京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第18178号 / 医博第3898号 / 新制||医||1004(附属図書館) / 31036 / 京都大学大学院医学研究科医学専攻 / (主査)教授 宮地 良樹, 教授 羽賀 博典, 教授 山下 潤 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DGAM

O nervo vago (X nervo craniano) está formado por fibras motoras somáticas e viscerais e por fibras sensitivas e possui um trajeto e distribuição mais extensos do que qualquer outro nervo craniano. Nos seres humanos, o nervo vago tem sua origem craniana pelo forame jugular e possui dois gânglios no seu trajeto: o gânglio superior e o gânglio inferior. Em ratos, o nervo vago emerge pelo forame lacerado posterior, apresenta o gânglio nodoso e se estende posteriormente, em frente a coluna vertebral, por todo o pescoço, tórax até o abdome. Na literatura são escassos informações sobre as diferenças morfometricas e morfológicas dos nervos vagos em ratos normotensos (WKY) e ratos espontaneamente hipertensos (SHR). O objetivo do presente estudo foi comparar os aspectos morfológicos e morfométricos dos diferentes segmentos e lados do nervo vago de ratos das linhagens WKY e SHR, machos e fêmeas. Os animais (n =4 em cada grupo) foram pesados, anestesiados e sua pressão arterial aferida. Após o preparo com técnicas histológicas convencionais, secções transversais dos segmentos proximal e distal foram obtidas para análise de microscopia de luz e através de um sistema de imagem computacional. O peso corporal dos animais mais velhos acompanhou o crescimento, sendo maior nos machos do que nas fêmeas. Não foram observadas diferenças estatísticas na morfologia e morfometria entre os lados e segmentos tanto em fêmeas como machos. Quando comparados os animais entre as idades foi possível gerar alterações na área fascicular, número de fibras, diâmetro mínimo da fibra, área da bainha, área da fibra e diâmetro do axônio. / The vagus nerve (X cranial nerve) is formed by somatic and visceral motor fibers and by sensory fibers and has a more extensive path and distribution than any other cranial nerve. In humans, the vagus nerve has its cranial origin through the jugular foramen and has two ganglia in its path: the superior ganglion and the inferior ganglion. In rats, the vagus nerve emerges through the posterior lacerated foramen, presents the nodous ganglion and extends posteriorly, in front of the vertebral column, throughout the neck, thorax to the abdomen. In the literature, there is scarce information about the morphometric and morphological differences of the vagus nerves in normotensive rats (WKY) and spontaneously hypertensive rats (SHR). The objective of the present study was to compare the morphological and morphometric aspects of the different segments and sides of the vagus nerve of rats of WKY and SHR, both male and female. The animals (n = 4 in each group) were weighed, anesthetized and their blood pressure measured. After preparation with conventional histological techniques, cross sections of the proximal and distal segments were obtained for light microscopy analysis and through a computer imaging system. The body weight of the older animals followed the growth, being higher in the males than in the females. No statistical differences were observed in morphology and morphometry between the sides and segments in both females and males. When comparing the animals between the ages it was possible to generate changes in the fascicular area, number of fibers, minimum diameter of the fiber, area of the sheath, area of the fiber and diameter of the axon.

A resposta inflamatória está envolvida em muitos aspectos da biologia do câncer. O inflamassoma é um complexo multiprotéico intracelular compostos por três elementos: um receptor de reconhecimento de padrões moleculares (PRR), uma proteína ligadora ASC (proteína speck-like associada à apoptose com domínio de recrutamento de caspase) e o zimogênio pró-caspase-1. A ativação da caspase-1 é responsável pela síntese de IL-18 e, principalmente, de IL-1?. A ativação da caspase-1 é ainda capaz de induzir a piroptose, um tipo de morte celular inflamatória. O papel dos inflamassomas no câncer ainda é mal definido, devido às suas funções contrastantes na oncogênese, variando a depender do tipo de tecido e do estágio da tumorigênese em que são ativados. Estudos recentes mostraram uma ativação do inflamassoma à medida que o melanoma progride. Avaliamos a expressão de componentes do inflamassoma, incluindo dois tipos de PRR (NLRP1 e NLRP3), da enzima caspase-1, e da IL-1beta em neoplasias melanocíticas benignas e malignas, por meio de técnica de imunohistoquímica. Foram analisadas amostras de tecidos embebidos em parafina de 25 pacientes com melanoma (16 melanomas finos e 9 melanomas intermediários-espessos) e 22 pacientes com nevo melanocítico (12 nevos intradérmicos e 10 nevos displásicos). Todas as amostras de pele foram recuperadas dos arquivos do Departamento de Dermatologia do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo. Evidenciamos uma maior expressão de NLRP1, NLRP3 e caspase-1 nos melanomas quando comparados aos nevos. Não houve diferença estatisticamente significativa quanto a expressão de IL-1beta entre os grupos. De forma inesperada, a descoberta mais interessante foi uma maior expressão de NLRP1 em melanomas finos do que nos tumores mais espessos. Esses achados sugerem que um aumento de NLRP1 poderia representar um evento promotor na transformação de melanócitos, mas que não estaria envolvido na progressão tumoral. Estudos adicionais são necessários para esclarecer esta complexa relação entre as proliferações melanocíticas e o inflamassoma / Inflammatory response is involved in many aspects of cancer biology. Inflammasomes are a group of cytosolic multiprotein complexes, classically consisting of an upstream sensor protein of the NOD-like receptor (NLR) family, the adaptor protein ASC, and the downstream effector caspase-1. Its activation leads to the production of biologically active IL-1beta and IL-18, and consequently contributing to the inflammatory process. Caspase-1 activation can also induce pyroptotic cell death, that is accompanied by the release of cytosolic contents to the extracellular space eliciting local inflammation. The roles of the inflammasomes in cancer are still ill defined, due to their contrasting roles in oncogenesis. Recent studies have shown an activation of the inflammosome as melanoma progresses. We evaluated the expression of inflamassome components (NLRP1, NLRP3, caspase-1) and of IL-1beta in melanocytic neoplasms, by immunohistochemistry. Formalin-fixed, paraffin-embedded tissue samples from 25 patients with melanoma (16 thin melanomas and 9 intermediate-thick melanomas), and 22 patients with melanocytic nevus (12 intradermal nevi and 10 dysplastic nevi) were analyzed. All skin samples were retrieved from the files of the Department of Dermatology at Clinics Hospital of Faculty of Medicine, University of São Paulo. Comparing all nevi with all melanomas, we found a higher expression of NLRP1, NLRP3 and caspase-1 in melanomas. There was no difference of IL-1beta expression between the groups. For the first time, to our knowledge, we reported an increasing expression of NLRP1 in melanoma compared to melanocytic nevus. Unexpectantly, NLRP1 expression resulted augmented NLRP1 in thin melanomas compared with intermediate-thick melanomas. These data may suggest a role of NLRP1 in oncogenesis, but that its expression decreases as disease progresses. We can hypothesize that an increase of NLRP1 could represent a promoter event in melanocyte transformation, but it does not be involved in tumour progression. The association between nevus, melanoma and inflammasomes seems to be complex and further studies are necessary to clarify this

Les mélanocytes sont des cellules productrices de mélanines, à l’origine de la teinte de la peau, des yeux et des cheveux. Elles dérivent d'une population multipotente appelée cellules de la crête neurale, qui génère entre autres également tout le système nerveux périphérique. Une prolifération accrue des précurseurs des mélanocytes durant le développement entraine chez l’homme l’apparition d’un nævus mélanocytaire congénital (NMC). Cette prolifération est due à une mutation somatique au sein d'un de ces précurseurs, dans des gènes de la voie de signalisation des MAP-Kinases, NRAS ou BRAF. Les plus grandes formes, couvrant des parties entières du corps, sont syndromiques. Ils peuvent associer des mélanocytoses, des malformations ou tumeurs cérébrales ou méningées, parfois épileptogènes, ainsi qu'un risque autour de 5% de dégénérer en mélanome, dans un des sites atteints. Durant ma thèse j’ai exploré des modèles murins où les protéines NRAS ou BRAF constitutivement actives sont exprimées très tôt au cours de l’embryogenèse, dans les cellules de la crête neurale. Les embryons mutants BrafV600E connaissent une létalité embryonnaire, probablement due à une superposition de défauts vasculaires et cérébraux. En revanche, les souris NrasG12D sont viables,présentent des mélanocytoses extracutanées dans des sites divers, ainsi qu’une hyperpigmentation cutanée, visible en postnatal. Cette hyperpigmentation est associée à une augmentation de la densité folliculaire, ainsi qu’à un dérèglement du cycle du follicule pileux. Des cultures de cellules de crête neurale murines, BrafV600E ou NrasG12D et contrôles, ont permis d’élucider sur le plan moléculaire les effets de telles mutations. / Melanocytes are the vertebrate cells that produce melanin, conferring color on skin, hair and eyes. They arise from a multipotent embryonic cell population called the neural crest, which also gives rise to the peripheral nervous system of the body and many other cell types. Abnormal proliferation of melanocyte precursors before birth can lead to human congenital melanocytic nevus (CMN). CMN are caused by prenatal somatic mutations in the NRAS or BRAF genes of the MAP-Kinase pathway, in one of these precursors. The largest CMN, covering entire segments of the body or head, are syndromic. They are sometimes associated with epileptogenic brain or meningeal malformations, tumors or melanocytosis, and they present a risk of about 5% in all these sites of becoming pediatric malignant melanoma. During my thesis, I explored mouse models expressing constitutively activated NRAS or BRAF proteins in neural crest cell lineages, from very early in embryogenesis. BrafV600E mutant embryos are embryonic lethal at mid-gestation, probably due to coinciding vascular and brain defects. In contrast, NrasG12D mice are viable, present extracutaneous melanocytosis in various sites as well as postnatal hyperpigmentation of the skin. This is associated with increased hair follicle density, and a deregulated hair cycle. Cell culture of mutant or wildtype mouse neural crest cells of both genotypes has permitted the comparison and discovery of molecular differences introduced by these mutations.

A resposta inflamatória está envolvida em muitos aspectos da biologia do câncer. O inflamassoma é um complexo multiprotéico intracelular compostos por três elementos: um receptor de reconhecimento de padrões moleculares (PRR), uma proteína ligadora ASC (proteína speck-like associada à apoptose com domínio de recrutamento de caspase) e o zimogênio pró-caspase-1. A ativação da caspase-1 é responsável pela síntese de IL-18 e, principalmente, de IL-1?. A ativação da caspase-1 é ainda capaz de induzir a piroptose, um tipo de morte celular inflamatória. O papel dos inflamassomas no câncer ainda é mal definido, devido às suas funções contrastantes na oncogênese, variando a depender do tipo de tecido e do estágio da tumorigênese em que são ativados. Estudos recentes mostraram uma ativação do inflamassoma à medida que o melanoma progride. Avaliamos a expressão de componentes do inflamassoma, incluindo dois tipos de PRR (NLRP1 e NLRP3), da enzima caspase-1, e da IL-1beta em neoplasias melanocíticas benignas e malignas, por meio de técnica de imunohistoquímica. Foram analisadas amostras de tecidos embebidos em parafina de 25 pacientes com melanoma (16 melanomas finos e 9 melanomas intermediários-espessos) e 22 pacientes com nevo melanocítico (12 nevos intradérmicos e 10 nevos displásicos). Todas as amostras de pele foram recuperadas dos arquivos do Departamento de Dermatologia do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo. Evidenciamos uma maior expressão de NLRP1, NLRP3 e caspase-1 nos melanomas quando comparados aos nevos. Não houve diferença estatisticamente significativa quanto a expressão de IL-1beta entre os grupos. De forma inesperada, a descoberta mais interessante foi uma maior expressão de NLRP1 em melanomas finos do que nos tumores mais espessos. Esses achados sugerem que um aumento de NLRP1 poderia representar um evento promotor na transformação de melanócitos, mas que não estaria envolvido na progressão tumoral. Estudos adicionais são necessários para esclarecer esta complexa relação entre as proliferações melanocíticas e o inflamassoma / Inflammatory response is involved in many aspects of cancer biology. Inflammasomes are a group of cytosolic multiprotein complexes, classically consisting of an upstream sensor protein of the NOD-like receptor (NLR) family, the adaptor protein ASC, and the downstream effector caspase-1. Its activation leads to the production of biologically active IL-1beta and IL-18, and consequently contributing to the inflammatory process. Caspase-1 activation can also induce pyroptotic cell death, that is accompanied by the release of cytosolic contents to the extracellular space eliciting local inflammation. The roles of the inflammasomes in cancer are still ill defined, due to their contrasting roles in oncogenesis. Recent studies have shown an activation of the inflammosome as melanoma progresses. We evaluated the expression of inflamassome components (NLRP1, NLRP3, caspase-1) and of IL-1beta in melanocytic neoplasms, by immunohistochemistry. Formalin-fixed, paraffin-embedded tissue samples from 25 patients with melanoma (16 thin melanomas and 9 intermediate-thick melanomas), and 22 patients with melanocytic nevus (12 intradermal nevi and 10 dysplastic nevi) were analyzed. All skin samples were retrieved from the files of the Department of Dermatology at Clinics Hospital of Faculty of Medicine, University of São Paulo. Comparing all nevi with all melanomas, we found a higher expression of NLRP1, NLRP3 and caspase-1 in melanomas. There was no difference of IL-1beta expression between the groups. For the first time, to our knowledge, we reported an increasing expression of NLRP1 in melanoma compared to melanocytic nevus. Unexpectantly, NLRP1 expression resulted augmented NLRP1 in thin melanomas compared with intermediate-thick melanomas. These data may suggest a role of NLRP1 in oncogenesis, but that its expression decreases as disease progresses. We can hypothesize that an increase of NLRP1 could represent a promoter event in melanocyte transformation, but it does not be involved in tumour progression. The association between nevus, melanoma and inflammasomes seems to be complex and further studies are necessary to clarify this

Orientador: Elemir Macedo de Souza / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-11T18:27:24Z (GMT). No. of bitstreams: 1 Vallarelli_AndrelouFraleteAyres_D.pdf: 1630938 bytes, checksum: 23e0249f3f941326829a686dce25ca9e (MD5) Previous issue date: 2008 / Resumo: O objetivo deste estudo foi verificar o desenvolvimento de nevos melanocíticos (NM) e a ocorrência de efélides, importantes fatores de risco para melanoma cutâneo, nos alunos de uma escola particular composta majoritariamente por descendentes de holandeses na cidade de Holambra - SP, Brasil e fornecer informações sobre a influência do meio ambiente nestes indivíduos que mantiveram características fenotípicas semelhantes às de seus antepassados e que não se dispersaram, permanecendo unidos em comunidades isoladas. Em 1999, o autor iniciou estudo coorte para contagem de NM nos 282 alunos (53.9% meninos) com idades entre 3 e 17 anos. Cinco anos mais tarde, o mesmo autor realizou novo exame envolvendo 148 (52.43% de resposta) alunos, 73 (49.32%) meninos e 75 (50.67%) meninas com idades entre 8 e 22 anos, entre 2006 e 2007. Verificou-se os dados sócio-demográficos e físicos e as manifestações dermatológicas. Analisou-se a alteração das manifestações aferidas no exame dermatológico e a relação das variáveis principais (idade, sexo, fototipo, cor dos olhos, cor dos cabelos, uso de proteção solar, etnia dos alunos e dos pais) com a presença de NM e efélides no início e no final do estudo. Verificou-se que foi significativo o aumento no número de NM tanto nas áreas cobertas quanto nas áreas expostas dos alunos no final do estudo. O estudo revelou ainda que os meninos tiveram maior número total de NM (tanto nas áreas cobertas quanto nas áreas expostas) que as meninas e que houve aumento significativo na ocorrência de nevos displásticos (ND) no seguimento. Foi significativo o aumento na ocorrência de efélides nos alunos de etnia holandesa com pele, cabelos e olhos claros e que não utilizaram proteção solar. O resultado da análise de probabilidade com nível de significância 5% e intervalo de 95% de confiança para a razão de risco revelou que os meninos têm mais chance de desenvolver NM (tanto nas áreas cobertas quanto nas áreas expostas) que as meninas e que os alunos de etnia não miscigenada e miscigenada e com cabelos claros têm respectivamente mais chance de desenvolver NM que os alunos de outras etnias e com cabelos escuros. A análise revelou ainda que os alunos com fototipo I são mais propensos a desenvolver NM nas áreas cobertas que os alunos do fototipo II e III. A ocorrência de efélides foi maior nos alunos do fototipo I, com ascendência paterna e materna holandesa e com cabelos claros. Este pode ser considerado o primeiro estudo prospectivo realizado no Brasil para verificar o desenvolvimento de NM e os dados obtidos neste estudo contribuíram para demonstrar que os alunos que mantiveram as características fenotípicas de seus antepassados têm maior probabilidade de desenvolver NM e efélides que os alunos pertencente aos outros grupos étnicos. / Abstract: The objective of this study was to verify the development of melanocytic nevi (MN) and ephelides, important risk factors for cutaneous melanoma, in students of a private school who were mostly Dutch and Dutch descendants in Holambra, Brazil and to obtain information about the effects of environmental factors on these individuals who maintained phenotypical characteristics similar to those of their ancestors. In 1999, the author began a cohort study to count NM in 282 students (53.9% boys) aged between 3 and 17 years. Five years later, the study follow-up was carried out by the same author involving 148 (52.43% response) students, 73 (49.32%) boys and 75 (50.67%) girls aged between 8 and 22 years, from 2006 to 2007. The social-demographic and physical characteristics, as well as the cutaneous manifestations were verified. Cutaneous manifestations alterations and the relationship of these main variables (age, sex, skin phototype, eye color, hair color, photoprotection mechanisms and ethnic group) with the presence of MN and ephelides at the beginning and at the end of study were verified. The increase in number of MN, both in covered areas and exposed areas was significant at the end of study. The study also revealed that the boys had a higher total number of MN, both in covered areas and exposed areas, than the girls and there was significant increase of dysplastic nevi (DN) at the end of study. The increase of occurrence of ephelides in students from the non-mixed group, with skin phototype I, with light-colored hair and eyes and in those who never used protection was significant. The result of probability analysis with a 5 % significance level and 95% confidence interval for the odds ratio revealed that the boys have greater probability of developing nevi in covered and exposed areas than the girls, and that the non-mixed and mixed ethnic groups with light-colored hair had respectively greater probability of developing MN than the students from other ethnic groups and those with dark-colored hair. The analysis also revealed that the students with skin phototype I had greater probability of developing MN in the covered areas than the students with skin phototype II and III. The occurrence of ephelides was greater in the students with skin phototype I, with paternal and maternal Dutch ascendants and with light-colored hair. This study may be considered the first prospective study carried out in Brazil to verify the development of MN. The data obtained in this study contributed to demonstrate that the students that retain the phenotypical characteristics of their ancestors have greater probability of developing MN and ephelides than the other ethnic groups. / Doutorado / Clinica Medica / Doutor em Ciências Médicas

Epidermal nevus syndromes encompass a highly heterogeneous group of systemic disorders, characterized by epidermal nevi, and a spectrum of neuromuscular, ocular, and bone abnormalities. Cutaneous-skeletal hypophosphatemia syndrome (CSHS) constitutes a specific sub-entity in which elevated levels of fibroblast growth factor-23 cause hypophosphatemic rickets that are, to date, not amenable to causal therapy. Here, we report the first long-term follow-up of causal treatment with burosumab in a 3-year-old female patient with CSHS. 4 weeks after initiation of burosumab treatment, serum phosphate normalized to age-appropriate levels. Furthermore, long-term follow-up of 42 months revealed significant improvement of linear growth and gross physical functions, including respiratory insufficiency. Radiographic rickets severity as well as subjective bone pain were strongly reduced, and no side effects were observed over the course of treatment. In summary, we, here, report about a successful treatment of hypophosphatemic rickets in CSHS with burosumab over the time course of 42 months. In our patient, burosumab showed convincing efficacy and safety profile, without any loss of effect or increase of dose.

Melanocytic neoplasms have been genetically characterized in detail during the last decade. Recurrent CTNNB1 exon 3 mutations have been recognized in the distinct group of melanocytic tumors showing deep penetrating nevus-like morphology. In addition, they have been identified in 1–2% of advanced melanoma. Performing a detailed genetic analysis of difficult-to-classify nevi and melanomas with CTNNB1 mutations, we found that benign tumors (nevi) show characteristic morphological, genetic and epigenetic traits, which distinguish them from other nevi and melanoma. Malignant CTNNB1-mutant tumors (melanomas) demonstrated a different genetic profile, instead grouping clearly with other non-CTNNB1 melanomas in methylation assays. To further evaluate the role of CTNNB1 mutations in melanoma, we assessed a large cohort of clinically sequenced melanomas, identifying 38 tumors with CTNNB1 exon 3 mutations, including recurrent S45 (n = 13, 34%), G34 (n = 5, 13%), and S27 (n = 5, 13%) mutations. Locations and histological subtype of CTNNB1-mutated melanoma varied; none were reported as showing deep penetrating nevus-like morphology. The most frequent concurrent activating mutations were BRAF V600 (n = 21, 55%) and NRAS Q61 (n = 13, 34%). In our cohort, four of seven (58%) and one of nine (11%) patients treated with targeted therapy (BRAF and MEK Inhibitors) or immune-checkpoint therapy, respectively, showed disease control (partial response or stable disease). In summary, CTNNB1 mutations are associated with a unique melanocytic tumor type in benign tumors (nevi), which can be applied in a diagnostic setting. In advanced disease, no clear characteristics distinguishing CTNNB1-mutant from other melanomas were observed; however, studies of larger, optimally prospective, cohorts are warranted.

<p>Uvod: Od kada je prvi put opisan pre 30 godina, kod porodica obolelih od melanoma<br />kože, displastični nevus je predmet debate. Klinički najznačajnija kontroverza je da se<br />displastični nevus klinički često smatra sumnjivim i da se te&scaron;ko razlikuje od ranog<br />melnoma kože. Ovakav klinički izgled displastičnog nevusa je razlog čestih nepotrebnih<br />ekscizija, jednog od najče&scaron;ćih nevusa čoveka. Ciljevi: Ispitati kliničke i dermoskopske karakteristike patohistolo&scaron;ki potvrđenih displastičnih nevusa, i utvrditi učestalost displastičnih nevusa među sumnjivim melanocitnim lezijama koje su odabrane kliničko-dermoskopskim pregledom. Metode: U analitičkoj kliničkoj studiji, u prospektivnom delu, koristili smo kliničko-dermoskospki pristup po predloženom protokolu za selekciju sumnjivih melanocitnih lezija za eksciziju. Ekscidirano je 279 lezija. Od ukunog broja, 83 su bile lezije veoma sumnive na melanom kože, kod 116 lezija melanom nije mogao biti isključen u diferencijalnoj dijagnozi, a 80 lezija su imponovale dobroćudne i ekscidirane su zbog smetnji koje su pričinjavale pacijentu. Klinički su lezije opisivane prema ABCD akronimu (A za asimetriju, B za nepravilnost ivica, C za nepravilnu prebojenost i D za veličinu preko 5 mm). Za dermoskopski opis lezija su korisćeni algoritmi Analiza struktura i Lista od sedam tačaka. Rezultati: Nakon histopatolo&scaron;kog pregleda ekscidiranih 279 lezija, 242 lezije su bile nevusi, od kojih 131 displastični nevus, koji je analiziran posebno za potrebe ove studije, dok su 47 lezija činili melanomi kože. Histopatolo&scaron;ki potvrđeni displastični nevusi su proistekli dominantno iz grupa lezija kliničko-dermoskospki upućenih kao sumnjive na melanom ili iz grupe gde melanom nije mogao biti isključen u diferencijalnoj dijagnozi OR 2,49 (95%CI 1,51-4,11) p=0,0003. Svako ispitano kliničko obeležje ponaosob i u svim mogućim kombinacijama, je bilo od značaja samo za melanoma kože p&lt;0,0001. Nije bilo značajnih razlika u grupi displastičnih nevusa i ostalih nevusa. Displastične nevuse su činile sumnivim njihove dermoskopske karakteristike. Kod ovih nevusa je bila če&scaron;ća multikomponentna struktura OR 4,84 (95%CI 2,87-8,16) p&lt;0,0001 i nepravilne globule OR 7,32 (95%CI 3,35-15,99) p&lt;0,0001. Nepravilne mrlje su uočene kod 90/96 displastičnih nevusa i kod 41/47 melanoma bez značajne razlike. Zaključak: Klinički displastični nevusi nisu imali kliničke karakteristike koje se obično koriste za njihov opis, te klinički nisu imali znake sumnjivih lezija. Klinički su izgledali poput banalnih nevusa. Kombinovani kliničko-dermoskospki pristup za odabir sumnjivih lezija je ukazao na značaj nekih dermoskospkih obeležja. Multikomponentna struktura i nepravilne globule su se vi&scaron;e javljale kod displastičnih nevusa. Poseban je značaj nepravilnih mrlja koje su podjednako često bile uočavane i kod displastičnih nevusa i tankih melanoma.</p> / <p>Background: Dysplastic nevus, a benign melanocytic lesion has been a matter of debate over the last thirty years, since its first description in families with melanoma. The most important controversy is that dysplastic nevus is usually considered to be suspicious, not easily distinguishable from early melanoma by its clinical appearance. This is followed by numerous unnecessary excisions of a nevus that is considered to be one of the most common in humans. Objectives: To describe the clinical and dermoscopic characteristics of dysplastic nevus, and&nbsp; to&nbsp; investigate&nbsp; its&nbsp; proportion&nbsp; in&nbsp; suspicious&nbsp; melanocytic&nbsp; lesions&nbsp; using clinicodermoscopic approach. Methods: In an analytical clinical study, in the prospective part of the study, we used a combined&nbsp; clinicodermoscopic&nbsp; approach&nbsp; according&nbsp; to&nbsp; a&nbsp; proposed&nbsp; protocol,&nbsp; to&nbsp; select lesions for excision. A total of 279 lesions were excised. Of the total number, 83 were very suspicious for melanoma, 116 where melanoma could not be excluded, and eighty were considered to be benign. Still they were excised because they were a burden for patients. Clinical appearance was studied using ABCD acronym (A for assimetry, B for border&nbsp; irregularity,&nbsp; C&nbsp; for&nbsp; color&nbsp; variegation,&nbsp; and&nbsp; D&nbsp; for diameter&nbsp; of&nbsp; more&nbsp; than&nbsp; 5mm). Dermoscopic&nbsp; description&nbsp; of&nbsp; lesions&nbsp; was&nbsp; performed&nbsp; according&nbsp; to&nbsp; algorithms Pattern Analysis and Seven-point Checklist. Results:&nbsp; After&nbsp; histopathological&nbsp; analysis&nbsp; of&nbsp; the&nbsp; 279&nbsp; lesions,&nbsp; 242&nbsp; lesions&nbsp; were&nbsp; nevi, among them 131 dysplastic nevi that were analyzed separately for the purpose of this study and 47 lesions were skin melanoma. Histopathologicaly proven dysplastic nevus originated mainly from a group of lesions clinicodermoscopily recognized as suspicious of melanoma, or a group where melanoma could not be excluded OR 2.49 (95%CI 1.51-4.11) p=0.0003. Each examined clinical feature alone or in any possible combination of features&nbsp; was&nbsp; important&nbsp; only&nbsp; for&nbsp; melanoma&nbsp; p&lt;0.0001.&nbsp; There&nbsp; were&nbsp; no&nbsp; significant differences between dysplastic nevus group and a group of nevi. Dermoscopic features were more important for the overall suspicious&nbsp; appearance. Multicomponent structure OR&nbsp; 4.84&nbsp; (95%CI&nbsp; 2.87-8,16)&nbsp; p&lt;0.0001&nbsp; and&nbsp; irregular&nbsp; globules&nbsp; OR&nbsp; 7.32&nbsp; (95%CI&nbsp; 3.35-15.99)&nbsp; p&lt;0.0001&nbsp; were&nbsp; frequent.&nbsp; Irregular&nbsp; blotches&nbsp; were&nbsp; found&nbsp; in&nbsp; 90/96&nbsp; and 41/47, dysplastic nevus and melanoma respectively, without significant differences. Conclusion:&nbsp; Clinically&nbsp; dysplastic&nbsp; nevi&nbsp; did&nbsp; not&nbsp; show&nbsp; clinical&nbsp; characteristics&nbsp; that&nbsp; were usually used to describe them, and did not show signs of suspicious lesions. Clinically, they looked more like banal nevi. The commbined clinicodermoscopic approach to select suspicious melanocytic lesions, revealed some dermoscopic features that were often seen in dysplastic nevi, like the multicomponent structure and the irregular globules, while the irregular blotches were a feature shared both by dysplastic nevi and melanoma.</p>

Incidência de melanoma cutâneo maligno (MM) está aumentando em torno de 2,5 a 4% por ano no mundo. Os principais fatores de risco são história familiar de MM, múltiplos nevos benignos ou atípicos, e fatores adicionais como a imunossupressão, sensibilidade solar e exposição à radiação ultravioleta (UV). A instabilidade genômica é responsável pelo acúmulo de mutações que frequentemente estão envolvidas na transformação maligna. Podemos estudar a instabilidade genômica através de duas formas: microssatélites e RAPD (Random Amplified Polymorphic DNA). Na instabilidade genética o DNA repetitivo pode sofrer alterações. Através da Instabilidade de microssatélites (MSI) e da perda da heterozigosidade (LOH) podemos diferenciar tecidos normais de tumorais. A técnica de RAPD (baseada na PCR) produz fingerprints utilizados para detectar instabilidade genômica, polimorfismos, mutações e translocações quando comparados à fingerprints de amostras normais. No estudo de nove microssatélites encontramos um aumento de MSI (p=0.0132). D9S50 apresentou o maior número de alterações (28,5%) em nevos e MMs. D6S252, D9S52 e D9S180 são candidatos à marcador de prognóstico de MM porque apresentaram alterações (MSI + LOH) apenas em MMs. Na análise de 15 primers de RAPD em 12 amostras de MMs obtivemos 100 % de alteração com relação ao número ou posição das bandas. Os primers OPA-2 e OPA-14 são capazes de detectar alterações genéticas nos MMs. Dos padrões obtidos foram encontradas bandas que estavam ausentes nos tumores e estas foram clonadas e seqüenciadas. Estes procedimentos evidenciaram alterações em 9q33 e 12q15. O RAPD propicia o estudo do genoma humano sem a definição prévia de um lócus. Assim, podemos detectar alterações até então desconhecidas aumentando o conhecimento sobre a genômica tumoral. / The incidence of malignant skin melanoma (MM) increases around 2,5 a 4% each year in the world. The main risk factors are family history of MM, multiple benign or atypical nevi, and additional factors such as immunossuppression, sun sensibility and UV exposure. Genomic instability is responsible for a collection of mutations that are frequently involved in malignant transformation, and it can cause alterations in repetitive DNA sequences. There are two ways of studying genomic instability: microsatellites and RAPD (Random Amplified Polymorphic DNA). Through microsatellite instability (MSI) and loss of heterozygosis (LOH) we can separate normal from tumoral tissues. RAPD technique (which is based on PCR) generates fingerprints used for detection of genomic instability, polymorphisms, mutations and translocations that can be compared with fingerprint generated from normal tissue. Studying nine microsatellite, we found an increased MSI (p=0.0132). D9S50 showed the greater number of alterations (28,5%) in nevi and MM. D6S252, D9S52 e D9S180 are candidates for MM prognostic marker for showing alterations (MSI+LOH) in melanomas only. The analysis of 15 RAPD primers in 12 MM samples showed 100% of alteration related to the number or location of the bands. OPA-2 and OPA-14 primers are capable of detecting genetic alterations in MM. In the patterns obtained, two bands which were absent in tumors were found, and they were cloned and submitted to sequencing. These procedures highlighted alterations in loci 9q33 e 12q15. RAPD makes it possible to study the genome without a previous definition of a locus. So we are able to detect alterations so far unknown, increasing our knowledge on tumor genetics.