MARIA MITZI BRENTANI
Projetos de Pesquisa
Unidades Organizacionais
Departamento de Radiologia, Faculdade de Medicina - Docente
LIM/24 - Laboratório de Oncologia Experimental, Hospital das Clínicas, Faculdade de Medicina - Líder
LIM/05 - Laboratório de Poluição Atmosférica Experimental, Hospital das Clínicas, Faculdade de Medicina
LIM/24 - Laboratório de Oncologia Experimental, Hospital das Clínicas, Faculdade de Medicina - Líder
LIM/05 - Laboratório de Poluição Atmosférica Experimental, Hospital das Clínicas, Faculdade de Medicina
8 resultados
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- Comprehensive Analysis of BRCA1, BRCA2 and TP53 Germline Mutation and Tumor Characterization: A Portrait of Early-Onset Breast Cancer in Brazil(2013) CARRARO, Dirce Maria; FOLGUEIRA, Maria Aparecida Azevedo Koike; LISBOA, Bianca Cristina Garcia; OLIVIERI, Eloisa Helena Ribeiro; KREPISCHI, Ana Cristina Vitorino; CARVALHO, Alex Fiorini de; MOTA, Louise Danielle de Carvalho; PUGA, Renato David; MACIEL, Maria do Socorro; MICHELLI, Rodrigo Augusto Depieri; LYRA, Eduardo Carneiro de; GROSSO, Stana Helena Giorgi; SOARES, Fernando Augusto; ACHATZ, Maria Isabel Alves de Souza Waddington; BRENTANI, Helena; MOREIRA-FILHO, Carlos Alberto; BRENTANI, Maria MitziGermline mutations in BRCA1, BRCA2 and TP53 genes have been identified as one of the most important disease-causing issues in young breast cancer patients worldwide. The specific defective biological processes that trigger germline mutation-associated and -negative tumors remain unclear. To delineate an initial portrait of Brazilian early-onset breast cancer, we performed an investigation combining both germline and tumor analysis. Germline screening of the BRCA1, BRCA2, CHEK2 (c.1100delC) and TP53 genes was performed in 54 unrelated patients <35 y; their tumors were investigated with respect to transcriptional and genomic profiles as well as hormonal receptors and HER2 expression/amplification. Germline mutations were detected in 12 out of 54 patients (22%) [7 in BRCA1 (13%), 4 in BRCA2 (7%) and one in TP53 (2%) gene]. A cancer familial history was present in 31.4% of the unrelated patients, from them 43.7% were carriers for germline mutation (37.5% in BRCA1 and in 6.2% in the BRCA2 genes). Fifty percent of the unrelated patients with hormone receptor-negative tumors carried BRCA1 mutations, percentage increasing to 83% in cases with familial history of cancer. Over-representation of DNA damage-, cellular and cell cycle-related processes was detected in the up-regulated genes of BRCA1/2-associated tumors, whereas cell and embryo development-related processes were over-represented in the up-regulated genes of BRCA1/2-negative tumors, suggesting distinct mechanisms driving the tumorigenesis. An initial portrait of the early-onset breast cancer patients in Brazil was generated pointing out that hormone receptor-negative tumors and positive familial history are two major risk factors for detection of a BRCA1 germline mutation. Additionally, the data revealed molecular factors that potentially trigger the tumor development in young patients.
- Breast cancer tissue slices as a model for evaluation of response to rapamycin(2013) GROSSO, Stana Helena Giorgi; KATAYAMA, Maria Lucia Hirata; ROELA, Rosimeire Aparecida; NONOGAKI, Suely; SOARES, Fernando Augusto; BRENTANI, Helena; LIMA, Leandro; FOLGUEIRA, Maria Aparecida Azevedo Koike; WAITZBERG, Angela Flavia Logullo; PASINI, Faima Solange; GOES, Joao Carlos Guedes Sampaio; BRENTANI, M. MitziRapamycin is a selective inhibitor of the mammalian target of rapamycin (mTOR), a regulator kinase that integrates growth factors signaling via the phosphoinositide-3-kinase pathway and that has emerged as a novel therapeutic modality in breast cancer (BC). We propose a pre-clinical ""ex-vivo"" personalized organotypic culture of BC that preserves the microenvironment to evaluate rapamycin-mediated gene expression changes. Freshly excised ductal invasive BC slices, 400 mu m thick (n=30), were cultured in the presence or absence (control) of rapamycin (20 nM) for 24 h. Some slices were formalin-fixed for immunohistochemical determinations and some were processed for microarray analysis. Control slices in culture retained their tissue morphology and tissue viability (detected by BrdU uptake). The percentage of proliferating cells (assessed by Ki67) did not change up to 24 h of treatment. Immunohistochemical evaluation of p-AKT, p-mTOR, p-4EBP1 and p-S6K1 indicated that AKT/mTOR pathway activation was maintained during cultivation. For microarray analysis, slices were divided into two groups, according to the presence/absence of epidermal growth factor receptor-type 2 and analyzed separately. Limited overlap was seen among differentially expressed genes after treatment (P < 0.01) in both groups suggesting different responses to rapamycin between these BC subtypes. Ontology analysis indicated that genes involved in biosynthetic processes were commonly reduced by rapamycin. Our network analysis suggested that concerted expression of these genes might distinguish controls from treated slices. Thus, breast carcinoma slices constitute a suitable physiological tool to evaluate the short-term effects of rapamycin on the gene profile of individual BC samples.
conferenceObject BASELINE STAGING TESTS FOR LOCALLY ADVANCED BREAST CANCER(2013) VIEIRA, R. A. C.; GARCIA, G. F.; ZUCCA-MATTHES, A. G.; UEMURA, G.; BRENTANI, M. M.; FOLGUEIRA, M. A. A. K.Goals: To evaluate the impact of different radiological exams in the clinical staging of locally advanced breast cancer (LABC) and the possibility to evaluate bone metastasis with computed tomography (CT) in substitution of scintigraphy. Methods: A prospective clinical trial (www.clinicaltrials.gov; NCT00820690) performed in breast cancer women during 06/2008 to 05/2011. Patients with invasive carcinoma, clinical stage III, absence of systemic symptoms and absence of previous treatment were included. Exclusion criteria were the absence of invasive disease, staging exams and follow-up. The patients were submitted to a clinical examination, mammography, breast ultrasound and biopsy. To evaluate the presence of metastatic disease the patients were submitted to chest X-Ray, abdominal ultrasound, bone scintigraphy (conventional exams) and CT (abdominal and thoracic). In the presence of suspicion exams, complementary exams were performed. If the CT needs control, new exams were performed. All patients were submitted to neoadjuvant or palliative chemotherapy. At the end of study one radiologist reviewed all exams and medical reports. We evaluated the frequency of metastasis in the conventional exams and when the patients were evaluated with CT. Results: 148 patients were enrolled, but 10 patients were excluded. From the 138 patients, the median tumor size was 6.6cm (3–15cm). Evaluating the clinical stage (TNM) there were 60.9% cT3, 38.4% cT4, 67.4% cN1, 25.4% cN2 and 2.2% cN3. After all exams performed 38 (28.3%) had metastatic disease. When we use conventional exams8.7%hadmetastaticdisease,but17.4%neededcomplementary exams, leading to 13.8% [IC=8.08–19.55] of metastatic disease. When we use CT (abdominal and thoracic) and scintigraphy for staging, 28.3% [IC=20.8–34.9] had metastatic disease, with an increase of 14.5% of diagnosis of metastatic disease. The CT showed 6 patients (4.3%) with bone metastasis and normal scintigraphy, but it did not increased the frequency of metastatic disease. Conclusion: Patients with LABC must be evaluated with a minimum of CT (abdominal and thoracic) added to the bone scintigraphy. The conventional exams decreased 14.5% of the metastatic disease diagnosis and the CT increased 4.3% of diagnosis of bone metastasis. Disclosure of Interest: No significant relationships.- Markers of breast cancer stromal fibroblasts in the primary tumour site associated with lymph node metastasis: a systematic review including our case series(2013) FOLGUEIRA, Maria Aparecida Azevedo Koike; MAISTRO, Simone; KATAYAMA, Maria Lucia Hirata; ROELA, Rosimeire Aparecida; MUNDIM, Fiorita Gonzales Lopes; NANOGAKI, Suely; BOCK, Geertruida H. de; BRENTANI, M. MitziCAFs (cancer-associated fibroblasts), the most abundant cell type in breast cancer stroma, produce a plethora of chemokines, growth factors and ECM (extracellular matrix) proteins, that may contribute to dissemination and metastasis. Axillary nodes are the first metastatic site in breast cancer; however, to the present date, there is no consensus of which specific proteins, synthesized by CAFs, might be related with lymph node involvement. The purpose of this study was to perform a systematic review of CAF biomarkers associated with the presence of regional metastasis. PubMed was searched using the words: 'breast cancer' and 'lymph node' and fibroblast or stroma or microenvironment. After exclusions, eight studies evaluating biomarkers immunoexpression in CAFs and lymph node status were selected. Biomarkers evaluated in these studies may be divided in two groups, according to their ontology: extracellular matrix components [MMP13 (matrix metalloproteinase 13), TIMP2 (tissue inhibitor of metalloproteinases-2), THBS1 (thrombospondin 1), LGALS1 (lectin, galactoside-binding, soluble, 1)] and response to wounding [PDPN (podoplanin), PLAU (plasminogen activator, urokinase), PLAUR (plasminogen activator, urokinase receptor), CAV1 (caveolin 1), THBS1, LGALS1]. A positive expression of MMP13 and LGALS1 in CAFs was associated with enhanced OR (odds ratio) for regional metastasis. Contrariwise, CAV1 positive staining of fibroblasts was associated with decreased OR for nodal involvement. Expression of MMP13, PDPN and CAV1 was further tested in a new series of 65 samples of invasive ductal breast carcinomas by immunohistochemistry and no association between biomarkers expression in CAFs and nodal status was found. It was suggested that breast cancer subtypes may differentially affect CAFs behaviour. It would be interesting to evaluate the prognostic significance of these biomarkers in CAFs from different tumour types.
- Differences in transcriptional effects of 1 alpha,25 dihydroxyvitamin D3 on fibroblasts associated to breast carcinomas and from paired normal breast tissues(2013) CAMPOS, Laura Tojeiro; BRENTANI, Helena; ROELA, Rosimeire Aparecida; KATAYAMA, Maria Lucia Hirata; LIMA, Leandro; ROLIM, Cintia Flores; MILANI, Cintia; FOLGUEIRA, Maria Aparecida Azevedo Koike; BRENTANI, Maria MitziThe effects of 1 alpha,25 dihydroxyvitamin D3 (1,25D) on breast carcinoma associated fibroblasts (CAFs) are still unknown. This study aimed to identify genes whose expression was altered after 1,25D treatment in CAFs and matched adjacent normal mammary associated fibroblasts (NAFs). CAFs and NAFs (from 5 patients) were cultured with or without (control) 1,25D 100 nM. Both CAF and NAF expressed vitamin D receptor (VDR) and 1,25D induction of the genomic pathway was detected through up-regulation of the target gene CYP24A1. Microarray analysis showed that despite presenting 50% of overlapping genes, CAFs and NAFs exhibited distinct transcriptional profiles after 1,25D treatment (FDR <0.05). Functional analysis revealed that in CAFs, genes associated with proliferation (NRG1, WNT5A, PDGFC) were down regulated and those involved in immune modulation (NFKBIA, TREM-1) were up regulated, consistent with anti tumor activities of 1,25D in breast cancer. In NAFs, a distinct subset of genes was induced by 1,25D, involved in anti apoptosis, detoxification, antibacterial defense system and protection against oxidative stress, which may limit carcinogenesis. Co-expression network and interactome analysis of genes commonly regulated by 1,25D in NAFs and CAFs revealed differences in their co-expression values, suggesting that 1,25D effects in NAFs are distinct from those triggered in CAFs.
- Transcriptional effects of 1,25 dihydroxyvitamin D-3 physiological and supra-physiological concentrations in breast cancer organotypic culture(2013) MILANI, Cintia; KATAYAMA, Maria Lucia Hirata; LYRA, Eduardo Carneiro de; WELSH, JoEllen; CAMPOS, Laura Tojeiro; BRENTANI, M. Mitzi; MACIEL, Maria do Socorro; ROELA, Rosimeire Aparecida; VALLE, Paulo Roberto del; GOES, Joao Carlos Guedes Sampaio; NONOGAKI, Suely; TAMURA, Rodrigo Esaki; FOLGUEIRA, Maria Aparecida Azevedo KoikeBackground: Vitamin D transcriptional effects were linked to tumor growth control, however, the hormone targets were determined in cell cultures exposed to supra physiological concentrations of 1,25(OH)(2)D-3 (50-100nM). Our aim was to evaluate the transcriptional effects of 1,25(OH)(2)D-3 in a more physiological model of breast cancer, consisting of fresh tumor slices exposed to 1,25(OH)(2)D-3 at concentrations that can be attained in vivo. Methods: Tumor samples from post-menopausal breast cancer patients were sliced and cultured for 24 hours with or without 1,25(OH)(2)D-3 0.5nM or 100nM. Gene expression was analyzed by microarray (SAM paired analysis, FDR <= 0.1) or RT-qPCR (p <= 0.05, Friedman/Wilcoxon test). Expression of candidate genes was then evaluated in mammary epithelial/breast cancer lineages and cancer associated fibroblasts (CAFs), exposed or not to 1,25(OH)(2)D-3 0.5nM, using RT-qPCR, western blot or immunocytochemistry. Results: 1,25(OH)(2)D-3 0.5nM or 100nM effects were evaluated in five tumor samples by microarray and seven and 136 genes, respectively, were up-regulated. There was an enrichment of genes containing transcription factor binding sites for the vitamin D receptor (VDR) in samples exposed to 1,25(OH)(2)D-3 near physiological concentration. Genes up-modulated by both 1,25(OH)(2)D-3 concentrations were CYP24A1, DPP4, CA2, EFTUD1, TKTL1, KCNK3. Expression of candidate genes was subsequently evaluated in another 16 samples by RT-qPCR and up-regulation of CYP24A1, DPP4 and CA2 by 1,25(OH)(2)D-3 was confirmed. To evaluate whether the transcripitonal targets of 1,25(OH)(2)D-3 0.5nM were restricted to the epithelial or stromal compartments, gene expression was examined in HB4A, C5.4, SKBR3, MDA-MB231, MCF-7 lineages and CAFs, using RT-qPCR. In epithelial cells, there was a clear induction of CYP24A1, CA2, CD14 and IL1RL1. In fibroblasts, in addition to CYP24A1 induction, there was a trend towards up-regulation of CA2, IL1RL1, and DPP4. A higher protein expression of CD14 in epithelial cells and CA2 and DPP4 in CAFs exposed to 1,25(OH)(2)D-3 0.5nM was detected. (Continued on next page) (Continued from previous page) Conclusions: In breast cancer specimens a short period of 1,25(OH)(2)D-3 exposure at near physiological concentration modestly activates the hormone transcriptional pathway. Induction of CYP24A1, CA2, DPP4, IL1RL1 expression appears to reflect 1,25(OH)(2)D-3 effects in epithelial as well as stromal cells, however, induction of CD14 expression is likely restricted to the epithelial compartment.
- Lipid raft disruption by docosahexaenoic acid induces apoptosis in transformed human mammary luminal epithelial cells harboring HER-2 overexpression(2013) RAVACCI, Graziela Rosa; BRENTANI, Maria Mitzi; TORTELLI JR., Tharcisio; TORRINHAS, Raquel Suzana M. M.; SALDANHA, Tatiana; TORRES, Elizabeth Aparecida F. S.; WAITZBERG, Dan LinetzkyIn HER-2-overexpressing breast cells, HER-2 receptors exist on the cell surface as monomers, homodimers and heterodimers. For signal activation and transduction to occur, HER-2 must be localized to lipid rafts. Therefore, we hypothesized that the amount of lipid rafts on the cell membrane would be a factor in HER-2 signaling. To test this, we used HB4a (an untransformed human mammary epithelial cell line) and HB4aC5.2 cells. HB4aC5.2 cells are HB4a derivatives that have been transfected with five copies of pJ5E.c-ErbB-2 and express approximately 900 times more HER-2 than HB4a cells. In these cells, HER-2 overexpression was accompanied by increased lipid rafts in cell membranes, a hyperactivation of downstream Akt and ERK1/2 proteins, and an increased rate of cell growth compared to HB4a. In addition, HER-2 overexpression was associated with an increased activation of FASN, a key enzyme involved in cellular lipogenesis. Its final product, palmitate, is frequently used to synthesize lipid rafts. We further hypothesized that treatment with docosahexaenoic acid (DHA), an omega-3 fatty acid, would disrupt the lipid rafts and lead to a growth arrest In HB4aC5.2 cells, but not HB4a cells, we found that DHA treatment disrupted lipid raft; inhibited HER-2 signaling by decreasing activation of Akt, ERK1/2 and FASN proteins; and induced apoptosis. Although little is known about lipid rafts, our data support the idea that disturbances in these microdomains induced by DHA may represent a useful tool for controlling the signaling initiated by HER-2 receptors and its therapeutic potential in the treatment of HER-2 positive breast cancer.
- Characterization of risk factors in breast cancer young adult patients(2013) ENCINAS, G.; DIZ, M. D. P. E.; LYRA, E. C.; KATAYAMA, M. L. H.; PASINI, F. S.; BRENTANI, M. M.; CHAMMAS, R.; GOES, J. C. G. S.; FOLGUEIRA, M. A. A. K.