ABSTRACT
BACKGROUND: Breast cancer is the second most common cancer worldwide. N, N, N', N'-Tetrakis (2-pyridylmethyl)-ethylenediamine (TPEN) is a lipid-soluble zinc metal chelator that induces apoptosis in cancer cells through oxidative stress (OS). However, the effectiveness and the mechanisms involved in TPENinduced cell death in mammary adenocarcinoma cells in vitro and in vivo are still unclear. OBJECTIVE: This study aimed to evaluate the cytotoxic effect of TPEN in mouse embryonic fibroblasts (MEFs, as normal control cells) and mammary adenocarcinoma cancer cells (TS/A cells) in vitro and in a mammary tumor model in vivo. METHODS: Cells were treated with TPEN (0-3 µM), and changes in nuclear chromatin and DNA, mitochondrial membrane potential (ΔΨm), and intracellular reactive oxygen species (ROS) levels were determined by both fluorescence microscopy and flow cytometry. Cell proliferation and the cell cycle were also analyzed. Cellular markers of apoptosis were evaluated by Western blot. Finally, the effect of TPEN in a mammary adenocarcinoma tumor model in vivo was determined by immunohistological analyses. RESULTS: TPEN induced apoptosis in TS/A cells in a dose-dependent manner, increasing nuclear chromatin condensation, DNA fragmentation, cell cycle arrest and ΔΨm loss. Additionally, TPEN increased dichlorofluorescein fluorescence (DCF+) intensity, indicative of ROS production; increased DJ-1-Cys106-sulfonate expression, a marker of intracellular H2O2 stress; induced p53 and PUMA upregulation; and activated caspase-3. Moreover, TPEN induced mammary cancer cell elimination and tumor size reduction in vivo 48 h after treatment through an OS-induced apoptotic mechanism. CONCLUSION: TPEN selectively induces apoptosis in TS/A cells through an H2O2-mediated signaling pathway. Our findings support the use of TPEN as a potential treatment for breast cancer.
Subject(s)
Adenocarcinoma/drug therapy , Antineoplastic Agents/pharmacology , Caspase 3/metabolism , Ethylenediamines/pharmacology , Hydrogen Peroxide/metabolism , Adenocarcinoma/metabolism , Adenocarcinoma/pathology , Animals , Antineoplastic Agents/chemistry , Cell Death/drug effects , Cell Line , Cell Proliferation/drug effects , Drug Screening Assays, Antitumor , Ethylenediamines/chemistry , Mice , Mice, Inbred BALB C , Signal Transduction/drug effectsABSTRACT
El estudio del perfil de expresión génica en las células eucariotas se constituye como una herramienta importante en el entendimiento de las huellas moleculares generadas en respuesta a un estímulo farmacológico. A partir de Petiveria alliacea, una de las plantas colombianas con actividad antitumoral, se ha obtenido la fracción FAST 8 7:3, en la cual se han encontrado diferentes compuestos, como el trisulfuro de dibencilo, uno de los componentes antitumorales más potentes reportados para la planta. Esta fracción también posee actividad citotóxica sobre la línea de células tumorales K562 e induce cambios en el perfil de expresión de genes, que podrían estar relacionados de alguna forma con la actividad antitumoral tradicional reportada para esta planta. Esta actividad puede ser ejercida, en parte, por la presencia del trisulfuro de dibencilo y por la actividad de los otros componentes de la fracción. En este contexto, proponemos el uso del ADNc-AFLP como herramienta útil en la tamización del perfil de genes transcritos en las células tumorales y, también, como herramienta útil para el descubrimiento de nuevos fármacos antitumorales...
Abstract Gene expression profile in eukaryotic cells is a very useful tool to understand the molecular footprint responsible for the pharmacological response to a stimulus. In the present study a fraction named FAST 8 (7:3), obtained from Petiveria alliacea, was used as stimulus to track out the gene expression profile on K562 cell line. P. alliacea is a plant that grows in Colombia, and in traditional medicine is used for its anti-tumoral activity. Of the different compounds present in the fraction, dibenzyl trisulfide (DTS), is a compound described by previous reports to have anti-tumoral properties. The fraction exhibits cytotoxic activity over tumor cell line K562 inducing changes in gene expression profile. DTS might be in part responsible for the fraction activity, but the other compounds may also contribute to the biological response. Herein, we propose the use of cDNAAFLP as a useful tool for gene expression profile screening of tumoral cells and in the discovery of new anti-tumoral drugs...