Orientador: Ana Sueli Rodrigues Cavalcante / Banca: Adriana Aigotti H. Brandão / Banca: Ana Lia Anbinder / Banca: Marília T. Martins / Banca: Fábio L. Forti / Resumo: A queilite actínica (QA) é uma lesão multifocal que acomete o vermelhão do lábio com potencial de malignização para carcinoma epidermóide (CE). O receptor para o fator de crescimento epidermal (EGFR) é membro da família dos receptores tirosina quinase que participa da transformação e progressão da neoplasia maligna. O objetivo desta pesquisa foi verificar a expressão de HER-1 e HER-2 totais e fosforilados e possíveis correlações das expressões destas proteínas com lesões de QA e CE de lábio inferior por imunoistoquímica. Foram um estudo de 50 casos de QA, 50 casos de CE e 14 de Controle. Expressão das proteínas foi baseado num escore. Os dados obtidos foram analisados pelo teste de Kruskal-Wallis e como análise post-hoc o teste de Mann-Whitney com correção de Bonferroni e, correlação de Spearman. O nível de significância escolhido foi o valor convencional de 5%. A análise da comparação foi estatisticamente significativa na membrana do pHER-2, grupos Controle x QA e QA x CE; no citoplasma do HER-1, grupos Controle x QA, do pHER-1, grupos Controle x QA e Controle x CE, do pHER- 2, grupos Controle x QA e Controle x CE; no núcleo do pHER-1, grupos Controle x QA, do HER-2, Controle x QA e Controle x CE (p<0,05). O estudo da correlação foi estatisticamente significativa na membrana do HER-1 x pHER-2 no grupo QA, HER-1 x HER-2, HER-1 x pHER-1, HER-2 x pHER-1 no grupo CE; no citoplasma entre HER-1 x HER-2 no grupo QA, HER-1 x HER-2 no grupo CE; no núcleo entre HER-2 x pHER-1 no grupo Controle (p<0,05). Estes dados sugerem que a maior marcação no grupo Controle poderia ser decorrente da variedade de lesões benignas que compõem esse grupo e que poderiam apresentar proliferação aumentada. Localização nuclear poderia estar relacionada não apenas como iniciadores das cascatas intracelulares, mas também como fatores de transcrição... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Actinic cheilitis (AC) is a multifocal lesion that occurs in lip vermillion with potential of malignant transformation to epidermoid carcinoma (EC). Epidermal growth factor receptor (EGFR) is a member of tyrosine kinase family, involved in transformation and progression of malignant tumour. The aim of this study was to analyse the expression of total and phosphorylated HER-1 and HER-2 and correlate expression of these proteins with lesions of AC and CE in lower lip by immunohistochemistry. It was a study of 50 cases of AC, 50 of EC and 14 of Control. Proteins expressions were based on a score. Obtained datas were analysed by Kruskal-Wallis test and post-hoc analysis with Mann-Whitney test with Bonferroni correction and, Spearman correlation. The level of significance was 5%. The analysis of the comparison was statistically significant in membrane of pHER-2, group Control x AC and AC x EC; in cytoplasma of HER-1, Control x AC, pHER-1,Control x AC and Control x EC, pHER-2, Control x AC and Control x EC; in nucleus of pHER-1, Control x AC, HER-2, Control x AC and Control x EC (p<0,05). The study of the correlation was statistically significant in membrane of HER-1 x pHER-2 expression in AC, HER-1 x HER-2, HER-1 x pHER-1and HER-2 x pHER-1 in EC; in cytoplasma, HER-1 x HER-2 in AC, HER-1 x HER-2 in EC; in nucleus, HER-2 x pHER-1 in Control (p<0,05). Our findings suggested that a higher expression in Control group could be due to a composition of this group by a variety of benign lesions that could present increased proliferation. Nuclear localization could be related not only with the action of intracellular cascade beginners, but also to action as transcription factors. Phosphorylation of HER-1 and HER-2 by MAPK pathway can be independent of total level of proteins in AC and EC lip lesions, because phosphorylation might be increased indirectly by UV radiation in a ligand independent way... (Complete abstract click electronic access below) / Doutor

Squamous cell carcinoma (SCC) is the most common histological type of cancer in the head and neck region and arises in the epithelial mucosa of the upper aerodigestive tract. Approximately one and a half million people are living with the diagnosis. Despite efforts in prevention and advances in treatment, the 5-year survival rate still lies around 60%, and recurrences and second primary tumors remain a problem. Moreover, treatment responses vary from patient to patient, highlighting the need for individually tailored treatments. To make this possible, biomarkers predicting treatment outcome are needed to better guide treatment decisions. The aim of this thesis was to evaluate the expression of certain proteins and the frequency of certain SNPs (Single nucleotide polymorphisms) in tumor biopsies and cell cultures of head and neck squamous cell carcinomas (HNSCC), and to explore their potential as biomarkers for treatment outcome. Furthermore, we aimed to study the impact of hypoxia on treatment response, epithelial-tomesenchymal transition (EMT), and induction of cancer stem cells (CSC). In papers I and II, we investigated two proteins, survivin and WRAP53β, using immunohistochemistry (IHC) in tumor biopsies from 40 patients categorized as Non-responders or Responders to radiotherapy. High expression of survivin and nuclear expression of WRAP53β were significantly more prevalent in the Responder group. The combination of these two factors correlated strongest to overall survival, but not to a significantly higher extent compared to survivin alone. Moreover, when examined separately, a high percentage of p53-stained cells and the presence of the SNP FGFR4 Gln388Arg correlated to improved overall survival, whereas the SNP XPD Lys751Gln was associated with worse overall survival. The latter three showed no significant correlations to radiotherapy response. In paper III, the two most promising proteins identified in papers I and II were analyzed in a study cohort of 149 tumor biopsies of glottic laryngeal SCC, categorized as T2N0-T3N0. In this patient group, no significant associations between survivin expression and survival could be found. However, expression of cytoplasmic WRAP53β was significantly linked to worse disease-free-survival (DSF) compared to nuclear WRAP53β or negative staining for WRAP53β. Positive expression of p16INK4a was found in 7% of the tumors. The prevalence of p16 INK4a was higher in younger patients (&lt;60) and associated with absence of recurrence and longer DSF. In paper IV, five HNSCC cell lines were cultured in normoxic (20% O2) and hypoxic (1% O2) conditions and changes in treatment response, EMT profile, and expression of CSC markers were examined. As expected, hypoxia induced EMT and to a certain extent expression of CSC markers. Silencing of the hypoxia-inducible-factor-1α (HIF-1α) only partly reversed these effects, suggesting that other mechanisms are involved. Whereas most cell lines became more resistant to treatment in hypoxia, one cell line (LK0412) became more sensitive to cetuximab-treatment in hypoxia, an effect that was revoked by depletion of HIF-1α, suggesting a possible sensitizing effect of HIF-1α to cetuximab-treatment. Taken together, WRAP53β appears to be a promising biomarker candidate for treatment outcome in HNSCC, but further evaluation especially on the subcellular localization of WRAP53β is required. Even though the role of survivin in radiotherapy response in glottic SCC seems to be insignificant, it might have a more important role in other HNSCC subsites. As far as the effects of hypoxia, it appears that hypoxia might have a sensitizing effect on cetuximab-treatment in certain cases, which seems to be HIF1-α –dependent. Further studies are required to clarify the importance of this observation.

Lysosomes, the recycling units of the cell, participate in the signaling pathway to apoptosis, which has stimulated the search for anti-cancer drugs targeting the lysosomal compartment. Lysosomes are, however, often altered in cancer cells. The aim of this thesis was to investigate the involvement of lysosomes during apoptosis in normal and cancer cells. We developed and used flow cytometric methods to measure cytosolic and lysosomal pH in cells. The cytosolic pH of U937 cells decreased, in a caspase-independent way, by 1.4 pH-units during apoptosis. Concomitantly, the lysosomal pH increased from 4.3 to 5.2, suggesting that proton release from lysosomes might be responsible for cytosolic acidification. When studying the lysosomal pH of head and neck squamous cell carcinoma (HNSCC) cell lines and normal oral keratinocytes (NOKs), the pH was significantly increased in three of five HNSCC cell lines, as compared to NOKs. Moreover, high lysosomal pH correlated to low expression of the B subunit of the vacuolar V0/V1-ATPase, a necessary component of the proton pump responsible for lysosomal acidification, and to reduced intrinsic cisplatin sensitivity. Cisplatin-induced apoptosis was, at least partly, dependent on lysosomal cathepsins. When investigating the colony formation ability of the two HNSCC cell lines LK0412 and SqCC/Y1, both were found to give rise to holoclones, indicating the presence of cells with cancer stem cell properties. Holoclone cells from the LK0412 cell line were less sensitive to cisplatin compared to more differentiated paraclone cells. Moreover, we detected differences in intracellular localization of the lysosomal compartment and expression of cathepsins between holo- and paraclone cells. This thesis shows that changes found in the lysosomal compartment of cancer cells, such as alteration of lysosomal pH, might influence the outcome of a drug treatment. In addition, differences in drug sensitivity between subpopulations of tumor cells may affect the outcome of an anticancer therapy. / Programmerad celldöd eller apoptos är en viktig mekanism för att upprätthålla balans mellan kroppens celler. Vid exempelvis cancer fungerar inte styrningen av denna process, vilket leder till att för få celler dör och en tumör kan växa ohämmat. Denna avhandling fokuserar på lysosomen, en mycket sur organell i cellen som är ansvarig för nedbrytning av cellmaterial. Hos cancerceller är lysosomerna ofta förändrade. Vi har undersökt lysosomernas roll under apoptos hos normala celler och hos cancerceller. För att kunna undersöka pH-förändringar under apoptos har vi utvecklat metoder att mäta cytosoliskt och lysosomalt pH med hjälp av en teknik som kallas flödescytometri. I apoptotiska celler ser vi att det cytosoliska pH:t sjunker med 1.4 pH-enheter till pH 5.7 samtidigt som det lysosomala pH:t ökar från 4.3 till 5.5. Detta tyder på att läckage av vätejoner från lysosomerna kan orsaka en försurning av cytosolen under apoptos. Genom att studera normala orala keratinocyter och jämföra dessa mot fem olika cellinjer eeablerade från skivepitelcancer från munhåla har vi också funnit ett samband mellan det lysosomala pH:t och känsligheten för cellgiftet cisplatin. Cisplatinbehandling leder till apoptos hos alla celler men en högre dos krävs hos celler som har ett högt lysosomalt pH. Tumörer tros innehålla ett litet antal sk cancerstamceller, som har förmåga att kontinuerligt kopiera sig själva utan att åldras. Överlevnad av dessa celler tros vara orsaken till att en tumör återkommer efter en behandling. Vi visar i denna avhandling att cellinjer från skivepitelcancer innehåller celler som har cancerstamcellsegenskaper, och att dessa celler kan ha en lägre känslighet mot cisplatin jämfört med mer utvecklade cancerceller. Lysosomerna utgör ett intressant framtida mål för nya cancerläkemedel. I denna avhandling visar vi att förändringar i det lysosomala systemet kan påverka effekten av ett läkemedel och att skillnader mellan olika sub-populationer av celler från samma tumör kan påverka resultatet av en behandling.

The search for the cure for cancer is currently a multi-billion dollar industry and the search for the elusive “magic bullet”, i.e. the perfect cancer drug that would interact therapeutically with cancerous tissues while having a minimal effect on healthy cells, is the topic of many research studies in the world today. A large number of novel drugs or drug complexes and conjugates are being synthesized and subjected to rigorous evaluation in the race to find the perfect cure. ECDG (Ethylene diCysteine DeoxyGlucose) seems to have promising cancer targeting ability. Even though this compound has been described in a few publications, we could not find any reference to the current use of ECDG in oncology clinics, either as a therapeutic agent, or as a diagnostic tool for imaging purposes. It was also not possible to purchase pure ECDG anywhere in the world. This prompted us to further investigate ECDG as a possible candidate for cancer targeting research, either as an imaging agent for cancer diagnosis or complexed with an anti-cancer agent for therapeutic purposes. Detailed investigations done in our laboratory can be divided into the following categories: - Development of a synthetic method for ECDG on a multigram scale ; - Purification of prepared ECDG not using the described dialysis method that only allows the purification of small quantities of ECDG (mg scale) ; Detailed investigation of the chemistry involved in the preparation of pure ECDG and its metal complexes ; - Investigation of the stability of ECDG and its metal complexes that is essential data required for any pharmaceutical agent ; - Preparation of ECDG complexes for use as a diagnostic tool, i.e. complexation with 99mTc ; Investigation of the bio distribution of ECDG-ReO complexes ; - Preparation of an ECDG kit as a diagnostic tool for use in oncology clinics. The development of novel aromatic ligands having similar characteristics compared to ECDG, containing an N2S2 chromophore as donor atoms, to further investigate their targeting capabilities, have also been investigated. All intermediates and final compounds were characterized mainly by ESI MS, in some cases IR and NMR whenever available. Successful preparation and purification of ECDG ands its metal complexes was achieved and extensively characterized and evaluated. Efforts directed towards the development of ECDG at NECSA, South Africa, were also rewarded with significant success. Furthermore, significant development regarding the synthesis of two novel compounds with ECDG-like characteristics was also completed.

Le cancer colorectal est un des cancers les plus fréquents en France. Les patients présentant une inflammation chronique de l'intestin sont à haut risque de développer un cancer colorectal. Il a récemment été démontré que certaines bactéries de l'espèce Escherichia coli pouvaient être impliquées dans la genèse de maladies inflammatoires intestinales, par des mécanismes d'adhésion et d'invasion aux cellules épithéliales intestinales faisant intervenir le récepteur CEACAM6, marqueur tumoral reconnu dans le cancer colorectal. Nous avons montré que certaines bactéries de l'espèce E. coli colonisaient la muqueuse colique de patients atteints de cancer colorectal et possédaient des propriétésd'adhésion et d'invasion dans les cellules épithéliales intestinales. Ces souches synthétisent des cyclomodulines variées susceptibles de jouer un rôle dans la carcinogenèse colique, et colonisent davantage les tumeurs les plus évoluées. Une corrélation a été observée entre la colonisation de la muqueuse colique par un clone unique de ces E. coli et l'expression du récepteur CEACAM6. Nous avons montré in vitro que certains clones de pouvaient induire l'expression de CEACAM6 par des cellules épithéliales intestinales en culture. Enfin, sur modèle animal transgénique exprimant le récepteur humain CEACAM6, ces mêmes clones ont montré des capacités de colonisation très supérieures à desE. coli non pathogènes, et l'induction d'une surexpression de marqueurs de prolifération au niveau de la muqueuse colique. Les E. coli associés à la muqueuse colique pourraient ainsi participer à la promotion du cancer colorectal via l'induction d'une surexpression du récepteur CEACAM6 et d'une hyperprolifération des cellules épithéliales. / No abstract available

No description available.

Tumors are mutated abnormal groups of cells that develop at any stage of life in any part of the body. Mammilla tumors appear in chest tissue that contain malignant cells in the terminal ductal-lobular unit, where the risk of the development of a mammilla tumor increases with age with a probability of 14.7%. Previous reviews have only focused on radiotherapy and digital mammography, while this review is, to the best of the author´s knowledge, the first review that encompasses the tomosynthesis and presumptive magnetic resonance using digital mammography. The aim of the meta-analysis was to determine the extent in which mass-testing of mammilla tumor metastasis can lead to its mitigation in adult females of all age-groups. The research question was the following: To what extent can mammilla tumor metastasis be mitigated by mass-testing of adult females of all age-groups? As part of the meta-analysis, a literature review was conducted using a selection of keywords in search queries on Pubmed, Libsearch and Academic Search Elite. In conclusion, mass-testing of mammilla tumor metastasis does not lead to a mitigation in adult females of all age-groups, since there was not a statistical significance of pooled value as indicated by the forest plot and the funnel plot indicated that the publication bias had some effect and the Mann-Whitney U-test also indicated that there was not a significance difference. Future research may consist of whether adult females within the age-range of 60-80 benefit from the test.

<p>2022-03-22</p>

<p>2022-03-21</p>

No description available.