Objective
To investigate the tumor suppressor genes of phlegm DNA in smokers, and analyze the correlation between methylation level of tumor suppressor gene promoter and chronic mucus hypersecretion (CMH).
Methods
The study recruited the patients who were admitted in the respiratory department during 2013-2016 in this hospital, including 700 cases of urban smokers and 380 cases of rural smokers. Eleven genes commonly silenced by promoter methylation in lung cancer and associated with cancer risk were selected. Methylation specific PCR (MSP) was used in the sputum sample of 700 individuals in the urban smokers cohort. Replication was performed in 380 individuals from the rural smokers cohort.
Results
CMH was significantly associated with an overall increased number of methylated genes, with SULF2 methylation demonstrating the most consistent association. The association between SULF2 methylation and CMH was significantly increased in males but not in females both in the urban and rural groups (OR=2.73, 95%CI 1.53-4.93, P=0.001; OR=2.96, 95%CI 1.47-5.94, P=0.002, respectively). Furthermore, the association between methylation and CMH was more obvious among 139 male former smokers with persistent CMH compared with current smokers (SULF2, OR=3.64, 95%CI 1.57-8.35, P=0.002).
Conclusion
These findings demonstrate that especially male former smokers with persistent CMH have markedly increased promoter methylation of lung cancer risk genes and potentially could be at increased risk for lung cancer.
DNA 甲基化可通過調節基因轉錄水平的表達改變，在突觸重塑、神經前體細胞分化等神經生物過程中起重要作用。近年來，不斷有研究發現，DNA 甲基化與癲癇密切相關。文章主要探討 DNA 甲基化參與癲癇發病的可能機制，以及為 DNA 甲基化提供甲基的甲硫氨酸循環在癲癇發病機制中的調控作用，以期為癲癇的預防和治療提供新思路。
ObjectiveTo explore the accuracy of machine learning algorithms based on SHOX2 and RASSF1A methylation levels in predicting early-stage lung adenocarcinoma pathological types. MethodsA retrospective analysis was conducted on formalin-fixed paraffin-embedded (FFPE) specimens from patients who underwent lung tumor resection surgery at Affiliated Hospital of Nantong University from January 2021 to January 2023. Based on the pathological classification of the tumors, patients were divided into three groups: a benign tumor/adenocarcinoma in situ (BT/AIS) group, a minimally invasive adenocarcinoma (MIA) group, and an invasive adenocarcinoma (IA) group. The methylation levels of SHOX2 and RASSF1A in FFPE specimens were measured using the LungMe kit through methylation-specific PCR (MS-PCR). Using the methylation levels of SHOX2 and RASSF1A as predictive variables, various machine learning algorithms (including logistic regression, XGBoost, random forest, and naive Bayes) were employed to predict different lung adenocarcinoma pathological types. ResultsA total of 272 patients were included. The average ages of patients in the BT/AIS, MIA, and IA groups were 57.97, 61.31, and 63.84 years, respectively. The proportions of female patients were 55.38%, 61.11%, and 61.36%, respectively. In the early-stage lung adenocarcinoma prediction model established based on SHOX2 and RASSF1A methylation levels, the random forest and XGBoost models performed well in predicting each pathological type. The C-statistics of the random forest model for the BT/AIS, MIA, and IA groups were 0.71, 0.72, and 0.78, respectively. The C-statistics of the XGBoost model for the BT/AIS, MIA, and IA groups were 0.70, 0.75, and 0.77, respectively. The naive Bayes model only showed robust performance in the IA group, with a C-statistic of 0.73, indicating some predictive ability. The logistic regression model performed the worst among all groups, showing no predictive ability for any group. Through decision curve analysis, the random forest model demonstrated higher net benefit in predicting BT/AIS and MIA pathological types, indicating its potential value in clinical application. ConclusionMachine learning algorithms based on SHOX2 and RASSF1A methylation levels have high accuracy in predicting early-stage lung adenocarcinoma pathological types.
Objective To investigate the effects of DNA methyltransferase inhibitor (DNMTi) and histone deacetylase inhibitor (HDCAi) on expression of E-cadherin gene and invasiveness of cholangiocarcinoma cell. Methods According to different treatment, the QBC939 cells were divided into four groups: blank control group, hydralazine group, valproic acid group and hydralazine and valproic acid combined group. After 48 h, the expression of E-cadherin was evaluated by reverse transcription-PCR (RT-PCR), mehtylation specific PCR (MSP) and Western blot, the invasiveness of QBC939 cells was evaluated by Transwell method. Results There was no expression of E-cadherin mRNA and protien in blank control group and valproic acid group. The expressions of E-cadherin mRNA and protien in hydralazine and valproic acid combined group were higher than those in hydralazine group ( P ＜ 0.01), while the invasiveness of QBC939 cells of hydralazine and valproic acid combined group was much lower than that of blank control group, hydralazine group and valproic acid group ( P ＜ 0.01). Conclusion DNMTi and HDACi can synergistically re-express E-cadherin gene and weaken the invasiveness of QBC939 cell, which plays an important part in treatment of cholangiocarcinoma.
DNA 甲基化是人類發現最早的表觀遺傳學修飾之一，具有多種調控功能，參與機體發育過程中干細胞生長、細胞增殖、器官發育、衰老和腫瘤發生等多個生物學過程，而且在突觸重塑、神經細胞分化等神經生物過程中也具有重要作用。近年來，越來越多的研究表明 DNA 甲基化修飾與癲癇的發病機制密切相關，特別是基因啟動子的甲基化改變逐漸受到關注。文章主要對表觀遺傳中基因啟動子區的甲基化在癲癇發生發展中的研究進展進行綜述。
ObjectiveTo explore the effects and molecular mechanisms of histone methylase G9a inhibitor BIX-01294 on apoptosis in esophageal squamous cell carcinoma (ESCC).MethodsMTT assay and Colony-forming Units were adopted to determine the effects of BIX-01294 on the growth and proliferation of ESCC cell lines EC109 and KYSE150. Flow cytometry was used to analyze the apoptosis status of ESCC cells after the treatment of BIX-01294. The effects of BIX-01294 treatment on the expressions of G9a catalytic product H3K9me2, DNA double-strand break (DSB) markers, and apoptosis-related proteins were detected by Western blotting.ResultsBIX-01294 inhibited the growth of EC109 and KYSE150 cells in a dose-dependent manner (P<0.05), and BIX-01294 with the inhibitory concentration 50% (IC50) significantly inhibited the formation of colony (P<0.05). After 24 hours treatment of BIX-01294 (IC50), the apoptosis rate of EC109 cells increased from 11.5%±2.1% to 42.5%±5.4%, and KYSE150 cells from 7.5%±0.9% to 49.2%±5.2% (P<0.05). The expression level of the G9a catalytic product, H3K9me2, significantly decreased (P<0.05); while the expression of the DSB marker γH2AX was dramatically enhanced (P<0.05). We also found that the mitochondrial apoptosis pathway was activated and the expression levels of cleaved caspase3 and cleaved PARP were significantly elevated (P<0.05).ConclusionBIX-01294, the inhibitor of methyltransferase G9a, prompted apoptosis in ESCC cells by inducing DSB damage and activating mitochondrial apoptosis pathway.
ObjectiveTo explore the relationship between aberrant promoter CpG islands methylation status of E-cadherin gene and hepatocarcinogenesis, and to assess its significance in clinical early diagnosis of hepatocellular carcinoma (HCC). MethodsSurgically resected specimens, among which cancerous and corresponding noncancerous liver tissues from 34 HCC patients, 10 liver cirrhosis from patients without HCC and normal liver tissues from 4 accidental deaths, were collected in West China Hospital. Breast cancer cell line MDA-MB-435 with promoter CpG islands hypermethylation of E-cadherin as positive control was gained from the Cell Bank of Chinese Academy of Sciences in Shanghai. The methylation status of promoter CpG island of E-cadherin gene was detected by nested methylationspecific polymerase chain reaction (nested-MSP). ResultsE-cadherin gene promoter CpG islands hypermethylation was found in 61.76% (21/34) of cancerous tissues, in 29.41% (10/34) of noncancereous tissues from the 34 HCC patients and in 50.00% (5/10) liver cirrhosis from patients without HCC. None of the 4 normal liver samples were detected E-cadherin mehylation positive. Moreover, the methylation of E-cadherin gene was significantly more frequent in 34 cancerous than that in corresponding noncancerous liver tissues (Plt;0.05), which had no significant difference between the 10 cirrhotic samples and cancerous or non-cancerous liver tissues (Pgt;0.05). In 34 cancerous samples, with the combination of both biomarkers of E-cadherin methylation and AFP400 (serum AFP level at a cutoff of 400 μg/L), the diagnostic sensitivity of HCC increased to 82.35%. ConclusionsThe aberrant promoter methylation of E-cadherin gene may play a vital role in the development and progression of HCC. Moreover, it might be an early event in hepatocarcinogensis. It is of high value to make further study to confirm the significance of E-cadherin gene methylation in clinical diagnosis and therapy.
Recent advances in epigenetics indicate that several epigenetic modifications, including acetylation, methylatio, and microRNA (miRNA), play an important role in the pathogenesis of acute kidney injury (AKI). Our study reveales that enhancement of protein acetylation by pharmacological inhibition of class I histone deacetylases leads to more severe tubular injury, and delays the restoration of renal structure and function. The changes in promoter DNA methylation occurs in the kidney with ischemia/reperfusion. MiRNA expression is associated with the regulation of both renal injury and regeneration after AKI. Targeting the epigenetic process may provide a therapeutic treatment for patients with AKI. The purpose of this review is to summarize recent advances in epigenetic regulation of AKI and provide mechanistic insight into the role of acetylation, methylation, and miRNA expression in the pathological processes of AKI.
