Methylation of the DNA is an important epigenetic (i.e., not associated with alteration in the primary structure of the DNA) phenomenon, which plays important roles in regulation of gene expression, maintenance of genome integrity, and genomic imprinting. Although not only other nucleotides, but also proteins and lipids can be methylated, in the context of the present discussion, “methylation” ...

5-Aza-2'-deoxycytidine (5-Aza-CdR) is currently acknowledged as a demethylation drug, and causes a certain degree of demethylation in a variety of cancer cells, including pancreatic cancer cells. Emodin, a traditional Chinese medicine (TCM), is an effective monomer extracted from rhubarb and has been reported to exhibit antitumor activity in different manners in pancreatic cancer. In the presen...

4 LIST OF PUBLICATIONS AND MANUSCRIPTS 5 LIST OF ABBREVIATIONS 7 INTRODUCTION 8 1. General introduction to cancer 8 2. Tumor suppressor genes 10 2.1 Knudson’s two-hit hypothesis 10 2.2 The tumor suppressor pRb 11 2.3 The tumor suppressor p53 11 2.4 Tumor suppressor genes on chromosome 3, especially on 3p21.3 13 2.5 Examples of chromosome 3p tumor suppressor genes 15 3. Epigenetics 17 3.1 CpG is...

BACKGROUND The promoter of somatostatin (SST), a primary inhibitor of gastrin-stimulated gastric acid secretion, is hypermethylated in 80% of human colon cancers. The aim of the current study was to investigate whether and at what stage promoter hypermethylation of SST is involved in human esophageal carcinogenesis. METHODS SST promoter hypermethylation was examined by real-time methylation-s...

We evaluated the influence of heme oxygenase-1 (HO-1) gene inhibition in myelodysplastic syndrome (MDS) cell line SKM-1 on enhancement of the demethylating effects of decitabine on p15, and explored the possible mechanism. DNMT1 gene expression in SKM-1 cells was silenced by being transfected by a constructed siRNA with liposomes. The proliferation inhibition rates after drug treatment were det...

BACKGROUND Circulating tumor cells (CTCs) are associated with prognosis in a variety of human cancers and have been proposed as a liquid biopsy for follow-up examinations. We show that tumor suppressor and metastasis suppressor genes are epigenetically silenced in CTCs isolated from peripheral blood of breast cancer patients. METHODS We obtained peripheral blood from 56 patients with operable...

BACKGROUND Methylation of regulatory sequences near GSTP1, which encodes the pi class glutathione S-transferase, is the most common epigenetic alteration associated with prostate cancer. We determined whether the quantitation of GSTP1 methylation in histopathologically distinct prostate tissue samples could improve prostate cancer detection. METHODS We used a fluorogenic real-time methylation...

CpG island aberrant methylation is shown to be an important mechanism in gene silencing. The important role of NF-κB in the inflammatory response to H. pylori colonization has been indicated. We investigated the influence of NFKB1 polymorphisms, -94 ins/del (rs28362491) and -449 C>G (rs72696119), on the aberrant gene methylation under H. pylori infection. Gastric mucosal samples were obtained f...

UNLABELLED BACKGROUND An ameloblastoma is a benign odontogenic neoplasm with aggressive behaviour and high recurrence rates. The increased expression of matrix metalloproteinases (MMPs) has been reported in ameloblastomas. In the present study, we hypothesised that epigenetic alterations may regulate MMP expression in ameloblastomas. METHODS We investigated the methylation status of the ge...

BACKGROUND E (epithelial)-cadherin, the cell adhesion molecule also considered a potential invasion/metastasis suppressor, is mutationally inactivated in nearly half of all undifferentiated-scattered (diffuse-type) gastric carcinomas. In addition, silencing of E-cadherin by CpG methylation within its promoter region has been reported in several gastric carcinoma cell lines. We investigated the ...