RICARDO HSIEH
Projetos de Pesquisa
Unidades Organizacionais
Departamento de Dermatologia, Faculdade de Medicina
LIM/06 - Laboratório de Imunopatologia da Esquistossomose e outras Parasitoses, Hospital das Clínicas, Faculdade de Medicina
LIM/06 - Laboratório de Imunopatologia da Esquistossomose e outras Parasitoses, Hospital das Clínicas, Faculdade de Medicina
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Resultados de Busca
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- Immunoexpression of adhesion molecules during human fetal hair development(2020) SILVA, Laura Maria Andrade; HSIEH, Ricardo; LOURENCO, Silvia Vanessa; OTTONI, Veronica; VALENTE, Neusa; FERNANDES, Juliana DumetIntroduction. Hair follicles are produced in a cyclical manner and the machinery involved in the reproduction of these follicles is present since the fetal stage. Although extensive research has been done on the human hair follicle, very little is known about the importance of adhesion molecules in its development. Material and methods. We analyzed here, the immunoexpression of beta-1 integrin, p-cadherin, e-cadherin, and beta-catenin in hair follicles from 26 formalin-fixed and paraffin-embedded skin samples from human embryos and fetus between 12-23 weeks of gestational age. Results. The adhesion molecules beta-1 integrin and e-cadherin/p-cadherin were expressed from 12 weeks and seemed to play a role in regulating epidermis invagination. Beta-catenin immunostaining was negative in all cases; down regulation of this protein may be necessary for fetal hair development and thus facilitating hair follicle down growth. Discussion/Conclusion. Adhesion molecules are essential for hair follicle down growth and proliferation; integrins and cadherins play a major role in this process. More studies are needed to describe hair follicle development.
- 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.
- Epithelial-mesenchymal transition related to bone invasion in oral squamous cell carcinoma(2022) VANINI, Jaqueline Vaz; KOYAMA, Leonardo Kenji Sakaue; MATOS, Leandro Luongo de; FIGUEREDO JUNIOR, Jose Martins; CERNEA, Claudio Roberto; NAGANO, Cibele Pidorodeski; COUTINHO-CAMILLO, Claudia Malheiros; HSIEH, Ricardo; LOURENCO, Silvia VanessaIntroduction: Bone invasion is an important prognostic factor in oral squamous cell carcinoma, leading to a lower survival rate and the use of aggressive treatment approaches. Epithelial-mesenchymal transition (EMT) is possibly involved in this process, because it is often related to mechanisms of cell motility and invasiveness. This study examined whether a panel of epithelial-mesenchymal markers are present in cases of oral squamous cell carcinoma with bone invasion and whether these proteins have any relationship with patients' clinical-pathological parameters and prognostic factors. Methods: Immunohistochemical analysis of E-cadherin, twist, vimentin, TGF beta 1, and periostin was performed in paraffin-embedded samples of 62 oral squamous cell carcinoma cases. Results: The analysis revealed that most cases (66%) presented with a dominant tumor infiltrative pattern in bone tissue, associated with lower survival rates, when compared with cases with a dominant erosive invasion pattern (P = 0.048). Twenty-seven cases (43%) expressed markers that were compatible with total or partial EMT at the tumor-bone interface. There was no association between evidence of total or partial EMT and other demographic or prognostic features. E-cadherin-positive cases were associated with tobacco smoking (P = 0.022); vimentin-positive cases correlated with tumors under 4 cm (P = 0.043). Twistexpression was observed in tumors with a dominant infiltrative pattern (P = 0.041) and was associated with the absence of periostin (P = 0.031). Conclusion: We observed evidence of total or partial EMT in oral squamous cell carcinoma bone invasion. The transcription factor twist appears to be involved in bone invasion and disease progression. (C) 2022 The Authors.
- 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.