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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

The roles of p63 as a key transcriptional regulator in epidermal homeostasis / Rôles de p63, un régulateur transcriptionnel clé de l'homéostasie épidermique

Wu, Ning 24 June 2010 (has links)
La couche externe de la peau humaine, l’épiderme, est un tissue épithélial auto-renouvelable, stratifié et squameux. Chez l’adulte, la maintenance de l’homéostasie de l’épiderme dépend de la régulation de la balance entre la prolifération et la différenciation des keratinocytes. Cependant, les mécanismes moléculaires qui contrôlent ces processus ne sont pas encore complètement élucidés. P63 (TP63), un membre de la famille p53, agit comme régulateur clé de la balance prolifération/différenciation des cellules épithéliales en général et des kératinocytes humains en particulier. Malgré les connaissances acquises sur p63 ces dernières années, les mécanismes moléculaires agissant en aval de p63 pour contrôler l’homéostasie épidermique, restent à découvrir. L’analyse des changements transcriptionnels et phénotypiques induit par l’extinction transitoire de p63 ou de MYC dans les keratinocytes humains matures, nous a permis d’identifier les réseaux de gènes agissants en aval de ces deux protéines pour le contrôle de l’homéostasie. Nous avons montré que p63 est impliqué dans le maintien de la prolifération cellulaire et le déclenchement de la différenciation des kératinocytes par deux mécanismes distincts. L’ablation de p63 provoque un défaut d’expression de MYC via les voies de signalisation Wnt/-catenin et Notch et par conséquent réduit la prolifération des keratinocytes. En autre, p63 agit sur la prolifération des keratinocytes en réprimant directement l’expression de la protéine ID2. Nous avons aussi caractérisé un réseau KCF (Keratinocyte Cell Fate) contrôlé par p63, qui déclenche la différenciation. Ce réseau contient plusieurs protéines secrétées, impliquées dans la migration/adhésion cellulaires, telles que la fibronectine (FN1), l’interleukine 1 beta (IL1B), la cysteine-rich protein 61 (CYR61) et jagged-1 (JAG1) qui agissent en aval de p63 pour promouvoir la différenciation. Finalement, nous avons caractérisé un ensemble de miRNAs contrôlés par p63, et démontré leur capacité à engager la différenciation terminale des keratinocytes. Ces miRNAs ciblent de nombreuses MAPKs, qui jouent un rôle important dans la différenciation keratinocytaire. Nous avons montré que l’inhibition des MAPKs peut même restaurer le défaut de différenciation observé en absence de p63. Mon travail de thèse a permis l’émergence d’une vision générale des “effecteurs de la différenciation”: gènes codants des protéines ou des miRNA. Ces gènes agissent en aval de p63 pour réguler la prolifération ou enclencher la différenciation terminale des keratinocytes. / The outer layer of human skin, the epidermis, is a self-renewing, stratified squamous epithelial tissue. In adult tissue, the maintenance of epidermal homeostasis depends on an exquisite regulation of the balance between keratinocyte proliferation and differentiation. However, the specific molecular mechanisms governing each of these processes are not completely understood. p63 (TP63), a member of tumor suppressor p53 family, acts as a key regulator in controlling proliferation and differentiation balance in human keratinocytes. Although our knowledge of p63 was tremendously extended in the past years, little is known on the molecular mechanisms downstream of p63 that regulate the epidermal homeostasis. The identification of functional “effectors” acting downstream of p63 is an open question. By analyzing the transcriptional changes and phenotypic consequences of the loss of either p63 or MYC in human mature keratinocytes, I have characterized the networks acting downstream of these two genes to control epidermis homeostasis. I have shown that p63 is required to maintain growth and to commit to differentiation by two distinct mechanisms. Knockdown of p63 led to downregulation of MYC via the Wnt/-catenin and Notch signaling pathways and in turn reduced keratinocyte proliferation. In addition, p63 controls the keratinocyte proliferation by directly repressing the transcription regulator of bHLH family, ID2. I demonstrated that a p63-controlled keratinocyte cell fate (KCF) network is essential to induce the onset of keratinocyte differentiation. This network contains several secreted proteins involved in cell migration/adhesion, including fibronectin 1 (FN1), interleukin 1 beta (IL1B), cysteine-rich protein 61 (CYR61), and jagged-1 (JAG1), that act downstream of p63 as key effectors to trigger differentiation. My findings establish for the first time a connection between p63 and MYC and show that the balance between MYC-controlled cell-cycle progression network and p63-controlled cell migration-related network dictate skin cell fate. Finally, I have characterized a set of miRNAs controlled by p63, and specified their roles in the onset of keratinocyte terminal differentiation. They target MAPKs, which have a strong effect on differentiation. Actually, inhibition of MAPKs was able to rescue the defects of differentiation caused by the loss of p63. My PhD work enabled the emergence of a general view on the “differentiation effectors”, both protein coding and non-coding small RNA genes, acting downstream of p63 to promote the commitment of human keratinocytes to terminal differentiation.
2

P63 and cleft lip : expanding the P63 network

Sullivan, Robert James Tyrer January 2016 (has links)
Cleft lip and palate is a developmental abnormality which affects 1 in 500 live births resulting in considerable morbidity for the affected individual and their families and providing an economic burden to the state. Human mutations in TP63 have been shown to induce at least five developmental syndromes which are characterised by the presence of orofacial clefting, malformed limbs and defects in ectoderm-derived tissues. Mouse models of Trp63 knockout display phenotypes similar to the clinical manifestation of TP63 human mutations. To date the majority of orofacial P63-related research has focussed on secondary palate development, as such the role of P63 during upper lip development remains poorly characterised. Upper lip development is similar between mouse and human. The medial nasal, lateral nasal and maxillary processes form as outgrowths of the frontonasal prominence. Directed growth of the facial processes results in their epithelial contact and adhesion. At the site of epithelial contact a double epithelial seam is formed, which must be degenerated to allow mesenchymal confluence across the upper lip. Trp63 has been shown to be expressed within the epithelia of the facial processes throughout upper lip development, with expression detected during process outgrowth, contact and adhesion. Down-regulation of Trp63 expression within the epithelial seams is followed by seam degeneration and upper lip fusion. Furthermore, the cleft lip and palate phenotype of TP63-related conditions suggests P63 plays a key role in upper lip morphogenesis. Previous studies have identified P63 target genes using high throughput methods. However, P63 functions in a tissue specific manner and so the applicability of these studies to upper lip development is hampered by their choice of model tissue. The aim of this study was therefore to identify targets of P63-regulation in upper lip development using stage appropriate tissue. High throughput methods were used to identify sites of P63 binding and genes misregulated in Trp63-/- mouse facial processes. Via characterisation of putative target genes a novel role for P63 in the regulation of Wnt and Fgf signalling during upper lip morphogenesis was identified. It is therefore suggested that during upper lip morphogenesis P63 regulates the expression of multiple members of the Wnt and Fgf signalling family to maintain the proliferative and differentiation potential of the facial processes. Furthermore regulation of Wnt and Fgf signalling provides a mechanism by which P63 may regulate epithelial to mesenchymal signalling. This project has identified potential novel targets of P63 regulation during upper lip development, in addition to providing a novel mechanism of P63 regulation of wider relevance to the embryological development of multiple tissues.
3

Effects of season and plane of nutrition upon serum lipids and protein of white-tailed deer

Porterfield, Thomas Randall January 1970 (has links)
Blood samples were collected from 80 wild deer in four areas of the southeastern United States, and from 50 captive deer on three levels of nutrition at Pennsylvania State University. Blood lipids were fractionated by thin layer chromatography; serum proteins were separated by electrophoresis on cellulose acetate strips; and proportional concentrations of lipid and protein fractions were determined by densitometry. Significant differences between seasons were found for fatty acids, lecithins, and alpha globulin in the wild deer. No tests for seasonal differences were made for captive deer. Three regression equations were developed to describe the data. The following equations were obtained by computer using the BMD-O2R packaged program. y = 35.3 - 7.0X₁ - 12.6X₂ + 1.5X₃ + 3.6X₄ + 0.3X₅ - 0.4X₆ where: y = body weight in kg. of wild deer X₁ = condition index¹ (a dummy variable) X₂ = condition index² (a dummy variable) X₃ = age in years X₄ = season¹ (a dummy variable) X₅ = polar lipids (percentage of total lipids) X₆ = cholesterol (percentage of total lipids) The multiple R² for the equation above was 0.57 y = -987.1 + 210.4X₁ - 1549X₂ where: y = mean weekly food intake by captive deer for a 2 month period prior to blood collection. (grams dry matter intake) X₁ = body weight in kg. of captive deer X₂ = season¹ (a dummy variable) The multiple R² for the second regression was 0.81. y = 50.8 - 7.3X₁ where: y = mean weekly digestible protein intake in grams by captive deer over a 2 month period prior to blood collection. X₁ = season¹ (a dummy variable) / Master of Science
4

CCDC3: A new p63 target gene involved in regulation of liver lipid metabolism

January 2016 (has links)
acase@tulane.edu / TAp63, a member of the p53 family, has been shown to regulate energy metabolism. Here, we report coiled coil domain-containing 3 (CCDC3) as a new TAp63 target. TAp63, but not ΔNp63, p53 or p73, induces the expression of CCDC3 mRNA level by directly binding to the p63 consensus DNA binding sequence within the CCDC3 enhancer region. The CCDC3 expression is markedly reduced in TAp63-null mouse embryonic fibroblasts and brown adipose tissues and by tumor necrosis factor alpha that reduces p63 transcriptional activity but induced by metformin, an anti-diabetic drug that activates p63. Also, the expression of CCDC3 is positively correlated with TAp63 levels, but inversely with ΔNp63 levels, during adipocyte differentiation. Interestingly, CCDC3, as a secreted protein, targets liver cancer cells and increases long chain polyunsaturated fatty acids, but decreases ceramide in the cells. CCDC3 alleviates glucose intolerance, insulin resistance, and fatty liver (steatosis) formation in transgenic CCDC3 mice on the high-fat diet by markedly reducing hepatic PPARγ expression and consequently leading to a drastic decrease of the PPARγ target gene, CIDEA, and other genes involved in de novo lipogenesis and of lipid droplets formation in their livers. Similar results are reproduced by hepatic expression of ectopic CCDC3 in mice on high-fat diet. Altogether, these results demonstrate that CCDC3 modulates liver lipid metabolism by inhibiting liver de novo lipogenesis as a downstream player of the p63 network. / 1 / Wenjuan Liao
5

The critical role of p63 during palatal shelf fusion

Richardson, Rose January 2015 (has links)
Cleft palate affects approximately 1 in 2000 live births resulting in considerable morbidity to affected individuals and their families. Evidence that the p63 gene is mutated in at least seven human developmental syndromes which are each characterised by varying extents of orofacial clefting, coupled to the severe facial dysmorphism displayed by the p63 mutant mouse, highlight the need to elucidate the role of the p63 during normal and aberrant palatogenesis. In mice, secondary palate development closely mirrors that occurring in humans; consequently, the mouse is a pre-eminent model organism for studying palatogenesis. In mice, the palatal shelves initiate from the maxillary processes and grow vertically, lateral to the tongue. The shelves re-orientate and make contact above the tongue. The medial edge epithelia (MEE) of the apposed palatal shelves adhere to form a midline epithelial seam (MES). Subsequent degeneration of the MES allows mesenchymal confluence across the palate, at which point palatogenesis is considered complete. The mechanisms underlying degeneration of the MES remain contentious; however, in vivo studies suggest that cessation of proliferation, induction of apoptosis and periderm migration are essential to ensure removal of the midline seam. The data presented in this thesis uncover a key role for p63 in controlling these aspects of cell behaviour during palatal shelf fusion. Tgfb3-/- mice exhibit cleft palate with maintained expression of p63 in the MEE. This thesis reveals that epistatically lowering the dosage of p63 in Tgfb3-/- mice rescues this fusion defect, facilitating periderm cell migration out of the MEE and subsequent MES degradation. Recent research suggests that p63 orchestrates a cell adhesion network in the palate. In this context, this thesis suggests the importance of p63 down-regulation in the MES in compromising adhesion at the basal-periderm border, thereby allowing periderm cell migration out from the midline and subsequent MES degradation. To test the hypothesis that down-regulation of p63 is essential for palatal fusion, tetracycline-inducible transgenic animals in which ΔNp63α is targeted to the MEE of the developing palate have been engineered. ΔNp63α bi-transgenic mice presented with cleft palate in which the MES failed to degenerate. An observed lack of apoptotic activity in the MEE of ΔNp63α bi-transgenic mice suggested a role for p63-mediated apoptosis during MES degradation. Gene ontology analysis of a complete range of ΔNp63α transcriptional targets which have been identified in the secondary palate by ChIP-seq, lent support to this hypothesis. The data indicate that p63 down-regulation in the MES is essential to ensure complete removal of the MES and implicate p63 as a key regulator of apoptosis during this process; thereby building on work which suggests that cell death is the major fate of the MEE. In addition to dissecting a pathway of fundamental importance in secondary palate development, this research provides insights into ectodermal development more generally and has wider significance for the study of many congenital malformations.
6

Crosstalk between high-risk human papillomavirus E7 and p63 in cervical cancer

Eldakhakhny, Sahar January 2018 (has links)
Introduction: Cervical cancer is the fourth most common malignancy diagnosed in women worldwide. It results from cellular transformation by the high-risk human papillomavirus (HPV) oncogenes E6 and E7, which accounts for more than 99% of diagnosed cases. HPV links its life cycle to epithelial proliferation and differentiation, which requires the cells to remain active in cell cycle. p63 modulates epithelial development as well as proliferation, differentiation and DNA damage response (DDR), which makes it an important target for HPV oncoproteins to allow viral replication and survival in infected cells. Methods: In this study, small interfering RNAs targeting E7 oncoprotein and p63 in the HPV16 positive cervical cancer cell line CaSki were used. Western blotting, proliferation assays, apoptosis assays and cell cycle analysis were applied to examine the effects of E7 and p63 depletion on cell fate. Overexpression of different types of HPV-E7 was performed in the N/Tert-1 keratinocyte cell line to study the effect of E7 overexpression on p63 level. Results: E7 drives the expression of p63 at both transcript and protein levels in cervical cancer cell lines. Downregulation of E7 is accompanied by a remarkable inhibition of cell proliferation and cell cycle arrest in the G0/G1 phase. Depletion of E7 is associated with a significant reduction in p63 expression which is not due to impaired proliferation or induced differentiation. Downregulation of p63 is associated with delayed DDR in cervical cancer cells following treatment with ionising radiation. High-risk HPV E7s are more potent in inducing p63 upregulation and increasing the proliferation rates in keratinocytes. Conclusion: This work for the first time demonstrated that E7 modulates the expression of p63, which regulates DNA damage repair pathways, that promotes efficient and rapid repair of the DNA damage following ionising radiation treatment in cervical cancer cells. Tumour recurrence due to resistance to radiotherapy is common, mostly due to promoted DNA repair ability of cancer cells to reduce radiation-induced toxicity and increase cell survival in response to ionising radiation. These findings might be the key to the development of radioresistance in cervical cancer. The HPV E7-p63 axis may be a novel therapeutic target to enhance radio-sensitivity in HPV-transformed tumours.
7

p63 – from expression to function : studies of normal oral mucosa and squamous cell carcinoma of the head and neck

Thurfjell, Niklas January 2007 (has links)
The human p63 gene discovered in 1997 encodes a series of protein isoforms that differ in their N- and/or C-terminal sequences. These isoforms have widely differing properties in promoting or repressing p53-related functions such as growth arrest and apoptosis. In addition, p63 appears to play important roles in the maintenance and differentiation of epithelial cell populations. Many studies have shown that p63, particularly Np63, is expressed in normal epithelium and also highly expressed in squamous cell carcinomas of surface epithelia. Methods. We have refined the analysis of the expression patterns of p63 isoforms by the use of a quantitative RT-PCR technique applied to micro-dissected normal oral mucosal samples. We have also studied p63 expression in squamous cell carcinoma of the head and neck (SCCHN) compared to normal oral mucosa taken from the same patient. Furthermore, tobacco-exposed buccal mucosa was compared to age and gender matched non exposed controls. RT-PCR for telomerase and immunohistochemical analysis for detection of p53 and Ki-67 proteins was further performed. We also explored the function of p63 in SCCHN cells by using small interfering RNA (siRNA) to silence the expression of different p63 isoforms in cell lines originating from SCCHN. The effect of p63 knockdown was studied using a Fluorescein Diacetate based cytotoxicity assay and immunohistochemistry looking at expression of differentiation markers. The response of the siRNA treated cells to radiation and cytostatic drug was also investigated. We have further studied normal oral wound healing using immunohistochemistry and quantitative PCR. By the use of a macro array comparing siRNA treated cells with non-treated cells a possible connection between the BRCA1 gene and p63 expression was shown and further studied with the use of cHIP and luciferase reporter assays. Results. The p63 isoforms are expressed in normal epithelium, with the highest levels consistently found in basal and parabasal layers. Extensive use of tobacco had no effect on p63. The quantitative PCR showed statistically increased levels of the ΔNp63 and p63isoforms. No correlation was found between p63-isoform expression patterns and proliferation. The exploration of the function of p63 in SCCHN cells by the use of small interfering RNA (siRNA) showed a statistically significant decreased survival for tumour cells when all p63 isoforms, the N-terminal truncated or the  isoforms were inhibited. No effect on cell proliferation or expression of epithelial differentiation markers was observed. We also demonstrated that inhibition of p63 expression sensitizes cells to the effects of ionizing radiation and cisplatin. The study of normal oral wound healing using immunohistochemistry and quantitative PCR showed significant changes in p63 isoform expression. The Np63 isoform was mainly expressed in the basal layer in the non proliferating and migrating cells while TAp63 was almost absent. The BRCA1 study showed p63 to bind to the BRCA1 promoter and activate the expression of BRCA1 protein. Summary. The p63 proteins have different functions and the balance between the isoforms and their localisation within the epithelium seems to be important for normal wound healing as well as cancer cell survival.
8

p63 and epithelial homeostasis : studies of p63 under normal, hyper-proliferative and malignant conditions

Gu, Xiaolian January 2010 (has links)
Background: The p63 gene is a member of the p53 transcription factor family and can produce six different proteins using two promoters and differential splicing. Expression of p63 is required for proper formation of epithelial tissues. Studies on the transcriptional control of specific genes involved in cell survival, proliferation, differentiation and adhesion have revealed the contributions of p63 to the continuously renewing stratified epithelium. In this thesis, the aim was to improve our understanding of the roles of p63 in epithelial homeostasis by investigating expression of p63 in normal and benign hyper-proliferative epithelia and exploring the influence of p63 deregulation on cancer progression. Materials and methods: Using quantitative real time RT-PCR and immunohistochemistry, we first examined the expression of different p63 isoforms in patients diagnosed with psoriasis - a benign hyper-proliferative and inflammatory skin disease. Afterwards, we investigated responses of p63 in psoriatic epidermis upon Narrowband-UVB (NB-UVB) phototherapy. At the same time, we studied the potential impact of p63 in carcinogenesis by searching for p63 transcriptional targets in a cell line derived from squamous cell carcinoma of the head and neck (SCCHN) - the sixth most common cancer worldwide with over-expression of the ∆Np63α protein as a common feature. p63 gene silencing and microarray were used to identify p63 regulated genes. Real time RT-PCR, western blot, immunohistochemistry, chromatin immunoprecipitation, transient transfection and reporter assays were performed to confirm specific genes as direct p63 targets. Results: Significant down-regulation of p63 mRNA levels was found in psoriatic lesions compared to patients’ own clinically normal skin. Moreover, a trend of decreased TAp63 mRNA levels was seen in patients’ normal skin compared to age- and sex-matched healthy controls. Following NB-UVB phototherapy, an effective first line therapy for psoriasis, expression of p63 was not significantly affected. However, significant changes in p53, FABP5, miR-21 and miR-125b were found. Surprisingly, location and expression levels of p63 proteins detected by immunohistochemistry were similar under all skin conditions. A direct transcriptional regulation of TRAF4 by p63 was seen in the SCCHN cell line and we further found that the localization of the TRAF4 protein was associated with histological differentiation of SCCHN cells. However, unlike its over-expression in SCCHN, similar TRAF4 mRNA expression levels were seen in psoriatic lesions as compared to healthy controls. Besides TRAF4, a total of 127 genes were identified as potentially p63 regulated in the SCCHN cell line and strikingly, about 20% of these genes are involved in cell adhesion or migration. Conclusions: Dysregulation of p63 isoforms in psoriatic epidermis, especially decreased TAp63 expression, and their resistance to NB-UVB phototherapy implicated a contribution of p63 to the psoriasis phenotype. Transcriptional regulation of genes involved in multiple biological pathways indicated that over-expression of p63 in SCCHN might account for altered cell differentiation, adhesion and migration, thus contributing to SCCHN. In conclusion, our studies have found additional mechanisms through which p63 guarded homeostasis of the established epithelium. Deregulation of p63 might play a role in distinct pathological conditions by participating in diverse cellular pathways under different microenvironments.
9

The p53 homolog p63 modulates acute and chronic damage in irradiated salivary glands

Mitchell, Geoffrey C January 2010 (has links)
Head and neck cancer is diagnosed in more than 50,000 Americans each year, resulting in roughly 11,000 deaths. For this disease, a typical therapeutic regimen involves cisplatin, a radiosensitizer, given alongside targeted irradiation. While technological advances such as IMRT have been useful in sparing normal tissues from radiotherapy, the salivary glands occupy much of the head and neck and surround several lymph nodes, and thus, non-diseased salivary glands are often damaged. This causes reduced salivary output, damaged oral mucosa, dysphagia, malnutrition and tooth decay. Often, these side-effects are so severe that patients discontinue treatment, however, in many cases, salivary gland damage is permanent, and treatment options are palliative. Specifically, muscarinic-cholinergic agonists are used to enhance secretion from remaining salivary cells, although due to non-specific action, these drugs have a number of ill-effects. It is clear that therapies are needed to prevent radiation-induced salivary gland damage, as well as to restore glandular function in patients who are already suffering.Previous work from our group has shown that salivary gland dysfunction results from loss of acinar cells to radiation-induced apoptosis. Importantly, a single intravenous dose of IGF1 can prevent apoptosis and preserve salivary output when given immediately prior to irradiation. Because of its broad effects, however, IGF1 may never be a viable clinical option. Instead, our goal is to identify signaling events that mediate the radioprotective effects of IGF1 downstream of Akt. Because radiation-induced apoptosis in salivary glands is p53-dependent, we assessed the contributions of the p53 homologs p63 and p73 to the DNA damage response. Here, we show that IGF1 enhances cell cycle arrest following irradiation by reducing inhibitory binding of deltaNp63 to the p21 promoter. We hypothesize that IGF1-induced cell cycle arrest may allow time for DNA repair, thus preventing apoptosis and maintaining salivary function. In addition, we indicate chronic signaling events downstream of p63 that may contribute to permanent loss of salivary function by blocking differentiation of salivary progenitor cells. Together, these results indicate that p63 may be a valid therapeutic target for both prevention of damage and restoration of function in irradiated salivary glands.
10

EXPRESSÃO de P63 e Δnp63 Como Potenciais Biomarcadores de Progressão Tumoral e Prognóstico em Carcinoma Epidermóide Oral

VALLE, I. B. 23 April 2018 (has links)
Made available in DSpace on 2018-08-01T21:35:04Z (GMT). No. of bitstreams: 1 tese_12099_Dissertação_Isabella Bittencourt da Valle.pdf: 8090609 bytes, checksum: 6e09574c3fb07de58cf9e66e8e26d822 (MD5) Previous issue date: 2018-04-23 / O prognóstico de pacientes com Carcinoma Epidermóide Oral (CEO) é majoritariamente desfavorável, principalmente devido à elevada taxa de recidiva e mortalidade. Até o momento, não existem marcadores biológicos clinicamente disponíveis que indiquem eventos de transformação tumoral ou prognóstico em CEO. Portanto, grande interesse tem sido direcionado aos genes reguladores do ciclo celular, como a participação da expressão gênica de P63 na oncogênese através da sua atividade na regulação da proliferação e diferenciação celular em CEO. Este trabalho teve como objetivo analisar a aplicabilidade de p63 como biomarcador de prognóstico e progressão tumoral. Realizou-se estudo multicêntrico internacional, no qual foram obtidas amostras biológicas, dados clínicos e seguimento clínico de 109 indivíduos com CEO provenientes do Brasil e Reino Unido. As lâminas histológicas obtidas foram avaliadas quanto à gradação tumoral, infiltrado linfocitário tumoral (TIL), padrão de invasão tumoral e invasão perineural, vascular e linfática. Tissue Microarray (TMA) foi construído considerando 3 áreas: epitélio adjacente ao tumor, displasia e tumor. Os TMAs foram submedidos à imunohistoquímica para análise de expressão de p63 e p40 (&#916;Np63) e hibridização in situ de RNA para investigar p63 mRNA. Para avaliar a expressão de p63 e p40 foi considerada a marcação nuclear em queratinócitos através de H-Score. A avaliação de p63 mRNA se deu por um guia de pontuação (score 0-4) conforme a quantidade de pontos em cada célula. O nível de significância considerado para todos os testes estatísticos foi de 95%. Teste Qui-Quadrado foi empregado para instituir associações entre as variáveis clinico-patológicas estudadas. A comparação entre a expressão da proteína p63, p40 e de p63 mRNA nas diferentes regiões foi realizada através do teste de Wilcoxon. Curvas de sobrevida global e sobrevida livre de doença foram obtidas pelo modelo de Kaplan-Meier e regressão de Cox. Nossos resultados mostraram associação entre a elevada presença de TIL no tumor com estadiamentos iniciais (p=0,001) enquanto tabagismo mostrou relação com menor TIL (p=0,044) e padrões de invasão tumoral dos tipos III e IV (p=0,032). Indivíduos etilistas/ex-etilistas apresentaram mais invasão vascular que os não etilistas (p=0,015). A expressão de p63 nos tumores foi maior que nas displasias (p=0,001) e foi associada a tumores maiores (T3 e T4) (p=0,001). Foi observada diferença quanto à expressão de p40 entre displasia e tumor (p<0,001) e displasias de alto risco apresentaram alta expressão de p40 (p=0,022). A elevada expressão de p40 tumoral mostrou associação com tumores pouco diferenciados (p=0,010) e com invasão de vasos linfáticos (p=0,022). Não foi observada diferença de expressão de p63 mRNA entre as regiões estudadas. Indivíduos com estadios iniciais (p=0,001) e não tabagistas (p=0,035) tiveram maior sobrevida global. Mostraram pior sobrevida livre de doença indivíduos cujos padrões de invasão tumoral eram III e IV (p=0,014) e que apresentavam tumores maiores (p=0,004). Concluímos com este estudo que a expressão de p63, de p40, são úteis como marcadores de progressão tumoral, mas não comportam-se como bons marcadores de prognóstico uma vez que não mostraram influenciar os índices de sobrevida global e sobrevida livre de doença.

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