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
3 resultados
Resultados de Busca
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- 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.
- 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.
- A Set of miRNAs, Their Gene and Protein Targets and Stromal Genes Distinguish Early from Late Onset ER Positive Breast Cancer(2016) BASTOS, E. P.; BRENTANI, H.; PEREIRA, C. A. B.; POLPO, A.; LIMA, L.; PUGA, R. D.; PASINI, F. S.; OSORIO, C. A. B. T.; ROELA, R. A.; ACHATZ, M. I.; TRAPE, A. P.; GONZALEZ-ANGULO, A. M.; BRENTANI, M. M.Breast cancer (BC) in young adult patients (YA) has a more aggressive biological behavior and is associated with a worse prognosis than BC arising in middle aged patients (MA). We proposed that differentially expressed miRNAs could regulate genes and proteins underlying aggressive phenotypes of breast tumors in YA patients when compared to those arising in MA patients. Objective: Using integrated expression analyses of miRs, their mRNA and protein targets and stromal gene expression, we aimed to identify differentially expressed profiles between tumors from YA-BC and MA-BC. Methodology and Results: Samples of ER+ invasive ductal breast carcinomas, divided into two groups: YA-BC (35 years or less) or MA-BC (50-65 years) were evaluated. Screening for BRCA1/2 status according to the BOADICEA program indicated low risk of patients being carriers of these mutations. Aggressive characteristics were more evident in YA-BC versus MA-BC. Performing qPCR, we identified eight miRs differentially expressed (miR-9, 18b, 33b, 106a, 106b, 210, 518a-3p and miR-372) between YA-BC and MA-BC tumors with high confidence statement, which were associated with aggressive clinicopathological characteristics. The expression profiles by microarray identified 602 predicted target genes associated to proliferation, cell cycle and development biological functions. Performing RPPA, 24 target proteins differed between both groups and 21 were interconnected within a network protein-protein interactions associated with proliferation, development and metabolism pathways over represented in YA-BC. Combination of eight mRNA targets or the combination of eight target proteins defined indicators able to classify individual samples into YA-BC or MA-BC groups. Fibroblast-enriched stroma expression profile analysis resulted in 308 stromal genes differentially expressed between YA-BC and MA-BC. Conclusion: We defined a set of differentially expressed miRNAs, their mRNAs and protein targets and stromal genes that distinguish early onset from late onset ER positive breast cancers which may be involved with tumor aggressiveness of YA-BC.