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
11 resultados
Resultados de Busca
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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.
- Gene Expression Profile in Response to Doxorubicin-Rapamycin Combined Treatment of HER-2-Overexpressing Human Mammary Epithelial Cell Lines(2012) TRAPE, Adriana Priscila; KATAYAMA, Maria Lucia Hirata; ROELA, Rosimeire Aparecida; BRENTANI, Helena; RAVACCI, Graziela Rosa; LIMA, Leandro de Araujo; BRENTANI, Maria MitziHER-2-positive breast cancers frequently sustain elevated AKT/mTOR signaling, which has been associated with resistance to doxorubicin treatment. Here, we investigated whether rapamycin, an mTOR inhibitor, increased the sensitivity to doxorubicin therapy in two HER-2-overexpressing cell lines: C5.2, which was derived from the parental HB4a by transfection with HER-2 and SKBR3, which exhibits HER-2 amplification. The epithelial mammary cell line HB4a was also analyzed. The combined treatment using 20 nmol/L of rapamycin and 30 nmol/L of doxorubicin arrested HB4a and C5.2 cells in S to G(2)-M, whereas SKBR3 cells showed an increase in the G(0)-G(1) phase. Rapamycin increased the sensitivity to doxorubicin in HER-2-overexpressing cells by approximately 2-fold, suggesting that the combination displayed a more effective antiproliferative action. Gene expression profiling showed that these results might reflect alterations in genes involved in canonical pathways related to purine metabolism, oxidative phosphorylation, protein ubiquitination, and mitochondrial dysfunction. A set of 122 genes modulated by the combined treatment and specifically related to HER-2 overexpression was determined by finding genes commonly regulated in both C5.2 and SKBR3 that were not affected in HB4a cells. Network analysis of this particular set showed a smaller subgroup of genes in which coexpression pattern in HB4a cells was disrupted in C5.2 and SKBR3. Altogether, our data showed a subset of genes that might be more robust than individual markers in predicting the response of HER-2-overexpressing breast cancers to doxorubicin and rapamycin combination.
- 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.
- MicroRNAs Discriminate Familial from Sporadic Non-BRCA1/2 Breast Carcinoma Arising in Patients <= 35 Years(2014) BASTOS, Elen Pereira; BRENTANI, Helena; PASINI, Fatima Solange; SILVA, Aderbal Ruy T.; TORRES, Cesar Henrique; PUGA, Renato David; OLIVIERI, Eloisa Helena Ribeiro; PIOVEZANI, Amanda Rusiska; PEREIRA, Carlos Alberto de Braganca; MACHADO-LIMA, Ariane; CARRARO, Dirce Maria; BRENTANI, Maria MitziThe influence of genetic factors may contribute to the poor prognosis of breast cancer (BC) at a very young age. However BRCA1/2 mutations could not explain the majority of cases arising in these patients. MicroRNAs (miRs) have been implicated in biological processes associated with BC. Therefore, we investigated differences in miRs expression between tumors from young patients (<= 35 years) with sporadic or familial history and non-carriers of BRCA1/2 mutations. Thirty-six young Brazilian patients were divided into 2 groups: sporadic (NF-BC) or familial breast cancer (F-BC). Most of the samples were classified as luminal A and B and the frequency of subtypes did not differ between familial or sporadic cases. Using real time qPCR and discriminant function analysis, we identified 9 miRs whose expression levels rather than miR identity can discriminate between both patient groups. Candidate predicted targets were determined by combining results from miRWalk algorithms with mRNA expression profiles (n = 91 differently expressed genes). MiR/mRNA integrated analysis identified 91 candidate genes showing positive or negative correlation to at least 1 of the 9 miRs. Co-expression analysis of these genes with 9 miRs indicated that 49 differentially co-expressed miR-gene interactions changes in F-BC tumors as compared to those of NF-BC tumors. Out of 49, 17 (34.6%) of predicted miR-gene interactions showed an inverse correlation suggesting that miRs act as post-transcriptional regulators, whereas 14 (28.6%) miR-gene pairs tended to be co-expressed in the same direction indicating that the effects exerted by these miRs pointed to a complex level of target regulation. The remaining 18 pairs were not predicted by our criteria suggesting involvement of other regulators. MiR-mRNA co-expression analysis allowed us to identify changes in the miR-mRNA regulation that were able to distinguish tumors from familial and sporadic young BC patients non-carriers of BRCA mutations.
- Specific upregulation of RHOA and RAC1 in cancer-associated fibroblasts found at primary tumor and lymph node metastatic sites in breast cancer(2015) ROZENCHAN, Patricia Bortman; PASINI, Fatima Solange; ROELA, Rosimeire A.; KATAYAMA, Maria Lucia Hirata; MUNDIM, Fiorita Gonzales Lopes; BRENTANI, Helena; LYRA, Eduardo C.; BRENTANI, Maria MitziThe importance of tumor-stromal cell interactions in breast tumor progression and invasion is well established. Here, an evaluation of differential genomic profiles of carcinoma-associated fibroblasts (CAFs) compared to fibroblasts derived from tissues adjacent to fibroadenomas (NAFs) revealed altered focal adhesion pathways. These data were validated through confocal assays. To verify the possible role of fibroblasts in lymph node invasion, we constructed a tissue microarray consisting of primary breast cancer samples and corresponding lymph node metastasis and compared the expression of adhesion markers RhoA and Rac1 in fibroblasts located at these different locations. Two distinct tissue microarrays were constructed from the stromal component of 43 primary tumors and matched lymph node samples, respectively. Fibroblasts were characterized for their expression of alpha-smooth muscle actin (alpha-SMA) and vimentin. Moreover, we verified the level of these proteins in the stromal compartment from normal adjacent tissue and in non-compromised lymph nodes. Our immunohistochemistry revealed that 59 % of fibroblasts associated with primary tumors and 41 % of the respective metastatic lymph nodes (p = 0.271) displayed positive staining for RhoA. In line with this, 57.1 % of fibroblasts associated with primary tumors presented Rac1-positive staining, and the frequency of co-positivity within the lymph nodes was 42.9 % (p = 0.16). Expression of RhoA and Rac1 was absent in fibroblasts of adjacent normal tissue and in compromised lymph nodes. Based on our findings that no significant changes were observed between primary and metastatic lymph nodes, we suggest that fibroblasts are active participants in the invasion of cancer cells to lymph nodes and support the hypothesis that metastatic tumor cells continue to depend on their microenvironment.
- Poly (A)(+) Transcriptome Assessment of ERBB2-Induced Alterations in Breast Cell Lines(2011) CARRARO, Dirce Maria; FERREIRA, Elisa Napolitano; MOLINA, Gustavo de Campos; PUGA, Renato David; ABRANTES, Eduardo Fernandes; TRAPE, Adriana Priscila; EKHARDT, Bedrich L.; NUNES, Diana Noronha; BRENTANI, Maria Mitzi; ARAP, Wadih; PASQUALINI, Renata; BRENTANI, Helena; DIAS-NETO, Emmanuel; BRENTANI, Ricardo RenzoWe report the first quantitative and qualitative analysis of the poly (A)(+) transcriptome of two human mammary cell lines, differentially expressing (human epidermal growth factor receptor) an oncogene over-expressed in approximately 25% of human breast tumors. Full-length cDNA populations from the two cell lines were digested enzymatically, individually tagged according to a customized method for library construction, and simultaneously sequenced by the use of the Titanium 454-Roche-platform. Comprehensive bioinformatics analysis followed by experimental validation confirmed novel genes, splicing variants, single nucleotide polymorphisms, and gene fusions indicated by RNA-seq data from both samples. Moreover, comparative analysis showed enrichment in alternative events, especially in the exon usage category, in ERBB2 over-expressing cells, data indicating regulation of alternative splicing mediated by the oncogene. Alterations in expression levels of genes, such as LOX, ATP5L, GALNT3, and MME revealed by large-scale sequencing were confirmed between cell lines as well as in tumor specimens with different ERBB2 backgrounds. This approach was shown to be suitable for structural, quantitative, and qualitative assessment of complex transcriptomes and revealed new events mediated by ERBB2 overexpression, in addition to potential molecular targets for breast cancer that are driven by this oncogene.
- 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.
article 32 Citação(ões) na Scopus Transcriptional profile of fibroblasts obtained from the primary site, lymph node and bone marrow of breast cancer patients(2014) VALLE, Paulo Roberto Del; MILANI, Cintia; BRENTANI, Maria Mitzi; KATAYAMA, Maria Lucia Hirata; LYRA, Eduardo Carneiro de; CARRARO, Dirce Maria; BRENTANI, Helena; PUGA, Renato; LIMA, Leandro A.; ROZENCHAN, Patricia Bortman; NUNES, Barbara dos Santos; GOES, Joao Carlos Guedes Sampaio; FOLGUEIRA, Maria Aparecida Azevedo KoikeCancer-associated fibroblasts (CAF) influence tumor development at primary as well as in metastatic sites, but there have been no direct comparisons of the transcriptional profiles of stromal cells from different tumor sites. In this study, we used customized cDNA microarrays to compare the gene expression profile of stromal cells from primary tumor (CAF, n = 4), lymph node metastasis (N+, n = 3) and bone marrow (BM, n = 4) obtained from breast cancer patients. Biological validation was done in another 16 samples by RT-qPCR. Differences between CAF vs N+, CAF vs BM and N+ vs BM were represented by 20, 235 and 245 genes, respectively (SAM test, FDR < 0.01). Functional analysis revealed that genes related to development and morphogenesis were overrepresented. In a biological validation set, NOTCH2 was confirmed to be more expressed in N+ (vs CAF) and ADCY2, HECTD1, HNMT, LOX, MACF1, SLC1A3 and USP16 more expressed in BM (vs CAF). Only small differences were observed in the transcriptional profiles of fibroblasts from the primary tumor and lymph node of breast cancer patients, whereas greater differences were observed between bone marrow stromal cells and the other two sites. These differences may reflect the activities of distinct differentiation programs.- Influence of the interaction between nodal fibroblast and breast cancer cells on gene expression(2011) SANTOS, Rosangela Portilho Costa; BENVENUTI, Ticiana Thomazine; HONDA, Suzana Terumi; VALLE, Paulo Roberto Del; KATAYAMA, Maria Lucia Hirata; BRENTANI, Helena Paula; CARRARO, Dirce Maria; ROZENCHAN, Patricia Bortman; BRENTANI, Maria Mitzi; LYRA, Eduardo Carneiro de; TORRES, Cesar Henrique; SALZGEBER, Marcia Batista; KAIANO, Jane Haruko Lima; GOES, Joao Carlos Sampaio; FOLGUEIRA, Maria Aparecida Azevedo KoikeOur aim was to evaluate the interaction between breast cancer cells and nodal fibroblasts, by means of their gene expression profile. Fibroblast primary cultures were established from negative and positive lymph nodes from breast cancer patients and a similar gene expression pattern was identified, following cell culture. Fibroblasts and breast cancer cells (MDA-MB231, MDA-MB435, and MCF7) were cultured alone or co-cultured separated by a porous membrane (which allows passage of soluble factors) for comparison. Each breast cancer lineage exerted a particular effect on fibroblasts viability and transcriptional profile. However, fibroblasts from positive and negative nodes had a parallel transcriptional behavior when co-cultured with a specific breast cancer cell line. The effects of nodal fibroblasts on breast cancer cells were also investigated. MDA MB-231 cells viability and migration were enhanced by the presence of fibroblasts and accordingly, MDA-MB435 and MCF7 cells viability followed a similar pattern. MDA-MB231 gene expression profile, as evaluated by cDNA microarray, was influenced by the fibroblasts presence, and HNMT, COMT, FN3K, and SOD2 were confirmed downregulated in MDA-MB231 co-cultured cells with fibroblasts from both negative and positive nodes, in a new series of RT-PCR assays. In summary, transcriptional changes induced in breast cancer cells by fibroblasts from positive as well as negative nodes are very much alike in a specific lineage. However, fibroblasts effects are distinct in each one of the breast cancer lineages, suggesting that the inter-relationships between stromal and malignant cells are dependent on the intrinsic subtype of the tumor.
- RHOA, RAC1 and PAK1 evaluation in paired stromal fibroblasts of breast cancer primary and of lymph node metastasis: Importance of these biomarkers in lymph node invasion(2014) ROZENCHAN, Patricia Bortman; MUNDIM, Fiorita G.; ROELA, Rosimeire A.; KATAYAMA, Maria L.; PASINI, Fatima S.; BRENTANI, Helena; LYRA, Eduardo C.; FOLGUEIRA, Maria A. A. K.; BRENTANI, Maria M.