Made available in DSpace on 2017-07-10T14:57:30Z (GMT). No. of bitstreams: 1 Dissertacao_Renata Zoraida_ Rizental Delgado.pdf: 2641394 bytes, checksum: c9a23494ed97bde58dcc144b147a740f (MD5) Previous issue date: 2015-02-20 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Introduction: Gorlin syndrome (GS) also known as Nevoid Basal Cell Carcinoma Syndrome, is a rare disease resulting from mutations in Patched-1 gene and characterized by triad of disorders comprising multiple basal cell carcinomas, numerous keratocystic odontogenic tumors (KOT) and skeletal abnormalities. About 90% of patients develop KOTs in gnathic bones, preferably in the posterior mandible, presenting radiographically as radiolucent lesions uni- or multilocular. Studies suggests that KOTs associated with GS (KOTGSs) have distinct and more aggressive behavior compared to those who developing sporadically (KOTSPs). Objectives: This study aimed at comparing clinical, histopathological and immunohistochemical features of KOTSPs and KOTGSs from different institutions in Brazil and abroad, and understand the role of proteins associated with proliferation/cell cycle (p53, p63 and Ki-67), the alpha-smooth muscle actin (α-SMA) and syndecan-1 (CD138) in an attempt to associate the expression with biological behavior of KOTs. Methodology: Were previously reviewed and selected 30 KOTGSs and 8 KOTSPs, in which were performed qualitative and semi-quantitative analysis histopathological and immunohistochemical to p53, p63, Ki-67, SMA and CD138. Results: 30 cases of KOTGSs were obtained from 12 patients with GS, 5 females (41.66%) and 7 men (58.33%); whereas in group of KOTSPs, 5 cases (62.50%) was in females and 3 males (37.50%). About 58.33% of patients with GS had more than one lesion throughout life. The average age of individuals with GS was 14.66 ± 16.81 years, while in patients with KOTSPs was 41 ± 39.59. The predominant radiographic pattern was radiolucent unilocular, preferably affecting the posterior mandible. Histopathological features in both groups was analyzed, and the most frequent was pleomorphism in KOTGSs. In addition, there was increased expression of p53 and p63 in KOTGSs and similar expression of SMA and Ki-67 between groups. It was also observed that there was a lower reactivity for CD138 in the basal epithelial layer of KOTGSs and stromal expression of CD138 was similar between the groups. Conclusions: Agressiveness of KOTGSs can be explained by increased cellular pleomorphism rate and expression of p53 and p63 and tendency to loss of syndecan-1 expression compared to KOTSPs. / Introdução: A Síndrome de Gorlin (SG) também conhecida como Síndrome do Carcinoma Nevóide Basocelular, é uma doença rara resultante de mutações no gene Patched-1 e caracterizada por uma tríade de alterações que inclui múltiplos carcinomas basocelulares, numerosos tumores odontogênicos queratocísticos (TOQs) e anormalidades esqueléticas. Cerca de 90% dos portadores desenvolvem TOQs no interior dos ossos gnáticos, preferencialmente na região posterior da mandíbula, apresentando-se radiograficamente como lesões radiolúcidas uni ou multiloculares. Estudos têm sugerido que os TOQs associados à SG (TOQSG) apresentam comportamento distinto e mais agressivo em comparação àqueles que desenvolvem-se de modo esporádico (TOQEs). Objetivos: O presente estudo teve como objetivo analisar comparativamente os aspectos clínicos, histopatológicos e imuno-histoquímicos de TOQEs e TOQSGs oriundos de diferentes instituições do Brasil e do exterior, além de entender o papel de proteínas associadas com proliferação/ciclo celular (p53, p63 e Ki-67), da actina de músculo liso-alfa (α-SMA) e da proteína sindecano-1 (CD138), na tentativa de associar a expressão das mesmas com o comportamento biológico dos TOQs. Metodologia: Foram previamente revisados e selecionados 30 TOQSGs e 8 TOQEs, nos quais foram realizadas análises qualitativas e semi-quantitativas histopatológicas e imuno-histoquímicas para p53, p63, Ki-67, AML e CD138. Resultados: Trinta casos de TOQSGs foram obtidos de 12 pacientes com SG, 5 do gênero feminino (41,66%) e 7 do gênero masculino (58,33%); ao passo que no grupo dos TOQEs, 5 casos (62,50%) acometeram o gênero feminino e 3 o masculino (37,50%). Cerca de 58,33% dos pacientes com SG apresentaram mais de uma lesão ao longo da vida. A média de idade dos indivíduos com SG foi de 16,81 anos ± 14,66 enquanto dos portadores de TOEs foi de 41 anos ± 39,59. O padrão radiográfico predominante foi o radiolúcido unilocular, afetando preferencialmente a região posterior de mandíbula. Foram avaliadas as características histopatológicas de ambos os grupos de lesões, sendo o pleomorismo celular mais frequente nos TOQSGs. Além disso, observou-se maior expressão de p53 e p63 nos TOQSG e expressão similar de AML e Ki-67 entre os grupos. Observou-se ainda que houve menor reatividade para CD138 no estrato epitelial basal dos TOQSGs e a expressão estromal de CD138 foi similar entre os grupos analisados. Conclusões: A maior agressividade dos TOQSGs pode ser explicada pela maior taxa de pleomorfismo celular, maior expressão de p53 e p63 e tendência à perda de expressão de sindecano-1 quando comparados aos TOQEs.

Introdução. O Tumor Odontogênico Queratocístico (TOQC) é uma lesão de origem odontogênica que se apresenta exclusivamente nos ossos gnáticos e possui alto potencial de agressividade local. Pode estar associado à Síndrome do Carcinoma Nevóide Basocelular (SCNBC), que se caracteriza por apresentar inúmeras alterações de desenvolvimento, múltiplos carcinomas basocelulares (CBCs) além de anormalidades esqueléticas. Cerca de 65 a 100% dos pacientes com a síndrome podem apresentar múltiplos TOQCs. Objetivo. Avaliar e correlacionar os achados clínicos, histopatológico e expressão imunoistoquímica (IQ) dos marcadores de prognóstico (p53 e ki-67) e de histogênese tumoral (Citoqueratinas 14, 17 e 19) em TOQCs associados ou não à SCNBC diagnosticados entre 1970 e 2009 no Hospital AC Camargo, São Paulo. Pacientes e Métodos. Estudo retrospectivo em que foram avaliados 74 pacientes, 60 não portadores da SCNBC (Grupo 1) e 14 portadores da SCNBC (Grupo 2). Os dados clínicos dos pacientes foram obtidos a partir dos prontuários médicos e sumarizados em fichas clínicas padronizadas para o estudo. Os pacientes do Grupo 1 apresentaram 61 TOQCs primários e 15 TOQCs recorrentes. O Grupo 2 apresentou 31 TOQCs primários e 8 recorrentes. Resultados. No Grupo 1, houve predomínio de pacientes nas 3ª e 4ª décadas de vida e no Grupo 2, na 2ª década (p = 0.02). De acordo com o sexo, houve predileção pelas mulheres em ambos os Grupos (53,33% no Grupo 1 e 64,29% no Grupo 2). A mandíbula foi mais frequentemente acometida nos dois Grupos (81,96% no Grupo 1 e 58,06% no Grupo 2). Contudo, a discrepância em relação à distribuição entre mandíbula e maxila foi menor no Grupo 2 (p = 0.009). O padrão radiográfico multilocular foi mais frequente no Grupo 1 (39,34%) e unilocular no Grupo 2 (48,39%) (p = 0.008). A associação de enucleação e curetagem foi frequentemente realizada em ambos os Grupos (55,74% no Grupo 1 e 96,78 no Grupo 2). A taxa de recorrência foi de 21,31% no Grupo 1 e 22,58% no Grupo 2. As manifestações clínicas mais comuns dos pacientes com SCNBC foram CBCs, calcificação da foice cerebral e pits palmares. De acordo com a análise imunoistoquímica dos marcadores CQ 14, CQ 17, CQ 19, p53 e ki-67, não foram observadas diferenças no padrão de expressão entre os Grupos de TOQCs avaliados. Conclusões. Os TOQCs associados à SCNBC acometem mais frequentemente indivíduos do sexo feminino e em idade mais precoce do que os TOQCs esporádicos. Múltiplos TOQCs foram frequentemente observados em pacientes sindrômicos e consequentemente houve menor discrepância em relação à distribuição entre mandíbula e maxila. O aspecto radiográfico unilocular é mais frequente em TOQCs associados à SCNBC e multilocular em TOQCs esporádicos. As taxas de recorrências foram similares em TOQCs associados e não associados à SCNBC. / Introduction. Keratocystic odontogenic tumor (KCOT) is a lesion of odontogenic origin which arise exclusively in gnatic bones and demonstrates high potential of local aggressiveness. KCOT may be associated with Nevoid Basal Cell Carcinoma Syndrome (NBCCS) which is characterized by development defects, multiple basal cell carcinoma (BCC) and skeletal anomalies. Around 65 to 100% of patients with NBCCS present multiple KCOT affecting jaws. Objective. Evaluate clinical, histopathological and immunohistochemical (IHC) expression of prognostic markers (p53 and ki-67) and tumor histogenesis (citokeratin 14, 17 and 19) in KCOT associated or not to NBCCS diagnosed between 1970 and 2009 at AC Camargo Hospital (São Paulo). Patients and methods. Retrospective study which has evaluated 74 patients, being 60 not associated with NBCCS (Group 1) and 14 associated with NBCCS (Group 2). Clinical data of patients was obtained from medical charts and summarized into standardized records for this study. The patients of Group 1 presented 61 primary KCOT and 15 recurrent KCOT. Group 2 presented 31 primary KCOT and 8 recurrent KCOT. Results. In Group 1, patients was frequently affected in 3rd and 4th decades and Group 2, in 2nd decade (p = 0.02). According to gender, a predilection for females was observed in both groups (53.33% in Group 1 and 64.29% in Group 2). The mandible was more affected in both Groups (81.96% in Group 1 e 58.06% in Group 2). However, the discrepancy regarding the distribution between mandible and maxilla was shorter in Group 2 (p = 0.009). Radiographic pattern more observed was multilocular in Group 1 (39.34%) and unilocular in Group 2 (48.39%) (p = 0.008). The treatment mostly performed was association of enucleation and curettage in both Groups (55.74% in Group 1 and 96.78 and Group 2). Recurrent rates were 21.31% in Group 1 and 22.58% in Group 2. Most clinical manifestations of NBCCS patient´s beyond KCOT were BCC, falx cerebri calcification and palmar pits. According to IHC analyses of Ck14, Ck 17, Ck19, p53 and ki-67, there were no differences of expression in all groups of KCOT evaluated. Conclusions. KCOT associated with NBCCS affects more commonly female individuals and in earlier age than in KCOT not related to NBCCS. Multiple KCOT were frequently observed in patients with NBCCS and consequently there was less discrepancy in relation to the distribution between maxilla and mandible. Multilocular pattern is more frequent in sporadic KCOT and unilocular in syndromic KCOT. Recurrence rates were similar in KCOT associated and not associated to NBCCS.

O CBC é o câncer mais comum hoje, causado pela UV que ao atingir a pele origina mutações no DNA que se não reparadas podem levar a tumorigênese. Este estudo avalia seqüências repetitivas (microssatélites e RAPD) na busca de marcadores moleculares e de genes envolvidos no surgimento deste tipo de tumor. Os padrões foram obtidos por PCR utilizando como molde DNA genômico de tumores, pele normal e leucócitos. Foram avaliados 34 tumores. Alterações nos microssatélites foram correlacionadas com o CBC esclerodermiforme e nos RAPD (OPB-08) com tumores micronodulares. Alterações de microssatélites e RAPDs apresentam correlação com o maior número de lesões em um mesmo paciente. Indicando um acompanhamento mais atento de pacientes mais alterados. A busca de novos genes envolvidos no CBC identificou DENND1A no cromossomo 9, putativamente menos expresso em cânceres de pele, porém com relação indeterminada com a carcinogênese e BANP/SMAR1, supressor tumoral que atua na via do p53, afeta a transcrição da ciclina D1 e inibe a sinalização da via TGFb promovendo a carcinogênese / BCC is the most common cancer today, caused by UV that generates mutation on the DNA of skin cells, which if not repaired may lead to tumorigenesis. This study evaluates repetitive sequences (microsatellites and RAPD) searching for molecular markers and genes involved in the development of this tumor. The patterns were obtained by PCR using as template genomic DNA from 34 tumors, normal skin and leucocytes. Microsatellite alterations are correlated with sclerosing BCC and RAPDs with micronodular BCC (OPB-08). Alterations in microsatellites and RAPD are correlated with an increase in the number of tumors in a patient. This indicates a more careful follow up for the more altered patients. The search for new genes involved with BCC identified DENND1A on chromosome 9, putatively less expressed in skin cancers, whose relation to carcinogenesis is undetermined and BANP/SMAR1, a tumor suppressor acting on the p53 pathway, affecting cyclin D1 transcription and inhibiting TGFb signaling pathway, promoting carcinogenesis

Genetic changes are hallmarks of cancer development involving the activation and/or inactivation of oncogenes and tumour suppressor genes, respectively. In non-melanoma skin cancer (NMSC) development, the initiation of genetic mutations results from exposure to solar ultraviolet radiation. Non-melanoma skin cancers are comprised of basal cell carcinoma (BCC) and squamous cell carcinoma (SCC). Several related cutaneous lesions also exist, of which solar keratoses (SK) are widely accepted as a precursor dysplasia to SCC development. The study of recurrent genetic changes present within NMSC and SK should help reveal causative mutations in skin cancer development. Such analysis could also elucidate links in the genetic similarity of these dysplasia. The rapid screening of numerical changes in DNA sequence copy number throughout the entire genome has been made possible by the advent of comparative genomic hybridisation (CGH). This technique enables the identification of net gains and loss of genetic material within a tumour DNA sample. Chromosomal regions of recurrent gain or loss identify loci containing putative oncogenes and tumour suppressor genes, respectively with potential roles in NMSC tumourigenesis. Used in conjunction with tissue microdissection and universal degenerate PCR techniques this can enable the elucidation of aberrations in small histologically distinct regions of tumour. Such a technique can utilize archival material such as paraffin embedded tissue, which is the major source of neoplastic material available for cancer research. This study used the CGH technique to investigate aberrations in BCC, SCC and SK samples. The screening of copy number abnormalities (CNAs) in BCC revealed that although these tumours were close to diploid and generally genetically stable, they did contain several recurrent aberrations. The loss of genetic material at 9q was identified in a third of BCC tumours studied. This is characteristic of inactivation of the PTCH tumour suppressor gene, a known attribute in some sporadic BCC development. Validation of this loss was performed via loss of heterozygosity, demonstrating good concordance with the CGH data. In addition the over-representation of the 6p chromosome arm was revealed in 47% of biopsies. This novel CNA is also commonly observed in other cutaneous neoplasias, including Merkel cell carcinoma and malignant melanoma. This suggests a possible common mechanism in development and or promotion in these cutaneous dysplasias, the mechanisms of which have yet to be clearly defined. In contrast to BCC, numerical genetic aberrations in SCC and SK were much more frequent. Several regions of recurrent gain were commonly shared between both dysplasias including gain of 3q, 4p, 5p, 8q, 9q, 14q, 17p, 17q and 20q. Common chromosomal regions of loss included 3p, 8p, 9p, 11p, 13q and 17p. In addition loss of chromosome 18 was significantly observed in SCC in comparison to SK, a possible defining event in SK progression to SCC. The identification of shared genetic aberrations suggests a clonal and genetic relationship between the two lesions. This information further supports the notion for re-classification of SK to an SCC in situ or superficial SCC. Finally, the CNAs detected have been similarly observed in other squamous cell-derived tumours, for example cervical and head and neck SCC. This provides further evidence to common mechanisms involved in the initiation, development and progression of SCC neoplasia. This study has identified a number of recurrent chromosomal regions, some of which are novel in NMSC development. The further delineation of these loci should provide additional evidence of their significance and degree of involvement in NMSC tumourigenesis. The identification of the cancer-causing genes mapped to these loci will further demarcate the genetic mechanisms of BCC and SCC progression. An understanding of the events involved in skin cancer formation and progression should shed additional light on molecular targets for diagnostics, management and therapeutic treatment.

Non-melanoma skin cancer (NMSC), comprised of basal cell carcinoma (BCC) and squamous cell carcinoma (SCC), is the most common cancer in Caucasians. Ultraviolet radiation (UVR) exposure is the most important environmental risk factor for both BCC and SCC development. However, the precise relationship between UVR and the risk of NMSC is complex, and the relationship may differ by skin cancer type. It has been hypothesized that intermittent patterns and childhood sunlight exposure are important for BCC while continuous (chronic) and lifelong (i.e. childhood and adulthood) sunlight exposure is important for SCC. Epidemiologic studies have demonstrated that cutaneous human papillomavirus (HPV) infection may also be a risk factor for developing NMSC. However, the pathway by which cutaneous HPV is associated with NMSC remains unclear. It is hypothesized that UVR exposure may interact synergistically with cutaneous HPV in NMSC development. The goal of the research study was to evaluate the relationship between levels of sunlight exposure and BCC and SCC and to investigate differences in sunlight-associated BCC and SCC risk by genus-specific cutaneous HPV serostatus. To address these goals, we conducted a clinic based case-control study of histologically confirmed BCC and SCC cases recruited from a university dermatology clinic and controls with no history of cancer and screened negative for current skin cancer. Logistic regression was used to calculate odds ratios (OR) and 95% confidence intervals (CI) for the associations between measures of sunlight exposure and BCC and SCC. Multiplicative interactions were tested by placing an interaction term for the product of genus-specific HPV seroreactivity and sunlight related factors in the logistic regression models. Measures of both intermittent and continuous patterns of sunlight exposure were associated with both types of skin cancer (i.e. BCC and SCC). Specifically, history of blistering sunburn (a marker of intermittent sunlight exposure) and occupational sunlight exposure (i.e. having a job in the sun for at least 3 months for >10 years) were both associated with BCC and SCC. The major differences in patterns of sunlight exposure between BCC and SCC were observed for sunlight exposure in one's thirties. Additionally, sunlight exposure in one's twenties was associated with SCC, regardless of pattern of exposure; similar associations were not observed for BCC. Measures of timing of sunlight exposure consistently demonstrated that childhood/adolescent sunlight exposure was more important for SCC than BCC. These included number of moles on the forearms and entire body (measure of increased childhood sunlight exposure), and younger age at first and tanning bed use. Younger age at first blistering sunburn was statistically significantly associated with both BCC and SCC. NMSC cases were more likely to be seropositive for cutaneous HPV antibodies compared to controls. Compared to tanning, having a propensity to sun burn (p=0.006), or poor tanning ability (p=0.003) were significantly associated with a higher seroprevalence to genus beta HPV types within SCC cases. Statistically significant interactions were observed between poor tanning ability and genus-specific seropositivity with NMSC. Specifically, the associations between poor tanning ability and BCC (p interaction=0.02) and SCC (p interaction=0.01) were significantly stronger among individuals that were seropositive for antibodies to genus alpha HPV types. Similarly, the association between poor tanning ability and SCC was stronger among those seropositive for genus beta HPV types (p interaction=0.001). No additional significant interactions were observed for BCC or SCC between cutaneous sensitivity, history of blistering sunburn, or cumulative sunlight exposure and genus-specific seroreactivity. In conclusion, associations with patterns of sunlight exposure appeared to be similar between BCC and SCC cases. With the exception of age at first blistering sunburn, factors measuring timing of sunlight exposure demonstrated stronger and statistically significant relationships with SCC. Additionally, of the sunlight related factors measured, only the associations between poor tanning ability and BCC and SCC were significantly modified by HPV seropositivity to types in genera alpha or beta.

No description available.

OBJETIVO: Comparar a acurácia da biópsia incisional em um sítio versus dois sítios, por trépano de 2 mm, em tumores palpebrais como teste diagnóstico do padrão histológico. MÉTODOS: Análise prospectiva das lesões com suspeita de malignidade palpebral no Setor de Plástica Ocular (HC-FMUSP), de novembro de 2012 a dezembro de 2014. As lesões foram fotografadas e suas características clínicas mensuradas por meio do \"software\" ImageJ 1.44. Os pacientes foram aleatoriamente divididos em dois grupos e submetidos à biópsia incisional de forma padronizada com trépano de 2 mm: grupo 1 em um sítio e grupo 2 em dois sítios do tumor. Os resultados diagnósticos das biópsias pré-operatórias foram comparados à peça cirúrgica (padrão-ouro). A avaliação anatomopatológica, tanto da biópsia como do padrão-ouro, foi realizada pelo mesmo médico patologista, e os resultados discordantes revisados por um segundo patologista. As medidas de sensibilidade, especificidade, valor preditivo positivo (VPP) e valor preditivo negativo (VPN), bem como a acurácia e o coeficiente Kappa, foram calculados para avaliar a concordância do diagnóstico da biópsia em relação ao padrão-ouro, comparando-se os dois grupos. Para as variáveis quantitativas, utilizou-se o teste Mann-Whitney, e, para as qualitativas, os testes de qui-quadrado ou exato de Fisher. RESULTADOS: Incluíram-se 166 lesões, sendo 69 no grupo 1 e 97 no grupo 2. O carcinoma basocelular (CBC) representou 63,25% da amostra total. Para todas as variáveis quantitativas e qualitativas, a distribuição entre os grupos foi semelhante e sem diferença estatística. Na identificação do padrão predominante, o grupo 2 apresentou duas vezes mais chance de resultado concordante em relação ao grupo 1, independentemente das demais variáveis: sexo, idade, tempo de evolução (TEV), maior diâmetro, área e margem. Os resultados mostraram melhores índices para o grupo 2, tanto para acurácia e coeficiente kappa quanto para sensibilidade, especificidade, VPP e VPN. A acurácia para diagnóstico do padrão predominante foi, no grupo 1, 53,60% e, no grupo 2, 71,10% com p-valor de 0,021. Em relação aos casos de CBC, a concordância para o subtipo agressivo no grupo 1 foi de 54,50% e, no grupo 2, foi de 73,80%, com diferença significativa (p-valor de 0,041). CONCLUSÕES: A biópsia incisional por trépano de 2 mm em dois sítios dos tumores palpebrais mostrou maior acurácia que em um sítio para o diagnóstico do padrão histológico predominante. Para os casos de CBC, possibilitou melhor diagnóstico do subtipo agressivo / PURPOSE: To compare 2-mm punch biopsy accuracy performed at one site versus two sites to diagnose eyelid tumors histological patterns. METHODS: Prospective analysis of eyelid tumors with suspicion of malignancy conducted at the Ocular Plastic Surgery Center (Hospital das Clínicas, University of São Paulo School of Medicine) from November 2012 until December 2014. Patients were randomly divided into 2 groups, and underwent a 2-mm punch biopsy: group 1 at one site and group 2 at two sites of the tumor. The tumors were photographed and measured with the software Image J 1.44. The results of the preoperative biopsies were compared with the surgical specimens (gold standard). The anatomopathological examination of the biopsy and the surgical specimen was performed by the same pathologist. Discordant results were reviewed by a second pathologist. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), accuracy and Kappa coefficients were calculated to determine the agreement between the 2-mm punch biopsy and the gold standard, comparing both groups. The statistical analysis included the Mann-Whitney test for quantitative variables and the chi-square test or the Fisher\'s exact test for qualitative variables. RESULTS: 166 lesions were included, 69 in group 1 and 97 in group 2. Basal cell carcinoma (BCC) accounted for 63.25% of the total sample. For all quantitative and qualitative variables, the distribution between the groups was similar and not statistically significant. In identifying the predominant pattern, biopsy by punch at two sites was two times more likely to agree in relation to one site, regardless of other variables: gender, age, disease duration, largest diameter, area and margin. Results showed higher scores for biopsy at two sites (accuracy, kappa coefficient, sensitivity, specificity, PPV and NPV). For the predominant pattern, the accuracy in group 1 was 53.60% and in group 2 was 71.10% (p = 0.021). Analyzing separately the cases of BCC, agreement for aggressive subtype in group 1 was 54.50% and in group 2 was 73.80%, with statistical difference (p = 0.041). CONCLUSIONS: Two sites of 2-mm punch biopsy in eyelid tumors showed higher accuracy than one site for the diagnosis of predominant pattern. For BCC, it showed better diagnostic results of aggressive subtype

Submitted by Leonardo Cavalcante (leo.ocavalcante@gmail.com) on 2018-04-24T17:10:12Z No. of bitstreams: 1 Arquivototal.pdf: 1560244 bytes, checksum: 121c5ccc4c7de435dbb28f4f19393b40 (MD5) / Made available in DSpace on 2018-04-24T17:10:13Z (GMT). No. of bitstreams: 1 Arquivototal.pdf: 1560244 bytes, checksum: 121c5ccc4c7de435dbb28f4f19393b40 (MD5) Previous issue date: 2017-05-03 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Basal cell carcinoma (BCC) is considered a tumor involving genetic, epigenetic and environmental factors. UVB radiation is considered to be one of the main physical agents involved in the carcinogenesis of the epidermis promoting DNA damage. In response to DNA damage the DNA repair mechanisms are activated, among them, the mismatch repair mechanism (MMR). The MMR system is an extremely important to maintain the fidelity of replication, however single nucleotide polymorphisms (SNPs) in genes involved in MMR should be considered an important factor for CBC carcinogenesis. The present study carried out the genotyping of SNPs rs560246973 (T> C), rs2303425 (-118 T> C) in the MSH2 gene and rs565410865 (G> T) in the MLH1 gene, in 100 samples of paraffin-embedded tissue from patients diagnosed with basal cell carcinoma. The results were obtained by means of the Dideoxy Single Genotype Allele Specific PCR-DSASP genotyping method. SNPs rs565410865 MLH1 and rs560246973 (C> T) MSH2 showed a statistically significant association with the susceptibility and risk of developing BCC. The results suggest that SNPs rs565410865 MLH1 and rs560246973 (C> T) MSH2 are potential molecular markers associated with susceptibility to the development of BCC in the analyzed samples. . / O carcinoma basocelular (CBC) é considerado um tumor que envolve fatores genéticos, epigenéticos e ambientais. Sendo a radiação UVB considerada um dos principais agentes físicos envolvido na carcinogênese da epiderme promovendo danos ao DNA. Em resposta aos danos no DNA os mecanismos de reparo do DNA são ativados, entre eles, o Mecanismo de Reparo de Mal Pareamento (MMR). O sistema MMR é uma via extremamente importante para manter a fidelidade da replicação, no entanto polimorfismos de nucleotídeo único (SNPs) em genes envolvidos no MMR deve ser considerado fator importante para carcinogênese do CBC. O presente estudo realizou a genotipagem dos SNPs rs560246973 (T>C), rs2303425 (-118 T>C) no gene MSH2 e rs565410865 (G>T) no gene MLH1, em 100 amostras de tecido parafinado de pacientes diagnosticados com carcinoma basocelular. Os resultados foram obtidos por meio do método de genotipagem Didesoxi Único Alelo Específico PCR- DSASP. Os SNPs rs565410865 MLH1 e rs560246973 (C>T) MSH2 apresentaram associação estatisticamente significativa à susceptibilidade e o risco de desenvolver CBC. Os resultados sugerem que SNPs rs565410865 MLH1 e rs560246973 (C>T) MSH2 são potenciais marcadores moleculares associados à susceptibilidade ao desenvolvimento do CBC nas amostras analisadas.

Submitted by Vasti Diniz (vastijpa@hotmail.com) on 2017-09-06T12:44:39Z No. of bitstreams: 1 arquivototal.pdf: 1491913 bytes, checksum: 48f18b769a4ddee1245aef6c202388b1 (MD5) / Made available in DSpace on 2017-09-06T12:44:39Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 1491913 bytes, checksum: 48f18b769a4ddee1245aef6c202388b1 (MD5) Previous issue date: 2017-02-08 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Basal Cell Carcinoma (BCC) is a frequent neoplasm in humans and its main etiological factor is exposure to solar radiation. Although genetic and epigenetic changes can activate proto-oncogenes, inactivate tumor suppressor genes and repair mechanism genes, the cell has several mechanisms that contribute to the maintenance of genomic stability. Mutations in repair genes can lead to tumor progression and loss of genome integrity leading to the onset of cancer. Nucleotide excision repair (NER) is an important mechanism primarily used to repair injuries caused by UV. The objective of this study was to evaluate single nucleotide polymorphisms (SNP) of XPA and XPC genes and the risk of developing BCC. One hundred samples of paraffined tissue from patients from the State of Paraíba with histopathological diagnosis of BCC were analyzed for each polymorphism. The results were obtained by a newly developed genotyping method, the Dideoxy Unique Allele Specific - PCR, a method that presents high sensitivity and low cost. Graphpad Prism 6.01 software was used for the statistical analysis and application of Chi-square and Fisher's exact test. The SNP rs535425175 of the XPC gene showed a significant association with the BCC in the analyzed samples (X2 = 14.51 and P <0.005). Whereas the SNPs rs745769173 of the XPA gene and rs761106780 of the XPC gene are in the Hardy-Weinberg equilibrium, not showing any association with the neoplasia. The results suggest that the SNP rs535425175 of the XPC gene may be considered a risk factor associated with the development of BCC. / O Carcinoma Basocelular (CBC) é uma neoplasia frequente em seres humanos e seu principal fator etiológico é a exposição à radiação solar. Embora alterações genéticas e epigenéticas possam ativar proto-oncogenes, inativar genes supressores de tumor e genes do mecanismo de reparo, a célula apresenta vários mecanismos que contribuem para a manutenção da estabilidade genômica. Mutações em genes de reparo podem levar a progressão tumoral e à perda da integridade do genoma levando ao surgimento do câncer. O reparo por excisão de nucleotídeo (NER) é um importante mecanismo utilizado principalmente para reparar lesões causadas por UV. O objetivo deste trabalho foi avaliar polimorfismos de nucleotídeo único (SNP) dos genes XPA e XPC e o risco de desenvolver CBC. Foram analisadas 100 amostras de tecido parafinado de pacientes do Estado da Paraíba com diagnóstico histopatológico de CBC para cada polimorfismo. Os resultados foram obtidos por um método de genotipagem recentemente desenvolvido, o Didesoxi Único Alelo Específico – PCR, método que apresenta alta sensibilidade e de baixo custo. O software Graphpad Prism 6.01 foi utilizado para as análises estatísticas e aplicação de teste Qui-quadrado e Exato de Fisher. O SNP rs535425175 do gene XPC apresentou associação significativa com o CBC nas amostras analisadas (X2=14,51 e P<0,005). Enquanto que os SNP rs745769173 do gene XPA e rs761106780 do gene XPC estão no equilíbrio de Hardy-Weinberg, não apresentando associação com a neoplasia. Os resultados sugerem que o SNP rs535425175 do gene XPC pode ser considerado um fator de risco associado ao desenvolvimento de CBC. Palavras-chaves: Carcinoma Basocelular, Família XP, Reparo por excisão de nucleotídeo, Polimorfismo de nucleotídeo único, Genotipagem. VII

Existe grande interesse na determinação das bases genéticas do carcinoma basocelular (CBC) que expliquem seu fenótipo pouco agressivo e comportamento metastático infreqüente. Investigamos a instabilidade de microssatélites (MSI) e perda de heterozigosidade (LOH) nos microssatélites D6S251 (6q14) e D6S252 (6q16) de CBCs esporádicos de alto e baixo risco histológico através da análise de bandas obtidas pelo gel de poliacrilamida após PCR em comparação com o tecido normal. Não houve alteração do microssatélite D6S252 nas 15 amostras estudadas. Para o microssatélite D6S251, houve alterações em 6 das 26 amostras estudadas (23,07%). MSI e LOH ocorreram em 46,15% das amostras de alto risco (respectivamente 15,38% e 30,76), o que sugere o provável envolvimento da região 6q14 na diferenciação histológica do CBC / A lot of interest lies in determining the genetic basis of basal cell carcinoma (BCC) to explain the lack of aggressive phenotype and infrequent metastatic behavior. We have analyzed the microsatellite instability (MSI) and loss of instability (LOH) in the D6S251 (6q14) and D6S252 (6q16) microsatellites patterns of histological low- high-risk sporadic BCC tumor samples using PCR-based assay in comparison with normal tissue. We have not found any alteration in D6S252 microsatellite 15 samples studied. We have encountered D6S251 alterations in 6 of 26 BCC samples (23.07%).MSI and LOH occurred in 46.15% of high-risk samples (15.38% and 30.76%), These results probably suggests participation of 6q14 region in histological differentiation of BCC