Regulation of the expression of the prostate-specific antigen by claudin-7

J Membr Biol. 2003 Aug 1;194(3):187-97. doi: 10.1007/s00232-003-2038-4.

Abstract

Claudins are a family of proteins involved in forming tight junctions between cells. Here we describe two forms of claudin-7 (CLDN-7), a full-length form of CLDN-7 with 211 amino-acid residues and a C-terminal truncated form with 158 amino-acid residues. These two forms of CLDN-7 are able to regulate the expression of a tissue-specific protein, the prostate-specific antigen (PSA), in the LNCaP prostate cancer cell line. We also found that the expression of CLDN-7 is responsive to androgen stimulation in the LNCaP cell line, suggesting that this protein is involved in the regulatory mechanism of androgen. Both forms of claudin-7 are expressed in human prostate, kidney and lung samples, and in most samples, the full-length form of claudin-7 was predominant. However, in some prostate samples from healthy individuals, the truncated form of claudin-7 is predominantly expressed. Our results demonstrated that unlike other claudins, CLDN-7 has both structural and regulatory functions, and the two forms of CLDN-7 may be related to cell differentiation in organ development.

Publication types

  • Comparative Study

MeSH terms

  • Adenocarcinoma / metabolism
  • Adenocarcinoma / pathology*
  • Amino Acid Sequence
  • Cell Line, Tumor / drug effects
  • Cell Line, Tumor / metabolism
  • Claudins
  • DNA, Complementary / genetics
  • Gene Expression Profiling
  • Gene Expression Regulation, Neoplastic / physiology*
  • Humans
  • Male
  • Membrane Proteins / biosynthesis
  • Membrane Proteins / chemistry
  • Membrane Proteins / genetics
  • Membrane Proteins / physiology*
  • Molecular Sequence Data
  • Neoplasm Proteins / biosynthesis
  • Neoplasm Proteins / chemistry
  • Neoplasm Proteins / genetics
  • Neoplasm Proteins / physiology*
  • Organ Specificity
  • Prostate-Specific Antigen / biosynthesis*
  • Prostate-Specific Antigen / genetics
  • Prostatic Neoplasms / metabolism
  • Prostatic Neoplasms / pathology*
  • Protein Isoforms / chemistry
  • Protein Isoforms / physiology
  • Protein Structure, Tertiary
  • RNA, Messenger / biosynthesis
  • RNA, Neoplasm / biosynthesis
  • Recombinant Fusion Proteins / genetics
  • Recombinant Fusion Proteins / physiology
  • Structure-Activity Relationship
  • Subtraction Technique
  • Tight Junctions / physiology
  • Transfection

Substances

  • CLDN7 protein, human
  • Claudins
  • DNA, Complementary
  • Membrane Proteins
  • Neoplasm Proteins
  • Protein Isoforms
  • RNA, Messenger
  • RNA, Neoplasm
  • Recombinant Fusion Proteins
  • Prostate-Specific Antigen