Dataset Information

Expression of Dnmt1, demethylase, MeCP2 and methylation of tumor-related genes in human gastric cancer.

ABSTRACT: AIM:To explore the effect of DNA methyltransferase, demethylase and methyl-CpG binding protein MeCP2 on the expressions and methylation of hMSH2 and proto-oncogene in human gastric cancer. METHODS:Paired samples of primary gastric cancer and corresponding para-cancerous, non-cancerous gastric mucosae were obtained from surgically resected specimens of 28 patients. Transcription levels of Dnmt1, mbd2, MeCP2, p16(INK4A), hMSH2 and c-myc were detected by using real-time PCR or RT-PCR. Promoter methylation of p16(INK4A), c-myc and hMSH2 genes was assayed by methylation-specific PCR (MSP) and sequencing (mapping). Their relationships were analyzed by Fisher's exact test using the software SPSS. RESULTS:The average mRNA level of Dnmt1 gene from cancerous tissue was higher and that of mbd2 gene from cancerous tissue was lower than that from non-cancerous tissue, respectively. mbd2 was lower in cancerous tissue than in non-cancerous tissue in 14 (50.0%) of patients but higher in 3 cases (10.7%) of non-cancerous gastric tissue (P<0.001). c-myc expression was up-regulated in cancer tissues (P<0.05). The up-regulation of mbd2 was found in all patients with hypomethylated c-myc. The transcriptional levels of p16(INK4A) and MeCP2 genes did not display any difference between gastric cancerous and matched non-cancerous tissues. There were down-regulation and hypermethylation of hMSH2 in cancer tissues, and the hypermethylation of hMSH2 coexisted with down-regulated transcription. However, the transcription level of the above genes was not associated with biological behaviours of gastric cancers. CONCLUSION:The up-regulation of proto-oncogene may be the consequence of epigenetic control of gene expression by demethylase, and mbd2 is involved in the regulation of hMSH2 expression in human gastric cancer.

SUBMITTER: Fang JY

PROVIDER: S-EPMC4576216 | biostudies-literature | 2004 Dec

REPOSITORIES: biostudies-literature

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Expression of Dnmt1, demethylase, MeCP2 and methylation of tumor-related genes in human gastric cancer.

Fang Jing-Yuan JY Cheng Zhong-Hua ZH Chen Ying-Xuan YX Lu Rong R Yang Li L Zhu Hong-Yin HY Lu Lun-Gen LG

World journal of gastroenterology 20041201 23

<h4>Aim</h4>To explore the effect of DNA methyltransferase, demethylase and methyl-CpG binding protein MeCP2 on the expressions and methylation of hMSH2 and proto-oncogene in human gastric cancer.<h4>Methods</h4>Paired samples of primary gastric cancer and corresponding para-cancerous, non-cancerous gastric mucosae were obtained from surgically resected specimens of 28 patients. Transcription levels of Dnmt1, mbd2, MeCP2, p16(INK4A), hMSH2 and c-myc were detected by using real-time PCR or RT-PCR ...[more]

PMID: 15526354

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Dataset Information

Expression of Dnmt1, demethylase, MeCP2 and methylation of tumor-related genes in human gastric cancer.

Publications

Expression of Dnmt1, demethylase, MeCP2 and methylation of tumor-related genes in human gastric cancer.

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