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
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- CD24 and CD44 in salivary gland pleomorphic adenoma and in human salivary gland morphogenesis: differential markers of glandular structure or stem cell indicators?(2013) IANEZ, Renata C. F.; COUTINHO-CAMILLO, Claudia M.; BUIM, Marcilei E.; PINTO, Clovis A. L.; SOARES, Fernando A.; LOURENCO, Silvia V.Aims Salivary gland neoplasms originate from salivary gland compartments, to which they are histologically related. Pleomorphic adenoma (PA) is a benign salivary gland neoplasm that comprises epithelial and myoepithelial cells and a complex stroma, whose structure, architecture and origin (from intercalated ducts) suggest stem cell participation. We compared the expression of CD24 and CD44 in PA and in developing human salivary glands to investigate whether these markers can be considered as cancer stem cell markers. Methods and results One hundred and one cases of PA and salivary gland specimens from 20 human fetuses were examined by immunohistochemistry and real-time reverse transcription polymerase chain reaction (RT-PCR). All PAs were positive for CD24 and CD44 by immunohistochemistry: neoplastic luminal structures were positive for CD24; modified myoepithelial cells were positive for CD44. In fetal salivary glands, these markers were restricted to the intercalated duct region. Real-time RT-PCR assays detected increased expression of CD44, but not CD24, in PA specimens in comparison with normal salivary gland controls. Conclusions PA and stem cells share the expression of CD24 and CD44; their value as markers of neoplastic cell multipotency and the implications of their expression for tumour behaviour are yet to be determined.
- Radiologic and histologic findings in Sjogren's sensory neuronopathy(2019) GRATIVVOL, Ronnyson Susano; CAVALCANTE, Wagner Cid Palmeira; VENTURA, Lais Maria Gomes de Brito; CALDAS, Vitor Marques; LUCATO, Leandro Tavares; LOURENCO, Silvia Vanessa; HEISE, Carlos Otto; NITRINI, Ricardo
article 14 Citação(ões) na Scopus MAP Kinase Pathways: Molecular Roads to Primary Acral Lentiginous Melanoma(2015) FERNANDES, Juliana D.; HSIEH, Ricardo; FREITAS, Luiz A. R. de; BRANDAO, Miguel A. R.; LOURENCO, Silvia V.; SANGUEZA, Martin; NICO, Marcello M. S.The etiology and pathogenesis of lentiginous acral melanomas are poorly understood. Recent studies have postulated that DNA repair mechanisms and cell growth pathways are involved in the development of melanoma, particularly changes in the MAPK pathways (RAS, BRAF, MEK 1/2, and ERK 1/2). The aim of this study is to assess the status of the MAP kinase pathways in the pathogenesis of acral melanomas. The authors examined the components of the RAS-RAF-MEK-ERK cascades by immunohistochemistry in a series of 16 primary acral melanomas by tissue microarray. The expression of MAP kinase cascade proteins changed in most cases. The authors observed that 57.14% of cases were BRAF positive and that 61.53%, 71.42%, and 71.42% of cases were positive for MEK2, ERK1, and ERK2, respectively; RAS was not expressed in 92.31%, and all cases were negative for MEK1. The absence of RAS and positivity for MEK2, ERK1, and ERK2 were most seen in invasive cases with high thickness. These aspects of the MAPK pathway require further examination in acral melanomas between different populations. Nevertheless, the results highlight significant alterations in the MAP kinase cascades that are related to histological indicators of prognosis in primary acral melanomas.- Immunostaining study of cytokeratins in human hair follicle development(2020) SILVA, Laura Maria Andrade; HSIEH, Ricardo; LOURENCO, Silvia Vanessa; VALENTE, Neusa Yuriko Sakai; PAIVA, Geise Rezende; FERNANDES, Juliana DumetBackground: The hair follicle is a unique structure, one of the most dynamic structures in mammalians, which can reproduce in every new cycle all the mechanism involved in its fetal development. Although a lot of research has been made about the human hair follicle much less has been discovered about the importance of the cytokeratins (CKs) in its development. Objective: Study the immunohistochemical pattern of epithelial CKs during human hair follicle development. Methods: We performed an immunohistochemical study using fresh post-mortem skin biopsies of human fetuses between 4 and 25 weeks of gestational age to study the expression of cytokeratins (CKs): CK1, CK10, CK13, CK14, CK16 and CK20 during human hair follicle fetal development. Study limitations: Restrospective study with a good number of makers but with a small population. Results/conclusion: We found that, the CKs were expressed in an intermediate time during follicular development. The epithelial CKs (CK1, CK14, CK10, CK13) and the epithelial CKs witha proliferative character such as CK16 were expressed first, as markers of cellular maturation and follicular keratinization. At a later phase, CK20 was expressed in more developed primitive hair follicles as previously discussed in literature. (C) 2020 Sociedade Brasileira de Dermatologia.
- Metastasis to the Oral Cavity: Report of 12 Cases(2022) V, Silvia Lourenco; FLOREZI, Giovanna P.; SMITTER, Anabel S.; BOLOGNA, Sheyla B.; NICO, Marcello M. S.Oral cavity is not a common route for metastatic dissemination; metastasis to the oral region may affect soft tissues and jawbones, accounting for approximately 1% of all oral malignant neoplasms. The diagnosis of metastatic lesions to the oral cavity is usually challenging to clinicians and pathologists because of their complexity and rarity. We present a series of 12 metastatic neoplasms to the oral cavity that were detected previously or after the diagnosis of the primary tumor. All tumors were of epithelial origin with primary sites in the esophagus (2 cases), colon (2 cases), bladder, lungs, liver, larynx, skin, uterus, prostate, and adrenal gland, each with one case. The commonest site of the metastatic masses in the oral cavity was the gingiva, frequently presented as a vegetating, friable mass. The clinical examination and histopathologic analysis of the lesions were central to establishing the final diagnosis of the tumors. Metastatic masses to the oral cavity should always be considered as differential diagnosis of benign-looking lesions, especially in patients with previous history of a malignant disease. Biopsy is mandatory to establish an accurate diagnosis.
- The CDKN2A and MAP Kinase Pathways: Molecular Roads to Primary Oral Mucosal Melanoma(2013) HSIEH, Ricardo; NICO, Marcello M. S.; COUTINHO-CAMILLO, Claudia M.; BUIM, Marcilei E.; SANGUEZA, Martin; LOURENCO, Silvia V.The etiology and pathogenesis of oral mucosal melanomas are poorly understood, and no intraoral risk factors have been identified. Recent studies have postulated that DNA repair mechanisms and cell growth pathways are involved in the development of melanoma-particularly changes in the CDKN2A (p16-cyclinD-Cdk-pRb) and MAPK pathways (RAS, BRAF, MEK 1/2, and ERK 1/2 proteins). We examined the central components of the CDKN2A and RAS-RAF-MEK-ERK cascades by immunohistochemistry in a series of 35 primary oral melanomas by tissue microarray (TMA). We noted altered expression of the CDKN2A cascade proteins, although these modulations did not correlate significantly with clinical and pathological parameters. The expression of MAP kinase cascade proteins changed in most cases. We observed that 28.57% of cases were RAS-positive and that 82.85% and 74.28% of cases were positive for BRAF and ERK2, respectively; MEK2 and ERK1 were not expressed in 48.57% and 80% of cases, and all cases were negative for MEK1. The absence of RAS and ERK1 and positivity for BRAF and ERK2 were associated with higher histological grade, vascular invasion, and metastasis. Expression of MEK2 was significantly linked to vascular invasion (P = 0.043). The CDKN2A and MAPK pathways require further study in mucosal melanomas, but our results highlight the significance of important alterations, particularly with regard to histological indicators of poor prognosis in primary oral mucosal melanomas, independent of UV exposure.
article Oral lichen planus(2011) NICO, Marcello Menta Simonsen; FERNANDES, Juliana Dumet; LOURENCO, Silvia VanessaOral lichen planus (OLP) is a relatively common mucosal disease that can present isolated or associated with cutaneous lichen planus. Contrarily to its cutaneous counterpart, though, OLP tends to be chronic, relapsing, and difficult to treat. Severe morbidity is related to erosive forms, and more aggressive presentations have been described, such as the ""gingivo-vulvar syndrome"". This article reviews the current knowledge about the pathogenesis, clinical picture, differential and laboratorial diagnosis, prognosis, and treatment of OLP.- Reflectance confocal microscopy (RCM)-based criteria for progression of lower-lip squamous cell carcinoma: A prospective study(2022) FERREIRA, Paula Silva; ROCHA, Lilian; BEZERRA, Ana Patricia Carneiro; NICO, Marcello Menta Simonsen; LOURENCO, Silvia VanessaBackground: Actinic cheilitis (AC) presents as a diffuse clinical-histopathological alteration throughout the lower lip. Objectives: To analyze AC lesions using reflectance confocal microscopy (RCM) and evaluate criteria for the early diagnosis of incipient squamous cell carcinoma (SCC). Methods: This prospective study comprised cases of clinically diagnosed AC. RCM was performed over the entire extension of the lower lip. The sites that showed the highest degree of morphological alteration by RCM, according to established criteria for AC and SCC, were biopsied. The RCM findings and histopathology were correlated to establish the precise and early diagnosis of SCC. Results: A total of 61 cases that had been clinically diagnosed with AC were included. The RCM findings that correlated independently with SCC were: nonedged papillae (sensitivity 84% and specificity 88%, p < 0.0001, and OR 42), cell-filled papillae (sensitivity 82% and specificity 93%, p < 0.0001, and OR 71.3), inflammation (sensitivity 68% and specificity 68%, p = 0.0163, and OR 4.8), large and roundish cells in the lamina propria (sensitivity 65% and specificity 100%, p < 0.0001, and OR infinity), and nests in the lamina propria (sensitivity 54% and specificity 100%, p < 0.0001, and OR infinity). An independent histopathological analysis classified the cases as partial epithelial dysplasia (25 cases, 41%) and SCC (36, 59%), and in 57 cases (94%), the results agreed with the categorization that was rendered by the RCM exam. Conclusions: RCM can be used to monitor AC cases, guide the biopsy site, and identify the early progression of AC to SCC with good sensitivity and specificity.
- Extraordinary Case: Unique Presentation of an Aggressive Epstein-Barr Virus-Positive Mucocutaneous Ulcer(2022) MIYASHIRO, Denis; NICO, Marcello Menta S.; ANG, Patricia Lin; SIQUEIRA, Sheila Aparecida Coelho; PEREIRA, Juliana; SANCHES, Jose Antonio; LOURENCO, Silvia VanessaEpstein-Barr virus-positive mucocutaneous ulcer is a recent and unusual type of lymphoproliferation, mostly associated with various forms of immunosuppression. In most cases, they regress spontaneously, but an increasing number of reports describe a spectral behavior of the lesion, which ranges from a simple ulcer with eosinophilia to aggressive ulcers. In these cases, Epstein-Barr virus-related lymphomas are the main differential diagnosis. We report a unique observation of this rare disease with mandibular involvement. Due to bone erosion, the patient was treated with 6 cycles of R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone) with complete healing of the ulcer on clinical examination and PET-scan control.
- 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.
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