• 제목/요약/키워드: DNA methyltransferase 3a

검색결과 53건 처리시간 0.018초

Role of P14 and MGMT Gene Methylation in Hepatocellular Carcinomas: a Meta-analysis

  • Li, Cheng-Cheng;Yu, Zhuang;Cui, Lian-Hua;Piao, Jin-Mei;Liu, Meng
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제15권16호
    • /
    • pp.6591-6596
    • /
    • 2014
  • Background: This meta-analysis was performed to investigate the relationship between methylation of the P14 and O6-methylguanine-DNA methyltransferase (MGMT) genes and the risk of hepatocellular carcinoma (HCC). Materials and Methods: We searched PubMed, EMBASE, the Chinese Biomedical Database (CBM), and the China National Knowledge Infrastructure (CNKI) databases to identify relevant studies that analysed HCC tissues for P14 and MGMT gene methylation status; we then performed a meta-analysis. Odds ratios (ORs) and 95% confidence intervals (95%CIs) were calculated to evaluate the association between gene methylation and the risk of HCC. Results: Ten studies that assessed P14 gene methylation in 630 HCC tumour tissues and nine studies analysing MGMT methylation in 497 HCC tumour tissues met our inclusion criteria. Our meta-analysis revealed that the rate of P14 methylation was significantly higher in HCCs than in adjacent tissues (OR 3.69, 95%CI 1.63-8.35, p=0.002), but there was no significant difference in MGMT methylation between HCC and adjacent tissues (OR 1.76, 95%CI 0.55-5.64, p=0.34). A subgroup analysis according to ethnicity revealed that P14 methylation was closely related to the risk of HCC in Chinese and Western individuals (Chinese, OR 7.74, 95%CI 1.36-44.04, p=0.021; Western, OR 3.60, 95%CI 1.49-8.69, p=0.004). Furthermore, MGMT methylation was not correlated with the risk of HCC in Chinese individuals (OR 2.42, 95%CI 0.76-7.73, p=0.134). The combined rate of P14 methylation was 35% (95%CI 24-48%) in HCC tumour tissues and 11% (95%CI 4-27%) in adjacent tissues, whereas the combined rate of MGMT methylation was 15% (95%CI 6-32%) in HCC and 10% (95%CI 4-22%) in adjacent tissues. Conclusions: These results suggest that the risk of HCC is related to P14 methylation, but not MGMT methylation. Therefore, P14 gene methylation may be a potential biomarker for the diagnosis of HCC.

침자극에 대한 반응과 비반응군 흰쥐의 특이 유전자 발현 연구 (Gene Expression Profile of the Responder vs. the Non-Responder to the Acupuncture Mediated Analgesic Effects)

  • 서영찬;노삼웅;이기석;고은정;홍무창;신민규;민병일;배현수
    • 동의생리병리학회지
    • /
    • 제17권3호
    • /
    • pp.633-642
    • /
    • 2003
  • A pain is the symptom which defends against noxious stimulus about a human body, it is known that if the periphery of perceptive nerve were stimulated by a physical or chemical factors, the stimulation is induced by transmission to pain center in the cerebral cortex according to pain conduction tract. The treatment of pain is to decrease a stimulus that causes a pain or block off a nerve transmitting a stimulus or puts on a way to calm down pain center, but It is for adjustment of a pain to be the most representative in acupuncture among various ways to cure a pain in Oriental medicine. However, the analgesic effect of an individual response to acupuncture stimulation shows marked individual variations, so these days genetic a few approach is attempted. On this the author determined that the responding group was appointed those whose tail flick latency (TFL) responding time delayed the minimum of 30 % comparing with basal reaction time. For those whose TFL time had shorter than 30 % was grouped as a non-responding group. And then the hypothalamus of each group was dissected and RNA was further purified. After synthesizing cDNA using oligo dT primer, products were finally applied to the PCR. The results were as follows; The ratio of responding group to non-responding group was 6:4. Ach T (acetylcholinesterase T subunit), BF-I (Brain factor-I), DBH (Dopamine β-hydroxylase) and PNM (Phosphotidylethanolamine N-Methyltransferase) were revealed significantly in the responding group. Cathepsin B and Tau were revealed significantly in the non-responding group. The PCR results show that Ach T, BF-I, DBH and PNM are expressed abundantly in the responding group, where as cathepsin B and tau are abundant in the non-responding group. These results suggest that the analgesic effect on acupuncture stimulation is related to regulation of neurotransmitter as well as neurodegeration of cerebrum.

20(S)- Protopanaxadiol suppresses hepatic stellate cell activation via WIF1 demethylation-mediated inactivation of the Wnt/β-catenin pathway

  • Chunxue Li ;Yating Zhan ;Rongrong Zhang;Qiqi Tao ;Zhichao Lang ;Jianjian Zheng
    • Journal of Ginseng Research
    • /
    • 제47권4호
    • /
    • pp.515-523
    • /
    • 2023
  • Background: 20(S)-protopanaxadiol (PPD), one of the main components of ginseng, has anti-inflammatory, anti-estrogenic, and anti-tumor activities. It is known that activated hepatic stellate cells (HSCs) are the primary producers of extracellular matrix (ECM) in the liver, and the Wnt/β-catenin pathway participates in the activation of HSCs. We aimed to explore whether PPD inhibits liver fibrosis is associated with the Wnt/β-catenin pathway inactivation. Methods: The anti-fibrotic roles of PPD were examined both in vitro and in vivo. We also examined the levels of Wnt inhibitory factor 1 (WIF1), DNA methyltransferase 1 (DNMT1) and WIF1 methylation. Results: PPD obviously ameliorated liver fibrosis in carbon tetrachloride (CCl4)-treated mice and reduced collagen deposition. PPD also suppressed the activation and proliferation of primary HSCs. Notably, PPD inhibited the Wnt/β-catenin pathway, reduced TCF activity, and increased P-β-catenin and GSK-3β levels. Interestingly, WIF1 was found to mediate the inactivation of the Wnt/β-catenin pathway in PPD-treated HSCs. WIF1 silencing suppressed the inhibitory effects of PPD on HSC activation and also restored α-SMA and type I collagen levels. The downregulation of WIF1 expression was associated with the methylation of its promoter. PPD induced WIF1 demethylation and restored WIF1 expression. Further experiments confirmed that DNMT1 overexpression blocked the effects of PPD on WIF1 expression and demethylation and enhanced HSC activation. Conclusion: PPD up-regulates WIF1 levels and impairs Wnt/β-catenin pathway activation via the downregulation of DNMT1-mediated WIF1 methylation, leading to HSC inactivation. Therefore, PPD may be a promising therapeutic drug for patients with liver fibrosis.