abstract: Cell-cell interactions in a microenvironment under stress conditions play a critical role in pathogenesis and pre-malignant progression. Hypoxia is a central factor in carcinogenesis, which induces selective pressure in this process. Understanding the role of intercellular communications and cellular adaptation to hypoxia can help discover new cancer biosignatures and more effective diagnostic and therapeutic strategies. This dissertation presents a study on transcriptomic and metabolic profiling of pre-malignant progression of Barrett's esophagus. It encompasses two methodology developments and experimental findings of two related studies. To integrate phenotype and genotype measurements, a minimally invasive method was developed for selectively retrieving single adherent cells from cell cultures. Selected single cells can be harvested by a combination of mechanical force and biochemical treatment after phenotype measurements and used for end-point assays. Furthermore, a method was developed for analyzing expression levels of ten genes in individual mammalian cells with high sensitivity and reproducibility without the need of pre-amplifying cDNA. It is inexpensive and compatible with most of commercially available RT-qPCR systems, which warrants a wide applicability of the method to gene expression analysis in single cells. In the first study, the effect of intercellular interactions was investigated between normal esophageal epithelial and dysplastic Barrett's esophagus cells on gene expression levels and cellular functions. As a result, gene expression levels in dysplastic cells were found to be affected to a significantly larger extent than in the normal esophageal epithelial cells. These differentially expressed genes are enriched in cellular movement, TGFβ and EGF signaling networks. Heterotypic interactions between normal and dysplastic cells can change cellular motility and inhibit proliferation in both normal and dysplastic cells. In the second study, alterations in gene transcription levels and metabolic phenotypes between hypoxia-adapted cells and age-matched normoxic controls representing four different stages of pre-malignant progression in Barrett's esophagus were investigated. Through differential gene expression analysis and mitochondrial membrane potential measurements, evidence of clonal evolution induced by hypoxia selection pressure in metaplastic and high-grade dysplastic cells was found. These discoveries on cell-cell interactions and hypoxia adaptations provide a deeper insight into the dynamic evolutionary process in pre-malignant progression of Barrett's esophagus. / Dissertation/Thesis / Ph.D. Biological Design 2014

Este estudo propôs-se a avaliar lesões de lábio inferior de pescadores nas praias de Florianópolis, Santa Catarina, Brasil, através de análise clínica, cito e anatomopatológica. Foi realizada análise citológica de esfregaços do lábio inferior de todos os pescadores (125) cuja celularidade foi adequada (83,2% dos casos). Em 16 pescadores a avaliação clínica indicou a necessidade de biópsia, nos quais observaram-se 4 casos de lesão maligna (3,2%) e 12 de graus variados de displasia (9,6%). A análise citológica dos esfregaços não foi capaz de detectar nenhuma das alterações displásicas ou malignas diagnosticadas nas biópsias. Todos os casos em que as características clínicas indicaram a necessidade de biópsia revelaram alterações significativas na análise histopatológica. Concluiu-se que a incidência de lesões displásicas e malignas é alta na população de pescadores estudada e que está fortemente associada às manifestações clínicas correspondentes à alteração na delimitação entre vermelhão do lábio e pele e aumento da consistência à palpação, não sendo a citologia esfoliativa adequada, apenas em bases morfológicas, para avaliação de queilite actínica e câncer de lábio. / This study proposed to evaluate the injury of lower lip of fishermen on the beaches of Florianópolis, Santa Catarina, Brazil, through clinical, cytopathological and histopathological analysis. Cytological examination was performed on smears of the lower lip of all fishermen (125) whose cellularity was satisfactory in 83,2% of the cases. On 16 fishermen the clinical evaluation indicated the need of biopsy. In 4 cases (3.2%) it was observed malignant lesions and in 12 cases (9,6%) it was observed differents degrees of dysplasia. The cytological analysis was unable to detect any of the dysplastic changes or malignancies diagnosticated in the histopathological study. In all cases where the clinical features indicated the need of biopsy it had significant changes in microscopic analysis. It was concluded that the incidence of malignant and premalignant lesions is high in this fishermen studied population, which is strongly associated with the clinical manifestations corresponding to blurring of vermilion margin and infiltration, and the exfoliative cytology is inadequate, only in morphological basis, to detect dysplastic alterations and cancer of the lip.

Este estudo propôs-se a avaliar lesões de lábio inferior de pescadores nas praias de Florianópolis, Santa Catarina, Brasil, através de análise clínica, cito e anatomopatológica. Foi realizada análise citológica de esfregaços do lábio inferior de todos os pescadores (125) cuja celularidade foi adequada (83,2% dos casos). Em 16 pescadores a avaliação clínica indicou a necessidade de biópsia, nos quais observaram-se 4 casos de lesão maligna (3,2%) e 12 de graus variados de displasia (9,6%). A análise citológica dos esfregaços não foi capaz de detectar nenhuma das alterações displásicas ou malignas diagnosticadas nas biópsias. Todos os casos em que as características clínicas indicaram a necessidade de biópsia revelaram alterações significativas na análise histopatológica. Concluiu-se que a incidência de lesões displásicas e malignas é alta na população de pescadores estudada e que está fortemente associada às manifestações clínicas correspondentes à alteração na delimitação entre vermelhão do lábio e pele e aumento da consistência à palpação, não sendo a citologia esfoliativa adequada, apenas em bases morfológicas, para avaliação de queilite actínica e câncer de lábio. / This study proposed to evaluate the injury of lower lip of fishermen on the beaches of Florianópolis, Santa Catarina, Brazil, through clinical, cytopathological and histopathological analysis. Cytological examination was performed on smears of the lower lip of all fishermen (125) whose cellularity was satisfactory in 83,2% of the cases. On 16 fishermen the clinical evaluation indicated the need of biopsy. In 4 cases (3.2%) it was observed malignant lesions and in 12 cases (9,6%) it was observed differents degrees of dysplasia. The cytological analysis was unable to detect any of the dysplastic changes or malignancies diagnosticated in the histopathological study. In all cases where the clinical features indicated the need of biopsy it had significant changes in microscopic analysis. It was concluded that the incidence of malignant and premalignant lesions is high in this fishermen studied population, which is strongly associated with the clinical manifestations corresponding to blurring of vermilion margin and infiltration, and the exfoliative cytology is inadequate, only in morphological basis, to detect dysplastic alterations and cancer of the lip.

Objetivo: Determinar la frecuencia de Helicobacter pylori en muestras histopatológicas gástricas malignas y premalignas del servicio de anatomía patológica del Hospital Regional Lambayeque durante los años 2016 al 2019. Material y métodos. Estudio censal, observacional descriptivo, retrospectivo y transversal. La población de estudio estuvo conformada por los pacientes cuyas muestras histológicas gástricas fueron recibidas y estudiadas en el servicio de anatomía patológica del Hospital Regional Lambayeque. Resultados. Cumplieron con los criterios de selección 566 pacientes. La edad media fue 57,3; rango de 8 a 97 años. Hubo un predominio de pacientes entre la quinta (23.9%), sexta (24%) y séptima (17%) década de la vida. La frecuencia global de Helicobacter Pylori en las muestras seleccionadas fueron de 70.5%, con un predominio en el sexo masculino (71.2%). Los hallazgos anatomopatológicos se distribuyeron de la siguiente manera: 147 pacientes (26%) con gastritis crónica atrófica (GCA), 333 (58.8%) con metaplasia intestinal (MI), 60 (10.6%) con displasia y 26 (4.6%) con cáncer gástrico. Metaplasia intestinal fue el hallazgo más común; el mismo que se encontró en 166 personas (49.85%) con MI completa, 73 (21.92%) con MI incompleta y 94 (28.22%) con MI mixta. Conclusiones La frecuencia de Helicobacter Pylori (HP) fue alta en las lesiones premalignas, mientras que no hubo diferencias en la presencia o ausencia en muestras gástricas malignas. Conforme avanzaba la edad disminuía la frecuencia del HP pero aumentaban la gravedad de las lesiones. / Objective: Determine the frequency of Helicobacter pylori in malignant and premalignant gastric histopathological samples from the pathological anatomy service of the Hospital Regional Lambayeque during the years 2016 to 2019. Material and methods. Census, observational, descriptive, retrospective and cross-sectional study. The study population was made up of patients whose gastric histological samples were received and studied in the pathological anatomy service of the Hospital Regional Lambayeque. Results. 566 patients fulfilled the selection criteria. The mean age was 57.3; range from 8 to 97 years. There was a predominance of patients between the fifth (23.9%), sixth (24%) and seventh (17%) decades of life. The overall frequency of Helicobacter Pylori in the selected samples was 70.5%, with a predominance in the male sex (71.2%). The anatomopathological findings were distributed as follows: 147 patients (26%) with chronic atrophic gastritis (CAG), 333 (58.8%) with intestinal metaplasia (IM), 60 (10.6%) with dysplasia and 26 (4.6%) with gastric cancer. Intestinal metaplasia was the most common finding; the same that was found in 166 people (49.85%) with complete MI, 73 (21.92%) with incomplete MI and 94 (28.22%) with mixed MI. Conclusions The frequency of Helicobacter Pylori (HP) was high in premalignant lesions, while there were no differences in the presence or absence in malignant gastric samples. As age advanced, the frequency of PH decreased but the severity of the lesions increased.

La morbi-mortalité élevée des carcinomes épidermoïdes de la cavité orale (CECO), qui peuvent se développer à partir de lésions orales à potentiel malin (LOPM), rend indispensable le développement de nouvelles stratégies thérapeutiques. Le décryptage de l’hétérogénéité moléculaire aux différentes étapes de la carcinogénèse orale pourrait permettre de personnaliser les stratégies thérapeutiques de prévention et de traitement de ces cancers. Notre objectif était de caractériser l’hétérogénéité transcriptomique des LOPM et des CECO.Nous avons d’abord défini des signatures transcriptomiques associées aux changements histologiques de la carcinogénèse orale observés dans le modèle murin induit par le 4-NQO, montrant la pertinence de l’analyse de la dynamique temporelle du transcriptome pour améliorer la prévention des CECO. Cependant, ce modèle ne représentant qu’un sous-groupe particulier des CECO, nous avons ensuite étudié l’hétérogénéité inter-lésionnelle des LOPM en identifiant deux sous-types transcriptomiques principaux nommés « classical » et « immunological », qui sont caractérisés par différents biomarqueurs de risque de CECO.Au stade invasif, nous avons également étudié l’hétérogénéité transcriptomique des CECO HPV-négatifs entre les patients non-fumeurs non-buveurs (NFNB) et les patients fumeurs buveurs (FB). Le microenvironnement immunitaire était la principale différence biologique entre NFNB et FB, suggérant un bénéfice accru des immunothérapies chez les NFNB. Le profil transcriptomique de réponse antivirale observé dans les CECO des NFNB pourrait être en faveur de leur origine virale. En conclusion, l’hétérogénéité transcriptomique des LOPM et CECO suggère de personnaliser les stratégies thérapeutiques des patients porteurs de ces lésions / Oral squamous cell carcinomas (OSCC), which may develop from oral premalignant lesions (OPL), are associated with a substantial morbidity and mortality. A better understanding of the molecular heterogeneity at different steps of oral carcinogenesis may help to refine prevention and treatment strategies of patients suffering from OPL and OSCC. Our goal was to decipher transcriptomic hetereogeneity of OPL as well as OSCC. Using the 4-NQO murine model of oral carcinogenesis, we first identified transcriptomic signatures that characterized the dynamics of gene expression changes through different stages of disease progression, and that could be relevant for refining prevention strategies. Because this model represents only a subgroup of patients suffering from OSCC, we then investigated inter-OPL molecular heterogeneity. We identified two distinct gene expression subtypes, which were named classical and immunological and were characterized by different biomarkers of cancer risk. At invasive steps, we investigated transcriptomic heterogeneity between HPV-negative OSCC from never-smoker never-drinker (NSND) and smoker drinker (SD) patients. The immune microenvironment was the main biological difference between OSCC from NSND and SD, suggesting higher clinical benefit of immunotherapies in OSCC from NSND. The antiviral gene expression profile of OSCC from NSND could suggest a viral origin.In conclusion, we investigated transcriptomic heterogeneity of OPL as well as OSCC, that could help to refine their prevention and treatment strategies