Neonatal exposure to estradiol/bisphenol A alters promoter methylation and expression of Nsbp1 and Hpcal1 genes and transcriptional programs of Dnmt3a/b and Mbd2/4 in the rat prostate gland throughout life

Endocrinology. 2012 Jan;153(1):42-55. doi: 10.1210/en.2011-1308. Epub 2011 Nov 22.

Abstract

Evidence supporting an early origin of prostate cancer is growing. We demonstrated previously that brief exposure of neonatal rats to estradiol or bisphenol A elevated their risk of developing precancerous lesions in the prostate upon androgen-supported treatment with estradiol as adults. Epigenetic reprogramming may be a mechanism underlying this inductive event in early life, because we observed overexpression of phosphodiesterase 4D variant 4 (Pde4d4) through induction of hypomethylation of its promoter. This epigenetic mark was invisible in early life (postnatal d 10), becoming apparent only after sexual maturation. Here, we asked whether other estrogen-reprogrammable epigenetic marks have similar or different patterns in gene methylation changes throughout life. We found that hypomethylation of the promoter of nucleosome binding protein-1 (Nsbp1), unlike Pde4d4, is an early and permanent epigenetic mark of neonatal exposure to estradiol/bisphenol A that persists throughout life, unaffected by events during adulthood. In contrast, hippocalcin-like 1 (Hpcal1) is a highly plastic epigenetic mark whose hypermethylation depends on both type of early-life exposure and adult-life events. Four of the eight genes involved in DNA methylation/demethylation showed early and persistent overexpression that was not a function of DNA methylation at their promoters, including genes encoding de novo DNA methyltransferases (Dnmt3a/b) and methyl-CpG binding domain proteins (Mbd2/4) that have demethylating activities. Their lifelong aberrant expression implicates them in early-life reprogramming and prostate carcinogenesis during adulthood. We speculate that the distinctly different fate of early-life epigenetic marks during adulthood reflects the complex nature of lifelong editing of early-life epigenetic reprogramming.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Animals, Newborn
  • Azacitidine / analogs & derivatives
  • Azacitidine / pharmacology
  • Base Sequence
  • Benzhydryl Compounds
  • Calcium-Binding Proteins / genetics*
  • DNA (Cytosine-5-)-Methyltransferases / genetics
  • DNA Methylation / drug effects
  • DNA Methyltransferase 3A
  • DNA Methyltransferase 3B
  • DNA Primers / genetics
  • DNA-Binding Proteins / genetics
  • Decitabine
  • Estradiol / administration & dosage*
  • Estradiol / toxicity*
  • Gene Expression / drug effects
  • HMGN Proteins / antagonists & inhibitors
  • HMGN Proteins / genetics*
  • Male
  • Nerve Tissue Proteins / genetics*
  • Phenols / administration & dosage*
  • Phenols / toxicity*
  • Promoter Regions, Genetic / drug effects
  • Prostate / drug effects*
  • Prostate / metabolism*
  • RNA, Small Interfering / genetics
  • Rats
  • Rats, Sprague-Dawley

Substances

  • Benzhydryl Compounds
  • Calcium-Binding Proteins
  • DNA Primers
  • DNA-Binding Proteins
  • HMGN Proteins
  • Hpcal1 protein, rat
  • MBD2 protein
  • Nerve Tissue Proteins
  • Phenols
  • RNA, Small Interfering
  • Estradiol
  • Decitabine
  • DNA (Cytosine-5-)-Methyltransferases
  • DNA Methyltransferase 3A
  • Azacitidine
  • bisphenol A