TIP60: an actor in acetylation of H3K4 and tumor development in breast cancer.

Aim: The acetyltransferase TIP60 is reported to be downregulated in several cancers, in particular breast cancer, but the molecular mechanisms resulting from its alteration are still unclear.

Materials & Methods: In breast tumors, H3K4ac enrichment and its link with TIP60 were evaluated by chromatin immunoprecipitation-qPCR and re-chromatin immunoprecipitation techniques. To assess the biological roles of TIP60 in breast cancer, two cell lines of breast cancer, MDA-MB-231 (ER-) and MCF-7 (ER+) were transfected with shRNA specifically targeting TIP60 and injected to athymic Balb-c mice.

SIRT1-dependent epigenetic regulation of H3 and H4 histone acetylation in human breast cancer.

Breast cancer is the most frequently diagnosed malignancy in women worldwide. It is well established that the complexity of carcinogenesis involves profound epigenetic deregulations that contribute to the tumorigenesis process. Deregulated H3 and H4 acetylated histone marks are amongst those alterations.

A new metabolic gene signature in prostate cancer regulated by JMJD3 and EZH2.

Histone methylation is essential for gene expression control. Trimethylated lysine 27 of histone 3 (H3K27me3) is controlled by the balance between the activities of JMJD3 demethylase and EZH2 methyltransferase. This epigenetic mark has been shown to be deregulated in prostate cancer, and evidence shows H3K27me3 enrichment on gene promoters in prostate cancer.

Dual SIRT1 expression patterns strongly suggests its bivalent role in human breast cancer.

Breast cancer is the most common cancer in women, and the leading cause of cancer death in women worldwide. SIRT1 (silent mating type information regulation 2 homolog) 1 is a class-III histone deacetylase involved in apoptosis regulation, DNA repair and tumorigenesis. However, its role in breast carcinoma remains controversial, as both tumor-suppressive and tumor-promoting functions have been reported.

The Epigenetic Landscape of Promoter Genome-wide Analysis in Breast Cancer.

Breast cancer is a heterogeneous disease due to its clinico-pathological features and response to therapy. The classification of breast tumors based on their hormone receptor status and pathologic features. Post-translational histone modifications come into prominence for regulation of gene expression in cancer pathogenesis.

Global analysis of H3K27me3 as an epigenetic marker in prostate cancer progression.

Background: H3K27me3 histone marks shape the inhibition of gene transcription. In prostate cancer, the deregulation of H3K27me3 marks might play a role in prostate tumor progression.

Methods: We investigated genome-wide H3K27me3 histone methylation profile using chromatin immunoprecipitation (ChIP) and 2X400K promoter microarrays to identify differentially-enriched regions in biopsy samples from prostate cancer patients.

High-throughput «Omics» technologies: New tools for the study of triple-negative breast cancer.

Triple negative breast cancer (TNBC) represents about 15% to 20% of all breast cancers and is typically associated with poorer outcome than other breast cancer subtypes. The heterogeneity of this breast cancer subtype and present lack of clinically established targeted therapies further complicates treatment of patients. The treatment of TNBC emphasizes enhancing health care and developing personalized medicine.

H3K4 acetylation, H3K9 acetylation and H3K27 methylation in breast tumor molecular subtypes.

Aim: Here, we investigated how the St Gallen breast molecular subtypes displayed distinct histone H3 profiles.

Patients & Methods: 192 breast tumors divided into five St Gallen molecular subtypes (luminal A, luminal B HER2-, luminal B HER2+, HER2+ and basal-like) were evaluated for their histone H3 modifications on gene promoters.

Results: ANOVA analysis allowed to identify specific H3 signatures according to three groups of genes: hormonal receptor genes (ERS1, ERS2, PGR), genes modifying histones (EZH2, P300, SRC3) and tumor suppressor gene (BRCA1).

Epigenetic Modifications with DZNep, NaBu and SAHA in Luminal and Mesenchymal-like Breast Cancer Subtype Cells.

Background/aim: Numerous studies have shown that breast cancer and epigenetic mechanisms have a very powerful interactive relation. The MCF7 cell line, representative of luminal subtype and the MDA-MB 231 cell line representative of mesenchymal-like subtype were treated respectively with a Histone Methyl Transferase Inhibitors (HMTi), 3-Deazaneplanocin hydrochloride (DZNep), two histone deacetylase inhibitors (HDACi), sodium butyrate (NaBu), and suberoylanilide hydroxamic acid (SAHA) for 48 h.

Materials And Methods: Chromatin immunoprecipitation (ChIP) was used to observe HDACis (SAHA and NaBu) and HMTi (DZNep) impact on histones and more specifically on H3K27me3, H3K9ac and H3K4ac marks with Q-PCR analysis of BRCA1, SRC3 and P300 genes.

A bivalent role of TIP60 histone acetyl transferase in human cancer.

Acetylation is a major modification that is required for gene regulation, genome maintenance and metabolism. A dysfunctional acetylation plays an important role in several diseases, including cancer. A group of enzymes-lysine acetyltransferases are responsible for this modification and act in regulation of transcription as cofactors and by acetylation of histones and other proteins.

The Role of Soy Phytoestrogens on Genetic and Epigenetic Mechanisms of Prostate Cancer.

Soy phytoestrogens are dietary components with considerable effects on reducing the incidence of prostate cancer. Epidemiological studies demonstrated that occurrence of prostate cancer is relatively low in Asia and Southern Europe, a status associated with consuming of soy isoflavones, such as genistein, daidzein, and glycitein. Soy phytoestrogens exert their activity on molecular mechanisms, including cell-cycle control, induction of apoptosis, inhibition of angiogenesis, and metastasis.

Genome-wide DNA methylation modified by soy phytoestrogens: role for epigenetic therapeutics in prostate cancer?

In prostate cancer, DNA methylation is significantly associated with tumor initiation, progression, and metastasis. Previous studies have suggested that soy phytoestrogens might regulate DNA methylation at individual candidate gene loci and that they play a crucial role as potential therapeutic agents for prostate cancer. The purpose of our study was to examine the modulation effects of phytoestrogens on a genome-wide scale in regards to DNA methylation in prostate cancer.

Prostate cancer: The main risk and protective factors-Epigenetic modifications.

With 13 million new cases worldwide every year, prostate cancer is as a very real public health concern. Prostate cancer is common in over-50s men and the sixth-leading cause of cancer-related death in men worldwide. Like all cancers, prostate cancer is multifactorial - there are non-modifiable risk factors like heredity, ethnicity and geographic location, but also modifiable risk factors such as diet.

The association between histone 3 lysine 27 trimethylation (H3K27me3) and prostate cancer: relationship with clinicopathological parameters.

Background: It is well established that genetic and epigenetic alterations are common events in prostate cancer, which may lead to aberrant expression of critical genes. The importance of epigenetic mechanisms in prostate cancer carcinogenesis is increasingly evident. In this study, the focus will be on histone modifications and the primary objectives are to map H3K27me3 marks and quantify RAR beta 2, ER alpha, SRC3, RGMA, PGR, and EZH2 gene expressions in prostate cancer tissues compared to normal tissues.

Epigenetic mechanisms of breast cancer: an update of the current knowledge.

Epigenetic alterations are heritable changes in gene expression that occur without causing any change in DNA sequence. They are important key factors for cancer development and prognosis. Breast cancer is induced by the accumulation of altered gene regulation.

Epigenetic modifications in prostate cancer.

Prostate cancer is the most common cancer in men and the second leading cause of cancer deaths in men in France. Apart from the genetic alterations in prostate cancer, epigenetics modifications are involved in the development and progression of this disease. Epigenetic events are the main cause in gene regulation and the three most epigenetic mechanisms studied include DNA methylation, histone modifications and microRNA expression.