Expression of E-cadherin and its repressor snail in placental tissue of normal, preeclamptic and HELLP pregnancies

Virchows Arch. 2007 Feb;450(2):195-202. doi: 10.1007/s00428-006-0343-x.


Incomplete invasion of extravillous trophoblasts (EVT) is thought to be associated with complications of pregnancy. Snail, a zinc-finger transcription factor represses the transcription of the cell adhesion molecule E-cadherin. The aim of this study was to investigate the expression of E-cadherin and Snail in placental tissue with preeclampsia or HELLP. Placental tissues were obtained from five patients with HELLP syndrome, seven patients with preeclampsia and seven patients after a normal term birth and analysed for Snail and E-cadherin immunoreactivity with specific monoclonal antibodies. Immunohistochemical staining of the placental tissue was analysed using an immunoreactivity score for the evaluation of staining intensity. In preeclamptic EVT, Snail immunoreactivity showed a significant 1.7-fold increase, accompanied by a significant 1.9-fold reduction of E-cadherin immunoreactivity. A 1.7-fold increase of Snail and in parallel a 1.3-fold reduction of E-cadherin was observed in EVT of HELLP placentas although without statistical significance. Loss of E-cadherin can be observed during epithelial-mesenchymal transition (EMT), a key process in normal development and trophoblast differentiation. Snail represses the transcription of E-cadherin triggering a complete EMT. Results obtained in this study showed changes of Snail and E-cadherin immunoreactivity in preeclamptic placentas that could be accompanied with an altered EMT in trophoblasts.

MeSH terms

  • Cadherins / analysis*
  • Decidua / chemistry
  • Female
  • HELLP Syndrome / metabolism*
  • Humans
  • Immunohistochemistry
  • Placenta / chemistry*
  • Pregnancy
  • Snail Family Transcription Factors
  • Transcription Factors / analysis*
  • Trophoblasts / chemistry


  • Cadherins
  • Snail Family Transcription Factors
  • Transcription Factors