title: DNA-methyltransferase 3B 39179 G > T polymorphism and risk of sporadic colorectal cancer in a subset of Iranian population.
abstract: BACKGROUND
  Epigenetic event is a biological regulation that influences the expression of various genes involved in cancer. DNA methylation is established by DNA methyltransferases, particularly DNAmethyltransferase 3B (DNMT3B). It seems to play an oncogenic role in the creation of abnormal methylation during tumorigenesis. The polymorphisms of the DNMT3B gene may influence DNMT3B activity in DNA methylation and increase the susceptibility to several cancers. These genetic polymorphisms have been studied in several cancers in different populations.
  
  
  METHODS
  In this study, we performed a case-control study with 125 colorectal cancer patients and 135 cancer-free controls to evaluate the association between DNMT3B G39179T polymorphism (rs1569686) in the promoter region and the risk of sporadic colorectal cancer. Up to now, few studies have investigated the role of this gene variant in sporadic colorectal cancer with no familial history. The genotypes of DNMT3B G39179T polymorphism was analyzed by PCR-RFLP.
  
  
  RESULTS
  We found that compared with G allele carriers, statistically the DNMT3B TT genotype (%34) was significantly associated with increased risk of colorectal cancer (adjusted OR, 3.993, 95% CI, 1.726-9.238, P = 0.001). Compared with DNMT3B TT genotype, the GT and GG genotypes had lower risk of developing sporadic colorectal cancer (OR = 0.848, 95% CI = 0.436-1.650).
  
  
  CONCLUSIONS
  Our findings were consistent with that of previously reported case-control studies with colorectal cancer. These results suggest that the DNMT3B G39179T polymorphism influences DNMT3B expression, thus contributing to the genetic susceptibility to colorectal cancer. Further mechanistic studies are needed to unravel the causal molecular mechanisms.
authors.affiliation: Department of Genetics and Molecular Biology, Faculty of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Abdolreza
authors.initials: A
authors.lastname: Daraei
authors.forename: Rasul
authors.initials: R
authors.lastname: Salehi
authors.forename: Faezeh
authors.initials: F
authors.lastname: Mohamadhashem
references.citation: Genes Dev. 2007 Dec 1;21(23):3110-22
references.pmid: 18056424
references.citation: Can J Surg. 1978 May;21(3):206-8
references.pmid: 647507
references.citation: Exp Ther Med. 2010 Mar;1(2):241-250
references.pmid: 22993535
references.citation: Nature. 2002 Apr 4;416(6880):552-6
references.pmid: 11932749
references.citation: Trends Genet. 2000 Apr;16(4):168-74
references.pmid: 10729832
references.citation: J Mol Biol. 1988 Oct 20;203(4):971-83
references.pmid: 3210246
references.citation: Cancer Metastasis Rev. 2004 Jan-Jun;23(1-2):29-39
references.pmid: 15000147
references.citation: Breast Cancer Res. 2004;6(4):R390-4
references.pmid: 15217506
references.citation: Zhonghua Fu Chan Ke Za Zhi. 2005 Nov;40(11):770-4
references.pmid: 16324253
references.citation: Carcinogenesis. 2005 Feb;26(2):403-9
references.pmid: 15528220
references.citation: Biochem Genet. 2007 Apr;45(3-4):155-63
references.pmid: 17318376
references.citation: Cancer Epidemiol. 2010 Jun;34(3):338-44
references.pmid: 20381446
references.citation: Cancer Lett. 2008 Sep 8;268(1):158-65
references.pmid: 18455294
references.citation: Mol Cell Biochem. 2003 Oct;252(1-2):33-43
references.pmid: 14577574
references.citation: Gastroenterology. 2010 Sep;139(3):788-96, 796.e1-6
references.pmid: 20638935
references.citation: Gastroenterol Clin North Am. 2008 Mar;37(1):1-24, v
references.pmid: 18313537
references.citation: Mol Cancer Res. 2004 Jan;2(1):62-72
references.pmid: 14757847
references.citation: Br J Cancer. 2006 Feb 27;94(4):593-8
references.pmid: 16421593
references.citation: Int J Cancer. 2009 Jul 1;125(1):84-90
references.pmid: 19326430
references.citation: Acta Haematol. 2009;122(1):31-5
references.pmid: 19696477
references.citation: Surg Oncol. 1998 Nov-Dec;7(3-4):115-23
references.pmid: 10677163
references.citation: Mol Biol Rep. 2010 Jan;37(1):219-25
references.pmid: 19626461
references.citation: N Engl J Med. 2008 Mar 13;358(11):1148-59
references.pmid: 18337604
references.citation: World J Gastroenterol. 2005 Jun 21;11(23):3623-7
references.pmid: 15962389
references.citation: Asian Pac J Cancer Prev. 2009;10(6):1177-82
references.pmid: 20192608
references.citation: Cell. 1999 Oct 29;99(3):247-57
references.pmid: 10555141
references.citation: J Exp Clin Cancer Res. 2008 Jul 28;27:24
references.pmid: 18662374
references.citation: Cancer Res. 2002 Sep 1;62(17):4992-5
references.pmid: 12208751
references.citation: BMC Med. 2010 Feb 03;8:12
references.pmid: 20128888
references.citation: Gastroenterology. 2008 Oct;135(4):1079-99
references.pmid: 18773902
references.citation: World J Gastroenterol. 2009 Jan 21;15(3):257-63
references.pmid: 19140224
references.citation: World J Gastroenterol. 2008 Apr 14;14(14):2230-4
references.pmid: 18407600
references.citation: J Cell Biochem. 2002;84(2):324-34
references.pmid: 11787061
references.citation: Cancer Epidemiol Biomarkers Prev. 2006 May;15(5):886-91
references.pmid: 16702365