Possible pharmacological and biochemical modulation of mammary stem cells by renin angiotensin system components

• Grant number: 11/10516-9
• Support Opportunities: Regular Research Grants
• Start date: September 01, 2011
• End date: August 31, 2013
• Field of knowledge: Health Sciences - Medicine - Maternal and Child Health
• Principal Investigator: Ismael Dale Cotrim Guerreiro da Silva
• Grantee: Ismael Dale Cotrim Guerreiro da Silva
• Host Institution: Escola Paulista de Medicina (EPM). Universidade Federal de São Paulo (UNIFESP). Campus São Paulo. São Paulo , SP, Brazil
• Associated researchers: Silvana Aparecida Alves Corrêa

Abstract

Breast cancer is the most common malignancy among women, accounting for thousandsof deaths annually. Among the various mediators that act in the carcinogenic process,the components of Renin Angiotensin System (RAS) have assumed an important role.Angiotensin II (Ang II), better known peptide obtained from the cascade of events ofthe RAS, has vasoconstrictive, angiogenic, hyperplastic, proliferative andmetastatic. On the other hand, angiotensin-(1-7) [Ang-(1-7)], another peptide belongingto the RAS and which has been extensively studied lately, triggers vasodilator actions,antiproliferative and apoptotic effects, contrary to the ones generated by Ang II. It isknown that solid tumors have a heterogeneous cellular composition and only a smallportion of its cells has the capacity to proliferate and generate new tumors. Recently ithas been proposed that this differential proliferation skills among cells from the sametumoric mass, could be explained by the fact that only a certain cell subgroup with theprimordial characteristics (cancer stem cells CSCs) could give rise to new tumors. Thisbeing the case, the aim of this study is to evaluate the role of Ang II and Ang-(1-7) inthe proliferation and progression of breast tumor stem cells (MDA MB231 and SKBR3)and of normal breast epithelial cells too (MCF-10 A and MCF10F) throughbiochemical, phenotypic and molecular methods. All cell lines in the study will besubmitted to the ALDEFLUOR assay in order to obtain a differential staining of stemcells from their progenies (Genestier et al ., 2010) and, after that, they will be separatedby FACS. The following techniques will be performed with these cells after theirseparation: cell proliferation analysis ( MTT), apoptosis, and viability (GUAVAcytometry), senescence, markers CD44 + and CD24- expression assessing, metastasis inthe NUDE mouse, ductulogênesis, invasion / migration, and eventually differentialexpression analysis of genes in PCR array assays (SA Bioscience) and Real Time PCR. (AU)