Angiotensin-(1 - 7) and Human Chorionic Gonadotropin (hCG) Modulate the Nuclear Transcription Factors or Nuclear Receptors Genes in the Tumorigenic Undifferentiated Breast Cancer Cell Line SKBR3

Abstract

Breast cancer is the most common cancer among women. Angiotensin-(1 - 7) [Ang-(1 - 7)] has been correlated with cancer antiproliferative and apoptotic effects, similar properties of the human Chorionic Gonadotrofin (hCG) . The aims of this work are to evaluate the role of Ang-(1 - 7) and of hCG in modulating the expression of Nuclear Receptors and Coregulators related genes in the tumorigenic breast cell line SK-BR3. Three experimental groups were created: control, hCG and hCG + Ang-(1 - 7). Cells were treated for 11 days and then had their RNA extracted. Samples were loaded into PCR Array plates containing 84 genes relate to Nuclear Receptors and Coregulators pathways. Gene expression data were used to construct canonical pathways (Metacore TM ). hCG and hCG + Ang-(1 - 7) treatments markedly modu late the expression of Nuclear Receptors and Coregulators related genes. hCG di f ferentially expressed 17% of the genes, being 29% upregulated and 71% downregulated. Meanwhile, hCG + Ang-(1 - 7) changed the expression of 30% of the genes on the plate, among these genes 56% were upregulated and 44% downregulated. Among these differentially ex pressed genes, we highlight Esr1, Nr2f2, and Nr2f1, Esr1, Hdac5, and Nr4A1 (>4 fold). Finally MetaCore analysis based on Gene Ontology (GO) generated six networks for hCG and ten networks for the combined treatment. All gen erated networks are related to regulation of apoptosis or to Programmed Cell Death processes. In summary, our results herein demonstrate that the modulation of sexual hormones and of other nuclear factor genes expression might underlie the tumorigenic protection effect and the induction of cell differentiation caused by the hormones hCG and Ang-(1 - 7), especially in Cancer Stem Cells.