1. Integrated epigenetics of human breast cancer: synoptic investigation of targeted genes, microRNAs and proteins upon demethylation treatment.
- Author
-
Radpour R, Barekati Z, Kohler C, Schumacher MM, Grussenmeyer T, Jenoe P, Hartmann N, Moes S, Letzkus M, Bitzer J, Lefkovits I, Staedtler F, and Zhong XY
- Subjects
- Antimetabolites, Antineoplastic pharmacology, Apoptosis, Azacitidine analogs & derivatives, Azacitidine pharmacology, Blotting, Western, Breast Neoplasms drug therapy, Cell Line, Tumor, Cell Proliferation, Decitabine, Electrophoresis, Gel, Two-Dimensional, Female, Gene Expression Profiling, Gene Expression Regulation, Neoplastic, Gene Silencing, Humans, Oligonucleotide Array Sequence Analysis, Promoter Regions, Genetic genetics, RNA, Messenger genetics, Real-Time Polymerase Chain Reaction, Reverse Transcriptase Polymerase Chain Reaction, Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization, Biomarkers, Tumor genetics, Biomarkers, Tumor metabolism, Breast Neoplasms genetics, Breast Neoplasms metabolism, DNA Methylation, Epigenesis, Genetic, MicroRNAs physiology
- Abstract
Background: The contribution of aberrant DNA methylation in silencing of tumor suppressor genes (TSGs) and microRNAs has been investigated. Since these epigenetic alterations are reversible, it became of interest to determine the effects of the 5-aza-2'-deoxycytidine (DAC) demethylation therapy in breast cancer at different molecular levels., Methods and Findings: Here we investigate a synoptic model to predict complete DAC treatment effects at the level of genes, microRNAs and proteins for several human breast cancer lines. The present study assessed an effective treatment dosage based on the cell viability, cytotoxicity, apoptosis and methylation assays for the investigated cell lines. A highly aggressive and a non-aggressive cell line were investigated using omics approaches such as MALDI-TOF MS, mRNA- and microRNA expression arrays, 2-D gel electrophoresis and LC-MS-MS. Complete molecular profiles including the biological interaction and possible early and late systematic stable or transient effects of the methylation inhibition were determined. Beside the activation of several epigenetically suppressed TSGs, we also showed significant dysregulation of some important oncogenes, oncomiRs and oncosuppressors miRNAs as well as drug tolerance genes/miRNAs/proteins., Conclusions: In the present study, the results denote some new molecular DAC targets and pathways based on the chemical modification of DNA methylation in breast cancer. The outlined approach might prove to be useful as an epigenetic treatment model also for other human solid tumors in the management of cancer patients.
- Published
- 2011
- Full Text
- View/download PDF