DNMT3B Expression Research Articles

EZH2 promotes angiogenesis in peritoneal dialysis by epigenetically activating SP4 expression in the IL-6/sIL-6R signalling pathway

Background: Interleukin-6 (IL-6)/soluble IL-6 receptor (sIL-6R) promotes peritoneal angiogenesis by stimulating SP4-mediated vascular endothelial growth factor (VEGF) production in peritoneal dialysis (PD). Moreover, histone methyltransferase enhancer of zeste homologue 2 (EZH2) is involved in IL-6/sIL-6R signalling via the acceleration of vascular endothelial growth factor (VEGF)-induced angiogenesis. However, the molecular mechanism underlying how EZH2 epigenetically activates VFGF expression in IL-6/sIL-6R signalling during PD is still unclear. Methods and Results: In this study, we measured the expression of EZH2, DNMT3B and SP4 in human peritoneal mesothelial cells (HPMCs) treated with IL-6/sIL-6R stimulation and/or EZH2 overexpression, silencing or inhibition. Methylation of the CpG site in the SP4 promoter region and VEGF production were measured under these treatments in HPMCs. Moreover, tube formation in human umbilical vein endothelial cells (HUVECs) was detected following treatment with conditioned media from these stimulated HPMCs. The 5/6 nephrectomy (5/6Nx) rat model was established, and the rats were injected with peritoneal dialysate. EZH2, DNMT3B and SP4 expression and microvessels were analysed in 5/6Nx + PD rats treated with IL-6/sIL-6R and EZH2 overexpression. The results showed that IL-6/sIL-6R and EZH2 overexpression enhanced the expression of EZH2, DNMT3B and SP4, but EZH2 silencing/inhibition reduced these expression levels. The results for VEGF production and tube formation in vitro followed the same trend. IL-6/sIL-6R and EZH2 overexpression increased the methylation percentage of the -170 bp CpG site in the SP4 promoter region in HPMCs. Moreover, IL-6/sIL-6R and EZH2 overexpression stimulated EZH2, DNMT3B and SP4 expression and promoted angiogenesis in 5/6Nx + PD rats. Conclusions: Thus, this study indicated that EZH2 is involved in IL-6/sIL-6R signalling and epigenetically regulates SP4 expression, thereby stimulating VEGF production and angiogenesis in PD. Targeting EZH2 is expected to be a novel therapeutic approach for end-stage renal disease (ESRD) patients with PD treatment.

Overexpression of lncRNA-MEG3 inhibits endometrial cell proliferation and invasion via miR-21–5p/DNMT3B/Twist

Recent studies have found that lncRNA-MEG3(MEG3) plays an important role in the development of EMs (Endometriosis), but the specific mechanism needs to be further explored. This study aimed to investigate the effect of MEG3 on the proliferation, invasion of EMs cells. The authors used RT-qPCR to detect the expression of MEG3 and miR-21–5p in EMs tissues and hESCs cells, MTT and Transwell to detect cell proliferation and invasion, western blotting assay to detect the expression of DNMT3B and Twist, MSP to detect the methylation of Twist. The present study's detection results showed that MEG3 was lowly expressed in EMs tissues and hESCs cells, and overexpression of MEG3 could down-regulate miR-21–5p and inhibit endometrial cell proliferation and invasion. In addition, overexpression of MEG3 upregulated the expression of DNMT3B and promoted the methylation of TWIST. In conclusion, the present findings suggest that MEG3 is downregulated in EMs tissues, and overexpression of MEG3 can promote the activity of DNA methyltransferase DNMT3B by downregulating miR-21–5p, thereby promoting the methylation of Twist, downregulating Twist level to inhibits hESCs cells proliferation and invasion.

Ovaryum kriyoprezervasyonu ve yeniden transplantasyondan sonra Dnmt3a ve Dnmt3b protein ifadelerinin düşmesi bu süreçte DNA metilasyonunun bozulduğunu gösterir

Objective DNA methylation includes maintenance and de novo methylation process that are catalyzed by DNA methyltransferase (Dnmt) enzymes and these enzymes possess crucial roles in methylation of genes associated with the development of ovarian follicles. The aim of this study is to evaluate whether expression of Dnmt3a and Dnmt3b protein levels change after cryopreservation and re-transplantation of ovarian tissue in rats. Methods Four groups were designed as; fresh control (FC), frozen/thawed (FT), fresh re-transplanted (T), and frozen/thawed and re-transplanted (FTT). Slow freezing was used to cryopreserve the ovarian tissue pieces and expression of Dnmt3a and Dnmt3b proteins was assessed by immunohistochemistry. Result Expression of Dnmt3a and Dnmt3b significantly decreased in ovarian follicles in FT, T and FTT groups when compared FC. Conclusion Expression of Dnmt enzymes has been altered both after cryopreservation alone and following re-transplantation cycles which may lead to disturbed DNA methylation processes during rat folliculogenesis

Retracted: HDAC2 Induces DNA Methyltransferase DNMT3B Expression to Regulate the Wnt Signaling Pathway and Thus Promotes Glioma Development and Progression.

[This retracts the article DOI: 10.1155/2022/1948766.].

Maternal exercise upregulates the DNA methylation of Agtr1a to enhance vascular function in offspring of hypertensive rats.

The angiotensin II signaling system regulates vascular dysfunction and is involved in the programming of hypertension. Maternal exercise has been linked to both short-term and long-term benefits for the mother and fetus. However, the impacts of maternal exercise on the intravascular renin-angiotensin system (RAS) in hypertensive offspring remain unexamined. This study examined whether maternal exercise has an epigenetic effect in repressing angiotensin II type 1 receptor (AT1R) expression, which leads to favorable alterations in the mesenteric artery (MA) function of spontaneously hypertensive offspring. Spontaneously hypertensive rats (SHRs) and Wistar-Kyoto (WKY) pregnant rats were randomly divided into an exercise group and a control group. Blood pressure, vascular tone, AT1R protein and mRNA expression, and AT1R gene (Agtr1a) promoter methylation status were examined in the MAs of 3-month-old male offspring. Maternal exercise significantly reduced the resting blood pressure and cardiovascular reactivity of offspring from SHRs. Furthermore, Ang II-AT1R activity in regulating vascular tone and AT1R expression was decreased in the MAs of the SHR offspring from the exercise groups. Importantly, exercise during gestation suppressed AT1R expression via hypermethylation of the Agtr1a promoter region and upregulated DNA methyltransferase (DNMT) expression in MAs of SHR offspring. These results suggest that maternal exercise upregulates DNMT expression, resulting in hypermethylation and repression of the Agtr1a gene, which may prevent MA dysfunction in the offspring of SHRs. A mechanistic model on the epigenetics of exercise during pregnancy. Maternal exercise during pregnancy triggers hypermethylation and transcriptional suppression of the Agtr1a gene via increased DNMT1 and DNMT3B expression in MAs of SHR offspring. Downregulation of AT1R expression reduces the contribution of Ang II to vascular tone, ultimately improving vascular structure and function. VSMC vascular smooth muscle cell; Ang II angiotensin II; AT1aR angiotensin type 1 receptor (AT1R) alpha subtypes; Agtr1a AT1R alpha isoform gene; MAs mesenteric arteries; BP blood pressure.

LncRNA FPASL suppresses fibroblast proliferation through its DNA methylation via DNMT3b in hypertrophic scar.

Long noncoding RNAs (lncRNAs) are increasingly being implicated as key regulators of cell proliferation, apoptosis, and differentiation. However, the molecular mechanisms of specific lncRNAs in the context of hypertrophic scar remain largely unclear. Here, we find that the lncRNA FPASL (fibroblast proliferation-associated LncRNA) is downregulated in HS, and FPASL reduces fibroblast proliferation and colony formation and blocks cell cycle progression. Using GO annotation enrichment analysis along with AZC (a specific inhibitor of DNA methylation), we identify that DNA methylation is responsible for downregulating FPASL in hypertrophic scar. Subsequent studies demonstrate that high expression of DNMT3b inhibits FPASL expression in HS. Mechanistic study reveals a significant increase in fibroblast proliferation after transfection with LNA-FPASL, which is further inhibited by knockdown of DNMT3b. Thus, our study reveals that DNMT3b mediates hypermethylation of the lncRNA FPASL promoter and the downregulation of lncRNA FPASL promotes fibroblast proliferation in hypertrophic scar.

Inhibition of DNMT3B and PI3K/AKT/mTOR and ERK Pathways as a Novel Mechanism of Volasertib on Hypomethylating Agent-Resistant Cells.

Resistance to hypomethylating agents (HMAs) in myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML) is a concerning problem. Polo-like kinase 1 (PLK1) is a key cell cycle modulator and is known to be associated with an activation of the PI3K pathway, which is related to the stabilization of DNA methyltransferase 1 (DNMT1), a target of HMAs. We investigated the effects of volasertib on HMA-resistant cell lines (MOLM/AZA-1 and MOLM/DEC-5) derived from MOLM-13, and bone marrow (BM) samples obtained from patients with MDS (BM blasts >5%) or AML evolved from MDS (MDS/AML). Volasertib effectively inhibited the proliferation of HMA-resistant cells with suppression of DNMTs and PI3K/AKT/mTOR and ERK pathways. Volasertib also showed significant inhibitory effects against primary BM cells from patients with MDS or MDS/AML, and the effects of volasertib inversely correlated with DNMT3B expression. The DNMT3B-overexpressed AML cells showed primary resistance to volasertib treatment. Our data suggest that volasertib has a potential role in overcoming HMA resistance in patients with MDS and MDS/AML by suppressing the expression of DNMT3 enzymes and PI3K/AKT/mTOR and ERK pathways. We also found that DNMT3B overexpression might be associated with resistance to volasertib.

Proteomic Analysis Identifies Epigenetic Modifiers and Potential Negative Regulators of Leukemogenesis KMD6A and SETDB1 to be Induced Post In Vivo Decitabine Exposure in Pediatric AML

Deregulation of epigenetic mechanisms has been associated with AML pathogenesis. In an integrated transcriptomic and DNA methylation evaluation in pediatric AML, we demonstrated that reduced methylation and increased expression of DNMT3B were associated with greater genome-wide methylation and worse outcome in pediatric AML patients treated on St Jude AML02 and COG clinical trials. This epigenetic deregulation has been leveraged through use of DNA methylation inhibitors (DMTis) such as azacytidine and decitabine for treatment of MDS and AML. Given promising results in adults and relapsed pediatric AML, the multi-site AML16 clinical trial (NCT03164057) evaluated single agent DMTi "priming” followed by standard chemotherapy for the treatment of pediatric AML. Despite the use of DMTi to treat heme-malignancies, the underlying molecular mechanisms are still under investigation. Thus, we evaluated molecular in vivo response of pediatric AML cells to decitabine by evaluating paired specimens obtained at diagnosis and after five days of single agent decitabine therapy for global proteomic profiling. In a pilot study we previously showed modest correlation (10.7%) between transcript and protein levels, suggesting that the transcriptome may not be a reliable surrogate for proteomics in pediatric AML. Additionally, given that the majority of biological functions within cells are operated by proteins and most drugs target the proteome rather than the genome or transcriptome, understanding the proteomic signatures is critical. Thus, in this evaluation, we focused on decitabine-induced alterations in cellular proteomic profiles of paired diagnostic leukemic samples and 5 days post in vivo decitabine exposure from 9 patients treated on AML16. Completely automated high-resolution TMT (tandem-mass-tag) -LC/LC-MS/MS system was utilized to capture high resolution proteomic data and 10,471 proteins were detected in samples. At p<0.01, 109 proteins increased and 41 decreased post decitabine exposure. In vivoexposure to decitabine resulted in increased levels of several epigenetic regulators, including KMD6A and SETDB1. KMD6A, a histone3 lysine 27 demethylase, was recently shown to be mutated in relapsed AML and loss of KMD6A has been associated with resistance to cytarabine and daunorubicin (PMID: 31201358). SETDB1 is a methyltransferase that suppresses leukemogenesis and higher SETB1 expression has been shown to alter the promoter epigenome and reduce expression of AML associated genes such as DOCK1, HOXA9, SIX1. A recent study demonstrated SETDB1 to be negatively regulating pro-leukemic target genes thereby suppressing AML (PMID: 33054052). Among the top genes that were reduced at protein levels was DNMT3A, which is a well-established prognostic marker in adult AML. Combined, alterations in these protein levels suggest that decitabine exposure may increase sensitivity of AML blasts to chemotherapy and interfere with the leukemia program. Of particular interest were proteins that are targetable by drugs and demonstrated increased expression post decitabine exposure such as dihydrofolate reductase (DHFR), which is essential for cellular metabolism and growth. DHFR is inhibited by the antileukemic agent methotrexate and our data suggest that DNMTi priming might increase sensitivity of leukemia cells to methotrexate. Other targetable proteins are listed in Table 1. In summary, this pilot study provides significant insight into the DMTi-mediated proteomics changes that hold prognostic and therapeutic relevance in AML. Ongoing studies are focused on expanding the cohort size and evaluate association of proteomics with clinical outcome. Additionally, we plan to perform a multi-omics analysis by integrating proteomics with DNA methylation, RNAseq and metabolomics. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Screening of Differential DNA Methylation Sites and Signal Pathway Analysis of Juvenile Myelomonocytic Leukemia in Children before and after Decitabine Treatment

Enrolled subjects were 7 children diagnosed with JMML in Nanfang Chunfu Children's Institute Hematology & Oncology Research according to the 2016 WHO standard from January 2019 to July 2020. Bone marrow samples were collected from all 7 children before and after the decitabine treatment. DNA extraction was successfully performed in all 7 cases of before group. And DNA extraction was successfully performed in only 4 cases of after group, while was failed in the rest of 3 cases. 11 DNA samples that were successfully extracted and qualified for quality control (7 cases before treatment, 4 cases after treatment) were subjected to chip experiments according to the Illumina Infinium Methylation EPIC 850K BeadChip manufacture protocol. The BMIQ algorithm is used to standardize methylation level β value. The enrolled cases were divided into two groups before and after treatment with decitabine, and the difference in β value before and after treatment was compared. The criteria for differential screening are: ∣Δβ∣≥0.1, P<0.01. Then through the visualization of DMP display, GO and KEGG function enrichment and related signal pathways, explore the mechanism of demethylation of decitabine in the treatment of JMML. Public database JMML gene expression dataset and independent JMML validation cohort was used for mechanism validation. 1. From the β value density curve and box plot, it can be seen that the β value of JMML children has a "bimodal" pattern, but the density of high methylation sites is significantly higher than that of low methylation sites. Screening for differential methylation sites through the champ. DMP function, a total of 2310 differentially methylated positions that meet the screening criteria were obtained, accounting for 0.26% of the methylation coverage of 850K chip, indicating that demethylation drugs have an effect on the overall high methylation level loci, but number of points does not affected much. Through DMP scatter plots, volcano plots and cluster analysis, it is found that each enrolled child with JMML has a specific abnormally hypermethylation pattern, and demethylation treatment is to reduce the degree of methylation of certain CpG sites under the specific hypermethylation pattern of each patient. 2. Perform GO and KEGG function enrichment analysis on the genes adjacent to the 2310 differentially methylated sites that have been screened out. In the GO enrichment analysis, it is found that the activity of PI3K/AKT pathway showed the highest adjacent gene enrichment with significant P value(Figure 1.A). In the KEGG enrichment analysis(Figure 1.B), it is found that DMP has the highest degree of enrichment in genes that affect signal transduction, indicating that demethylation therapy has the greatest impact on the signal transduction process within/between the signal pathway. Combined with the results of GSEA, it is suggested that decitabine may reduce the methylation of some related genes in the PI3K/AKT signaling pathway near the CpG site, thereby inhibiting the abnormal activation of the PI3K/AKT signaling pathway, so as to achieve the effect of treating JMML. In the validation cohort, it was confirmed that the expression of phosphorylated PI3K/AKT protein was significantly decreased after decitabine treatment compared with before treatment. 3. A total of 5 motifs were obtained by motif analysis, and these motifs correspond to a total of 22 transcription factors, namely INSM1, SP1, T, EBF1, Egr1, EWSR1-FLI1, FEV Hand1::Tcfe2a, IRF1, Klf4, Myf , NFATC2, NFE2L2, NHLH1, PPARG::RXRA, RXR::RAR_DR5, SPI1, Spz1, Stat3, Tal1::Gata1, TFAP2A, Zfp423; the upstream transcription factors of the target genes DNMT1, DNMT3A and DNMT3B of decitabine. The 165 possible transcription factors were intersected with the transcription factors corresponding to the motif analysis, and the common transcription factor was the RXRA gene. GSE71935 dataset in the GEO contains gene expression data of 38 JMML patients and 9 normal healthy controls, confirming that JMML patients have decreased RXRA gene expression and increased DNMT3A and DNMT3B expression relative to healthy donors group(Figure 1.C/D). Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Mediterranean G6PD variant mitigates expression of DNA methyltransferases and right heart pressure in experimental model of pulmonary hypertension

DNA methylation potentially contributes to the pathogenesis of pulmonary hypertension (PH). However, the role of DNA methyltransferases (DNMTs: 1, 3a, and 3b), the epigenetic writers, in modulating DNA methylation observed in PH remains elusive. Our objective was to determine DNMT activity and expression in the lungs of experimental rat models of PH. Because the activity of DNMTs is metabolically driven, another objective was to determine the role of glucose-6-phosphate dehydrogenase (G6PD) in regulating DNMT expression and activity in the lungs of novel loss-of-function Mediterranean G6PD variant (G6PDS188F) rats. As outlined for modeling PH, rats injected with sugen5416 (SU) were placed in a hypoxia (Hx) chamber set at 10% oxygen for 3weeks and then returned to normoxia (Nx) for 5weeks (SU/Hx/Nx). Rats kept in atmospheric oxygen and treated with SU were used as controls. We assessed the activity and expression of DNMTs in the lungs of rats exposed to SU/Hx/Nx. WT rats exposed to SU/Hx/Nx developed hypertension and exhibited increased DNMT activity and Dnmt1 and Dnmt3b expression. In G6PDS188F rats, which developed less of a SU/Hx/Nx-induced increase in right ventricle pressure and hypertrophy than WT rats, we observed a diminished increase in expression and activity of DNMTs, DNA hypomethylation, increased histone acetylation and methylation, and increased expression of genes encoding NOS3 and SOD2-vascular-protective proteins. Collectively, increased DNMTs contribute to reduced expression of protective genes and to the pathogenesis of SU/Hx/Nx-induced experimental PH. Notably, G6PD regulates the expression of DNMTs and protective proteins in the lungs of hypertensive rats.

HDAC2 Induces DNA Methyltransferase DNMT3B Expression to Regulate the Wnt Signaling Pathway and Thus Promotes Glioma Development and Progression.

Purpose To investigate the role and molecular mechanism of HDAC2 in glioma. Methods GSE16011, GSE31262, and GSE90598 datasets were used to identify co-expressed genes, GO analysis, and KEGG analysis to identify gene enrichment pathways, and PPI networks were constructed to identify gene interrelationships. HDAC2 enrichment on DNMT3B promoter and DNMT3B enrichment on Bcl2 CpG island was detected by a ChIP assay. The expression, prognosis, and hierarchical distribution of HDAC2, DNMT3B, and Bcl2 were examined in the CGGA database, and the correlation between HDAC2 and DNMT3B, Bcl2, and DNMT3B and Bcl2 was assessed. Results The HDAC2-DNMT3B-Bcl2 axis is differentially expressed and interacts in gliomas. HDAC2 activates the transcriptional activity of DNMT3B, and DNMT3B inhibits the expression of Bcl2. HDAC2 and DNMT3B are highly expressed in gliomas and have a poor prognosis, while Bcl2 is lowly expressed in gliomas and has a good prognosis. Conclusion HDAC2 promotes DNMT3B transcriptional repression of Bcl2 expression and Wnt pathway activity, thereby activating glioma cell activity in vitro and in vivo.

Downregulation of ELAVL1 attenuates ferroptosis-induced neuronal impairment in rats with cerebral ischemia/reperfusion via reducing DNMT3B-dependent PINK1 methylation.

Ferroptosis is a non-apoptotic form of programmed cell death and has been found in ischemic stroke. Increasing evidence revealed that ELAVL1 is associated with ferroptosis, but it remains largely unclear whether ELAVL1 is involved in ischemic stroke. Here, we aimed to investigate the biological role and mechanism of ELAVL1 in cerebral ischemia/reperfusion (I/R) injury. ELAVL1 shRNA were intravenously injected into rat brain, and then ischemic/reperfusion (I/R) model was constructed in rats to detect infarct volume, neurobehavioral deficit, and several ferroptosis factors (GSH, GPX4, SLC7A11, MDA, ROS, iron ion) in vivo. Oxygen-glucose deprivation/reperfusion (OGD/R) treated pheochromocytoma-12 (PC12) cells were used as in vitro models of I/R. RIP, biotin pull-down and ChIP assays was used to explore the relationship among ELAVL1, DNMT3B, and PINK1. ELAVL1 was highly expressed in rat brain tissue after I/R injury. Compared with those in the I/R group, the injection of RSL3 (30mg/kg) or ferrostatin-1 (10mg/kg) aggravated or alleviated infarct volume, neurobehavioral impairments, and increased or decreased ferroptosis factor levels, respectively. ELAVL1 silencing ameliorated brain damage in I/R-treated rats by inhibiting ferroptosis. Moreover, ELAVL1 silencing observably facilitated cell viability, GSH content, GPX4 and SLC7A11 expression, and reduced iron ion concentration, ROS and MDA levels in OGD/R-treated PC12 cells. ELAVL1 bound with DNMT3B mRNA 3'UTR and promoted DNMT3B expression. ELAVL1 inhibited PINK1 expression through stabilizing DNMT3B mRNA and blocking DNMT3B-mediated DNA methylation of PINK1 promoter. PINK1 knockdown reversed the effects of ELAVL1 inhibition on cell viability, GSH, GPX4, SLC7A11, iron ion concentration, ROS and MDA levels in OGD/R-treated PC12 cells. ELAVL1 plays a critical role in protecting against ferroptosis-induced cerebral I/R and subsequent brain damage via DNMT3B/PINK1 axis, thus providing a new potential target for ischemic stroke treatment.

Comprehensive analysis of m6A/m5C/m1A-related gene expression, immune infiltration, and sensitivity of antineoplastic drugs in glioma.

This research aims to develop a prognostic glioma marker based on m6A/m5C/m1A genes and investigate the potential role in the tumor immune microenvironment. Data for patients with glioma were downloaded from The Cancer Genome Atlas (TCGA) and Chinese Glioma Genome Atlas (CGGA). The expression of genes related to m6A/m5C/m1A was compared for normal and glioma groups. Gene Ontology and Kyoto Encyclopedia of Genes and Gene enrichment analysis of differentially expressed genes were conducted. Consistent clustering analysis was performed to obtain glioma subtypes and complete the survival analysis and immune analysis. Based on TCGA, Lasso regression analysis was used to obtain a prognostic model, and the CGGA database was used to validate the model. The model-based risk scores and the hub genes with the immune microenvironment, clinical features, and antitumor drug susceptibility were investigated. The clinical glioma tissues were collected to verify the expression of hub genes via immunohistochemistry. Twenty genes were differentially expressed, Consensus cluster analysis identified two molecular clusters. Overall survival was significantly higher in cluster 2 than in cluster 1. Immunological analysis revealed statistically significant differences in 26 immune cells and 17 immune functions between the two clusters. Enrichment analysis detected multiple meaningful pathways. We constructed a prognostic model that consists of WTAP, TRMT6, DNMT1, and DNMT3B. The high-risk and low-risk groups affected the survival prognosis and immune infiltration, which were related to grade, gender, age, and survival status. The prognostic value of the model was validated using another independent cohort CGGA. Clinical correlation and immune analysis revealed that four hub genes were associated with tumor grade, immune cells, and antitumor drug sensitivity, and WTAP was significantly associated with microsatellite instability(MSI). Immunohistochemistry confirmed the high expression of WTAP, DNMT1, and DNMT3B in tumor tissue, but the low expression of TRMT6. This study established a strong prognostic marker based on m6A/m5C/m1A methylation regulators, which can accurately predict the prognosis of patients with gliomas. m6A/m5C/m1A modification mode plays an important role in the tumor microenvironment, can provide valuable information for anti-tumor immunotherapy, and have a profound impact on the clinical characteristics.

Distinct global DNA methylation and NF-κB expression profile of preimplantation biopsies from ideal and non-ideal kidneys.

Epigenetic mechanisms may affect the ideal and non-ideal kidneys selected for transplantationand their inflammatory gene expression profile differently and may contribute to poor clinical outcomes. Study the Global DNA methylation and the expression profiles of the DNA methyltransferases (DNMTs) and nuclear factor kappa B (NF-κB) in preimplantation kidney biopsies from ideal and non-ideal kidneys (expanded criteria donor (ECD) and with KDPI > 85%). In a sample consistingof45 consecutive pre-implantation biopsies,global DNA methylation levels were detected by LINE-1 repeated elements using bisulfite pyrosequencing. DNMT gene expression was assessed by real-time quantitative polymerase chain reaction, and NF-κB protein expression by immunofluorescence. ECD kidneys displayed increased methylation levels in LINE-1, and DNMT1 and DNMT3B expression was upregulated when comparing ECD to standard criteria donor kidneys. Similarly, kidneys with KDPI > 85% exhibited increased LINE-1 methylation and DNMT1 upregulation when compared to a KDPI ≤ 85%. NF-κB protein expression levels were greatly increased in both types of non-ideal kidneys compared to ideal kidneys. Moreover, hypermethylation of LINE-1 was associated with cold ischemia time > 20h and ECD kidney classification. This study shows that global DNA hypermethylation and high expression of NF-κB occurred in both types of non-ideal kidneys and were associated with prolonged cold ischemia time. Global DNA methylation can be a useful tool to assess non-ideal kidneys and hence, could be used to expand the pool of kidneys donors.

P2.11: Distinct Global DNA Methylation and NF-κB Expression Profile of Preimplantation Biopsies From Ideal and Non-ideal Kidneys

Background: Epigenetic mechanisms may differently affect the ideal and non-ideal kidneys and their inflammatory gene expression profile and may contribute to poor clinical outcomes. Objective: To identify the Global DNA methylation was evaluated, as well as the expression profiles of the DNA methyltransferases (DNMTs) and nuclear factor kappa B (NF-κB) in preimplantation kidney biopsies from ideal and non-ideal kidneys (extended criteria donor-ECD and with KDPI>85%). Methods: Global DNA methylation was estimated by LINE-1 repeated elements methylation using bisulfite pyrosequencing, DNMTs expression was assessed by q-PCR and NF-κB protein expression by immunofluorescence. Results: ECD kidneys displayed increased methylation levels in LINE-1, and DNMT1 and DNMT3B expression were upregulated when comparing ECD to standard criteria donor kidneys. Similarly, kidneys with KDPI > 85% exhibited increased LINE-1 hypermethylation and DNMT1 upregulation vs. kidneys with a KDPI ≤ 85%. NF-κB protein expression levels were greatly increased in both types of non-ideal kidneys compared to ideal kidneys. Moreover, hypermethylation of LINE-1 was associated with cold ischemia time > 20 h and ECD kidney classification. Conclusions: This study shows that global DNA hypermethylation and high expression of NF-κB occurred in both types of non-ideal kidneys and were associated with prolonged cold ischemia time. Global DNA methylation can be a useful tool to assess suboptimal kidneys and hence, could be used to increase the use of these kidneys to expand the donor pool. This study was supported by São Paulo State Research Foundation (FAPESP – Fundação de Amparo à Pesquisa do Estado de São Paulo) grant number 2016/08301-8.

Associationof vitamin B12/ferritin deficiencyin cancer patients with methylomic changes at promotors of TETmethylcytosine dioxygenases.

Aim: To investigate potential DNA methylation in methylcytosine dioxygenases and correlation of TET genes with vitamin B12/ferritin levels in cancer patients. Materials & methods: 200 blood samples were obtained from both cancer patients and healthy individuals. Results: The expression of DNMT1, DNMT3a and DNMT3b was increased in patients with low vitamin B12 and ferritin levels, while the expression of MTR, TET1 and TET3 significantly decreased. DNA methylation analysis in patients with deficient vitamin B12/ferritin levels showed methylomic changes within the location 318/CG and 385/CG in the promoter region of TET1 and TET3, respectively. Conclusion: Vitamin B12/ferritin deficiency contributes to DNA methylation progress in cancer patients.

LncRNA-ZFAS1 Promotes Myocardial Ischemia-Reperfusion Injury Through DNA Methylation-Mediated Notch1 Down-Regulation in Mice

The most devastating and catastrophic deterioration of myocardial ischemia-reperfusion injury (MIRI) is cardiomyocyte death. Here we aimed to evaluate the role of lncRNA-ZFAS1 in MIRI and delineate its mechanism of action. The level of lncRNA-ZFAS1 was elevated in MIRI hearts, and artificial knockdown of lncRNA-ZFAS1 in mice improved cardiac function. Notch1 is a potential target of lncRNA-ZFAS1, and lncRNA-ZFAS1 could bind to the promoter region of Notch1 and recruit DNMT3b to induce Notch1 methylation. Nicotinamide mononucleotide could promote the expression of Notch1 by competitively inhibiting the expression of DNMT3b and improving the apoptosis of cardiomyocytes and cardiac function.

The epigenetic impact of suberohydroxamic acid and 5‑Aza‑2'‑deoxycytidine on DNMT3B expression in myeloma cell lines differing in IL‑6 expression.

Gene inactivation of the cyclin-dependent kinase inhibitors p16INK4a, p15INK4b and p21WAF is frequently mediated by promoter gene methylation, whereas histone deacetylases (HDACs) control gene expression through their ability to deacetylate proteins. The effect of suberohydroxamic acid (SBHA) and 5-Aza-2′-deoxycytidine (Decitabine) (DAC) treatments on the transcription of CDKN2A, CDKN2B and CDKN1A genes, and their effects on molecular biological behavior were examined in two myeloma cell lines, RPMI8226 and U266, which differ in p53-functionality and IL-6 expression. In both tested myeloma cell lines, a non-methylated state of the CDKN2B gene promoter region was detected with normal gene expression, and the same level of p15INK4b protein was detected by immunocytochemical staining. Furthermore, in myeloma cells treated with SBHA and DAC alone, the expression of both p15INK4b and p21WAF was significantly upregulated in RPMI8226 cells (p53-functional, without IL-6 expression), whereas in the U266 cell line (p53 deleted, expressing IL-6) only p21WAF expression was significantly increased. Moreover, the analysis revealed that treatment with DAC induced DNMT3B enhancement in U266 cells. In conclusion, in myeloma cells with IL-6 expression, significantly increased DNMT3B expression indicated the tumorigenic consequences of 5-Aza-2′deoxycytidine treatment, which requires careful use in diseases involving epigenetic dysregulation, such as multiple myeloma (MM).

Abstract P3102: Matrine Inhibits Advanced Glycation End Products- Inducedmatrine Inhibits Advanced Glycation End Products- Induced Macrophage M1 Polarization By Reducing Dnmt3a/b- Mediated Dna Methylation Of Gpx1 Promoter

Background and Objective: Advanced glycation end products (AGEs) are characterized diabetic metabolites inducing macrophage M1 polarization which is crucial in diabetes- exacerbated atherosclerosis. Matrine was proved anti-atherosclerotic. The current study was aimed to investigate the inhibitory effects of matrine on AGEs- induced macrophage M1 polarization and underlying molecular mechanisms. Methods: Primary mouse macrophages were exposed to AGEs. Receptor for AGEs (RAGE) and toll-like receptor 4 (TLR4) were over-expressed by vectors. Matrine was used to treat these cells. Inducible nitric oxide synthase (iNOS) expression and pro-inflammatory cytokine production were used to evaluate macrophage M1 polarization. Oxidative stress was assessed by intracellular reactive oxygen species (ROS) generation, total antioxidant capacity (TAC) and malondialdehyde (MDA) contents. Relative mRNA expression level was determined by real-time PCR. Western blotting was used to evaluate protein and protein phosphorylation levels. Bisulfite sequencing PCR (BSP) was used to evaluate DNA methylation. Results: Matrine inhibited AGEs- induced macrophage M1 polarization which was impaired by RAGE and TLR4 over-expressions. Matrine reduced AGEs exposure elevated expressions of DNMT3a and DNMT3b in macrophages, which further decreased DNA methylation of GPX1 promoter. Increased GPX1 by matrine suppressed oxidative stress in AGEs- exposed macrophages which was impaired by RAGE over-expression. Conclusions: Matrine inhibited AGEs- induced macrophage M1 polarization by suppressing RAGE-induced oxidative stress-mediated TLR4/STAT1 signaling pathway. Matrine exerted anti-oxidant effects via increasing GPX1 expression by inhibiting DNMT3a/b- induced GPX1 promoter DNA methylation.

Mechanisms of immune evasion by head and neck cancer stem cells.

Different mechanisms are involved in immune escape surveillance driven by Oral and Head and Neck Cancer Stem Cells (HNCSCs). The purpose of this review is to show the most current knowledge regarding the main impact of HNCSCs on tumor evasion through immunosuppression, CSCs phenotypes and environmental signals, highlighting strategies to overcome immune evasion. The main results drive the participation of cell surface receptors and secreted products and ligands, the crosstalk between cells, and genetic regulation. The reduction in CD8+ T cell recruitment and decreased effector of anti-PD-1 therapy by cells expressing BMI1 is a key event; Natural Killer cell ligands and cytokines needed for its activation and expansion are crucial to control tumor growth and to target CSCs by immunotherapy; CSCs expressing ALDH1 are related to increased expression of PD-L1, with a positive link between DNMT3b expression; CD276 expression in CSCs can act as a checkpoint inhibitor and together with Activator Protein 1 (AP-1) activation, they create continuous positive feedback that enables immune evasion by suppressing CD8+ T cells and prevent immune cell infiltration in head and neck cancer. These data demonstrate the relevance of the better understanding of the interaction between HNCSCs and immune cells in the tumor microenvironment. The ultimate clinical implication is to ground the choice of optimized targets and improve immune recognition for ongoing treatments as well as the response to approved immunotherapies.