mutasies. Hierdie bevindinge bevestig dat die gedeelte tussen kodons 173 - 273 van TP53 "n hipermuteerbare gebied geassosieer met kankers is. Hierdie studie bevestig 6 nuwe mutasies. Daar is 'n hoë insidensie van slukderm kanker (SK) in Suid Afrika relatief tot die res van die wêreld. Hierdie soort kanker word veral gevind by die Swart populasie van die Transkei. Die doel van hierdie studie was om verskille tussen die TP53 mutasie patroon van die Kleurling gemeenskap van die Wes Kaap en die Swart gemeenskap van die Transkei te vergelyk. Hiervoor is die molekulêre struktuur van TP53, veral eksons 5 - 8, in 'n groep Kleurling SK pasiënte (n=42) wat behandel is by Tygerberg Hospitaal, Kaapstad, Suid Afrika, geanaliseer. Analisering is gedoen deur DNS van tumor, bloed en ook oënskynlike gesonde aangrensende weefsel van dieselfde pasiënte te onderwerp aan PKR-ESKP analise en direkte volgorde bepaling. Slegs 4 nukleotied veranderings is gevind in 124 volgorde bepalings, waarvan 2 nuwe veranderings is in SK. Hierdie 4 nukleotied veranderinge verteenwoordig 9% van al die tumors wat ondersoek is in die studie. Hierdie studie bewys dat die mutasiespektrum van TP53 in die Kleurling gemeenskap van die Wes Kaap grootliks verskil van die Swart gemeenskap van die Transkei. Dit impliseer dat verskillende etiologiese faktore moontlik 'n rol mag speel op die tumorvormingsproses in die 2 afsonderlike geografiese gemeenskappe. Hierdie is die onderwerp van 'n epidemiologiese studie wat deur die MNR onderneem word. Die laaste deel van hierdie tesis handel oor die kwantifisering en vergelyking van TP53 transkripsievlakke in SK tumor weefsel teenoor TP53 vlakke in gesonde slukderm weefsel van pasiënte in 'n unieke geografiese en etniese agtergrond. Die studie populasie in hierdie projek het bestaan uit Kleurling pasiënte (n=2) wat by Tygerberg hospitaal behandel is. Die "LightCycler" sisteem is gebruik vir die akkurate kwantifisering van TP53 boodskapper RNS vlakke. Ongelukkig is die verlangde resultate nie gekry nie as gevolg van onvoorsiene probleme wat ondervind is tydens die studie. Hierdie probleme sluit in die onvoldoende preserv RNS studies. Hierdie inleiers maak dit nou moontlik om die teenwoordigheid van TP53 RNS spesies sowel as die afwesigheid van DNS kontaminasie in een PKR amplifikasie stap te kan identifiseer. 'n Ander belangrike bydrae is die ontwikkeling van 'n goed geoptimaliseerde RNS ekstraksie metode vir moeilike starre weelfsel tipes (soos menslike slukderm weefsel in hierdie studie) en maak die ekstraksie van groot hoeveelhede RNS uit klein hoeveelhede van moeilik hanteerbare weefsel tipes moontlik. Om saam te vat, hierdie studie het betekenisvolle bydraes gemaak tot die veld van kankernavorsing deur die ontrafeling van die TP53 mutasiespektrum in beide laringeale sowel as slukderm kanker, in 'n populasie uniek aan die Wes Kaap. Die eerste deel van hierdie tesis is gepubliseer in Cancer Geneties and Cytogenetics (Barnard, D., K. Lehmann, E. G. Hoal, P. D. van Heiden, and T. C. Victor. 2003. The spectrum of mutations in TP53 in laryngeal cancer patients from a high-incidence population shows similarites to many of the known mutational hotspots. Cancer Genetics and Cytogenetics 145: 126-132) en 'n afskrif van die artikel is ingesluit in Appendix I. Hierdie werk is ook voorgedra (deur D. Barnard) by 'n internasionale kongres getiteld "Cancer of the Esophagus and Gastric Cardia: From Gene to Cure", wat in Amsterdam, Nederland gehou is gedurende 13 - 15 Desember 2002

The incidence of neoplasia at the gastroesophageal junction has increased markedly over the past 20 years, but the mutagen responsible for this remains unknown. Human saliva contains substantial quantities of nitrite and is the main source of nitrite entering the stomach. It is derived from the enterosalivary recirculation of dietary nitrate and its reduction by buccal bacteria. Carcinogenic N-nitrosocompounds may be formed from the nitrite in swallowed saliva by bacterially-catalysed nitrosation in the achlorhydric stomach or acid-catalysed nitrosation in the healthy acid secreting stomach. Protection against luminal acid-catalysed nitrosation is provided by the ascorbic acid content of human gastric juice which reduces nitrite to nitric oxide (NO). A high luminal concentration of NO generated from salivary nitrite has been shown at the gastroesophageal junction. A bench top model has been developed to explore the chemistry occurring in an aqueous phase, representing the lumen at the gastroesophageal junction, after the addition of nitrite. Within this model an adjacent lipid phase has been created. The lipid phase represents the adjacent mucosa to the lumen or the dietary fat shown to sit within the fundus of the stomach. In this two-phase model, addition of physiological concentrations of nitrite to an acidic aqueous phase in the absence of ascorbic acid generated nitrosative stress within the aqueous phase. The addition of physiological concentrations of ascorbic acid to the aqueous phase prevents nitrosative stress within the aqueous phase but in so doing generates nitrosative stress within the lipid phase. This can be explained by the ascorbic acid converting the salivary nitrite to NO which diffuses into the lipid phase and there reacts with O2 to form the nitrosating species N2O3. The bench top model has been developed further to include the lipid antioxidants, α-tocopherol, β-carotene and BHT. All three of these antioxidants are effective in inhibiting nitrosative stress within the lipid phase. The concentration of α-tocopherol required to inhibit nitrosation is less than would be expected from the reaction equation. A possible explanation for this is that ascorbic acid recycles the active antioxidant α-tocopherol from its reduced form. Further studies to support recycling of α-tocopherol by ascorbic acid are presented within this thesis. The design of a model used in vivo to assess for nitrosative stress is discussed. The model consisted of a hydrophobic silastic tubing containing a secondary amine at a neutral pH. The hydrophobic membrane that the tubing is composed of allowed the passage of gaseous NO. Human studies in healthy volunteers were performed using the silastic tubing. The data presented shows that after a nitrate rich drink there is significantly more nitrosative stress within the upper gastrointestinal tract and this is particularly the case in the first part of the stomach where salivary nitrite meets acidic gastric juice containing ascorbic acid. Finally, the studies explore directly measuring nitrosative stress in biopsy samples from humans and rats. As nitrite has been shown previously to be a marker of nitrosative stress in bench top models biopsy samples were assessed for nitrite and nitrate concentrations. Methods for assessing nitrite and nitrate concentrations within biopsy samples from the upper gastrointestinal tract are discussed, as nitrite and nitrate have not been analysed from this region previously. Thereafter, upper gastrointestinal biopsy samples from healthy human subjects were analysed after a control drink and a drink rich in nitrate. The studies presented show that biopsy nitrate and nitrite was higher in samples taken from the proximal stomach as compared to the oesophagus and distal stomach. This suggests that there is more nitrosative stress in the biopsies from the same area as where NO is generated after a nitrate meal. Together the data presented supports a novel mechanism for N-nitrosation in the upper gastrointestinal tract of a healthy subject. The N-nitrosation is maximal where swallowed salivary nitrite from dietary nitrate meets acidic gastric juice containing the aqueous antioxidant ascorbic acid.

The aim of this study was to investigate the hypothesis that pre-therapeutic "dispositional optimism" is associated with post-therapeutic "quality of life (QOL)" in a sample of patients with upper aerodigestive tract (UADT) cancer. A sample of 101 subjects with UADT cancer was enrolled in this cohort study. QOL was evaluated through the EORTC QLQ-H&N35 and the global domain of the EORTC QLQ C-30. Dispositional optimism was measured using the Life Orientation Test (LOT). Subjects completed these self-administered questionnaires prior to treatment and one week to one month after their treatment. Other data were gathered by interview and medical chart review.
Prior to treatment, an association between dispositional optimism and QOL was observed for the global, pain, swallowing, senses and feeling ill domains. However, no such associations were observed following treatment.

This study describes, on a comparative basis, the morphology of mechanical (the linguo-laryngeal apparatus) and sensory (Herbst corpuscles and taste buds) specialisations in the upper digestive tract (bill and oropharynx) of the ostrich and emu, with a view to a better understanding of the functional significance of these structures. The ostrich and emu are commercial entities that constitute important niche industries and are farmed intensively throughout South Africa. A lack of information on the mechanical and sensory specialisations of the upper digestive tract in these two birds hampers a sound understanding of food selection and intake. A total of 48 adult (12-14 months) ostrich heads and 48 adult emu (12-14 months) heads obtained from birds at slaughter at commercial abattoirs and farms, as well as 5 ostrich chick (2-4 weeks) heads and 1 emu chick (8 weeks) head, obtained from previous research projects, were used for this study. Morphological features were described using basic gross anatomical (dissection and stereomicroscopy) and histological techniques (H&E staining), supplemented by differential staining for cartilage and bone, transmission electron microscopy and immunohistochemistry. The findings of the study were compared with the relevant literature and hypotheses for functional significance were formed. The avian glottis channels air from the oropharynx to the trachea and is situated on an elevated structure, the laryngeal mound. It is imperative that the glottis be protected and closed during swallowing, which in mammals is achieved by covering the glottis with the epiglottis, as well as by adduction of the arytenoid cartilages. An epiglottis, however, is reportedly absent in birds. Ratites such as the ostrich and emu possess a very wide glottis in comparison to other birds. The question therefore arises as to how these large birds avoid inhalation of food particles through a wide glottis, with apparently little protection, particularly as their feeding method involves throwing the food over the glottis to land in the proximal esophagus. In the ostrich, when the glottis was closed and the tongue body retracted, the smooth tongue root became highly folded and the rostral portion of the laryngeal mound was encased by the pocket in the base of the ∩-shaped tongue body. In this position the lingual papillae also hooked over the most rostral laryngeal projections. However, in the emu, retraction of the tongue body over the closed glottis resulted in the prominent, triangular tongue root sliding over the rostral portion of the laryngeal mound. In both the ostrich and emu these actions resulted in the rostral portion of the laryngeal mound and weakest point of the adducted glottis being enclosed and stabilised. Only after conducting a comparative study between these two birds using fresh specimens did it become clear how specific morphological peculiarities were perfectly specialised to assist in the closure and protection of the wide glottis. A unique anatomical mechanism in ratites was identified, described and proposed, which may functionally replace an epiglottis; the linguo-laryngeal apparatus. The oropharynx of the ostrich and emu is richly supplied with Herbst corpuscles. This widespread distribution of these mechanoreceptors has not previously been reported in birds. Specific concentrations of Herbst corpuscles within the oropharynx, which differ between the ostrich and emu, assist in the accurate positioning of the tongue and laryngeal mound for cleaning the choana (internal nares). The Herbst corpuscles are strategically located to aid in the handling and transport of food and the median palatine and ventral ridges in the ostrich display a concentration of Herbst corpuscles which denote these structures as sensory organs, namely the palatal and interramal organs. Three specific arrangements of Herbst corpuscles were noted in the oropharynx. The first arrangement consisted of groups of corpuscles located peripherally around a myelinated nerve and was present in the bill tip. The second arrangement, possibly linked to the first, was that of individual or groups of corpuscles without an obvious associated nerve and was present throughout the remaining regions of the oropharynx. The third arrangement was that of corpuscles associated with large, simple branched tubular mucus-secreting glands. The basic structure of Herbst corpuscles in the ostrich and emu, observed by light and transmission electron microscopy, of a capsule (with cellular and acellular lamella), an outer zone (collagen fibrils, fibroblasts and a fluid matrix), an inner core (formed by bilaterally symmetrical specialised Schwann cells) and a receptor axon, is similar to that noted for other avian species. However, unlike in other birds, the capsule of the Herbst corpuscle in the ostrich and emu is formed by myofibroblasts which indicates contractile properties for this component of the corpuscle in ratites. Sensory cilia were noted in the myofibroblasts of the capsule and fibroblasts of the outer zone of the ostrich Herbst corpuscle which may assist in regulating the tension of the capsule. These features have not been reported in other avian species. Although the structure of the palaeognathous palate has been widely studied, relatively little information is available on the morphology of the ratite bill. The kiwi possesses a bill tip organ and the present study confirmed the existence of this somatosensory organ in the ostrich and emu. Examination of the rhamphotheca of these two birds demonstrated numerous specialisations. In the emu, rhamphothecal serrations with intervening keratinised pegs on the rostral mandibular tomia resembled a form of pseudo-teeth. These structures may share a similar embryological origin to teeth; however, they would appear to function by channelling and enhancing vibratory stimuli to Herbst corpuscles in nearby bony pits. In the ostrich, epidermal troughs were present in the regions overlying the bill tip organ and functioned to enhance vibratory stimuli to the underlying Herbst corpuscles. Additionally, in the ostrich only, and not related to the structure or functioning of the bill tip organ, the rostral tomia and maxillary and mandibular nails were composed of typical tubular and inter-tubular horn. This may represent a unique feature in birds. The structure of the mandible and premaxilla was similar to that described previously for these birds. However, the persistence of Meckel’s cartilage through to the adult bird in the ostrich and emu is a novel avian feature not previously reported. The bony bill tips were adorned with numerous sensory (bony) pits which displayed similar distribution patterns in the ostrich and emu and indicated the presence, macroscopically, of a bill tip organ. The total number of pits in the bill tip of the ostrich and emu did not differ significantly, although regional differences did occur. The sub-divisions of the trigeminal nerve (N. opthalmicus R. medialis and N. intramandibularis) innervating the bill tip were well developed in both birds and displayed extensive branching. The emu displayed more myelinated nerve fibres in both nerves than in the ostrich. As myelinated nerve fibres supply Herbst corpuscles, the number of nerve fibres is correlated to the number of corpuscles. No correlation could be made between the number of pits in a particular region and the number of nerve fibres or with the relative percentage of Herbst corpuscles in that region. The bill tip organ in both species was basically similar except for the epidermal specialisations noted above. Two parts of the bill tip organ were recognised; the bony bill tip organ (Herbst corpuscles stacked in bony cavities and pits) and the peripheral bill tip organ (Herbst corpuscles in sheets or chains in the connective tissue between the epithelium and bone). The morphology of the bill tip organ in the ostrich and emu indicates that it is an organ that functions by direct touch. These two ratite species appear to possess the most elaborate bill tip organ of any pecking bird. The existence of a bill tip organ in the ostrich and emu is an enigma and points to the possibility that a bill tip organ is a basal structure in all palaeognathous birds (living and extinct). Furthermore, it is evident by observing the exploratory behaviour of the ostrich and emu, that they use their bill tip organ extensively as a tool for exploring and interpreting their environment as well as for discriminating food. The sense of taste in birds is an important motivator for feeding as well as initial food selection. The existence of this sense in ratites has remained largely speculative. In the present study taste buds were only identified in the emu and were predominantly located in the caudal region of the non-pigmented oropharyngeal roof and sparsely located on the oropharyngeal floor. The taste buds extended the full width of the epithelium in which they were located and were ovoid structures. The taste bud was composed of centrally located, vertically oriented light and dark cells (representing both receptor cells and supporting elements) and peripherally situated follicular cells which were continuous with the surrounding Str. germinativum of the stratified squamous epithelium. Positive IHC labelling for neurofilament demonstrated numerous fine nerve fibres (Neurofibra gustatoria) within the connective tissue immediately surrounding the taste bud. Taste bud morphology in the emu was similar to that described in other birds. However, when sectioned tangentially they were indistinguishable from the surrounding epithelium with H&E staining. By using IHC labelling, concentrations of nerve fibres could be demonstrated beneath apparently nondescript epidermal structures, thus indicating the presence of a taste bud. The distribution of taste buds in the oropharynx could be linked to the particular feeding method of the emu. Based on information from GenBank, it would appear that the relatively few taste buds present in the emu oropharynx would mainly function in distinguishing bitter taste. As bitter-tasting compounds can cause a negative association with a particular food type, it would appear that the sense of taste in the emu would predominantly function for protection and not food selection. This study revealed various unique findings regarding the mechanical and sensory specialisations in the upper digestive tract of the ostrich and emu.  The ostrich and emu possess a combination of structures which functionally replace an epiglottis, namely the linguo-laryngeal apparatus.  Herbst corpuscles are widely distributed in the oropharynx of the ostrich and emu and their distribution is related to the particular feeding habits of these birds.  The capsule of Herbst corpuscles in the ostrich and emu is composed of contractile elements, a feature not reported in other birds.  The ostrich and emu possess a well-developed bill tip organ, which is an unusual feature amongst pecking birds.  Taste buds are present in the emu and no structures resembling taste buds were identified in the ostrich.
Thesis (PhD)--University of Pretoria, 2013.
gm2014
Anatomy and Physiology
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Glucosinolates have been implicated as a mediator of the cancer-protective properties of cruciferous vegetables. Enzymatic hydrolysis of glucosinolates by plant or microbial myrosinase yields a range of metabolites including beneficial isothiocyanates. Little is known about the fate of glucosinolates after their ingestion. Using urinary end-products of metabolism as markers, measurement of the production of isothiocyanates in the digestive tract of monogastric animals has been achieved. Initially, a range of isothiocyanates were administered to rats and their excretion as mercapturic acids was quantified. Relative recovery of different isothiocyanates was found to be consistent and predictable, allowing the use of artificial isothiocyanates as recovery standards in subsequent experiments. Subsequently, the relative influence of plant and bacterial myrosinase on isothiocyanate production was quantified in rats. A proportion of 0.80 (s. e. m. 0.076) of benzyl glucosinolate was hydrolysed to isothiocyanate by plant myrosinase. In the presence of both plant and microbial activity,, the proportion of benzyl isothiocyanate release was significantly decreased (0.50 s. e. m. 0.046, p<0.01) suggesting microbial breakdown of isothiocyanates. The approach, adapted for use with human subjects showed that the proportions of allyl isothiocyanate measured after ingestion of raw and cooked cabbage were 0.37 (s. e. m. 0.045) and 0.53 (s. e. m. 0.134) respectively in healthy male volunteers. A further experiment with rats established that isothiocyanate uptake in the distal digestive tract was significantly less than in the proximal intestine (0.12 s. e. m. 0.017 and 0.48 s. e. m. 0.029 respectively), suggesting a potential underestimation of isothiocyanate release in the distal digestive tract when using urinary markers. Finally, enhancement of bacterial fermentation by addition of inulin to the diet had little influence on isothiocyanate production in the gut. The findings suggested that the formation of the cancer-protective isothiocyanates was significant, in vivo, thereby strengthening the evidence for a beneficial effect of cruciferous vegetables for health. The newly developed method opens up possibilities of concurrently exploring the digestive fate of isothiocyanates and the toxicity of carcinogenic compounds.

Même si la néphrourétérectomie totale représente le traitement de référence des tumeurs de la voie excrétrice urinaire supérieure (TVEUS), il existe un risque élevé de récidive post-opératoire qui peut survenir soit au niveau de la vessie soit dans la loge de résection et/ou sur le plan systémique. L’objectif de ce travail était de caractériser ces différents modes évolutifs. En ce qui concerne la récidive intra-vésicale, une revue systématique de la littérature avec méta-analyse a permis d’identifier les principaux facteurs de risque à la fois cliniques et anatomopathologiques. Par ailleurs, une seconde analyse de cohorte suggère que, sur le plan biologique, cet événement pourrait être en rapport avec une mutation du gène FGFR3 identifiable à partir de l’ADN urinaire. En ce qui concerne la récidive locorégionale et métastatique, une relecture centralisée de lames de TVEUS classées pT3 a permis de proposer une sous-classification pronostique sur la base de l’étendu de l’envahissement du parenchyme rénal et/ou de la graisse péripyélique (pT3a vs. pT3b) afin de mieux adapter la prise en charge post-opératoire. Cependant, l’analyse d’un registre américain a montré que l’utilisation d’une chimiothérapie adjuvante pour le traitement des tumeurs localement avancées pT3-T4 et/ou pN+ serait associée à un bénéfice en termes de survie globale pour l’ensemble de ces patients. Enfin, l’étude préliminaire d’une large cohorte nationale de cas de TVEUS a permis de valider la technique de TMA avec des coupes de 2 mm au seuil de 5% pour l’analyse pronostique de l’expression de PD-L1 sur les cellules tumorales avec l’anticorps 28.8, et de l’expression de PD-1 sur les TILs avec l’anticorps NAT105
Although radical nephroureterectomy remains currently considered as the standard of care for upper tract urothelial carcinoma (UTUC), there is a high risk of postoperative recurrence, which can occur either within the bladder or the surgical field and/or distant sites. The aim of our study was to investigate and better characterize these events. With regards to intra-vesical recurrence, a systematic review and meta-analysis was conducted to identify all significant clinical and pathological predictors. Moreover, an additional cohort study suggested that, from a biological perspective, such an event could be related to the presence of the FGFR3 mutation detected from urinary DNA. With regards to locoregional and/or distant recurrence, a central pathology review of UTUC patients with pT3 disease showed that there may be a prognostic interest in stratifying these individuals based on the extent of local invasion (pT3a vs. pT3b) to propose a risk-adapted strategy for postoperative management. Nonetheless, an US hospital-based registry study revealed that all patients with pT3-T4 and/or pN+ UTUC could derive an overall survival benefit from adjuvant chemotherapy. Finally, a preliminary analysis from a large French cohort of UTUC patients established that the 2 mm TMA technique can be used to assess the prognostic interest of determining PDL1 expression on tumor cells with 28.8 antibody and PD-1 expression on TILs with NAT105 antibody, both at the 5% threshold for positivity

Les carcinomes épidermoïdes de la tête et du cou sont souvent de mauvais pronostic, en raison de leur résistance aux traitements suivie de récidives loco-régionales, voire de métastases. Ce travail s'est focalisé sur le rôle des cellules souches cancéreuses (CSC) dans la radiorésistance d'un modèle cellulaire de cancer du larynx, SQ20B, ainsi que sur leur ciblage thérapeutique en association avec la radiothérapie photonique ou par ions carbone. Une sous-population a été isolée à partir de la lignée SQ20B par tris cellulaires successifs selon 3 critères spécifiques des CSC de tumeurs ORL : exclusion du Hoechst 33342, expression de CD44 et activité élevée de l'aldéhyde déshydrogénase (ALDH). Les cellules SQ20B/SP/CD44 high/ALDHhigh présentent bien les caractéristiques de CSC (tumorisphères, tumorigénèse, radiorésistance). La résistance des CSC aux 2 types d'irradiation, par rapport aux cellules « non souche » SQ20B/SP/CD44low/ALDHlow, implique une diminution de la mort par apoptose, une augmentation des capacités prolifératives ainsi qu'une surexpression de la voie de l'autorenouvellement Bmi1. L'effet radiosensibilisant de 3 molécules ciblant les CSC a été démontré : la mort apoptotique induite par l'UCN-01 en inhibant l'arrêt en phase G2/M ; les capacités prolifératives ciblées par l'acide trans-rétinoïque (ATRA) induisant la différenciation ; et la voie de l'autorenouvellement Bmi-1 inhibée par l'artésunate. Seule ou associées (UCN-01 + ATRA), elles agissent en synergie avec une irradiation par photons ou ions carbone. Des études pré-clinique, puis clinique, devraient confirmer l'intérêt du ciblage des CSC dans le contrôle de l'échappement de ces cancers radiorésistants
Head and neck squamous cell carcinomas (HNSCC) have a poor prognosis, due to their resistance to standard treatments. In most cases, locoregional recurrence or metastases occur. This study has focused on the role of cancer stem cells (CSC) in the radioresistance of the SQ20B HNSCC cell line and their therapeutic targeting in association with photon or carbon ions irradiation. A subpopulation of SQ20B-CSC has been isolated by cell sorting based on 3 specific characteristics of HNSCC-CSC : Hoechst 33342 exclusion, CD44 expression and high aldehyde dehydrogenase activity (ALDH). SQ20B/SP/CD44high/ALDHhigh cells show the CSC characteristics (in vitro and in vivo tumorigenesis, high radioresistance). The response of CSC to both types of irradiation was compared to the non-“stem cells” SQ20B/SP/CD44low sub-population. The observed radioresistance involves a decrease in apoptotic cell death, an increase in proliferative capacities and an overexpression of the Bmi1 self-renewing signaling pathway. The radiosensitizing effects of 3 molecules targeting the CSC has been demonstrated : an induction of apoptotic cell death by the inhibition of the G2/M phase arrest after a treatment with UCN01 ; an inhibition of proliferative capacities using the all-trans-retinoic acid (ATRA) which induce their differentiation ; and an inhibition of Bmi1 by artesunate. These treatments, alone or in combination (UCN01+ATRA) have a synergistic effect with photon or carbon ion irradiation to overcome CSC radioresistance. Preclinical and clinical studies should confirm the benefit of targeting CSC and improve the control of tumor escape in patients with radioresistant HNSCC cancers

Orientador: José Murilo Robilotta Zeitune
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas
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Resumo: A endoscopia digestiva alta (EDA) é um dos exames mais indicados para a investigação das doenças do trato digestivo alto. Normalmente, é executada em hospitais de alta complexidade e em clínicas especializadas; porém a sua grande demanda tem feito com que estes exames sejam realizados com maior frequência em centros de média complexidade. Dessa forma, este estudo teve por objetivos analisar retrospectivamente os diagnósticos de EDA realizados numa população de atendimento primário da região sudoeste do município de Campinas, São Paulo, Brasil, no período de 2000 a 2007, definindo a taxa de exames normais e a prevalência das principais doenças no tubo digestivo alto e correlacionando esses diagnósticos com faixa etária, gênero e origem de atendimento; estabelecer a prevalência do Helicobacter pylori em um segmento da população estudada, de acordo com as doenças diagnosticadas; e, finalmente, oferecer subsídios para a implantação de um modelo de atendimento primário de EDA na rede pública. Este estudo foi desenvolvido a partir dos laudos de EDA arquivados no setor especializado do referente serviço e que foram analisados de modo descritivo e estatístico. A pesquisa para H. pylori foi realizada em 2.822 (56,44%) dos pacientes, através da histologia e/ou teste da urease. A qualidade do serviço foi determinada pela ausência de complicações e pela resposta a um questionário ilustrativo aplicado a uma parcela dos pacientes. As análises estatísticas foram realizadas pelo SAS (Statistical Analysis System), o nível de significância 5% (p<0,05), utilizando-se testes Qui-quadrado e exato de Fisher, e regressão logística para os cálculos de razões de risco (Odds ratio). Na análise descritiva geral observou-se que a maioria dos exames foi realizada no gênero feminino; com idade de 40 a 49 anos, independente do gênero.As mulheres tiveram dois picos prevalentes nas faixas etárias 18-29 anos e 40-49 anos; entre os homens a prevalência foi a partir de 60 anos.A maior frequência das doenças no segmento esofágico, no total de EDAs, foi de 25,96%;entre estas, esofagites 21,32% (597 do tipo erosiva e 469 do tipo não erosiva),neoplasias esofágicasmalignas 0,30% (três do tipoprecoce e 12 do tipoavançada). No segmento gástrico,a prevalência foi 79,74%, sendo gastrites crônicas 75,82%, úlcera gástrica9,10% e neoplasias malignas gástricas 0,58% (dez do tipo precoce e 19 do tipo avançada). Já nosegmento duodenal,o índice de anormalidades foide 32,96%, sendoúlcera duodenal19,34% e duodenites 17,74%. Entre os pacientes que realizaram a pesquisa para H. pylori, notou-se prevalência significativa naqueles com úlcera duodenal (49.07%). Exames endoscópicos normais foram verificados em 604 pacientes (12,08%) com valores estatisticamente representativos na faixa etária de 18 a 29 anos e no gênero feminino. Assim, após o estudo, chegou-se à conclusão de que é viável a implantação da EDA diagnóstica no atendimento primário de saúde, com equipe bem estruturada, favorecendo a ausência de índice de complicação decorrente do procedimento, o que também foi confirmado pela avaliação favorável expressa voluntariamente por alguns pacientes
Abstract: Upper digestive tract endoscopy (UDTE) is one of the most highly indicated exams for the investigation of upper digestive tract diseases. It is normally performed in high-complexity hospitals and specialized clinics; however, the high demand for UDTE examinations and the growing number of professionals specializing in endoscopic techniques have resulted in a higher availability of these procedures at medium-complexity healthcare facilities. So, the objectives of this study were to analyze the diagnoses obtained from UDTE examinations performed in a population of primary care patients from the Southwestern region of Campinas, São Paulo, Brazil, in the period from 2000 to 2007, defining the percentage of normal examinations and the prevalence of main diseases of the upper digestive tract and correlating these diagnoses with age, gender and source of referral; to establish the prevalence of Helicobacter pylori in one segment of the studied population based on the diagnosed diseases; and to offer supporting data for the implementation of a UDTE primary care model in the public healthcare system. The design of this retrospective study was based on the UDTE reports filed with the specialized department that offers the service. Descriptive and statistical analyses were performed on these reports. The quality of the service was assessed, based on the absence of complications and on the answers given to an illustrative questionnaire applied to a portion of the patients who underwent UDTE examinations. The statistical analyses were performed with the SAS (Statistical Analysis System) software, with a significance level of 5% (p<0.05). The tests applied were Chi-square and Fisher's exact test, as well as logistic regression for the calculation of odds ratios. During the general descriptive analysis, it was observedthat the majority of examinations was conducted on female patients; and on patients ages 40-49, irrespective of gender. There were two peaks of age prevalence among women (18-29 and 40-49 y.o.); among men, the prevalent age groupwas 60 y.o. and older. Among the 5,000 analyzed UDTE examinations, the prevalence of esophageal segment disease was 25.96%, including erosive and non-erosive esophagitis(21.32%); and early and advanced esophageal cancer (0.30%). Prevalence of disease in the gastric segment was 79.74%, including chronic gastritis (75.82%), gastric ulcers (9.10%) and gastric cancer (0.58%). In the duodenal segment, the rate of abnormalities was 32.96%, including duodenal ulcers (19.34%) and duodenitis (17.74%). Out of the 5,000 examinations, a total of 2,822 patients (56.44%) were selected for H. pylori testing using the histological and/or urease methods, to investigate the correlation of this bacterium with gastric and duodenal ulcers, as well as gastritis identified as micronodular after endoscopic examination. Normal endoscopic examinations were assessed from 604 patients (12.08%), which presented statistically representative values for the 18-29 years old age group and the female gender. In conclusion, with this study, the implementation of diagnostic UDTE using a well-structured medical team is a viable option in primary healthcare. Besides, according to the favorable assessments expressed voluntarily by some patients, the procedure does not produce complications
Mestrado
Clinica Medica
Mestre em Clinica Medica

Il manque actuellement aux médecins une nouvelle méthode qui rationalise le traitement peu invasif pour en faire des procédures à opérateur unique, assistées par une caractérisation précise des tissus in situ et en temps réel, en situation de prise de décisions dans la gestion du cancer colorectal. Une solution prometteuse à ce problème a été développée par l'équipe AVR (Automatique, Vision et Robotique) du laboratoire ICube, au sein de laquelle l'endoscope interventionnel flexible (fabriqué par Karl Storz) a été entièrement robotisé, permettant ainsi à un seul opérateur de télémanipuler indépendamment l'endoscope et deux instruments thérapeutiques insérables, grâce à unité de contrôle commune. Cependant, l'endoscope flexible assisté par robot est soumis aux mêmes limites de précision diagnostique que les systèmes d'endoscopie standards. Il a été démontré que l'OCT endoscopique présente un potentiel pour l'imagerie des troubles de la voie gastro-intestinale et pour la différenciation de tissus sains des tissus malades. Actuellement, l'OCT se limite à l'imagerie de l'œsophage humain, qui présente une géométrie simple et un accès facile. Ni l'OCT, ni l'endoscope robotisé ne peuvent résoudre à eux seuls les limites de la norme actuelle de soins pour la prise en charge d’un cancer du côlon. La combinaison de ces deux technologies et le développement d'une nouvelle plate-forme pour la détection et le traitement précoce du cancer constituent l'objet principal de cette thèse, avec la vision de développer une console d'imagerie OCT et une sonde de haute technologie intégrée à l'endoscope robotisé. Ce système permet d'obtenir des images de l'intérieur du gros intestin pour la caractérisation des tissus et l'assistance au traitement, permettant ainsi à un seul opérateur d'effectuer une intervention peu invasive en mode télémanipulation
There exists an unmet clinical need to provide doctors with a new method that streamlines minimally invasive endoscopic treatment of colorectal cancer to single operator procedures assisted by in-situ and real-time accurate tissue characterization for informed treatment decisions. A promising solution to this problem has been developed at the ICube laboratory, in which the flexible interventional endoscope (Karl Storz) was completely robotized, so allowing a single operator to independently telemanipulate the endoscope and two insertable therapeutic instruments with a joint control unit. However, the robot-assisted flexible endoscope is subject to the same diagnostic accuracy limitations as standard endoscopy systems. It has been demonstrated that endoscopic optical coherence tomography (OCT) has a good potential for imaging disorders in the gastrointestinal tract and differentiating healthy tissue from diseased. Neither OCT, nor the robotized endoscope can solve the limitations of current standard of care for colon cancer management alone. Combining these two technologies and developing a new platform for early detection and treatment of cancer is the main interest of this work, with the aim of developing a state-of-the-art OCT imaging console and probe integrated with the robotized endoscope. The capabilities of this new technology for imaging of the interior of the large intestine were tested in pre-clinical experiments showing potential for improvement in margin verification during minimally invasive endoscopic treatment in the telemanipulation mode

博士
國立成功大學
臨床醫學研究所
103
Cancer is one of major health issues. Gastric cancer and esophageal squamous cell carcinoma (ESCC) are common and fatal malignancy. Despite multi-modality therapies, most patients eventually die from the disease or treatment-related complications. More comprehensive investigations of carcinogenesis and tumor progression are necessary for developing novel diagnostic and therapeutic strategies for these cancers. RUNX3 is recognized as a tumor suppressor. The tumor suppressive functions of RUNX3 were first reported in gastric epithelial cells. RUNX3 was inactivated by gene silencing or protein mislocalization in more than 80% of gastric cancers. Although restoration of RUNX3 in gastric cancer cells could inhibit tumorigenesis through regulating several target genes, the mechanisms were not clearly understood. The role of RUNX3 in regulating β-catenin and cyclin D1 in gastric cancer was studied in my thesis. RUNX3 repressed Akt1 expression through transcriptional inhibition. Two RUNX3-binding sites on Akt1 promoter were identified. The inhibition of Akt1 facilitated β-catenin degradation followed by cyclin D1 downregulation. The data suggested loss of RUNX3 in gastric cancer promoted tumorigenesis through Akt1/β-catenin/cyclin D1 signaling pathway. β-catenin and cyclin D1 are well known substrates of Pin1 which is a peptidyl-prolyl isomerase and promotes oncogenesis by regulating multiple oncogenic signaling at various levels. Pin1/β-catenin/cyclin D1 signaling pathway in ESCC was investigated. The experimental evidences were provided that Pin1 knockdown inhibited expression of β-catenin/cyclin D1 and tumorigenesis of ESCC cells. The inhibited tumorigenesis in cells with Pin1 knockdown was partially recovered by cyclin D1 restoration. In addition, high Pin1 expression was correlated with poor prognosis of ESCC patients. The results supported that Pin1 may promote ESCC aggressiveness through β-catenin and cyclin D. In summary, β-catenin and cyclin D1 are repressed by tumor suppressor RUNX3 but positively regulated by Pin1 in cancers of upper digestive tract. The results of my thesis can help people understand carcinogenic mechanisms and provide rationales for developing novel target therapy of cancer in the future.

博士
高雄醫學大學
醫學研究所博士班
104
Digestive cancer is a disease which is usually genomic or somaitc anomalies leading to uncontrollable abnormal cell growth, often invasive or diffused into other parts of the body. According to WHO, the 2015 bulletin released worldwide in cancer incidence and mortality of the main reasons for the investigation. In the next 20 years, the number of new cases will rise 70% more than the current number. Digestive cancer is among the most common forms of cancer, and two types of digestive cancer are considered to be the most deadly in Taiwan. Its association with the mechanisms of cancer development and disease progression is still a very important direction to explore. Here we try to find how the non-coding RNA molecules, gene mutation, and expression change are related to occurrence and progression of digestive cancer. There are two main topics in this thesis. The first part of the research topic is divided into two sections, i.e. (1) the esophagus chromosome analysis and utilization of the HRM method for analyzing oral cancer and colorectal cancer related gene mutations and (2) the focus on the X chromosome XIST related small RNA molecule for exploring a novel mechanism. In section one of the first part, we focused on the detection of cytogenetic alterations in esophageal cancer (EC) which demonstrated high anomalous frequency. A total of 40 cases of primary EC and their paired nearby nontumor tissues were collected. The comparative genomic hybridization (CGH) is the technique that brings out the gains and losses of chromosome fragments and was applied to determine the aberrations from the tissue DNA. In noncancer tissues, the gains were at 19p (5/40, 13%), 20q (5/40, 13%), and losses at 9p (13/40, 33%), 2q (10/40, 25%), 12q (10/40, 25%), 13q (10/40, 25%), 5q (9/40, 23%), 6q (9/40, 23%), 7q (9/40, 23%), and 8p (9/40, 23%). In the 40 cases of primary EC, the gains were at 8q (10/40, 25%), 3q (9/40, 23%), 2q (7/40, 18%), and 13q (7/40, 18%), and the losses were at 1q (8/40, 20%), 4q (8/40, 20%), 3p (7/40, 18%), 5q (7/40, 18%), and 18q (7/40, 18%) in comparison with paired nearby noncancerous tissues. We found that the loss aberrations were on 1q, 2p, 3p, 5q, 6q, 9p, 11p, 15q, 16q, 18q, 21q and gains on 20p in both tumor and nontumor tissues; nevertheless, -4p, -7q, -8p, -10q, -12q, -13q, -14q and +17p, +19q, +22q were only found in nontumor tissues and +1q, +2pq, +3q, -4q, +4q, +5q, 7p, +8q, +10q, +12q, +13q, +14q -17p, -19pq, -22q in EC. From these results, we suggest that most of the tissues near the cancer parts of EC may be considered as a precancerous region. Changes in cancer and non-cancer tissues may be caused by abnormal chromosomal changes in genes. The appearance of some of anomalous hot spots in non-cancer tissue has not been reported in medical literature so far; therefore, we believe that the alterations between cancer and non-cancer tissues may play a role in the development of EC in the Taiwanese population. In section two of the first part, we know that there are anomalous frequency regions in the chromosomes of the genes in oral squamous cell carcinoma (OSCC) in the Taiwanese population, and that TNFAIP3 acts as a negative regulator of the NF-?羠 pathway, and in lymphoma and autoimmune diseases, it is frequently inactivated by mutations and/or deletions. We investigated the prevalence of inactivation of TNFAIP3 in oral squamous cell carcinoma (OSCC). DNA was extracted from 81 cases of OSCC and 50 peripheral blood samples from normal controls. A high-resolution melting (HRM) analysis was used to characterize TNFAIP3 mutations, and the results were confirmed by direct DNA sequencing. Three mutations and three single-nucleotide polymorphisms (SNPs) were found to be associated with OSCC; the TNFAIP3 mutation occurred in 3.7% (3/81) of OSCC cases examined. p.E361K was identified as a novel mutation. A novel SNP, p.P714S differed from one reported previously (p.P714A) (rs369155845) at that site. We also identified five SNPs in 50 normal Taiwanese individuals, and two of them [c.296-15C>T (rs377482653) and c.305A>G (p.N102S) (rs146534657)] were not found in our OSCC tissue. HRM facilitated screening of genetic changes. In addition, our results indicate that the prevalence of the TNFAIP3 mutation is low in OSCC. Then, we investigated the driver gene mutations associated with colorectal cancer (CRC) in the Taiwanese population. In this study, 103 patients with CRC were evaluated. The samples consisted of 66 men and 37 women with a median age of 59 years and an age range of 26-86 years. We used high-resolution melting analysis (HRM) and direct DNA sequencing to characterize the mutations in 13 driver genes of CRC-related pathways. The HRM assays were conducted using the LightCycleⓇ 480 Instrument provided with the software LightCyclerⓇ480 Gene Scanning Software Version 1.5. We also compared the clinicopathological data of CRC patients with the driver gene mutation status. Of the 103 patients evaluated, 73.79% had mutations in one of the 13 driver genes. We discovered 18 novel mutations in APC, MLH1, MSH2, PMS2, SMAD4 and TP53 that have not been previously reported. Additionally, we found 16 de novo mutations in APC, BMPR1A, MLH1, MSH2, MSH6, MUTYH and PMS2 in cancerous tissues previously reported in the dbSNP database; however, these mutations could not be detected in peripheral blood cells. The APC mutation correlates with lymph node metastasis (34.69% vs 12.96%, P=0.009) and cancer stage (34.78% vs 14.04%, P=0.013). No association was observed between other driver gene mutations and clinicopathological features. Furthermore, having two or more driver gene mutations correlates with the degree of lymph node metastasis (42.86% vs 24.07%, P=0.043). Our findings confirm that there is a certain degree of importance regarding the 13 CRC-related pathway driver genes in the development of CRC in Taiwanese patients. The second part involves the following points : X-inactive-specific transcript (XIST), a long non-coding RNA, is essential for the initiation of X-chromosome inactivation. However, little is known about other roles of XIST in the physiological process in eukaryotic cells. In this study, the bioinformatics approaches revealed that XIST could be processed into a PIWI-interacting small RNA XPi2. The XPi2 RNA was confirmed by Northern blot assay, and its expression was gender-independent, suggesting that the role of XPi2 was beyond X-chromosome inactivation. The pull-down assay combined LC-MS-MS identified two XPi2-associated proteins, nucleolin and hnRNP A1, which were related to the formation of G-quadruplex. Moreover, the microarray data showed that the knockdown of XPi2 down-regulated the KRAS pathway. Consistently, we tested the expression of ten genes including KRAS, which were regulated by G-quadruplex formation and found that the knockdown of XPi2 caused a dramatic decrease in the transcription level of KRAS among the ten genes. The results of CD/NMR assay also supported the interaction of XPi2 and the polypurine-polypyrimidine element of KRAS. Accordingly, XPi2 may modulate the KRAS expression by attenuating G-quadruplex formation. Our present work sheds light on the novel role of Piwi-interacting RNA XPi2 in modulating the G-quadruplex formation which may play some roles in the KRAS related carcinogenesis. Based on the aforementioned results, we collected and studied 31 (62n) clinical cases of colorectal cancer and confirmed that there was correlation between XPi2 and KRAS, which led to the development of colorectal cancer, one of digestive cancers.

碩士
高雄醫學大學
公共衛生學研究所
101
Background: The medical technique is in advance in recent years, but it does not improve the survival rate of the patients with upper aerodigestive tract cancer. The main reason is the occurrence of second primary cancer. Purpose: The aim of the present study was to explore the effect of substance use and alcohol metabolizing genes on the incidence and diagnostic age of second primary cancer of upper aerodigestive tract. Furthermore, we analyzed the association between second primary cancer of upper aerodigestive tract and death. Material and methods: This was a concurrent cohort study. 399 patients with upper aerodigestive tract cancer were recruited in Kaohsiung Medical University Chung-Ho Memorial Hospital from June, 1992 to April, 2011. When the patients were diagnosed as first primary cancer of upper aerodigestive tract, we collected their blood samples, consulted their clinical medical records, and interviewed them with questionnaire. And then the patients were followed up to ascertain the occurrence of second primary cancer of upper aerodigestive tract and the occurrence of death. Results: 59 out of the 399 recruited patients suffered from second primary cancer of upper aerodigestive tract when the study ended. The incidence risk of metachronous second primary cancer in betel-quid lifetime exposure ≧800 quid-year chewers was 3.8 (95% C.I. of aHR: 1.1-13.3) times higher than in non-chewers. The incidence risk of second primary cancer of oral cavity in betel-quid starting age <20 years chewers, in betel-quid daily quantity ≧30 quid/day chewers, and in betel-quid lifetime exposure ≧800 quid-year chewers were respectively 5.4 (95% C.I. of aHR: 1.2-24.6), 4.4 (95% C.I. of aHR: 1.0-18.9), and 5.4 (95% C.I. of aHR: 1.3-22.7) times higher than in non-chewers. In addition, the early-onset risk of metachronous second primary cancer and second primary cancer of oral cavity were respectively 4.9 (95% C.I. of aHR: 1.3-19.4) and 10.5 times (95% C.I. of aHR: 1.0-111.9) higher in betel-quid starting age <20 years chewers than in non-chewers. The incidence risk of synchronous second primary cancer, second primary cancer of pharynx, and second primary cancer of esophagus were respectively 33.1 (95% C.I. of aHR: 2.0-536.2), 41.3 (95% C.I. of aHR: 1.8-927.2), 10.7 (95% C.I. of aHR: 1.1-100.9) times higher in alcohol drinkers with ADH1B G/G genotype and ALDH2 A/A+A/G genotype than in non-drinkers. Patients with second primary cancer of upper aerodigestive tract experienced a 4.5-fold (95% C.I. of aHR: 2.4-8.3) higher death risk than those who did not suffer from second primary cancer of upper aerodigestive tract. Conclusions: We found that betel-quid consumption characteristics were associated with the incidence and diagnostic age of second primary cancer of oral cavity, and that alcohol drinkers with ADH1B G/G genotype and ALDH2 A/A+A/G genotype had the higher incidence risk of second primary cancer of pharynx and esophagus. Moreover, people who were attacked by second primary cancer of upper aerodigestive tract had higher death risk than those without second primary cancer of upper aerodigestive tract.

Trabalho Final do Mestrado Integrado em Medicina apresentado à Faculdade de Medicina
Introdução: A deiscência anastomótica do trato digestivo superior é uma complicação cirúrgica severa que frequentemente acarreta elevadas taxas de mortalidade. A colocação de próteses metálicas endoscópicas tem constituído, nos últimos anos, uma alternativa à terapêutica cirúrgica, mas a sua eficácia não é ainda verdadeiramente conhecida. O presente estudo pretende avaliar a taxa de sucesso e segurança das próteses endoscópicas no encerramento das deiscências pós-cirúrgicas do trato digestivo superior, bem como os fatores preditivos de sucesso associados.Métodos: Foram analisados retrospetivamente vinte e dois doentes com deiscência ou fístula anastomótica após cirurgias do trato digestivo superior submetidos a tratamento endoscópico com colocação de prótese no Serviço de Gastrenterologia do CHUC, entre 2014 e 2019. Foi considerado sucesso terapêutico quando o encerramento completo da deiscência/fístula foi conseguido e insucesso no caso de não encerramento.Resultados: Da amostra, 59,1% eram mulheres e a idade média foi 57,1 ± 13,5 anos. A eficácia técnica deste estudo foi de 100% e a taxa de sucesso terapêutico (eficácia clínica) foi de 59,1% (13/22). A taxa de sucesso foi superior em indivíduos com menos comorbilidades (p=0,393) e com idade inferior a 61,5 anos (p=0,026), bem como em doentes com um orifício de deiscência inferior a 10 mm (p=0,143). A prótese bariátrica teve a maior taxa de sucesso de entre todas as próteses (85,7%), seguida da prótese totalmente coberta (75,0%) e da parcialmente coberta (36,4%) (p=0,113). A necessidade de colocação de 2ª prótese (58,3%) (p=0,099) e um número superior de próteses por doente (2,4 ± 0,9) (p=0,014) foram mais frequentes no grupo com insucesso terapêutico. O departamento de endoscopia esteve associado a maior taxa de sucesso (80,0%), seguido do serviço de medicina intensiva (25,0%) e do bloco operatório (0%) (p=0,07). A taxa de mortalidade global foi de 18,2% (4/22). Conclusão: O tratamento endoscópico das deiscências pós-cirúrgicas do trato digestivo superior é uma abordagem eficaz e segura, sobretudo em doentes jovens e com poucas comorbilidades. A dimensão do orifício de deiscência parece ser um fator importante para o encerramento. O diagnóstico e a colocação de prótese de forma precoce, bem como a dimensão do orifício de deiscência, aparentam ser os fatores mais importantes no sucesso da terapêutica endoscópica desta patologia.
Background: Anastomotic dehiscence of the upper digestive tract is a severe surgical complication that often leads to high mortality rates. The placement of metallic stents has been an alternative to surgical therapy in recent years, but its true efficacy is not yet known. The present study intends to evaluate the success rate and safety of metallic stents in the closure of upper digestive tract dehiscences, as well as the associated predictive success factors.Methods: We present a retrospective analysis of twenty-two patients who suffered from anastomotic dehiscence or fistula after surgery of the upper digestive tract and undergone endoscopic treatment with metallic stent placement at CHUC Gastroenterology Department between 2014 and 2019. It was considered therapeutic success when the complete closure of dehiscence / fistula was achieved and failure in case of non-closure.Results: 59.1% were women and the average age was 57.1 ± 13.5 years. The technical efficacy of this study was 100% and the therapeutic success rate (clinical efficacy) was 59.1% (13/22). The success rate was higher in individuals with less comorbidities (p=0.393) and under 61.5 years of age (p=0.026), as well as in patients with a dehiscence size of less than 10 mm (p=0.143). The bariatric stents had the highest success rate of all stents (85.7%), followed by the fully covered stents (75.0%) and the partially covered stents (36.4%) (p = 0.113). The need for placing a second stent (58.3%) (p=0.099) and a higher number of stents per patient (2.4 ± 0.9) (p=0.014) were more frequent in the group with therapeutic failure. The endoscopy department was associated with a higher success rate (80.0%), followed by the intensive care unit (25.0%) and the operating room (0%) (p=0.07). The overall mortality rate was 18.2% (4/22).Conclusion: The endoscopic treatment of post-surgical dehiscences of the upper digestive tract is an effective and safe approach, especially in younger patients with few comorbidities. The size of the dehiscence appears to be an important factor affecting its closure. Early diagnosis and placement of the stent, as well as the size of the dehiscence, appear to be the most important factors in the success of endoscopic therapy for this pathology.

碩士
國立臺灣大學
公共衛生碩士學位學程
105
Objectives 1. To validate the diagnosis of ICD codes for primary upper urinary tract urothelial invasive carcinomas (UTUC) of cancer registry database of Linkou Chang Gung Memorial Hospital 2. To analyze survival of validated primary UTUC patients and its predictive factors Methods Primary UTUC records in cancer registry database of Linkou Chang Gung Memorial from 1997 to 2011 were obtained after institutional review board approval. The medical chart of each patient was reviewed for validation for primary UTUC of ICD codes in cancer registry database. Demographic features and tumor characteristics were recorded for validated primary UTUC patients. Multivariate analyses using Cox proportional hazard model was performed for predictive factors of survival for primary UTUC patients. Results There are 1170 primary UTUC patients in cancer registry database of Linkou Chang Gung Memorial Hospital from 1997 to 2011 who have sufficient information in medical records for validation. Of the 1170 patients, 1132 patients have been validated as having primary UTUC, and the positive predictive value of this cancer registry database for primary UTUC is 96.8 %. There are 38 patients with false positive diagnoses of primary UTUC, including 16 patients of lower urinary tract urothelial carcinomas (UC), 2 patients of upper urinary tract carcinoma in situ, 2 patients of ureteral stump cancer, 3 patients of UC with unclear location, and 15 patients of urinary tract diseases other than UC. Multivariate analyses of overall survival of validated primary UTUC patients show older age group at diagnosis, male, synchronous UC in the renal pelvis and ureter, no surgery, stage grouping as regional or distant cancer are significant factors for death due to all causes. Multivariate analyses of cancer specific survival of validated primary UTUC patients show older age group at diagnosis, male, cancer diagnosed at 2004-2011, no surgery, and stage grouping as regional or distant cancer are significant predictors for death due to UC. Conclusion Cancer registry database of Linkou Chang Gung Memorial Hospital is an accurate secondary database for primary UTUC by its high positive predictive value. In order to decrease false positive diagnosis in cancer registry database for primary UTUC, other urinary tract diseases other than UC should be validated for their diagnoses and UC should be checked for whether it is primary or recurrent, located at upper or lower urinary tract and for carcinoma in situ or invasive carcinoma. For UTUC patients of females, staging grouping as localized or regional cancer, and younger age group at diagnoses, they should undergo surgery and a high probability for survival could be thereafter expected.

碩士
國立中興大學
醫學科技研究所
97
Background & Aims: Hyaluronic acid synthase type 1(HAS-1) was considered a key enzyme in the tumor proliferation and migration. We investigate the potential association between HAS-1 and clinical tumor grade, stage, chemotherapy response, tumor metastases and local recurrence. The molecular biologic cancer proliferation and migration pathway through HAS-1 was also studied. Methods: From January 2008 to March 2009, a total 32 patients who have urothelial carcinoma and received nephroureterectomy or cystectomy were enrolled. We analyzed the HAS-1 and CD44 mRNA expression of the tumor samples using the polymerase chain reaction (PCR). The clinical stage, tumor grading, angiolymphatic invasion, existence of carcinoma in situ, development of distant metastases or local recurrence were collected. We also selected urothelial carcinoma cell lines T24, TSGH, TCCSUP, RT4, 5637, J82 to investigate the correlation between cell proliferation, migration and HAS-1 expression. The possible pathway of cell proliferation through HAS-1 was studied. Results: HAS-1 mRNA PCR showed overexpression in high grade and high clinical stage tissue samples. Recurrence developed in those whose tumor tissue HAS-1 overexpression without adjuvant chemotherapy. CD44 mRNA did not showed overexpression among these tissues. In the cell line study, HAS-1 overexpression was not found. CD44 and VEGF overexpression were observed in T24 and J82 cell line and the the cell motility were also better in these two cell lines. Conclusions: HAS-1 expression combined with clinical pathological stage could offer better decision making in the adjuvant chemotherapy. Downstream CD44 and related markers need more data to support the signal transduction pathway. In cell line studies, the bladder cancer proliferation and migration pathway may correlate with the hypothetic key factor, CD44. T24 and J82 cell lines showed much more malignant behavior and were suitable for further studies.