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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.
61

Instabilidade genômica em carcinoma basocelular humano revelada através da análise de sequências repetitivas / Genomic instability in baseal cell carcinoma revealed by repetitive sequences analysis

Capitanio, Juliana Silva 15 December 2009 (has links)
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
62

Genetic Aberrations in Non-Melanoma Skin Cancer

Ashton, Kevin John, K.Ashton@griffith.edu.au January 2002 (has links)
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.
63

Case-Control Study of Sunlight Exposure and Cutaneous Human Papillomavirus Seroreactivity in Basal Cell and Squamous Cell Carcinomas of the Skin

Iannacone, Michelle R. 01 January 2011 (has links)
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.
64

Interaction of the Hedgehog and vitamin D receptor signaling pathways in Patched associated cancers

Linder, Benedikt 07 May 2015 (has links)
No description available.
65

Estudo de associação dos SNPS dos genes MLH1 e MSH2 à susceptibilidade ao desenvolvimento do carcinoma basocelular no Estado da Paraíba

Calixto, Poliane da Silva 03 May 2017 (has links)
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.
66

Estudo da associação de SNPs dos genes do mecanismo de reparo por excisão de nucleotídeo em carcinoma basocelular no Estado da Paraíba

Maia, Mayara dos Santos 08 February 2017 (has links)
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
67

Painel imunoistoquímico para distinção entre tricoepitelioma e carcinoma basocelular desenvolvido utilizando a técnica do TMA / Diagnostic utility of immunohistochemical panel in distinguishing trichoepithelioma and basal cell carcinoma: evaluation using tissue microarray samples

Antonio José Tebcherani 24 April 2012 (has links)
O diagnóstico das neoplasias cutâneas do folículo piloso, particularmente do tricoepitelioma (TE), frequentemente representa dificuldade diagnóstica com o carcinoma basocelular (CBC). As semelhanças clínicas e histopatológicas somadas aos artefatos de amostragem (amostras exíguas por biopsias incisionais ou parcialmente danificadas por esmagamento ou fulguração) podem provocar situações de dificuldade na diagnose diferencial entre as duas neoplasias. O diagnóstico de certeza é importante, pois o CBC tem caráter agressivo local e, quando não totalmente excisado, infiltra os tecidos adjacentes. O TE é uma lesão benigna, sem capacidade de invasão local, não havendo recomendação de excisão com margem cirúrgica. Vários marcadores imunoistoquímicos têm sido propostos na literatura médica para auxiliar no diagnóstico diferencial entre o TE e o CBC. Esses estudos, entretanto, têm resultados conflitantes que podem estar relacionados à pequena casuística avaliada, que geralmente não excede 50 casos de TE. A técnica do arranjo em matriz de amostras teciduais, tissue microarray (TMA), permite a avaliação de um número grande de amostras teciduais, que podem ser submetidas de modo simultâneo aos procedimentos das reações imunoistoquímicas. O objetivo do presente estudo foi o de submeter uma ampla amostra de TE e CBC, obtida através da técnica de TMA, aos marcadores imunoistoquímicos descritos, com a finalidade de identificar um marcador, ou painel de marcadores, capaz de auxiliar a diferenciação do TE do CBC. Cortes histológicos de quatro blocos de TMA representando espécimes de 162 TE e 328 CBC foram submetidos às reações imunoistoquímicas com os anticorpos CD34, BCL-2, CD 10, antígeno de membrana epitelial (EMA), citoqueratinas (CK) 20 e 15, D2-40 e 34 E12. A fim de facilitar a avaliação dos resultados e padrões de expressão antigênica, os espécimes foram digitalizados para obtenção de lâminas histológicas virtuais. Estas foram analisadas por meio de um programa de computador. Fez-se inicialmente a análise dos resultados de 85 TE e 62 CBC representados no primeiro bloco de TMA. Esta verificação identificou a expressão dos marcadores CD34, CD10, EMA, CK15, CK20 e D2-40 com diferença significativa entre os TE e os CBC. Procedeu-se a seguir a avaliação da imunomarcação de toda a casuística. As análises estatísticas de regressão linear multifatorial e regressão logística multifatorial indicaram os marcadores e padrões de expressão em ordem decrescente de importância: D2 40 positivo em células tumorais periféricas, CK 15 positivo em células tumorais periféricas, CD10 positivo no estroma tumoral, CK 20 positivo em células tumorais periféricas e positividade estromal de CD 34. A regressão logística evidenciou ainda que, na amostra examinada, a presença de três ou quatro desses marcadores, com exceção do CD 34, pode identificar 35,9% dos TE. Nossos resultados, obtidos pelo estudo de casuística expressiva, são concordantes com os achados de outros trabalhos que sugerem que o TE e o CBC são neoplasias que estão em diferentes pontos da mesma linhagem de diferenciação dos tumores basalóides foliculares e que, por este motivo, podem expressar os mesmos marcadores/perfil antigênico epitelial e estromal. Embora o painel de quatro anticorpos acima relatado possa ser de grande ajuda, e até mesmo identificar 35,9% dos TE, os critérios histopatológicos clássicos e clínicos ainda devem ser os principais guias para o diagnóstico diferencial entre o TE e o CBC / Trichoepithelioma is a benign neoplasm that shares both clinical and histological features with basal cell carcinoma. It is important to distinguish these neoplasms because they have different clinical behavior and require proper therapeutic planning. Many studies have addressed the use of immunohistochemistry to improve the differential diagnosis of these tumors. These studies present conflicting results when addressing the same markers, probably due to the small number of basaloid tumors that comprised their studies, which generally did not exceed 50 cases. We built a tissue microarray with 162 trichoepithelioma and 328 basal cell carcinoma biopsies and tested a panel of immune markers composed of CD34, CD10, epithelial membrane antigen, BCL-2, cytokeratins 15 and 20 and D2-40. The results were analyzed using multiple linear and logistic regression models. This analysis revealed a model that could differentiate trichoepithelioma from basal cell carcinoma in 35,9% of the cases. The panel of immunohistochemical markers required to differentiate between these tumors was composed of CD10, cytokeratin 15, cytokeratin 20 and D2-40. The results obtained in this work were generated from a large number of biopsies and resulted in the confirmation of overlapping epithelial and stromal immunohistochemical profiles from these basaloid tumors. The results also corroborate the point of view that trichoepithelioma and basal cell carcinoma tumors represent two different points in the same line of differentiation. Despite the use of panels of immune markers, histopathological criteria associated with clinical data certainly remain the best guideline for the differential diagnosis of trichoepithelioma and basal cell carcinoma
68

Preditores da extensão subclínica e do número de fases da cirurgia micrográfica de Mohs no carcinoma basocelular / Predictors of subclinical spread and number of stages in Mohs micrographic surgery for treatment of basal cell carcinoma

Bruno de Carvalho Fantini 03 November 2015 (has links)
Introdução: O carcinoma basocelular (CBC) é o tipo mais comum de câncer da pele não-melanoma na população mundial. A elevada prevalência do acometimento da face determina elevada morbidade, a despeito da baixa taxa de mortalidade. Localização, dimensão, subtipo histológico, recidiva e delimitação imprecisa relacionam-se ao risco de invasão e destruição local, sendo critérios de indicação da cirurgia micrográfica de Mohs (CMM), padrão ouro para tratamento do CBC, por elevadas taxas de cura e preservação de tecido sadio. Objetivo: Analisar possíveis preditores da extensão subclínica e do número de fases da CMM para o CBC, em conjunto com o emprego de imuno-histoquímica (IHQ). Métodos: Amostra de 101 casos de CBC excisados por CMM, delimitados previamente por dermatoscopia, foi analisada quanto ao perfil demográfico, características e possíveis relações entre as variáveis determinantes do risco para realização de duas ou mais e três ou mais fases na CMM. Marcação por IHQ dos anticorpos Ber-EP4, MNF-116, E-Caderina e VGEF foi realizada em onze casos de diferentes subtipos do CBC. Resultados: Na amostra, com 49,5% de tumores recidivados, predominou o sexo feminino (58,4%), com idade média de 60,2 anos e localização no segmento cefálico, sendo 52,5% dos tumores na região nasal. Subtipo histológico de alto risco em 69,3%, sendo 64,7% entre os primários e 74% entre os recidivados. Em 46,5% evidenciou-se mais de um tipo histológico, coexistindo baixo e alto risco em 33,7%; 97% apresentou mais de um critério de risco para indicação de CMM, predominando a localização em 91,1%, sendo baixas aquelas por delimitação imprecisa (12,9%) e margens comprometidas (6,9%); 60,4% dos tumores foram removidos por uma fase cirúrgica, 39,6% por duas ou mais e 10,9% por três ou mais. Recidiva elevou as chances de 2 fases para remoção completa (OR=2,40 I.C.95% 1,06 5,44; teste do X2 = 4,47, p= 0,03), assim como localização na região nasal e zona H (p = 0,04 e p = 0,056, respectivamente). O maior número de critérios elevou as chances de 2 fases e 3 fases (p = 0,02 e p = 0,03, respectivamente). As intensidades de marcação com Ber-EP4 e E-Caderina foram mais acentuadas no subtipo micronodular comparadas ao esclerodermiforme. Todos os marcadores evidenciaram os ninhos neoplásicos multifocais dispersos e em meio ao intenso processo infamatório. O VEGF, mostrou marcação mais intensa e evidente no infiltrado inflamatório perineoplásico. Conclusões: A coexistência de padrões e predomínio do alto risco nos CBC primários e recorrentes evidenciam potenciais causas de recidiva, invasão e destruição, e da indicação da CMM. Localização cefálica e recorrência são critérios que corroboraram tal indicação e, o maior número de critérios presentes, a predição da extensão subclínica. A dermatoscopia auxiliou na delimitação pré-cirurgica do CBC. Idade avançada pode exigir mais fases para remoção do CBC. Marcadores imunohistoquímicos podem ser úteis para evidenciar a neoplasia nos tecidos ou em meio a processo infamatório. O reconhecimento de fatores preditivos é auxiliar na decisão terapêutica, no planejamento cirúrgico e na obtenção das altas taxas de cura por meio da CMM. / Introduction: Basal cell carcinoma (BCC) is the most common type of non-melanoma skin cancer and the most frequently occurring form of cancer worldwide. BCC occurs mostly on the face, and despite low mortality rate, it generates high morbidity. Some features such as size, histological subtype, location, recurrence, poor delimitation and others are predictors of recurrence. Mohs micrographic surgery (MMS) is the gold-standard treatment for BCC. It has the highest cure rates and causes less damage to healthy tissue than other options. Objective: This study aims to analyze predictors of subclinical spread and number of stages in MMS for removing BCC and the use of immunohistochemistry (IHC). Methods: We selected 101 patients with BCC and indication for MMS. Analyzed the demographic profile of the patients and relations between the characteristics of tumor risk and number of surgical stages (one, two or more and three or more stages). Immunostaining (Ber-EP4 antibodies, MNF-116, E-Cadherin and VGEF) was performed in 11 BCC with different histological subtypes. Results: Among 101 BCC, 49,5% was recurrent. There was a female predominance (58.4%) with mean age of 60.2. There was also a predominance on the face, most of them located on the nose (52,5%). Histological types with high risk of recurrence predominated (69.3%), 64,7% among primary and 74% among recurrent ones. 46.5% tumors had more than one histological type, with low and high risk in the same lesion in 33.7%. Most BCC (97%) had more than one criteria to be treated by MMS and location was the most frequent (91,1%). Poorly defined (12.9%) and positive margins (6.9%) occurred only in a few cases. 60,4% were removed by one surgical stage; 39,6% by 2 and 10,9% needed 3 stages. Among recurrent BCC, the chance of 2 surgical stages was 2,4 times compared to primary tumors (p= 0,03). BCC located on nasal region and mask areas of the face were also associated with 2 stages (p = 0.04 and p = 0.056, respectively). The number of criteria was also associated with 2 and 3 stages (p = 0.02 and p = 0.03, respectively). Intensity of Ber-EP4 and E-Cadherin were more pronounced in micronodular subtype compared to morpheaform. In areas with intense inflammatory cell infiltrate, anti-Ber-EP4, anti-MNF116 and anti-E-Cadherin were useful to highlight the neoplastic cells. Anti-VEGF showed up clearly in the inflammatory infiltrate around tumor. Conclusion: Mixed histopathological pattern observed in many tumors and predominance of high-risk histology in primary and recurrent BCC highlight potential causes of recurrence, invasion, destruction, and indication for MMS. Location and recurrence stood out as a criterion for MMS and a greater number of criteria was associated with subclinical extension of the BCC. Age was also associated with an increased number of stages. Dermoscopy helped in the demarcation of surgical margins. As for the IHC, it would be useful to highlight BCC in areas with intense inflammation. Recognition of predictive factors is important in therapeutic decision, surgical planning and to obtain the highest cure rates by MMS.
69

Instabilidade genômica em carcinoma basocelular humano revelada através da análise de sequências repetitivas / Genomic instability in baseal cell carcinoma revealed by repetitive sequences analysis

Juliana Silva Capitanio 15 December 2009 (has links)
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
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Expressão de citocinas, linfócitos, fator de crescimento endotelial vascular (VEGF) e antígeno leucocitário humano G (HLA-G) em carcinoma basocelular / Expression of cytokines, lymphocytes, endothelial growth factor (VEGF) and human leukocyte antigen G (HLA-G) in basal cell carcinoma

Andrezza Telles Westin 18 July 2014 (has links)
A elevada e crescente prevalência do carcinoma basocelular (CBC) na população caucasiana e o seu marcante predomínio entre os cânceres cutâneos não-melanoma despertam interesse para a elucidação dos mecanismos envolvidos no seu desenvolvimento. Os vários subtipos da neoplasia possuem características de interesse para um modelo de estudo, a fim de identificar os fatores determinantes dos diferentes padrões de crescimento. Objetivo: Neste estudo buscamos analisar, por meio da expressão de citocinas, linfócitos, VEGF e HLA-G, os possíveis mecanismos imunomoduladores envolvidos nos diferentes padrões de crescimento, subtipos e localizações topográficas do CBC. Métodos: Em 26 amostras de fragmentos dos subtipos nodular e superficial de CBC primários, foram analisadas a expressão de CD3, CD4, CD25, FOXP3, HLA-G e VEGF, por meio imunoistoquímica (IHQ), e de IL-4, IL-6, IL-8, IL-10, IL-17, IL-23, FOXP-3 e IFN-gama, por meio da reação em cadeia da polimerase em tempo real quantitativa (qPCR). Resultados: Na amostra (n=26), houve discreto predomínio de homens (54%), com idade variando entre 35 a 89 anos e média de 72,96 anos; 84,62% dos CBC eram localizados em área fotoexposta, 53,85% não-cefálicos (14/26) e 46,15% cefálicos (12/26). CBC nodulares apresentaram um infiltrado inflamatório mais evidente e concentrado ao redor dos blocos neoplásicos; CBC superficiais apresentaram um infiltrado inflamatório difuso por toda a derme, e discretamente mais intenso nas áreas adjacentes aos blocos tumorais. A expressão de todos os marcadores foi mais evidente no sítio perineoplásico (PN) comparado ao interior, das células neoplásicas (Cneo). Distintamente de outros marcadores, notou-se acentuada frequência da expressão de CD25+ e HLA-G nas Cneo. Nas Cneo dos CBCn, evidenciou-se elevada frequência de células marcadas em intensidade moderada para HLA-G (p=0,04) e em intensidade leve para FOXP3 (p = 0,037), quando comparados aos CBCs. A expressão de CD4+ no infiltrado PN foi mais frequente nos tumores não-cefálicos (p=0,02) comparados aos cefálicos. A expressão de citocinas IL-6 IL-8, IL-17 foi maior nos dois subtipos de CBC, nodular e superficial, comparada à da pele normal. CBC cefálicos apresentaram maior expressão de IL-4 (p=0,02), enquanto aqueles de localização não-cefálica expressaram mais IL-8 (p=0,002). Conclusão: A composição e a localização do infiltrado inflamatório corroboram a resposta imunológica mediada por células T CD3+ e CD4+ no CBC. A participação de linfócitos CD25+, FOXP3+ e do HLA-G caracteriza uma ação imunomoduladora, e a presença das interleucinas IL-8 e do perfil Th17, IL-6 e IL-17, podem favorecer a neovascularização e a supressão de células efetoras no microambiente do CBC propiciando o seu desenvolvimento e escape tumoral. / Introduction: The high and increasing prevalence of basal cell carcinoma (BCC) in the Caucasian population, and its striking predominance between non-melanoma skin cancers arouse interest for the elucidation of the mechanisms involved in its development. Its various subtypes have characteristics of interest for a study model in order to identify the determinants of different patterns of growth. Objective: This study aims to analyze the possible immunomodulatory mechanisms involved in the different growth patterns, and topographic locations subtypes of BCC through the expression of cytokines, lymphocytes, VEGF and HLA-G. Methods: In 26 fragments samples of primary BCC, subtypes nodular and superficial, we analyzed the expression of CD3, CD4, CD25, FOXP3, HLA-G and VEGF by immunohistochemistry (IHC) technique, and of cytokines IL-4, IL-6, IL-8, IL-10, IL-17, IL-23, FOXP-3 and IFN- by quantitative real time polymerase chain reaction (qPCR). Results: The sample (n = 26) had a slight predominance of men (54%), aged between 35-89 years, mean age 72.96 years; 84.62% of the BCC were located in sun-exposed area, 53.85% (14/26) non-cephalic and 46.15% (12/26) cephalic. Nodular BCC showed a more evident and concentrated inflammatory infiltrate around the tumor blocks; while superficial BCC showed a diffuse inflammatory infiltrate throughout the dermis, and slightly more intense in tumor blocks adjacent areas. The expression of all markers was evident at the perineoplastic (PN) sites compared to neoplastic cells (Cneo). Differently from other markers, we noticed strong frequency expression of CD25+ and HLA-G within the Cneo. In Cneo of BCCn, it became apparent high frequency of moderate HLA-G marked cells (p = 0.04) and at low intensity for FOXP3 (p = 0.037) when compared to BCCs. The expression in CD4+ infiltrate was more frequent in PN non-cephalic tumors (p = 0.02) compared with cephalic. The expression of IL-6 IL-8, IL-17 was higher in both subtypes of BCC, nodular and superficial, compared to normal skin. Cephalic BCC showed higher expression of IL-4 (p=0,02) while those from non-cephalic location expressed more IL-8 (p=0,002). Conclusion: The composition and location of the inflammatory infiltrate corroborate the immune response mediated by CD3+ and CD4+ T cells on the BCC. The involvement of HLA-G, CD25+ and FOXP3 lymphocytes features an immunomodulary action, and the presence of interleukin IL-8 and Th17 profile (IL-6 and IL-17) may promote neovascularization and suppression of effector cells in the BCC microenvironment providing its development and tumor escape.

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