Η ακεραιότητα και η λειτουργία της μιτωτικής συσκευής διαδραματίζει ουσιώδη ρόλο για τον ορθό προσανατολισμό και την ολίσθηση των χρωμοσωμάτων στους πόλους της ατράκτου, οδηγώντας στον ισομερή διαχωρισμό των χρωμοσωμάτων κατά τη μιτωτική ή μειωτική διαίρεση. Τροποποιήσεις του δικτύου των μικροσωληνίσκων (α- και β-τουμπουλίνη) και των κέντρων οργάνωσης αυτών (ΜΤΟC, γ-τουμπουλίνη) είναι δυνατόν να προκαλέσουν βλάβες στη μιτωτική συσκευή, διαταράσσοντας το χρωμοσωματικό αποχωρισμό, με αποτέλεσμα το σχηματισμό ανευπλοειδικών κυττάρων. Η διουρητική φαρμακευτική ένωση υδροχλωροθειαζίδιο (HCTZ) χορηγείται κατά της υπέρτασης και είναι γνωστό ότι προκαλεί μη αποχωρισμό σε διπλοειδή στελέχη του μύκητα Aspergillus nidulans. Πρόσφατες μελέτες της ερευνητικής μας ομάδας έχουν δείξει ότι επάγει αυξημένες συχνότητες μικροπυρήνων και διαταράσσει το χρωμοσωματικό αποχωρισμό σε καλλιέργειες ανθρωπίνων λεμφοκυττάρων in vitro. Στην παρούσα εργασία μελετήθηκε η επίδραση του HCTZ στην οργάνωση του δικτύου των μικροσωληνίσκων κατά τη μεσόφαση και τη μίτωση, με συνδυασμένη εφαρμογή μεθόδων διπλής ανοσοσήμανσης των πρωτεϊνών των μικροσωληνίσκων, του κεντροσώματος και του κινητοχώρου. Εφαρμόστηκε επίσης in situ υβριδοποίηση με φθοροχρώματα (FISH), με α-satellite πανκεντρομερικό ανιχνευτή, για τον εντοπισμό μη ενσωματωμένου (lagging) χρωμοσωματικού υλικού. Η μελέτη πραγματοποιήθηκε σε κυτταρικές σειρές μυός C2C12 και ανθρώπου HFFF2. Παρατηρήθηκε ότι το HCTZ προκαλεί μείωση του ρυθμού διαίρεσης, αποδιοργάνωση του δικτύου των μικροσωληνίσκων και αυξημένη συχνότητα ανώμαλων μεταφάσεων με ποικίλο αριθμό σημάτων γ-τουμπουλίνης. Αυξάνει το ποσοστό των μεταφάσεων και μειώνει το ποσοστό των ανα-τελοφάσεων, προκαλώντας συσσώρευση των κυττάρων στο στάδιο της μετάφασης. Επίσης, επάγει τη χρωμοσωματική καθυστέρηση, καθώς αυξάνει τη συχνότητα των μικροπυρήνων που παρουσιάζουν τόσο σήμα κινητοχώρου όσο και σήμα κεντρομέρους. Η γενετική δράση του στα κύτταρα C2C12 δε φαίνεται να επηρεάζεται σημαντικά από τη χρονική διάρκεια έκθεσης των κυττάρων σ’ αυτό. Από τις δυο κυτταρικές σειρές που χρησιμοποιήθηκαν φαίνεται ότι τα κύτταρα C2C12 είναι περισσότερο ευαίσθητα στην απόκριση στο HCTZ. Τα αποτελέσματα μας, υποδεικνύουν ανευπλοειδογόνο δράση της φαρμακευτικής ένωσης, επιβεβαιώνοντας και ενισχύοντας προηγούμενα ευρήματα της ερευνητικής μας ομάδας. / The integrity and function of mitotic apparatus play essential role for the equitable orientation and the slipping of chromosomes to the spindle poles, indicating normal distribution of chromosomes during mitotic or meiotic division. Modifications of the microtubule network (α- and β- tubulin) and microtubule-organizing centers (MTOC, γ- tubulin) may cause severe damage to the mitotic apparatus, disturbing the segregation of chromosomes and resulting to aneuploid cells. The diuretic drug hydrochlorothiazide (HCTZ) is used for the treatment of hypertension and has been found to induce non-disjunction in diploid strains of Aspergillus nidulans. Recent studies of our team have shown that HCTZ produces increased frequencies of micronuclei and disturbs chromosome segregation in human lymphocytes cultures treated in vitro. In the present study was investigated the effect of HCTZ on the organization of the microtubule network during mesophase and mitosis, with combined application of double immunofluorescence staining assay, for the visualization of microtubules, centrosomes and kinetochore proteins. Fluorescence in situ hybridization (FISH), with α-satellite pancentromeric probe, was also applied, for the localization of not integrated (lagging) nuclear material. The study was realized in C2C12 mouse cells and HFFF2 human cells. Our results revealed that HCTZ causes decrease of the cell division rate, disorganization of the microtubule network and increased frequency of abnormal metaphases with various γ-tubulin signals. HCTZ increases the percentage of metaphases and decreases the percentage of ana-telophases, indicating a metaphase arrest. Also, induces chromosome delay, as was shown from the high frequency of micronuclei that presents kinetochore and centromere signal. The genetic activity of HCTZ in C2C12 cells does not appear to be significantly influenced by the duration of the cell’s exposure time to the drug. It appears that C2C12 mouse cells are more sensitive in their response to the HCTZ. These results indicate aneugenic activity of this drug, confirming and enhancing our previous findings.

Orientador: Marcio Ajudarte Lopes / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-17T15:24:01Z (GMT). No. of bitstreams: 1 Gouvea_AdrieleFerreira_D.pdf: 1529519 bytes, checksum: 67d58c675522b5dd769d5fcad163d152 (MD5) Previous issue date: 2011 / Resumo: Leucoplasia verrucosa proliferativa (LVP) tem como principais características acometer principalmente mulheres, com idades acima dos 60 anos, sem hábitos nocivos, com lesões multifocais, recorrentes após excisão e com altas taxas de malignização. Alguns estudos com proteínas que podem estar envolvidas no controle do ciclo celular, incluindo Mcm2 e geminina, e análise de ploidia do DNA têm sido realizados com o objetivo de identificar lesões com maior predisposição para transformação maligna. Objetivos: Determinar a correlação das características clinicopatológicas de 21 pacientes com diagnóstico de LVP a seu estado de ploidia do DNA e expressão de Ki-67, Mcm2 e geminina. Métodos: 65 amostras de biópsia de 21 pacientes com LVP e 12 amostras de mucosa oral normal foram coletados, feitas imunoistoquímicas para ki-67, Mcm2 e geminina e realizada a análise da ploidia do DNA utilizando citometria de imagem (ACIS III); Resultados: Relação mulher: homem foi de 6:1 e a média de idade foi 65,5 anos. Dos 21 casos, 17 (80,96%) não reportaram fumo ou consumo de bebidas alcoólicas. Transformação maligna foi observada em nove pacientes (42,86%), em um tempo de seguimento clínico de 7,38 anos. Dos 21 pacientes, vinte tiveram seu DNA analisado por citometria de imagem e aneuploidia foi encontrada em 95,24% dos casos. A freqüência e severidade da aneuploidia e valores médios do índice de heterogeneidade (HI) aumentaram de acordo com o aumento das anormalidades epiteliais (p<0.0001), assim como as frações excedentes de 5n (p=0.0007). Os casos que desenvolveram carcinoma não apresentaram status aneuplóide mais grave do que as outras amostras (a maioria foi moderadamente aneuplóide). Em cinco casos as biópsias iniciais apresentando hiperqueratose e acantose ou displasia leve mostraram status aneuplóides e progrediram para carcinoma (55,5%). Não houve correlação entre os graus de displasia e a expressão de das diferentes proteínas estudadas, exceto para Mcm2 (p= 0.0317). Conclusões: Estes achados associados aos altos índices de anormalidades na ploidia do DNA podem contribuir para previsão de áreas com chances de malignização e suportam a afirmação de que LVP é uma entidade de fato distinta. / Abstract: Proliferative verrucous leukoplakia (PVL) presents as main characteristics: affects mostly women, with ages over 60 years, not presenting harmful habits; presence of multifocal lesions, recurrent after excision, with high malignization rates. Some studies with proteins that may be involved in the cell cycle control, including Mcm2 and geminin, and DNA ploidy analyzis has been performed aiming to identify lesions with a greater predisposition to malignant transformation. Objectives: To determine the correlation of the clinicopathological features of 21 PVL patients with their DNA ploidy status and Mcm2, geminin and Ki-67 expression. Methods: 65 biopsy specimens of 21 PVL patients and 12 normal oral mucosa were collected; immunohistochemistry to Mcm2, geminin and ki-67 and DNA ploidy analysis using image based citometry (ACIS III) were performed. Results: Female: male ratio was of 6:1 and the average age was 65.5 years. Of the 21 PVL cases, seventeen (80.96%) did not report smoking or alcoholic habit. Malignant transformation was observed in nine patients (42.86%). Of the 21 patients, twenty had the DNA examined by an image-based cytometry and aneuploidy was found in 95.24% of the cases. The frequency and severity of aneuploidy and the mean values of DNA HI increased according to the epithelial abnormality (p<0.0001), as well the 5n exceeding fractions (p=0.0007). Cases that developed carcinoma did not presented higher ploidy status compared to the other samples (the majority was moderately aneuploidy). In five cases (55.5%), initial biopsies presenting hyperkeratosis and acanthosis or mild dysplasia showed aneuploid status and latter developed carcinoma. There was no correlation between the grades of dysplasia and the LI of different immunohistochemically studied proteins, except for Mcm2 (p= 0.0317). Conclusions: This finding associated to the high incidences of DNA ploidy abnormalities may contribute to predict areas prone to malignant transformation and to support the hypothesis that PVL is a distinct entity. / Doutorado / Patologia / Doutor em Estomatopatologia

Submitted by Cássia Santos (cassia.bcufg@gmail.com) on 2015-10-28T13:15:45Z No. of bitstreams: 3 Dissertação - Roberta Machado de Oliveira Frota Curado - 2015.pdf: 1412350 bytes, checksum: 3488f3ea9d285b268adb991ca619df94 (MD5) anexos - dissertacao - roberta m de o f curado.pdf: 1349907 bytes, checksum: d9adb8c0cfdeca8fe004bc23cde29b9b (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2015-10-28T14:56:17Z (GMT) No. of bitstreams: 3 Dissertação - Roberta Machado de Oliveira Frota Curado - 2015.pdf: 1412350 bytes, checksum: 3488f3ea9d285b268adb991ca619df94 (MD5) anexos - dissertacao - roberta m de o f curado.pdf: 1349907 bytes, checksum: d9adb8c0cfdeca8fe004bc23cde29b9b (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2015-10-28T14:56:17Z (GMT). No. of bitstreams: 3 Dissertação - Roberta Machado de Oliveira Frota Curado - 2015.pdf: 1412350 bytes, checksum: 3488f3ea9d285b268adb991ca619df94 (MD5) anexos - dissertacao - roberta m de o f curado.pdf: 1349907 bytes, checksum: d9adb8c0cfdeca8fe004bc23cde29b9b (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2015-02-05 / Fundação de Amparo à Pesquisa do Estado de Goiás - FAPEG / Male infertility affects about half of couples with infertility history and is considered a multifactorial syndrome, including a broad spectrum of diseases. Chromosomal abnormalities are a major cause of human infertility and interfere with spermatogenesis. Infertility in patients with Klinefelter's syndrome (KS) is a consequence of degeneration of germ cells and that affects about 4% of infertile men. Objective: To investigate the presence of chromosomal abnormalities in infertile men with azoospermia or oligozoospermia seen at the Human Reproduction Laboratory of the Hospital das Clinicas (LabRep -HC) of the Federal University of Goiás, in 2013. Methodology: Descriptive study. Metaphases were analyzed in GTG bands obtained from lymphocytes cultures of 20 infertile men idiopathic causes. Results: The patients' ages ranged from 26-59 years and the design attempts ranged on average of 5 (± 5.02) years. In 3/20 (15%) patients were found karyotype 47, XXY (SK) and the rest, 17/20 patients had a normal karyotype. Conclusion: Genetic testing can help identify which patients would benefit from the technical reproduction. These studies are relevant because the assisted reproduction techniques ignore the process of natural selection and some classic chromosomal abnormalities end some deleterious mutations that could through generations. Thus, genetic assessment can lead to genetic counseling and hence the primary and secondary prevention of congenital defects in offspring of patients with male infertility. This study helps to assess the prevalence of chromosomal abnormalities in some men treated at LabRep - HC UFG. / A infertilidade masculina afeta cerca da metade dos casais com histórico de infertilidade e é considerada uma síndrome multifatorial, incluindo um amplo espectro de doenças. As anormalidades cromossômicas são uma das principais causas de infertilidade humana e interferem na espermatogênese. A infertilidade em indivíduos com a síndrome de Klinefelter (SK) é uma consequência da degeneração de células germinativas e acomete cerca de 4% dos homens com infertilidade. Objetivo: Investigar a presença de anormalidades cromossômicas de homens inférteis com azoospermia ou oligozoospermia, atendidos no Laboratório de Reprodução Humana do Hospital das Clínicas (LabRep -HC) da Universidade Federal de Goiás, no ano de 2013. Metodologia: Estudo descritivo. Foram analisadas metáfases em bandas GTG obtidas a partir de cultura de linfócitos de 20 homens inférteis de causas idiopáticas. Resultados: A idade dos pacientes variou de 26-59 anos e as tentativas de concepção variaram em média de 5 (± 5,02) anos. Em 3/20 (15%) pacientes foi encontrado cariótipo 47,XXY (SK) e o restante, 17/20 pacientes, apresentaram cariótipo normal. Conclusão: Os testes genéticos podem ajudar a identificar quais pacientes poderiam ser beneficiados com as técnicas de reprodução. Estes estudos são relevantes, pois as técnicas de reprodução assistida ignoram o processo de seleção natural e algumas anormalidades cromossômicas clássicas ou algumas mutações deletérias que poderiam ser herdadas. Desta forma, a avaliação genética pode levar ao aconselhamento genético e, consequentemente, à prevenção primária e secundária dos defeitos congênitos nos descendentes dos pacientes com infertilidade masculina. O presente estudo contribui para avaliar a prevalência de anormalidades cromossômicas de alguns homens atendidos no LabRep - HC da UFG.

Leishmania est un parasite eucaryote divergent responsable d’un large spectre de maladies à travers le monde. Ce parasite est caractérisé par une aneuploïdie mosaïque, constitutive, c’est-à-dire qu’au sein d’une population chaque cellule comporte une combinaison unique de mono-, di- et trisomies de chacun de ses 36 chromosomes. L’aneuploïdie mosaïque est générée et maintenue chez les générations suivantes grâce à un taux élevé de répartition asymétrique des chromosomes lors de la mitose, entrainant le gain ou la perte de chromosomes entiers. Ceci implique une régulation non-conventionnelle de la réplication, suivie d’une ségrégation permissive des chromosomes.L’objectif général de cette étude était de comprendre la dynamique de la réplication de l’ADN ainsi que de cartographier les sites d’initiation de la réplication chez Leishmania, en utilisant la technique du peignage moléculaire d’une part et celle du ChIP-seq d’une autre part. Nous avons ainsi pu caractériser les différents paramètres de progression de la fourche de réplication. Un des résultats majeurs qui ressort de cette étude est que Leishmania possède les plus grandes distances inter-origines et la plus grande vitesse de réplication parmi les autres eucaryotes déjà étudiés. Nous avons également pu estimer que le génome de Leishmania possède environ 168 origines de réplication. Afin d’étudier les acteurs impliqués dans la réplication de l’ADN chez Leishmania, nous avons développé l’outil génétique CRISPR/Cas9. Pour développer cet outil, nous avons basé notre approche sur une stratégie à deux vecteurs : l’un permet l’expression du single guide (sg)RNA et l’autre celle de l’endonucléase Cas9. La validation de cet outil génétique a été réalisée par le knock-out du locus PFR2 codant une protéine flagellaire. Dans un second temps, nous avons fait évoluer le CRISPR/Cas9 vers un système inductible pour réaliser les knock-out et des étiquetages au locus endogène de protéines d’intérêt. Nous avons utilisé ce nouveau système pour étudier la fonction de deux protéines potentiellement impliquées dans le complexe de reconnaissance des origines de réplication. Malgré une fuite du système, nous avons pu réaliser le KO des gènes Orc1b et Orc1/Cdc6 et suivre la progression du cycle cellulaire. Nous avons pu constater que la perte de ces gènes conduisait à un défaut de croissance ainsi qu’à l’apparition de cellules sans noyau. L’insertion d’une étiquette au locus endogène d’Orc1b nous a parmi de confirmer la localisation que nous avions obtenue avec une construction épisomale et va permettre d’étudier plus précisément le rôle de cette protéine.En conclusion, nous avons mis en évidence des paramètres de réplication originaux et démontré, en utilisant le CRISPR/Cas9, que les protéines Orc1b et Ocr1/Cdc6 étaient impliquées dans la duplication du noyau de Leishmania, ce qui est en accord avec leur rôle putatif dans la réplication de l’ADN. / Leishmania, a protozoan parasite which causes a large range of diseases worldwide, is characterized by a constitutive 'mosaic aneuploidy', i.e. each cell in a population possesses a unique combination of mono-, di- and trisomies for each of its 36 heterologous chromosomes. Mosaic aneuploidy is generated and maintained via high rates of asymmetric chromosomal allotments during mitosis, leading to the gain or loss of whole chromosomes. This implies an unconventional regulation of the replication, followed by a permissive segregation.The main objective of this study was to unravel DNA replication dynamics and to map the replication initiation sites in Leishmania using DNA combing and ChIP-seq analyses. First, we have characterized DNA replication fork parameters. One of the major findings of this study was that Leishmania exhibits the fastest replication speed and the largest interorigin distances among the eukaryotes tested so far. We have also estimated that the Leishmania major genome possesses 168 origins of replication.To study the actors involved in DNA replication, we first had to develop novel genetic tools. The CRISPR/Cas9 (clustered regularly interspaced short palindromic repeats and CRISPR associated endonuclease 9) system is a recently discovered powerful technique for genome editing. In order to adapt this system to Leishmania, we have chosen a two-plasmid strategy: one for the expression of the single guide (sg) RNA and a second for the expression of the endonuclease CAS9. The proof of concept has been based on the disruption of the paraflagellar rod-2 (PFR2) loci by the CRISPR-Cas9 system. In a second attempt, we have developed an inducible CRISPR-Cas9 system, both to obtain knock outs and to perform marker-free endogenous gene tagging. We used the system to investigate the function of Origin Recognition Complex proteins. Although the system was leaky, the genome was edited as expected. We thus deleted Orc1b and Orc1/Cdc6 and monitored the cell cycle progression of the parasite. We found that the depletion of these nuclear proteins lead to a growth defect and to the appearance of zoids (anucleated cells). The endogenous tagging of Orc1b confirmed the localization previously obtained using an episomal expression vector, and will allow further investigation on the role of this protein.In total, we have shown the presence of original replication dynamics parameters in Leishmania, and using CRISPR Cas9, we have demonstrated that Orc1b and Orc1/Cdc6 are involved in the nuclear duplication of Leishmania, in agreement with their putative in DNA replication.

Muitas evidências indicam que a tumorigênese em humanos é um processo com várias etapas. A progressão de um tumor em direção a malignidade ocorre de maneiras muito distintas entre os diferentes tipos de câncer. Entender os processos celulares que levam a tumorigênese é importante para se delinear tratamentos mais adequados contra os diversos tipos de câncer. Drogas antimitóticas (ou venenos de fuso) são utilizadas no tratamento de alguns cânceres, e entre eles está o câncer de mama. A ação dessas drogas reside sobre a mitose, e têm como alvo os fusos mitóticos, estruturas essenciais que dirigem o ciclo celular na divisão das células. Recentemente, pesquisadores têm delineado possíveis respostas da célula aos venenos de fuso, e essas respostas são dependentes da concentração da droga. Baixas concentrações de venenos de fuso provocam o aparecimento de populações celulares aneuplóides, que ocorrem quando a célula sai do bloqueio mitótico. O presente trabalho utilizou as drogas vincristina e paclitaxel sobre linhagens celulares de mama humana (células normais e tumorais) para pesquisar se as drogas são capazes de induzir células aneuplóides. Os resultados obtidos no presente trabalho indicam que baixa concentração de vincristina e paclitaxel pode induzir o aparecimento de população aneuplóide através de mitoses aberrantes. Os venenos de fuso induzem a formação de mitoses contendo múltiplos fusos mitóticos, e essas mitoses não ficam bloqueadas, dando origem a células aneuplóides. O papel da aneuploidia na tumorigênese não foi ainda estabelecido, mas indiferente da sua importância no desenvolvimento do tumor, encontrar maneiras de inibir sua formação ou de super induzir seu aparecimento podem ter implicações significativas para as terapias contra o câncer. / Several lines of evidence indicate that tumorigenesis in humans is a multistep process and that these steps reflect genetic alterations that drive the progressive transformation of normal cells into highly malignant derivatives. Understanding the cellular processes that lead to tumorigenesis is important to devise more appropriate treatments against various types of cancer. Antimitotic drugs are used in the treatment of some cancers, and among them is breast cancer. The action of these drugs lies on the mitotic spindles, essential structures that drive the cell cycle in the division of cells. Recently, researchers have outlined possible responses to the antimitotic drugs on cells, and these responses are dependent on the concentration of the drug. Low concentrations of drugs can cause the appearance of aneuploid population, which occur when a cell leaves the mitotic block. This study used the drug vincristine and paclitaxel on human breast cancer cell lines (normal and tumoral cells) to find if the drugs are capable of inducing cell aneuploidy. The results of this study indicate that low concentration of vincristine and paclitaxel can induce the emergence of aneuploidy population through aberrant mitosis. The drugs induce the formation of mitosis containing multiple mitotic spindles, resulting in aneuploidy population of cells. The role of aneuploidy in tumorigenesis has not yet been established, but indifferent to this is important find ways to inhibit its formation or the super-induce their appearance. These questions may have significant implications for therapies against cancer.

Flödescytometrisk analys av DNA-ploiditeten används vid diagnostisering av endometriecancer. DNA-ploidi reflekterar cellcykeln och avgör om tumörens cellpopulationen är diploid eller aneuploid, där aneuploiditet förknippas med sämre prognos. Vid analys av paraffininbäddat vävnadsmaterial används avparaffineringsmedlet xylen, vars toxiska egenskaper försämrar arbetsmiljön på laboratoriet. Den har en stark och obehaglig lukt som kan orsaka illamående och yrsel. Syftet med studien var att undersöka om xylen kan ersättas med xylensubstitutet Tissue Clear, ett isoparaffinskt kolväte som är mindre toxiskt. Studien omfattade paraffininbäddad humanvävnad från endometrioid carcinom (n=20), både diploid (n=15) och aneuploid (n=5) vävnad, som avparaffinerades med xylen respektive Tissue Clear innan DNA-ploidi utfördes. Eventuella skillnader inom de flödescytometriska parametrarna % CV-diploid, % S-fas, % debris och DI-aneuploid undersöktes och vid statistisk analys kunde ingen signifikant skillnad ses på samtliga parametrar. Eftersom analysen utförs sällan i rutin är antalet prover i studien relativt stor, trots att detta kan anses vara en liten kvantitet. Av dessa var endast 25 % av proverna aneuploida. Att en patient uppvisar aneuploiditet är ovanligt och därför ansågs även denna mängd som tillräckligt stor. Studien visar att avparaffinering med Tissue Clear är ekvivalent med xylen och därmed kan Tissue Clear ersätta xylen oavsett om vävnaden är diploid eller aneuploid. / DNA ploidy is used for endometrial cancer diagnosis. It reflects the cell cycle and determines whether the cell population in tumors is diploid or aneuploid. When analyzing paraffin embedded tissues xylene can be used for deparaffinization, whose toxicity impairs the laboratory´s work environment. Its strong and unpleasant smell can cause nausea and dizziness. The aim of this study was to investigate if xylene can be replaced with Tissue Clear, an isoparaffinic hydrocarbon that is less toxic. The study included paraffin embedded human tissues from endometrioid carcinoma (n=20), both diploid (n=15) and aneuploid (n=5), deparaffinized with xylene or Tissue Clear before DNA ploidy was performed. Potential differences between the parameters % CV-diploid, % S-phase, % debris and DI-aneuploid were statistically examined and showed no significant differences. The sample amount in this study might be considered low, though it is relatively high since the analysis is rarely performed routinely. Among these only 25 % were aneuploid. Patients showing aneuploidy is rare and the amount was therefore considered to be sufficient as well. The study shows that deparaffinization with Tissue Clear generates equivalent results as for xylene and can thereby replace xylene regardless if the tissue is diploid or aneuploid.

Une caractéristique intéressante de la protéine Bcl-xL est la présence d'un domaine en boucle non-structurée entre les hélices α1 and α2 de la protéine. Ce domaine protéique n'est pas essentiel pour sa fonction anti-apoptotique et absent chez CED-9, la protéine orthologue chez Caenorhabditis elegans. A l'intérieur de ce domaine, Bcl-xL subit une phosphorylation et déphosphorylation dynamique sur les résidus Ser49 et Ser62 en phase G2 du cycle cellulaire et lors de la mitose. Lorsque ces résidus sont mutés et les protéines exprimées dans des cellules cancéreuses, les cellules démontrent plusieurs défauts mitotiques liés à l'instabilité chromosomique. Pour analyser les effets de Bcl-xL Ser49 et Ser62 dans les cellules normales, les présentes études ont été réalisées dans des cellules diploïdes humaines normales, et in vivo chez Caenorhabditis elegans. Dans une première étude, nous avons utilisé la lignée cellulaire de cellules fibroblastiques diploïdes humaines normales BJ, exprimant Bcl-xL (type sauvage), (S49A), (S49D), (S62A), (S62D) et les double (S49/62A) et (S49/62D) mutants. Les cellules exprimant les mutants de phosphorylation ont montré des cinétiques de doublement de la population cellulaire réduites. Ces effets sur la cinétique de doublement de la population cellulaire corrèle avec l'apparition de la sénescence cellulaire, sans impact sur les taux de mort cellulaire. Ces cellules sénescentes affichent des phénotypes typiques de sénescence associés notamment à haut niveau de l'activité β-galactosidase associée à la sénescence, la sécrétion d' interleukine-6, l'activation de p53 et de p21WAF1/ Cip1, un inhibiteur des complexes kinase cycline-dépendant, ainsi que la formation de foyers de chromatine nucléaire associés à γH2A.X. Les analyses de fluorescence par hybridation in situ et des caryotypes par coloration au Giemsa ont révélé que l'expression des mutants de phosphorylation de Bcl-xL provoquent de l'instabilité chromosomique et l'aneuploïdie. Ces résultats suggèrent que les cycles de phosphorylation et déphosphorylation dynamiques de Bcl-xL Ser49 et Ser62 sont importants dans le maintien de l'intégrité des chromosomes lors de la mitose dans les cellules normales. Dans une deuxième étude, nous avons entrepris des expériences chez Caenorhabditis elegans pour comprendre l'importance des résidus Ser49 et Ser62 de Bcl-xL in vivo. Les vers transgéniques portant les mutations de Bcl-xL (S49A, S62A, S49D, S62D et S49/62A) ont été générés et leurs effets ont été analysés sur les cellules germinales des jeunes vers adultes. Les vers portant les mutations de Bcl-xL ont montré une diminution de ponte et d'éclosion des oeufs, des variations de la longueur de leurs régions mitotiques et des zones de transition, des anomalies chromosomiques à leur stade de diplotène, et une augmentation de l'apoptose des cellules germinales. Certaines de ces souches transgéniques, en particulier les variants Ser/Ala, ont également montré des variations de durée de vie par rapport aux vers témoins. Ces observations in vivo ont confirmé l'importance de Ser49 et Ser62 à l'intérieur du domaine à boucle de Bcl-xL pour le maintien de la stabilité chromosomique. Ces études auront une incidence sur les futures stratégies visant à développer et à identifier des composés qui pourraient cibler non seulement le domaine anti-apoptotique de la protéine Bcl-xL, mais aussi son domaine mitotique pour la thérapie du cancer. / An interesting feature of Bcl-xL protein is the presence of an unstructured loop domain between its α1 and α2 helices, a domain not essential for its anti-apoptotic function and absent in CED-9, ortholog protein in Caenorhabditis elegans. Within this domain, Bcl-xL undergoes dynamic phosphorylation and dephosphorylation at Ser49 and Ser62 during G2 and mitosis in human cancer cells. When these residues are mutated and proteins expressed in cancer cells, cells harbor mitotic defects, including chromosome mis-attachment, lagging, bridging and mis-segregation, events associated with chromosome instability and aneuploidy. To further analyze the effects of Bcl-xL Ser49 and Ser62 in normal cells, the present studies were performed in normal human diploid cells, and in vivo in Caenorhabditis elegans. First, we studied normal human diploid BJ foreskin fibroblast cells expressing Bcl-xL(wild type), (S49A), (S49D), (S62A), (S62D) and the dual (S49/62A) and (S49/62D) mutants. Cells expressing S49 and/or S62 phosphorylation mutants showed reduced kinetics of cell population doubling. These effects on cell population doubling kinetics correlated with early outbreak of senescence with no impact on the cell death rate. Senescent cells displayed typical senescence-associated phenotypes including high-level of senescence-associated β-galactosidase activity, interleukin-6 secretion, tumor suppressor p53 and cyclin-dependent kinase inhibitor p21Waf1/Cip1 activation as well as γH2A.X-associated nuclear chromatin foci. Fluorescence in situ hybridization analysis and Giemsa-banded karyotypes revealed that the expression of Bcl-xL phosphorylation mutants in normal diploid BJ cells provoked chromosome instability and aneuploidy. These findings suggest that dynamic Bcl-xL Ser49 and Ser62 phosphorylation/ dephosphorylation cycles are important in the maintenance of chromosome integrity during mitosis in normal cells. Second, we undertook experiments in Caenorhabditis elegans to understand the importance of Bcl-xL Ser49 and Ser62 in vivo. Transgenic worms carrying single-site S49A, S62A, S49D, S62D and dual-site S49/62A mutants were generated and their effects were analyzed in germlines of young adult worms. Worms expressing Bcl-xL variants showed decreased egg-laying and hatching, variations in the length of their mitotic regions and transition zones, chromosomal abnormalities at their diplotene stages, and increased germline apoptosis. Some of these transgenic strains, particularly the Ser to Ala variants, also showed slight modulations of lifespan compared to their controls. The in vivo observations confirmed the importance of Ser49 and Ser62 within the loop domain of Bcl-xL in maintaining chromosome stability. These studies could impact future strategies aiming to develop and identify compounds that could target not only the anti-apoptotic domain of Bcl-xL protein, but also its mitotic domain for cancer therapy.

Alterações no genoma de células tumorais são eventos comuns durante a carcinogênese. Tais aberrações genômicas - como mutações e variações estruturais - são diretamente relacionadas a detecção e morte de células neoplásicas pelo sistema imune. Além da contribuição da perda de função de genes supressores tumorais (GSTs) no desenvolvimento neoplásico, GSTs também influenciam a resposta imune no câncer. Por exemplo, o GST PTEN afeta diretamente a via interferon através da desfosforilação do fator regulador de interferon 3 (IRF3). No entanto, se mantém inconclusivo se a inativação de PTEN diretamente influencia a resposta imune através de IRF3 ou por provocar altos níveis de instabilidade genômica. Para responder essa questão, conduzimos uma análise PanCancer de 33 tipos tumorais da coorte The Cancer Genome Atlas para identificar se existem associações entre a inativação do gene PTEN e alterações genômicas específicas que podem suprimir ou ativar a resposta imune antitumoral. O status de inativação de PTEN foi determinado a partir de dados de variação no número de cópias e presença de mutações de ponto. Nesse estudo, investigamos o efeito da inativação de PTEN nas alterações genômicas de tumores e na abundância de 22 células do sistema imune derivadas do algoritmo CIBERSORT. Observamos que a inativação de PTEN foi significantemente associada com níveis elevados de aneuploidia, mutações, e heterogeneidade intratumoral. Além disso, nossos achados mostraram que a inativação de PTEN é altamente específica para cada tipo tumoral. Da mesma maneira, observamos que pacientes com tumores PTEN-inativos podem apresentar variações na resposta a imunoterapia. Tal observação deriva da correlação significativa entre a inativação de PTEN e a expressão dos alvos terapêuticos proteína programada 1 da morte celular (PD1), seu ligante (PDL1), e indoleamina 2,3 dioxigenase (IDO1). Na análise PanCancer, a inativação de PTEN também foi significativamente associada à composição de células do sistema imune no microambiente tumoral, incluindo células T regulatórias (Treg) e células CD8+. A partir desses achados, conduzimos uma análise aprofundada de tumores de próstata primários e metastáticos com a perda de PTEN. Através de uma análise in silico, nós observamos que tumores primários e metastáticos apresentam maiores densidades de Treg quando há perda da proteína PTEN. Nós também observamos que, dependendo do local de metástase prostática, a deficiência de PTEN é associada a um perfil de células imunes supressivas no microambiente tumoral. A partir da análise de uma coorte brasileira composta por 94 tumores primários de próstata, observamos que a perda de PTEN se associa a uma maior densidade de Tregs e uma maior expressão da proteína imunossupressora IDO1. Além disso, tumores PTEN-deficientes com altas densidades de Tregs apresentaram o pior prognóstico entre pacientes. Coletivamente, nós demonstramos que a inativação de PTEN é associada a um estado imunossuprimido no microambiente tumoral. Ademais, a perda de PTEN possivelmente se associa a resposta imune antitumoral através da combinação de duas diferentes vias - uma dependente de IRF3 e outra relacionada ao efeito no genoma de células cancerosas. Ensaios funcionais são necessários para validar os achados desse estudo; porém, sugerimos que a avaliação do status de inativação de PTEN pode ter alto potencial para discernir pacientes que responderão à imunoterapia. / Cancer-cell genomes undergo several abnormalities during carcinogenesis. Indeed, many of the tumor-specific genomic changes, such as mutations and chromosomal aberrations, are related to how the host immune system responds to detect and kill tumor cells. In addition to these general effects, loss of function of specific tumor suppressor genes (TSG) contributes to tumor development and progression and at the same time also regulates several facets of the immune response in cancer. For instance, the TSG phosphatase and tensin homolog (PTEN) was shown to directly regulate the anti-viral interferon response by licensing the interferon regulatory factor 3 (IRF3). However, it is still unclear whether PTEN directly influences the immune response through the interferon network or by provoking higher levels of genomic instability. To address this question, we conducted a PanCancer analysis of 33 tumor types from The Cancer Genome Atlas to determine whether there were associations between PTEN inactivation and specific genomic features that are linked to immunosuppressive states in cancer. PTEN inactivation status was determined by combining copy number and point mutation data. Then, we performed a parallel analysis of genomic instability and immune-cell abundances derived from the CIBERSORT algorithm comparing PTEN deficient to intact tumors. We found that PTEN inactivation was strongly associated with enhanced levels of aneuploidy, mutation load, immunogenic mutations, and tumor heterogeneity. Furthermore, we found that the outcome of PTEN inactivation status was highly specific to each tumor type and the induced changes appeared to lead to variation in immune responses in different cancers. Response to current immunotherapeutic approaches depends on the expression of targeted immune checkpoints, and we found that tumors with PTEN deficiency had altered expression of programmed death protein 1 (PD1), its ligand (PDL1), and the immunosuppressive protein indoleamine 2,3-dioxygenase (IDO1). We also found that PTEN inactivation led to a distinct immune-cell composition in the tumor microenvironment, including regulatory T cells and CD8+ T cells. Lastly, we performed an in-depth analysis of the immune-cell content of prostate tumors that harbored PTEN protein loss. Through an in silico analysis of 622 tumors, we found that both primary and metastatic lesions had higher densities of regulatory T cells when PTEN was lost. Then, the analysis of 94 primary prostate tumors from Brazil demonstrated that PTEN protein loss was significantly associated with high Treg density and IDO1 protein expression. Moreover, PTEN-null tumors with high Treg density exhibited the worse outcome among patients. We also found that, depending on the prostate cancer metastatic site, PTEN deficiency was linked to variation in the immunosuppressive immune cell landscape. Collectively, we show that PTEN inactivation associates with the anti-tumor immune response likely through direct avenues (via licensing of IRF3) and indirectly by influencing the genome of cancer cells. Functional studies are required to validate our in silico findings; however, we speculate that determining PTEN inactivation status may allow clinicians to distinguish patients that are more likely to respond to current immunotherapies.

Noventa e sete fetos portadores de fenda facial diagnosticados entre Maio de 1995 e Novembro de 2004 foram avaliados no setor de medicina fetal da Clínica Obstétrica do Hospital das clinicas da universidade de São Paulo.Houve excelente correlação entre o tipo de fenda facial diagnosticada pela ultra-sonografia no período gestacional e o tipo de fenda facial observado no pós-natal. A avaliação do palato foi o maior problema técnico para o diagnóstico da fenda facial. A idade gestacional no diagnóstico da fenda facial foi tardia. Fetos com fenda facial isolada apresentaram excelente prognóstico e fetos com outras malformações apresentaram alta taxa de mortalidade independente de presença de aneuploidia / Ninety seven fetuses presenting facial cleft diagnosed from May 1995 to November 2004 at the Fetal Medicine Unit of the Obstetric Clinic at University of São Paulo Medical School Hospital were reviewed. An excellent correlation was found between the type of prenatally diagnosed cleft and the type of cleft observed after birth. Palate integrity evaluation was the main technical limitation of prenatal ultrasound. Diagnosis of the facial cleft occurred late in pregnancy in this series. Fetuses with isolated facial cleft had an excellent prognosis and fetus with other malformations presented very high mortality rate independently of the presence of chromosomal abnormality

A pesquisa de marcadores ultrassonográficos no segundo trimestre da gestação, após rastreamento combinado no primeiro, parece elevar substancialmente as taxas de detecção de Síndrome de Down, mas está amparada na assunção não comprovada de independência entre esses testes. O presente estudo investigou a relação entre a translucência nucal e uma série de marcadores ultrassonográficos no segundo trimestre. A medida da translucência nucal no primeiro trimestre era seguida pela realização da ultrassonografia morfológica entre 18 a 23 semanas e 6 dias de gestação, incluindo a pesquisa de três marcadores qualitativos (foco ecogênico intracardíaco, intestino hiperecogênico e defeito estrutural) e as medidas do osso nasal, da prega nucal, do comprimento do úmero, do comprimento do fêmur, do diâmetro anteroposterior das pelves renais e da espessura pré-nasal. Todas as variáveis contínuas foram expressas em múltiplos da mediana para a idade gestacional e os coeficientes de correlação entre a translucência nucal e essas variáveis (após transformação logarítmica) foram calculados. Em seguida, as frequências de marcadores clássicos no segundo trimestre, em casos com translucência nucal normal, foram comparadas àquelas com translucência nucal aumentada, usando pontos de corte definidos em múltiplos da mediana. Em população prospectiva de 1970 casos, a translucência nucal se correlacionou significativamente com todas as variáveis ultrassonográficas do segundo trimestre, em particular, com a prega nucal (r=0.10). Houve frequência significativamente maior de casos com prega nucal aumentada (10,7 versus 2,2%), definida como valor (em MoMs) acima do percentil 97,5, e intestino hiperecogênico (2,4% versus 0,1%) em casos com translucência nucal aumentada. Concluindo, a utilização de razões de verossimilhança baseadas na presença, ou ausência, de marcadores ultrassonográficos no segundo trimestre para modificar o risco calculado, no primeiro trimestre, poderia deteriorar a precisão das estimativas. Técnicas multivariadas por meio de marcadores ultrassonográficos quantitativos seriam opção mais adequada para a implantação de estratégias de rastreamento sequenciais / Genetic sonogram following first trimester combined screening appears to substantially increase detection rates for Down syndrome but it relies on the unproved assumption of independence between these tests. In this study we have investigated the relation of first trimester nuchal translucency to a series of secondtrimester soft markers. Nuchal translucency (NT) measurement in the first trimester was followed by second trimester scan (18-23w+6 days) including search for three categorical soft-markers (intracardiac echogenic foci, hyperechogenic bowel and structural defects) and measurements of nasal bone length, nuchal fold thickness, femur length, humerus length, renal pelvices diameter and prenasal thickness. All continuous variables were expressed in multiples of the medians for gestation (MoMs) and correlation coefficients between log-transformed NT and second trimester variables were calculated. In addition, frequencies of classical soft-markers in cases with increased NT were compared to those with normal NT, using MoMs cutoffs. In a dataset of 1970 cases, NT was significantly correlated (p<0.05) to all second trimester continuous variables, in particular to nuchal fold thickness (r=0.10). There was a higher frequency of cases with second trimester nuchal fold thickness above the 95th centile (10.7% versus 2.2%) and hyperechogenic bowel (2.4% versus 0.1%) in cases with increased NT. In conclusion, straightforward reassessment of risk using likelihood ratios derived from the classical genetic sonogram might lead to inaccurate estimates. Multivariate models using continuous second-trimester variables might be preferable in sequential screening strategies