LUCIANA PINTO BRITO
Projetos de Pesquisa
Unidades Organizacionais
Instituto Central, Hospital das Clínicas, Faculdade de Medicina - Médico
LIM/42 - Laboratório de Hormônios e Genética Molecular, Hospital das Clínicas, Faculdade de Medicina
LIM/42 - Laboratório de Hormônios e Genética Molecular, Hospital das Clínicas, Faculdade de Medicina
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- PROP1 and CTNNB1 expression in adamantinomatous craniopharyngiomas with or without beta-catenin mutations(2011) CANI, Carolina M. G.; MATUSHITA, Hamilton; CARVALHO, Luciani R. S.; SOARES, Ibere C.; BRITO, Luciana P.; ALMEIDA, Madson Q.; MENDONCA, Berenice B.INTRODUCTION: Activating mutations in exon 3 of the beta-catenin gene are involved in the pathogenesis of adamantinomatous craniopharyngiomas. Recently, the interaction between beta-catenin and PROP1 has been shown to be responsible for pituitary cell lineage determination. We hypothesized that dysregulated PROP1 expression could also be involved in the pathogenesis of craniopharyngiomas. OBJECTIVES: To determine whether dysregulated gene expression was responsible for tumor pathogenesis in adamantinomatous craniopharyngiomas, the beta-catenin gene was screened for mutations, and the expression of the beta-catenin gene and PROP1 was evaluated. METHODS: The beta-catenin gene was amplified and sequenced from 14 samples of adamantinomatous craniopharyngiomas. PROP1 and beta-catenin gene expression was assessed by real-time RT-PCR from 12 samples, and beta-catenin immunohistochemistry was performed on 11 samples. RESULTS: Mutations in the beta-catenin gene were identified in 64% of the adamantinomatous craniopharyngiomas samples. Evidence of beta-catenin gene overexpression was found in 71% of the tumors with beta-catenin mutations and in 40% of the tumors without mutations, and beta-catenin immunohistochemistry revealed a nuclear staining pattern for each of the analyzed samples. PROP1 expression was undetectable in all of the tumor samples. CONCLUSION: We found evidence of beta-catenin gene overexpression in the majority of adamantinomatous craniopharyngiomas, and we also detected a nuclear beta-catenin staining pattern regardless of the presence of a beta-catenin gene mutation. These results suggest that WNT signaling activation plays an important role in the pathogenesis of adamantinomatous craniopharyngiomas. Additionally, this study was the first to evaluate PROP1 expression in adamantinomatous craniopharyngiomas, and the absence of PROP1 expression indicates that this gene is not involved in the pathogenesis of this tumor, at least in this cohort.
article 9 Citação(ões) na Scopus Clinical and molecular aspects of a pediatric metachronous adrenocortical tumor(2011) LIMA, Lorena de Oliveira; LERARIO, Antonio Marcondes; ALENCAR, Guilherme Asmar; BRITO, Luciana Pinto; ALMEIDA, Madson Queiroz; DOMENICE, Sorahia; LATRONICO, Ana Claudia; MENDONCA, Berenice Bilharinho; FRAGOSO, Maria Candida Barrison VillaresThe occurrence of metachronous adrenocortical carcinoma has rarely been described. We report a case of a child with virilizing adrenocortical metachronous tumors that, despite several metastases, presented long-term survival (15 years). We analyzed in this tumor IGF2, IGF1R and FGFR4 gene expression, and evaluated the presence of p.R337H germline p53 mutation and somatic CTNNB1 mutation. IGF2 gene was over-expressed in both left (Weiss score 5) and right (Weiss 7) adrenocortical tumors. IGF1R expression levels were higher in the right adrenocortical tumor. FGFR4 over-expression was also detected in the right adrenocortical tumor. In addition, this patient harbors the germline p.R337H p53 mutation and loss of heterozygosity (LOH) was detected in the tumors. No somatic CTNNB1 mutations were found in both tumors. In conclusion, we demonstrated in this unusual case the over-expression of growth signaling pathways, which are molecular mechanisms previously related to adrenocortical tumorigenesis. Furthermore, the absence of somatic CTNNB1 mutations, which is a molecular marker of poor prognosis in adults, might be related to the long-term survival of this patient. Arq Bras Endocrinol Metab. 2011;55(1) 72-7- Increased expression of ACTH (MC2R) and androgen (AR) receptors in giant bilateral myelolipomas from patients with congenital adrenal hyperplasia(2014) ALMEIDA, Madson Q.; KAUPERT, Laura C.; BRITO, Luciana P.; LERARIO, Antonio M.; MARIANI, Beatriz M. P.; RIBEIRO, Marta; MONTE, Osmar; DENES, Francisco T.; MENDONCA, Berenice B.; BACHEGA, Tania A. S. S.Background: Although chronic adrenocorticotropic hormone (ACTH) and androgen hyperstimulation are assumed to be involved in the pathogenesis of adrenal myelolipomas associated with poor-compliance patients with congenital adrenal hyperplasia (CAH), the expression of their receptors has not yet been demonstrated in these tumors so far. Methods: We analyzed Melanocortin 2 receptor (MC2R), Androgen Receptor (AR), Leptin (LEP), and Steroidogenic factor 1 (SF1) expression using real-time qRT-PCR in two giant bilateral adrenal myelolipomas from two untreated simple virilizing CAH cases and in two sporadic adrenal myelolipomas. In addition, the X-chromosome inactivation pattern and CAG repeat numbers in AR exon 1 gene were evaluated in the 4 cases. Results: The MC2R gene was overexpressed in myelolipomas from 3 out of 4 patients. AR overexpression was detected in 2 tumors: a giant bilateral myelolipoma in a CAH patient and a sporadic case. Simultaneous overexpression of AR and MC2R genes was found in two of the cases. Interestingly, the bilateral giant myelolipoma associated with CAH that had high androgen and ACTH levels but lacked MC2R and AR overexpression presented a significantly shorter AR allele compared with other tumors. In addition, X-chromosome inactivation pattern analysis showed a polyclonal origin in all tumors, suggesting a stimulatory effect as the trigger for tumor development. Conclusion: These findings are the first evidence for MC2R or AR overexpression in giant bilateral myelolipomas from poor-compliance CAH patients.
- Efficacy of Oral Furosemide Test for Primary Aldosteronism Diagnosis(2023) FREITAS, Thais C.; MACIEL, Ana Alice W.; FAGUNDES, Gustavo F. C.; PETENUCI, Janaina; SANTANA, Lucas S.; GUIMARAES, Augusto G.; FREITAS-CASTRO, Felipe; SROUGI, Victor; TANNO, Fabio Y.; CHAMBO, Jose L.; PEREIRA, Maria Adelaide A.; BRITO, Luciana P.; PIO-ABREU, Andrea; BORTOLOTTO, Luiz A.; LATRONICO, Ana Claudia; V, Maria Candida B. Fragoso; DRAGER, Luciano F.; MENDONCA, Berenice B.; ALMEIDA, Madson Q.Context: Confirmatory tests represent a fundamental step in primary aldosteronism (PA) diagnosis, but they are laborious and often require a hospital environment due to the risks involved.Objective: To evaluate the efficacy of oral furosemide as a new confirmatory test for PA diagnosis.Methods: We prospectively evaluated the diagnostic performance of 80 mg of oral furosemide in 64 patients with PA and 22 with primary hypertension (controls). Direct renin concentration (DRC) was measured before, and 2 hours and 3 hours after the oral furosemide. In addition, the oral furosemide test was compared with 2 other confirmatory tests: the furosemide upright test (FUT) and saline infusion test (SIT) or captopril challenge test (CCT) in all patients with PA.Results: The cut-off of 7.6 mu U/mL for DRC at 2 hours after oral furosemide had a sensitivity of 92%, specificity of 82%, and accuracy of 90% for PA diagnosis. In 5 out of 6 controls with low-renin hypertension, which might represent a PA spectrum, renin remained suppressed. Excluding these 6 controls with low-renin hypertension, the DRC cut-off of 10 mu U/mL at 2 hours after oral furosemide had a sensitivity of 95.3%, specificity of 93.7% and accuracy of 95% for PA diagnosis. DRC after 3 hours of oral furosemide did not improve diagnostic performance. Using the cut-off of 10 mu U/mL, the oral furosemide test and the FUT were concordant in 62 out of 64 (97%) patients with PA. Only 4 out of 64 cases with PA (6.4%) ended the oral furosemide test with potassium <3.5 mEq/L. Hypotension was not evidenced in any patient with PA during the test.Conclusion: The oral furosemide test was safe, well-tolerated and represents an effective strategy for PA investigation.