Aberrant DNA methylation of synaptophysin is involved in adrenal cortisol-producing adenoma

Drug addiction and treatment: An epigenetic perspective

Drug addiction is a complex disease affected by numerous genetic and environmental factors. Brain regions in reward pathway, neuronal adaptations, genetic and epigenetic interactions causing transcriptional enhancement or repression of multiple genes induce different addiction phenotypes for varying duration. Addictive drug use causes epigenetic alterations and similarly epigenetic changes induced by environment can promote addiction. Epigenetic mechanisms include DNA methylation and post-translational modifications like methylation, acetylation, phosphorylation, ubiquitylation, sumoylation, dopaminylation and crotonylation of histones, and ADP-ribosylation. Non-coding RNAs also induce epigenetic changes. This review discusses these above areas and stresses the need for exploring epidrugs as a treatment alternative and adjunct, considering the limited success of current addiction treatment strategies. Epigenome editing complexes have lately been effective in eukaryotic systems. Targeted DNA cleavage techniques such as CRISPR-Cas9 system, CRISPR-dCas9 complexes, transcription activator-like effector nucleases (TALENs) and zinc-finger nucleases (ZFNs) have been exploited as targeted DNA recognition or anchoring platforms, fused with epigenetic writer or eraser proteins and delivered by transfection or transduction methods. Efficacy of epidrugs is seen in various neuropsychiatric conditions and initial results in addiction treatment involving model organisms are remarkable. Epidrugs present a promising alternative treatment for addiction.

Deleted in lymphocytic leukemia 2 induces retinoic acid receptor beta promoter methylation and mitogen activated kinase-like protein activation to enhance viability and mobility of colorectal cancer cells

Abnormal expression of long non-coding RNAs (lncRNAs) is frequently linked to the pathogenesis of colorectal cancer (CRC). This work explored the function of lncRNA deleted in lymphocytic leukemia 2 (DLEU2) in CRC and the epigenetic mechanism. Candidate oncogenes in CRC were predicted using a GSE146587 dataset. DLEU2 was highly expressed in CRC according to the bioinformatic analysis and its high expression was detected in CRC cells compared to the normal colon epithelial cells (FHC). Downregulation of DLEU2 in CRC SW480 and HT29 cells suppressed viability, migration, invasiveness, and resistance to apoptosis of cells. The mRNA microarray analysis was performed to explore the key molecules mediated by DLEU2. Retinoic acid receptor beta (RARB) expression was elevated in cells after DLEU2 downregulation. The promoter methylation of RARB was enhanced in CRC cells compared to normal FHC cells. DLEU2 induced promoter methylation of RARB to downregulate its expression. Further silencing of RARB restored proliferation and invasiveness of cells blocked by sh-DLEU2. Upregulation of DLEU2 activated the mitogen activated kinase-like protein (MAPK) signaling pathway to trigger CRC progression. In conclusion, this study demonstrates that DLEU2 enhances viability and mobility of CRC cells by inducing RARB promoter methylation and activating the MAPK signaling pathway.

Interaction between DNMT3B and MYH11 via hypermethylation regulates gastric cancer progression

BACKGROUND

Gastric cancer (GC) has an unwelcoming prognosis when diagnosed at an advanced stage. The purpose of this study was to examine the expression of myosin heavy chain 11 (MYH11) in GC and mechanisms related.

METHODS

The MYH11 expression in GC was investigated via the SangerBox platform. MYH11 expression in GC tissues and cell lines was examined by immunohistochemistry, RT-qPCR, and western blot. The relationship between MYH11 expression and patients' prognosis was analyzed. The effects of MYH11 on the biological behaviors of GC cells were investigated by gain-of-function experiments. Bioinformatics analysis was used to find genes with relevance to MYH11 expression in GC. The relationship was verified by luciferase and ChIP-qPCR assays, followed by rescue assay validation. The causes of MYH11 downregulation in GC were verified by quantitative methylation-specific PCR. Finally, the effect of MYH11 on tumor growth was examined.

RESULTS

MYH11 was downregulated in GC and predicted poor prognoses. MYH11 reverted the malignant phenotype of GC cells. MYH11 repressed the TNFRSF14 expression by binding to the TNFRSF14 promoter. TNFRSF14 reversed the inhibitory effect of MYH11 on the malignant phenotype of GC cells. The methylation of the MYH11 promoter was elevated in GC, which was correlated with the elevated DNMT3B in GC. Overexpression of DNMT3B repressed transcription of MYH11 by promoting its methylation. Also, MYH11 upregulation inhibited tumor growth.

CONCLUSION

DNMT3B inhibits MYH11 expression by promoting its DNA methylation, thereby attenuating the repressive effect of MYH11 on the transcriptional of TNFRSF14 and promoting the progression of GC.

The role of TET proteins in stress-induced neuroepigenetic and behavioural adaptations

Over the past decade, critical, non-redundant roles of the ten-eleven translocation (TET) family of dioxygenase enzymes have been identified in the brain during developmental and postnatal stages. Specifically, TET-mediated active demethylation, involving the iterative oxidation of 5-methylcytosine to 5-hydroxymethylcytosine and subsequent oxidative derivatives, is dynamically regulated in response to environmental stimuli such as neuronal activity, learning and memory processes, and stressor exposure. Such changes may therefore perpetuate stable and dynamic transcriptional patterns within neuronal populations required for neuroplasticity and behavioural adaptation. In this review, we will highlight recent evidence supporting a role of TET protein function and active demethylation in stress-induced neuroepigenetic and behavioural adaptations. We further explore potential mechanisms by which TET proteins may mediate both the basal and pathological embedding of stressful life experiences within the brain of relevance to stress-related psychiatric disorders.

The Multi-Therapeutic Role of MSCs in Diabetic Nephropathy

Diabetic nephropathy (DN) is one of the most common diabetes mellitus (DM) microvascular complications, which always ends with end-stage renal disease (ESRD). Up to now, as the treatment of DN in clinic is still complicated, ESRD has become the main cause of death in diabetic patients. Mesenchymal stem cells (MSCs), with multi-differentiation potential and paracrine function, have attracted considerable attention in cell therapy recently. Increasing studies concerning the mechanisms and therapeutic effect of MSCs in DN emerged. This review summarizes several mechanisms of MSCs, especially MSCs derived exosomes in DN therapy, including hyperglycemia regulation, anti-inflammatory, anti-fibrosis, pro-angiogenesis, and renal function protection. We also emphasize the limitation of MSCs application in the clinic and the enhanced therapeutic role of pre-treated MSCs in the DN therapy. This review provides balanced and impartial views for MSC therapy as a promising strategy in diabetic kidney disease amelioration.