Expression and new exon mutations of the human Beta defensins and their association on colon cancer development

PLoS One. 2015 Jun 3;10(6):e0126868. doi: 10.1371/journal.pone.0126868. eCollection 2015.

Abstract

The development of cancer involves genetic predisposition and a variety of environmental exposures. Genome-wide linkage analyses provide evidence for the significant linkage of many diseases to susceptibility loci on chromosome 8p23, the location of the human defensin gene cluster. Human β-defensins (hBDs) are important molecules of innate immunity. This study was designed to analyze the expression and genetic variations in hBDs (hBD-1, hBD-2, hBD-3 and hBD-4) and their putative association with colon cancer. hBD gene expression and relative protein expression were evaluated by Real-Time polymerase chain reaction (qPCR) and immunohistochemistry, respectively, from 40 normal patients and 40 age-matched patients with colon cancer in Saudi Arabia. In addition, hBD polymorphisms were genotyped by exon sequencing and by promoter methylation. hBD-1, hBD-2, hBD-3 and hBD-4 basal messenger RNA expression was significantly lower in tumor tissues compared with normal tissues. Several insertion mutations were detected in different exons of the analyzed hBDs. However, no methylation in any hBDs promoters was detected because of the limited number of CpG islands in these regions. We demonstrated for the first time a link between hBD expression and colon cancer. This suggests that there is a significant link between innate immunity deregulation through disruption of cationic peptides (hBDs) and the potential development of colon cancer.

Publication types

  • Clinical Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Colonic Neoplasms* / genetics
  • Colonic Neoplasms* / metabolism
  • Exons*
  • Female
  • Gene Expression Regulation, Neoplastic*
  • Humans
  • Male
  • Middle Aged
  • Mutation*
  • Neoplasm Proteins* / biosynthesis
  • Neoplasm Proteins* / genetics
  • Promoter Regions, Genetic
  • RNA, Messenger / biosynthesis
  • RNA, Messenger / genetics
  • RNA, Neoplasm / biosynthesis
  • RNA, Neoplasm / genetics
  • Real-Time Polymerase Chain Reaction
  • beta-Defensins* / biosynthesis
  • beta-Defensins* / genetics

Substances

  • Neoplasm Proteins
  • RNA, Messenger
  • RNA, Neoplasm
  • beta-Defensins

Grants and funding

The authors extend their appreciation to the Deanship of Scientific Research at King Saud University for funding the work through the research group project No: RGP-VPP-260 and by a grant from the Fonds Émile-Beaulieu (Laval University Foundation).