Gene Promoter CpG Island Methylation Research Articles

Retraction: Zinc sulfate contributes to promote telomere length extension via increasing telomerase gene expression, telomerase activity and change in the TERT gene promoter CpG island methylation status of human adipose-derived mesenchymal stem cells.

Retraction: Zinc sulfate contributes to promote telomere length extension via increasing telomerase gene expression, telomerase activity and change in the TERT gene promoter CpG island methylation status of human adipose-derived mesenchymal stem cells.

Aberrant Methylation of Suppressor of Cytokine Signaling 1 (SOCS1) Gene as a Biomarker for Early Prediction and Diagnosis of Bladder Cancer.

SOCS1 protein, the negative regulatory protein of the Janus kinase (JAK)/signal transducers and activators of transcription (STAT) signaling pathway, may inhibit signaling of JAK-STAT pathway by several cytokines and has tumor suppressor activity. Methylation of CpG island in the promoter region of SOCS1 gene has often been shown to inactivate the SOCS1 gene in certain human cancers. However, the precise role of SOCS1 in bladder cancer is unclear. Two hundred forty-seven patients with BCa and 243 healthy controls were enrolled from Tumour Hospital Affiliated to Harbin Medical University, Hongqi Hospital Affiliated to Mudanjiang Medical University, and Mudanjiang Tumour Hospital from September 2013 to March 2019. The methylation rate in the promoter region of the SOCS1 among all participants were detected using the MassARRAY EpiTYPER system. A ROC curve was set out to analyze SOCS1 gene promoter CpG island methylation for BCa diagnosis. There was a significantly higher methylation rate in BCa compared to controls. Then we assessed the methylation rate of different CpG islands in SOCS1 gene among BCa cases and normal controls. Methylation rate was shown to vary among different CpG islands. The methylation rates of CpG islands were shown to vary among different grades. We observed that the methylation rate of different CpG islands vary according to pathological grades. Our study demonstrates that aberrant methylation of CpG island in the promoter region of SOCS1 gene may be involved in occurrence, progression, and prognosis of BCa and, thus, may serve as an independent diagnosis and prognostic biomarker.

Aging-like Spontaneous Epigenetic Silencing Facilitates Wnt Activation, Stemness, and BrafV600E-Induced Tumorigenesis

We addressed the precursor role of aging-like spontaneous promoter DNA hypermethylation in initiating tumorigenesis. Using mouse colon-derived organoids, we show that promoter hypermethylation spontaneously arises in cells mimicking the human aging-like phenotype. The silenced genes activate the Wnt pathway, causing a stem-like state and differentiation defects. These changes render aged organoids profoundly more sensitive than young ones to transformation by BrafV600E, producing the typical human proximal BRAFV600E-driven colon adenocarcinomas characterized by extensive, abnormal gene-promoter CpG-island methylation, or the methylator phenotype (CIMP). Conversely, CRISPR-mediated simultaneous inactivation of a panel of the silenced genes markedly sensitizes to BrafV600E-induced transformation. Our studies tightly link aging-like epigenetic abnormalities to intestinal cell fate changes and predisposition to oncogene-driven colon tumorigenesis.

Zinc sulfate contributes to promote telomere length extension via increasing telomerase gene expression, telomerase activity and change in the TERT gene promoter CpG island methylation status of human adipose-derived mesenchymal stem cells.

The use of mesenchymal stem cells (MSCs) for cell therapy and regenerative medicine has received widespread attention over the past few years, but their application can be complicated by factors such as reduction in proliferation potential, the senescent tendency of the MSCs upon expansion and their age-dependent decline in number and function. It was shown that all the mentioned features were accompanied by a reduction in telomerase activity and telomere shortening. Furthermore, the role of epigenetic changes in aging, especially changes in promoter methylation, was reported. In this study, MSCs were isolated from the adipose tissue with enzymatic digestion. In addition, immunocytochemistry staining and flow cytometric analysis were performed to investigate the cell-surface markers. In addition, alizarin red-S, sudan III, toluidine blue, and cresyl violet staining were performed to evaluate the multi-lineage differentiation of hADSCs. In order to improve the effective application of MSCs, these cells were treated with 1.5 × 10−8 and 2.99 × 10−10 M of ZnSO4 for 48 hours. The length of the absolute telomere, human telomerase reverse transcriptase (hTERT) gene expression, telomerase activity, the investigation of methylation status of the hTERT gene promoter and the percentage of senescent cells were analyzed with quantitative real-time PCR, PCR-ELISA TRAP assay, methylation specific PCR (MSP), and beta-galactosidase (SA-β-gal) staining, respectively. The results showed that the telomere length, the hTERT gene expression, and the telomerase activity had significantly increased. In addition, the percentage of senescent cells had significantly decreased and changes in the methylation status of the CpG islands in the hTERT promoter region under treatment with ZnSO4 were seen. In conclusion, it seems that ZnSO4 as a proper antioxidant could improve the aging-related features due to lengthening of the telomeres, increasing the telomerase gene expression, telomerase activity, decreasing aging, and changing the methylation status of hTERT promoter; it could potentially beneficial for enhancing the application of aged-MSCs.

Global methylation and promoter-specific methylation of the P16, SOCS-1, E-cadherin, P73 and SHP-1 genes and their expression in patients with multiple myeloma during active disease and remission.

Tumor suppressor gene promoter CpG island methylation is a well-recognized mechanism in cancer pathogenesis, but its role in multiple myeloma (MM) is controversial. The present study investigated the methylation status and expression of P16, suppressor of cytokine signaling 1 (SOCS-1), P73, E-cadherin and Src homology region 2 domain-containing phosphatase 1 (SHP-1), as well as global methylation in patients with MM during active disease and remission. Bone marrow samples were obtained from 43 patients at the Multiple Myeloma Clinic, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán (Mexico City, Mexico) during active disease and remission. Methylation-specific polymerase chain reaction and ELISA were performed on bisulfite-treated or untreated DNA to determine promoter-specific or genomic methylation, respectively. Gene expression was measured using reverse-transcription polymerase chain reaction. The results indicated that SOCS-1 methylation occurred more frequently during active disease than remission [29 vs. 3.2% (P=0.021)] and was associated with more advanced forms of the disease [international staging system (ISS) 3, 16.67% vs. ISS 1, 8.3% (P=0.037)]. SHP-1 methylation during active disease was associated with a lower probability of survival at 39-month follow up (median), 52.5 vs. 87.5% (P=0.025). The percentage of methylation was associated with active disease at remission, but this was not significant. Global hypomethylation at remission was a negative predictor factor for overall survival (OS). The results indicated that methylated P16, SOCS-1 and SHP-1 were associated with clinical variables of poor prognosis in MM, likewise the persistence of global hypomethylation at remission. The negative impact on OS of global hypomethylation at remission must be confirmed in a larger sample. Future studies are necessary to investigate whether patients with global hypermethylation at remission should receive more aggressive treatments to improve their OS.

Differentially expression p21 and p53 in laryngeal squamous cell carcinoma

AbstractObjective:To investigate the role of the methylation of p21 and p53 gene in laryngeal cancer and laryngeal cancer cell line Hep-2.Method: Methylation of p21 and p53 gene were detected by methylation specific PCR(MSP) in 46 cases with paired cancer tissues and adjacent tissues. Hep-2 cell line was treated with 5-azacytidine at different time points, and Hep-2 cell growth was detected using the MTT assay. Hep-2 cell line was treated with 5-azacytidine at different time points, and then apoptosis was detected by the TUNEL assay. The expression difference of p21 mRNA was detected by RT-PCR method before and after intervention. p21 promoter CpG island methylation status was tested by MSP before and after intervention.Result: The incidence was 45.7% of p21 gene promoter CpG island methylation in 46 cases of laryngeal cancer, while methylation rate in adjacent tissues was 10.9%. There were significant differences between cancer tissues and adjacent tissues(P<0.05).The incidence was 6.5% of p53 gene promoter CpG island methylation in 46 cases of laryngeal cancer, while methylation rate was 4.3% in adjacent tissues,no significant difference of p53 gene methylation was found in laryngeal cancer and counterparts adjacent tissues(P>0.05). The effect of Hep-2 proliferation inhibition interfered by 5-azacytidine was gradually increased over time in a time-dependent manner. Meanwhile, interfered by 5-azacytidine increased the apoptosis in a time-dependent manner. After interference by 5-azacytidine, p21 gene is activated. The expression of p21 mRNA was significantly higher. The p21 gene methylation degree in laryngeal cancer cell line Hep-2 was 43.13%±0.79%. After 5-azacytidine intervention, the degree of methylation was obviously decreased and even showed unmethylation.Conclusion:There was p21 gene promoter CpG island hypermethylation in laryngeal cancer and laryngeal cancer cell line Hep-2, which was a molecular event distinguished laryngeal cancer from normal laryngeal tissue. There was p53 gene promoter CpG island hypomethylation in laryngeal cancer and laryngeal cancer cell line Hep-2.Inactivation of the gene may occur by gene mutation forms and others. Demethylation of drug 5-azacytidine can induce p21 gene promoter CpG island demethylation modification, change the regulation of tumor cell cycle genes in cells and promote tumor cell apoptosis.

Hepatitis B virus X protein upregulates DNA methyltransferase 3A/3B and enhances SOCS-1CpG island methylation.

The aim of the present study was to investigate the effect of hepatitis B virus X protein (HBx) on the expression of DNA methyltransferase (DNMT)3A/3B and suppressors of cytokine signaling‑1 (SOCS‑1), as well as promoter CpG island methylation of the SOCS‑1 gene. Stable hepatocyte cell lines expressing the HBx gene (pcDNA‑X/QSG7701) or an empty gene (pcDNA3.0/QSG7701) were established. Reverse transcription quantitative polymerase chain reaction (PCR) was used to detect the mRNA expression levels of DNMT3A/3B and SOCS‑1. Immunohistochemistry was used to detect the protein expression of DNMT3A/3B. Methylation‑specific PCR (MSP) was used to detect the methylation status of the SOCS‑1 gene promoter. The mRNA and protein expression levels of DNMT3A/3B were significantly higher in the pcDNA‑X/QSG7701‑transfected cells, compared with those in the pcDNA3.0/QSG7701 or non‑transfected QSG7701 cells (P<0.05), whereas the relative mRNA expression of SOCS‑1 was significantly lower in the pcDNA‑X/QSG7701 cells compared with the pcDNA3.0/QSG7701 and non‑transfected QSG7701 cells (F=19.6; P<0.05). Western blot analysis showed that the protein expression of SOCS‑1 was significantly lower in the pcDNA‑X/QSG7701 cells, compared with the pcDNA3.0/QSG7701 or non‑transfected QSG7701 cells (F=19.4; P<0.05). The results of the MSP analysis showed that SOCS‑1 promoter region methylation was present only in the pcDNA‑X/QSG7701 cells. The HBV‑X gene upregulated the mRNA and protein expression levels of DNMT3A/3B, downregulated the expression of SOCS‑1 and increased SOCS‑1 gene promoter CpG island methylation. This may provide a potential explanation of the mechanism underlying HBx-associated hepatocellular carcinoma.

Age-associated methylation change of TAP1 promoter in piglet

Diarrhea and edematous disease are two major causes of mortality in postweaning piglets. These conditions lead to huge economic losses in the swine industry. Escherichia coli F18 is the primary causative agent of these two diseases. Transported associated with antigen processing (TAP) plays an important role in the immune response and the TAP1 gene could be an effective anti-E. coli F18 molecular marker in pigs. The aim of this study was to determine the correlation between TAP1 gene promoter CpG island methylation status and mRNA expression in piglets. In this study, bisulfite sequencing PCR (BSP) was used to detect the methylation status of the TAP1 gene promoter CpG islands and fluorescence quantitative PCR was used to detect TAP1 expression in the jejunum of Sutai piglets from birth to weaning age. The fragment of the TAP1 gene promoter region under investigation has no mutation, has 13 putative transcription factor binding sites containing 19 CpG sites, and may be important for regulation of gene expression. With increasing age, the overall methylation levels decreased, while the TAP1 expression levels increased, indicating a negative correlation between TAP1 expression and promoter methylation levels. Variance analysis showed significant differences in the methylation status of CpG_4, CpG_13 and CpG_15 among the different age groups (P<0.05). Our data indicate that TAP1 expression is increased by demethylation of promoter CpG islands, with CpG_4, CpG_13 and CpG_15 implicated as the critical regulatory sites.

Forkhead/winged helix transcription factor P3 gene methylation regulation of regulatory T Cells proliferation and function in murine autoimmune hepatitis

Objective To investingate whether T(Treg) cells forkhead/winged helix transcription factor P3(Foxp3)gene promoter CpG island methylation was participated in the Rhesus rotavirus(RRV) inhibiting regulatory Treg cells in BALB/c mice liver, to explore its role in autoimmune liver inflammation. Methods A total of 60 7-9-week-old BALB/c mice were divided randomly into 3 groups(20 each): injected intraperitoneally PFU= 106 RRV infection 24 h and 48 h,and normal control group injected the same volume of saline.Discontinuous Percoll gradient separation of monocytes, Using flow cytometry sorting liver CD4+ CD25+ Foxp3+ Treg cells.Application bisulfite sequencing method modified after sulphate (BSP) to detect BALB/c mouse spleen tissue carve DNA Foxp3 Treg cells selected gene promoter CpG island methylation status, Western blotting assay, spectrophotometer assay respectively. Results In the control group and after injection RRV 24 h or 48 h, accounted for the proportion of CD4+ cells was (5. 26±0. 21)%,(4. 30±0. 46)%,(3. 60±0. 19)% respectively, and the difference were statistically significance(P< 0. 05).Foxp3 gene CpG island methylation were(2. 78±0. 33)%,(26. 70±1. 87)%, (41. 18±3. 67)% respectively and the difference were statistically significance(P< 0. 01).Expression of Foxp3 Treg cells also decreased, with RRV infection time was positively correlated,and the differences were statistically significant(P< 0. 05). Conclusion RRV significantly promote the Treg cells Foxp3 gene promoter CpG island methylation in BALB/c mice liver,and Inhibit the proliferation of Treg cells and normal immune function.That may involved in autoimmune hepatitis in mice. Key words: Regulatory T Cells; Forkhead/winged helix transcription factor P3 gene; CpG island; Methylation; Autoimmune hepatitis

Promoter CpG island methylation of RET predicts poor prognosis in stage II colorectal cancer patients

Improved prognostic stratification of patients with TNM stage II colorectal cancer (CRC) is desired, since 20–30% of high-risk stage II patients may die within five years of diagnosis. This study was conducted to investigate REarranged during Transfection (RET) gene promoter CpG island methylation as a possible prognostic marker for TNM stage II CRC patients.The utility of RET promoter CpG island methylation in tumors of stage II CRC patients as a prognostic biomarker for CRC related death was studied in three independent series (including 233, 231, and 294 TNM stage II patients, respectively) by using MSP and pyrosequencing. The prognostic value of RET promoter CpG island methylation was analyzed by using Cox regression analysis.In the first series, analyzed by MSP, CRC stage II patients (n = 233) with RET methylated tumors had a significantly worse overall survival as compared to those with unmethylated tumors (HRmultivariable = 2.51, 95%-CI: 1.42–4.43). Despite a significant prognostic effect of RET methylation in stage III patients of a second series, analyzed by MSP, the prognostic effect in stage II patients (n = 231) was not statistically significant (HRmultivariable = 1.16, 95%-CI 0.71–1.92). The third series (n = 294), analyzed by pyrosequencing, confirmed a statistically significant association between RET methylation and poor overall survival in stage II patients (HRmultivariable = 1.91, 95%-CI: 1.04–3.53). Our results show that RET promoter CpG island methylation, analyzed by two different techniques, is associated with a poor prognosis in stage II CRC in two independent series and a poor prognosis in stage III CRC in one series. RET methylation may serve as a useful and robust tool for clinical practice to identify high-risk stage II CRC patients with a poor prognosis. This merits further investigation.

Advances of CpG island methylation phenotypes in gastric cancer

CpG island methylator phenotype (CIMP) refers to a set of multiple gene promoter CpG island methylation phenotype which exists in tumor at the same time.Many studies show that CIMP is ubiquitous in gastric cancer,which is related to the pathogenesis,diagnosis,patient's condition,prognosis and curative effect of gastric cancer. Key words: Stomach neoplasms; Methylation; CIMP

The expression of CDH1 gene methylation in patients with esophagus and stomach double primary carcinoma and its significance

Objective To study the changes of CDH1 gene promoter CpG island methylation and its clinical significance in patients with esophagus and stomach double primary carcinoma(ESDC).Methods The expression of CDH1 gene methylation in cancerous tissues and adjacent cancerous tissues in 18 cases of ESDC were detected using methylation-specific PCR method. Results Eighteen patients were endoscopically diagnosed as ESDC between Jan. 2007 and Sep. 2009 in the 4th Hospital Affiliated to Hebei Medical University. The positive methylation of CDH1 gene in tissues of esophageal squamous cell carcinoma (ESCC)and adjacent cancer were 66.7% and 33. 3%, respectively, with significant difference (χ2= 4. 167, P = 0. 031). Whereas the positive methylation of CDH1 gene in tissues of gastric carcinoma (GA) and adjacent cancer were 77.8% and 44.4%, respectively, without statistical difference (χ2=1.786, P= 0. 180). There was no significant difference (P=0. 500) in positive rate of CDH1 gene methylation between ESCC tissues and GA tissues in same individual with ESDC. For 18 patients with ESDC, consistent change of CDH1 methylation in tissues of two kinds of cancers was found in 16 patients with a total agreement of 88.9 % (positive agreement of 66.7 % and negative agreement of 22. 2%). Statistical analysis showed a significant correlation between two groups (P = 0. 005). Conclusion In patients with ESDC, there is a high consistency of CDH1 methylation change, between ESCC and GA,which suggests that two kinds of cancer may have similar risk factors and molecular mechanisms. Key words: Stomach neoplasms; Esophasus neoplas double primary carcinoma; Esophageal squmaous cell carcinoma; CDH1; Methylatlion