Tight junction protein ZO-2 is differentially expressed in normal pancreatic ducts compared to human pancreatic adenocarcinoma

Int J Cancer. 1999 Jul 2;82(1):137-44. doi: 10.1002/(sici)1097-0215(19990702)82:1<137::aid-ijc23>3.0.co;2-f.


Differential display of hamster mRNA identified a fragment present in normal pancreatic duct cells that is not expressed in pancreatic duct carcinoma cells. Sequence analysis showed an 88% and 82% identity, respectively, to the cDNA of the canine and human tight junction zo-2 gene. Semi-quantitative RT-PCR analysis of human ZO-2 revealed a striking difference in the expression of various regions of the ZO-2 transcript in normal and neoplastic cells and the presence of an abnormality at the 5'-end of mRNA. RACE analysis identified 2 human ZO-2 mRNAs that encode proteins of different lengths, designated as ZO-2A and ZO-2C. The difference between the 2 forms of ZO-2 is the absence of 23 amino acid residues at the N terminus of ZO-2C compared with ZO-2A. Although ZO-2C was expressed in normal pancreatic cells and a majority of neoplastic tissues analyzed, ZO-2A was undetectable except in one case in all of the pancreatic adenocarcinomas analyzed. This suggests the presence of a yet to be identified motif important for cell-growth regulation within the 23-amino acid residue N-terminal peptide of ZO-2A, MPVRGDRGFPPRRELSGWLRAPG.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adenocarcinoma / metabolism*
  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • Blotting, Northern
  • Blotting, Western
  • Cricetinae
  • Humans
  • Immunohistochemistry
  • Membrane Proteins / analysis
  • Membrane Proteins / genetics*
  • Molecular Sequence Data
  • Pancreatic Ducts / metabolism*
  • Pancreatic Neoplasms / metabolism*
  • RNA, Messenger / analysis
  • Reverse Transcriptase Polymerase Chain Reaction
  • Zonula Occludens-2 Protein


  • Membrane Proteins
  • RNA, Messenger
  • TJP2 protein, human
  • Zonula Occludens-2 Protein