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
9 resultados
Resultados de Busca
Agora exibindo 1 - 9 de 9
- MYC is expressed in the stromal and epithelial cells of primary breast carcinoma and paired nodal metastases(2015) MUNDIM, Fiorita Gonzales Lopes; PASINI, Fatima Solange; BRENTANI, Maria Mitzi; SOARES, Fernando Augusto; NONOGAKI, Suely; WAITZBERG, Angela Flayia LogulloThe MYC oncogene is directly involved in the proliferation, metabolism, progression and distant metastasis of breast cancer. Since metastatic spread to the lymph nodes is often the first indication of propensity for metastatic dissemination, the MYC status in nodal disease may represent a decision-making variable. However, the analysis of MYC expression in stromal cells, namely cancer-associated fibroblasts (CAFs), which are known to play a critical role in cancer progression, remains poorly reported. The aim of this study was to determine the expression of MYC and other markers, including estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2), p53, Ki67, epidermal growth factor receptor (EGFR), phosphorylated AKT (p-AKT) and phospho-mammalian target of rapamycin (p-mTOR) by immunohistochemistry in representative samples from 80 patients with ductal infiltrative breast cancer and 43 paired compromised axillary lymph nodes allocated in tissue microarrays (TMAs). The epithelial and stromal components of primary tumors and respective lymph node metastases were separately analyzed. MYC expression (cytoplasmic and nuclear) was a frequent event in the epithelial and stromal components of the primary tumors. The epithelial cells in the nodal metastases exhibited a trend for decreased MYC expression compared to that in the primary tumors (P=0.08) but retained the original status of the primary tumors for all other markers. The stromal cells were uniformly negative for ER, PR, HER2, p53, Ki67 and EGFR. Comparison of the stromas of primary tumors and respective lymph node metastases revealed a reduced frequency of nuclear MYC in 15% of the cases (P=0.003), whereas p-mTOR followed a similar trend (P=0.09). Analyses of the possible correlations among markers revealed that epithelial nuclear MYC was associated with p53 (P=0.048). This is an original study demonstrating a significant proportion of MYC expression (nuclear or cytoplasmic), as well p-mTOR and p-AKT expression, in the epithelial and stromal components of either the primary tumor or the nodal metastases. CAFs expressing MYC may establish an angiogenic microenvironment supporting cancer survival and facilitating colonization at the nodal metastatic site.
- Somatic mutations in breast and serous ovarian cancer young patients: a systematic review and meta-analysis(2015) ENCINAS, Giselly; MAISTRO, Simone; PASINI, Fatima Solange; KATAYAMA, Maria Lucia Hirata; BRENTANI, Maria Mitzi; BOCK, Geertruida Hendrika de; FOLGUEIRA, Maria Aparecida Azevedo KoikeObjective: our aim was to evaluate whether somatic mutations in five genes were associated with an early age at presentation of breast cancer (BC) or serous ovarian cancer (SOC). Methods: COSMIC database was searched for the five most frequent somatic mutations in BC and SOC. A systematic review of PubMed was performed. Young age for BC and SOC patients was set at <= 35 and <= 40 years, respectively. Age groups were also classified in <30years and every 10 years thereafter. Results: twenty six (1,980 patients, 111 younger) and 16 studies (598, 41 younger), were analyzed for BC and SOC, respectively. In BC, PIK3CA wild type tumor was associated with early onset, not confirmed in binary regression with estrogen receptor (ER) status. In HER2-negative tumors, there was increased frequency of PIK3CA somatic mutation in older age groups; in ER-positive tumors, there was a trend towards an increased frequency of PIK3CA somatic mutation in older age groups. TP53 somatic mutation was described in 20% of tumors from both younger and older patients; PTEN, CDH1 and GATA3 somatic mutation was investigated only in 16 patients and PTEN mutation was detected in one of them. In SOC, TP53 somatic mutation was rather common, detected in more than 50% of tumors, however, more frequently in older patients. Conclusion: frequency of somatic mutations in specific genes was not associated with early-onset breast cancer. Although very common in patients with serous ovarian cancer diagnosed at all ages, TP53 mutation was more frequently detected in older women.
conferenceObject Metastatic lymph node fibroblasts maintain similar profile of stromal biomarkers registered in primary breast carcinomas(2015) MUNDIM, Fiorita G. L.; PASINI, Fatima S.; NONOGAKI, Suely; SOARES, Fernando A.; BRENTANI, M. Mitzi; LOGULLO, Angela F.conferenceObject Ipsilateral breast cancer recurrence in conservative treatment for locally advanced breast cancer(2015) CARRARA, G. F. A.; NETO, C. S.; ABRAO-MACHADO, L. F.; NUNES, J. S.; FOLGUEIRA, M. A. A. K.; BRENTANI, M. M.; VIEIRA, R. A. C.conferenceObject Metastatic lymph node fibroblasts maintain similar profile of stromal biomarkers registered in primary breast carcinomas(2015) MUNDIM, Fiorita G. L.; PASINI, Fatima S.; NONOGAKI, Suely; SOARES, Fernando A.; BRENTANI, M. Mitzi; LOGULLO, Angela F.- 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.
conferenceObject Somatic mutations in Luminal HER2 negative tumors from young breast cancer patients.(2015) ENCINAS, Giselly; ESTEVEZ-DIZ, Maria Del Pilar; LYRA, Eduardo C.; KATAYAMA, Maria Lucia Hirata; PASINI, Fatima Solange; MAISTRO, Simone; SABELNYKOVA, Veronica; BOUTROS, Paul; BRENTANI, Maria Mitzi; BASSO, Ricardo; GOUVEA, Ana Carolina Ribeiro Chaves De; CHAMMAS, Roger; GOES, Joao Carlos Guedes Sampaio; FOLGUEIRA, Maria A. A. Koike- Reduction of HER2-associated lipogenic phenotype by docosahexaenoic acid (DHA) induces apoptosis in breast tumor cells harboring HER2 overexpression(2015) RAVACCI, Graziela R.; BRENTANI, Maria M.; FESTUCCIA, William; TORTELLI, Tharcisio; WAITZBERG, Angela F.; WAITZBERG, Dan L.
- Docosahexaenoic Acid Modulates a HER2-Associated Lipogenic Phenotype, Induces Apoptosis, and Increases Trastuzumab Action in HER2-Overexpressing Breast Carcinoma Cells(2015) RAVACCI, Graziela Rosa; BRENTANI, Maria Mitzi; TORTELLI, Tharcisio Citrangulo; TORRINHAS, Raquel Suzana M. M.; SANTOS, Jessica Reis; LOGULLO, Angela Flavia; WAITZBERG, Dan LinetzkyIn breast cancer, lipid metabolic alterations have been recognized as potential oncogenic stimuli that may promote malignancy. To investigate whether the oncogenic nature of lipogenesis closely depends on the overexpression of HER2 protooncogene, the normal breast cell line, HB4a, was transfected with HER2 cDNA to obtain HER2-overexpressing HB4aC5.2 cells. Both cell lines were treated with trastuzumab and docosahexaenoic acid. HER2 overexpression was accompanied by an increase in the expression of lipogenic genes involved in uptake (CD36), transport (FABP4), and storage (DGAT) of exogenous fatty acids (FA), as well as increased activation of ""de novo"" FA synthesis (FASN). We further investigate whether this lipogenesis reprogramming might be regulated by mTOR/PPAR gamma pathway. Inhibition of the mTORC1 pathway markers, p70S6 K1, SREBP1, and LIPIN1, as well as an increase in DEPTOR expression (the main inhibitor of the mTOR) was detected in HB4aC5.2. Based on these results, a PPAR gamma selective antagonist, GW9662, was used to treat both cells lines, and the lipogenic genes remained overexpressed in the HB4aC5.2 but not HB4a cells. DHA treatment inhibited all lipogenic genes (except for FABP4) in both cell lines yet only induced death in the HB4aC5.2 cells, mainly when associated with trastuzumab. Neither trastuzumab nor GW9662 alone was able to induce cell death. In conclusion, oncogenic transformation of breast cells by HER2 overexpression may require a reprogramming of lipogenic genetic that is independent of mTORC1 pathway and PPAR gamma activity. This reprogramming was inhibited by DHA.