SILVIA VANESSA LOURENCO
Projetos de Pesquisa
Unidades Organizacionais
ODE, FO - Docente
LIM/06 - Laboratório de Imunopatologia da Esquistossomose e outras Parasitoses, Hospital das Clínicas, Faculdade de Medicina - Líder
LIM/06 - Laboratório de Imunopatologia da Esquistossomose e outras Parasitoses, Hospital das Clínicas, Faculdade de Medicina - Líder
4 resultados
Resultados de Busca
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- Claudin and p53 expression in vulvar lichen sclerosus and squamous-cell carcinoma(2011) SADALLA, Jose Carlos; LOURENCO, Silvia Vanessa; SOTTO, Mirian Nacagami; BARACAT, Edmund Chada; CARVALHO, Jesus PaulaAims Vulvar squamous-cell carcinoma (SCC) is a rare gynaecological cancer. Vulvar SCC has been shown to develop from vulvar intraepithelial neoplasias, which are related to lichen sclerosus (LS). Most studies to date have compared vulvar SCC with LS only morphologically, but no detailed molecular analysis has been performed. The objective was to compare claudin and p53 expression in these diseases and determine if there was any association with expression and vulvar SCC progression. Methods Immunohistochemical analysis was performed in order to determine expression of p53 and claudin 1, 2, 3, 4, 5, 7 and 11 in human vulvar tissue samples from LS, SCC and control patients. Results Claudin 1, 2, 3, 4 and 5 were expressed comparably in the three groups. Claudin 7 and 11 expression was significantly decreased in LS and SCC samples compared with the control group. Expression of p53 was significantly increased in SCC and LS patient samples compared with the control group. Conclusions Claudin 7 and 11 were not expressed in LS and SCC. However, there was no significant difference in expression of any of the claudins between the LS and SCC samples. Furthermore, p53 expression is the highest in SCC patients and lowest in the control group. However, expression of p53 did not vary between samples from isolated LS and LS associated SCC patients, suggesting that increased p53 expression is not the determining factor in the progression of LS lesions to SCC.
- Evaluation of the efficacy of photodynamic therapy for the treatment of actinic cheilitis(2017) CHAVES, Yuri N.; TOREZAN, Luis Antonio; LOURENCO, Silvia Vanessa; NETO, Cyro FestaIntroductionActinic cheilitis (AC) is a lip intraepithelial neoplasia, whose cells present alterations similar to those presented by invasive squamous cell carcinomas (SCCs). ObjectiveTo conduct clinical and laboratory evaluation by histopathology and immunohistochemistry of the efficacy of actinic cheilitis treatment using photodynamic therapy (PDT) with methyl aminolevulinate (MAL) and noncoherent red light. Materials and methodsPatients with actinic cheilitis detected by histopathological examination were submitted to two sessions of photodynamic therapy with a two-week interval between them. They were examined immediately after the sessions, four, six, and twelve weeks after beginning treatment when a new biopsy was carried out. Clinical histopathological and immunohistochemical parameters were evaluated before and after treatment. ResultsOf the 23 patients who underwent biopsy, 16 completed two photodynamic therapy sessions and the material of one patient was insufficient for immunohistochemistry. Complete clinical response was achieved in 62.5% (10 of 16 patients) and 37.5% still remained with clinical evidence of AC. In spite of this, no case of cure by histopathological analysis was found. There was no significant statistical change among the values of Ki-67, survivin, and p53 observed before and after treatment. ConclusionPhotodynamic therapy, as carried out in this trial, was not an efficacious therapeutic option for treating patients with actinic cheilitis included in this sample.
- Actionable Mutation Profile of Sun-Protected Melanomas in South America(2022) HSIEH, Ricardo; NICO, Marcello M. S.; CAMILLO, Claudia M. C.; OLIVEIRA, Katia K.; CARRARO, Dirce M.; SANGUEZA, Martin; V, Silvia LourencoMelanomas that arise in sun-protected sites, including acral and oral mucosal melanomas, are likely under the control of unique, specific mechanisms that lead to mutagenesis through various pathways. In this study, we examined somatic mutations in tumors by targeted sequencing using a custom Ion Ampliseq Panel, comprising hotspots of 14 genes that are frequently mutated in solid tumors. Tumor DNA was extracted from 9 formalin fixation, paraffin-embedded sun-protected melanomas (4 primary oral mucosal melanomas and 5 acral lentiginous melanomas), and we identified mutations in the NRAS, PIK3CA, EGFR, HRAS, ERBB2, and ROSI genes. This study reveals new actionable mutations that are potential targets in the treatment of photo-protected melanomas. Additional studies on more of these melanoma subtypes could confirm our findings and identify new mutations.
- Adhesion Molecules in Primary Oral Mucosal Melanoma: Study of Claudins, Integrins and Immunoglobulins in a Series of 35 Cases(2013) BOLOGNA, Sheyla Batista; NICO, Marcello Menta S.; HSIEH, Ricardo; COUTINHO-CAMILLO, Claudia Malheiros; BUIM, Marcilei E.; FERNANDES, Juliana Dumet; SANGUEZA, Martin; SOARES, Fernando Augusto; LOURENCO, Silvia VanessaPrimary oral mucosal melanoma is a rare aggressive tumor. Recent studies have demonstrated a correlation between increased tumor invasion and the metastatic phenotype and altered adhesion molecule expression profiles. The present study analyzed the expression of integrins, claudins, and immunoglobulin-like adhesion molecules in oral mucosal melanomas and correlated results with clinical parameters. Immunohistochemical analyses of the expression patterns of these molecules were performed on thirty-five cases of primary oral mucosal melanomas organized in a tissue microarray. The results were correlated with clinical and histological features of the cohort. A number of integrin subunits were negative and this was related with vascular invasion. Positivity of integrin beta-3 and CD166 (activated leukocyte cell adhesion molecule) was statistically associated with extensive vascular invasion (P < 0.05). Lower expression of CD54 (intercellular cell adhesion molecule) was associated with cases with extensive necrosis. Most cases with metastatic disease were negative for CD66 (carcinoembryonic antigen-related cell adhesion molecule). Several subunits of claudins were negative and, although not statistically significant, this lack of expression was partially associated with histological factors of poor prognosis. Altered patterns of adhesion molecule expression, mainly integrins and immunoglobulin-like proteins, may participate in the pathogenesis and outcome of oral mucosal melanomas.