Chromium ; toxicity ; DNA Methylation ; drug effects ; Epigenesis, Genetic ; Humans

Pulmonary arterial hypertension (PAH) is a rare but progressive and currently incurable disease, which is characterized by vascular remodeling in association with muscularization of the arterioles, medial thickening and plexiform lesion formation. Despite our advanced understanding of the pathogenesis of PAH and the recent therapeutic advances, PAH still remains a fatal disease. In addition, the susceptibility to PAH has not yet been adequately explained. Much evidence points to the involvement of epigenetic changes in the pathogenesis of a number of human diseases including cancer, peripheral hypertension and asthma. The knowledge gained from the epigenetic study of various human diseases can also be applied to PAH. Thus, the pursuit of novel therapeutic targets via understanding the epigenetic alterations involved in the pathogenesis of PAH, such as DNA methylation, histone modification and microRNA, might be an attractive therapeutic avenue for the development of a novel and more effective treatment. This review provides a general overview of the current advances in epigenetics associated with PAH, and discusses the potential for improved treatment through understanding the role of epigenetics in the development of PAH.
Animals ; DNA Methylation/drug effects ; Drug Discovery/methods ; *Epigenesis, Genetic/drug effects ; Genetic Therapy/methods ; Humans ; Hypertension, Pulmonary/*genetics/therapy ; MicroRNAs/*genetics

OBJECTIVEMethylation-specific epigenetic process and gene expression profiles of HeLa cells treated with ultra-high dilutions (HDs) of two plant extracts, Hydrastis canadensis (HC-30) and Marsdenia condurango (Condu-30), diluted 1060 times, were analyzed against placebo 30C (Pl-30) for alterations in gene profiles linked to epigenetic modifications.

METHODSSeparate groups of cells were subjected to treatment of Condu-30, HC-30, and Pl-30 prepared by serial dilutions and succussions. Global microarray data recorded on Affymetrix platform, using 25-mer probes were provided by iLifeDiscoveries, India. Slides were scanned with 3000 7G microarray scanner and raw data sets were extracted from Cel (raw intensity) files. Analyses of global microarray data profile, differential gene expression, fold change and clusters were made using GeneSpring GX12.5 software and standard normalization procedure. Before microarray study, concentration of RNA (ng/μL), RIN value and rRNA ratio for all the samples were analysed by Agilant Bioanalyzer 2100. Reverse transcriptase polymerase chain reaction (RT-PCR) and quantitative RT-PCR were done for analyzing SMAD-4 expression. Fluorescence-activated cell sorting study was further made to elucidate fate of cells at divisional stages. Methylation-specific restriction enzyme assay was conducted for ascertaining methylation status of DNA at specific sites.

RESULTSHDs of HC-30 and Condu-30 differentially altered methylation in specific regions of DNA and expression profiles of certain genes linked to carcinogenesis, as compared to Pl-30. Two separate cut sites were found in genomic DNA of untreated and placebo-treated HeLa cells when digested with McrBC, compared to a single cut observed in Condu-30-treated genomic DNA. SMAD-4 gene expression validated the expression pattern observed in microarray profile. Methylation-specific restriction enzyme assay elucidated differential epigenetic modifications in drug-treated and control cells.

CONCLUSIONHDs triggered epigenetic modifications and alterations in microarray gene expression profiles of many genes associated with carcinogenesis in HeLa cells in vitro.

Cell Cycle ; Cluster Analysis ; DNA Methylation ; Epigenesis, Genetic ; drug effects ; HeLa Cells ; Humans ; Hydrastis ; Marsdenia ; Plant Extracts ; pharmacology ; Transcriptome ; drug effects

In recent years, the incidences of male infertility and recurrent abortion are increasing. The causes of the conditions are varied and complex, but the affected stability of the genetic material in the sperm is an important etiological factor. Environmental pollutants may invade the body through respiration, diet and other channels, resulting in infertility and abortion or even affecting the reproductive system development of the offspring by changing the epigenetics of sperm DNA. In this paper, we propose the idea of using traditional Chinese medicine to prevent environmental pollutant-induced epigenetic changes of sperm DNA, hoping to provide a new insight into the protection against genetic material damage, male infertility, and recurrent abortion caused by environmental pollutants.
DNA Damage ; drug effects ; Drugs, Chinese Herbal ; pharmacology ; Environmental Pollutants ; toxicity ; Epigenesis, Genetic ; Humans ; Infertility, Male ; chemically induced ; prevention & control ; Male ; Medicine, Chinese Traditional ; Spermatozoa ; drug effects

OBJECTIVETo investigate the effect of phenyl-hexyl isothiocyanate (PHI) on acetylation and methylation of histone in acute lymphoblastic leukemia cell line Molt4.

METHODSThe inhibition of cell proliferation was observed by MTT method and clone suppression test. Apoptosis and cell cycle arrest were measured by flow cytometry. The alterations in histone acetyltransferase and acetylation and methylation of histones were detected by Western blot.

RESULTSPHI could up-regulate the expression of acetyltransferase (P300/CBP), markedly induced the accumulation of acetylated histone H3, H4 and methylated histone H3 lysine 4 (H3K4), and inhibited methylation on lysine 9 of H3 (H3K9). The epigenetic regulation resulted in cell cycle arrest at G0/G1 phase, and induction of apoptosis.

CONCLUSIONSPHI can modulate both histone methylation and acetylation. It may serve as a histone deacetylase inhibitor, and might be a potential novel anti-leukemia agent.

Acetylation ; drug effects ; Apoptosis ; drug effects ; Cell Cycle ; drug effects ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Epigenesis, Genetic ; Histone Deacetylases ; metabolism ; Histones ; metabolism ; Humans ; Isothiocyanates ; pharmacology ; Methylation ; drug effects

The occurrence and development of acute myeloid leukemia (AML) is not only related to gene mutations, but also influenced by abnormal epigenetic regulation, in which DNA methylation is one of the most important mechanisms. Abnormal DNA methylation may lead to the activation of oncogene and the inactivation of tumor suppressor gene, resulting in the occurrence of leukemia. The mutations of DNA methylation enzymes associated with AML may have certain characteristics. The AML with recurrent cytogenetic abnormalities is also related to abnormal methylation. Some fusion genes can alter DNA methylation status to participate in the pathogenesis of leukemia. In addition, chemotherapy drug resistance in patients with AML is associated with the change of gene methylation status. Considering the reversibility of the epigenetic modification, targeted methylation therapy has become a hotspot of AML research.
DNA Methylation ; drug effects ; genetics ; physiology ; DNA Modification Methylases ; genetics ; physiology ; Drug Resistance, Neoplasm ; genetics ; Epigenesis, Genetic ; genetics ; physiology ; Humans ; Leukemia, Myeloid, Acute ; etiology ; genetics ; pathology ; Mutation ; genetics

BACKGROUNDBoth in vitro and in vivo data have demonstrated the TGFBI gene functions as a putative tumor suppressor and is frequently downregulated in human tumors of different histological types. The hypermethylation of the TGFBI promoter, as one of the main regulatory mechanisms, is associated with TGFBI silencing. In this study, we used a methylation-specific PCR (MSP) method to evaluate the methylation status of the TGFBI promoter in human leukemias.

METHODSReal-time RT-PCR and methylation-specific PCR approaches were performed to define the TGFBI expression and promoter methylation in human leukemia cell lines and clinical samples. Genomic DNA was isolated from peripheral blood mononuclear cells from leukemia patients, bisulfite-converted, and analyzed by the MSP method.

RESULTSHypermethylation of the TGFBI promoter occurred in leukemia cell lines and demethylation treatment reexpressed TGFBI at a substantially increased level in most of leukemia cell lines tested. Furthermore, a much higher level of CpG island methylation and a significantly lower TGFBI expression were also identified in clinical leukemia samples.

CONCLUSIONThe results suggest an important role of promoter methylation in regulating TGFBI expression in leukemia, which provides a useful diagnostic marker for clinical management of human leukemias.

Cell Line, Tumor ; CpG Islands ; genetics ; DNA Methylation ; drug effects ; genetics ; Epigenesis, Genetic ; drug effects ; genetics ; Extracellular Matrix Proteins ; genetics ; Humans ; Leukemia ; epidemiology ; Promoter Regions, Genetic ; genetics ; Reverse Transcriptase Polymerase Chain Reaction ; Sulfites ; pharmacology ; Transforming Growth Factor beta ; genetics

The aim of this study was to illustrate the mechanism of inhibiting the cell growth in diffuse large B-cell lymphoma by histone deacetylase inhibitor valproic acid (VPA) combined with mTOR inhibitor temsirolimus (TEM). MTT assay and Wright's stain were used to assess cell growth inhibition and to detect the cell morphological changes respectively. The cell apoptosis, cell cycle and cell autophagy were determined by flow cytometry. Ultrastructure changes were confirmed by electron microscopy. Protein changes were detected by Western blot. The results showed that both VPA and TEM alone inhibited cell proliferation and the effect was more obvious in the combination group. VPA combined with TEM induced cell arrest in G0/G1 phase and upregulated the expression of autophagy-related protein LC3, without cell apoptosis. Moreover, typical autophagosomes were observed, further confirming the presence of autophagy. Western blot showed the changes of proteins involved in autophagy signaling pathway. VPA decreased HDAC1 and HDAC3 expression and increased histone acetylation, suggesting that VPA also affected lymphoma cell proliferation through epigenetic modification. It is concluded that the combined treatment of VPA and TEM induces cell cycle arrest and cell autophagy, which provides a new clue for their clinical application in diffuse large B-cell lymphoma.
Autophagy ; drug effects ; Cell Cycle Checkpoints ; drug effects ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Epigenesis, Genetic ; Histone Deacetylase 1 ; metabolism ; Histone Deacetylases ; metabolism ; Humans ; Lymphoma, Large B-Cell, Diffuse ; pathology ; Microtubule-Associated Proteins ; metabolism ; Sirolimus ; administration & dosage ; analogs & derivatives ; pharmacology ; Valproic Acid ; administration & dosage ; pharmacology

Insufficient epigenetic reprogramming of donor nuclei is believed to be one of the most important causes of low development efficiency of mammalian somatic cell nuclear transfer (SCNT). Previous studies have shown that both the in vitro and in vivo development of mouse SCNT embryos could be increased significantly by treatment with various histone deacetylase inhibitors (HDACi), including Trichostatin A, Scriptaid, and m-carboxycinnamic acid bishydroxamide (CBHA), in which only the effect of CBHA has not yet been tested in other species. In this paper we examine the effect of CBHA treatment on the development of porcine SCNT embryos. We have discovered the optimum dosage and time for CBHA treatment: incubating SCNT embryos with 2 μmol/L CBHA for 24 h after activation could increase the blastocyst rate from 12.7% to 26.5%. Immunofluorescence results showed that the level of acetylation at histone 3 lysine 9 (AcH3K9), acetylation at histone 3 lysine 18 (AcH3K18), and acetylation at histone 4 lysine 16 (AcH4K16) was raised after CBHA treatment. Meanwhile, CBHA treatment improved the expression of development relating genes such as pou5f1, cdx2, and the imprinted genes like igf2. Despite these promising in vitro results and histone reprogramming, the full term development was not significantly increased after treatment. In conclusion, CBHA improves the in vitro development of pig SCNT embryos, increases the global histone acetylation and corrects the expression of some developmentally important genes at early stages. As in mouse SCNT, we have shown that nuclear epigenetic reprogramming in pig early SCNT embryos can be modified by CBHA treatment.
Acetylation ; Animals ; Blastocyst ; cytology ; Cell Nucleus ; metabolism ; Cinnamates ; pharmacology ; Embryo, Mammalian ; drug effects ; metabolism ; Embryonic Development ; drug effects ; Epigenesis, Genetic ; Female ; Gene Expression ; Histone Deacetylase Inhibitors ; pharmacology ; Histones ; metabolism ; Homeodomain Proteins ; genetics ; metabolism ; In Vitro Techniques ; Insulin-Like Growth Factor II ; genetics ; metabolism ; Nuclear Transfer Techniques ; Octamer Transcription Factor-3 ; genetics ; metabolism ; Swine

OBJECTIVETo investigate the mechanism of loss of human esophageal cancer-related gene 4 (ECRG4) expression in esophageal squamous cell carcinoma (ESCC.)

METHODSPCR-SSCP and DNA sequencing analysis were used to detect the mutation of ECRG4 exons in esophageal cancer and matched adjacent normal tissues of 80 patients. DNA bisulfite-modifying ssPCR sequencing assay was used to examine the methylation status of ECRG4 promoter in human esophageal squamous cell carcinoma EC9706 cells. The re-expression of ECRG4 mRNA was examined by RT-PCR in EC9706 cells, after treatment with either demethylation drug 5-aza-2'-deoxycytidine or arsenic trioxide.

RESULTSNo mutation in the four ECRG4 exons was found in all the ESCC and matched normal adjacent tissues. RT-PCR showed that 11 of 16 CpG islands of ECRG4 promoter were hypermethylated, while ECRG4 mRNA expression level was undetectable in the EC9706 cells. The ECRG4 mRNA was re-expressed after treatment with either demethylation drug 5-aza-2'-deoxycytidine or arsenic trioxide.

CONCLUSIONThe epigenetic mechanism of methylation is a reason of loss of ECRG4 gene expression in the ESCC cell line EC9706.

Antimetabolites, Antineoplastic ; pharmacology ; Antineoplastic Agents ; pharmacology ; Arsenicals ; pharmacology ; Azacitidine ; analogs & derivatives ; pharmacology ; Carcinoma, Squamous Cell ; genetics ; metabolism ; pathology ; Cell Line, Tumor ; CpG Islands ; genetics ; DNA Methylation ; Epigenesis, Genetic ; Esophageal Neoplasms ; genetics ; metabolism ; pathology ; Exons ; Gene Expression Regulation, Neoplastic ; drug effects ; Humans ; Mutation ; Neoplasm Proteins ; genetics ; metabolism ; Oxides ; pharmacology ; Promoter Regions, Genetic ; RNA, Messenger ; metabolism