Integrin expression on cell adhesion function and up-regulation of P125FAK and paxillin in metastatic renal carcinoma cells

Connect Tissue Res. 1996;34(3):161-74. doi: 10.3109/03008209609000696.


Integrins from normal human renal cortex epithelial cells (RCEC) and from four renal carcinoma lines (metastatic Caki-1, non-metastatic Caki-2, metastatic ACHN, and non-metastatic 769-P) were compared by immunoprecipitation with specific anti-integrin antibodies. Integrin alpha 2 was present in normal RCEC, but absent in all four tumor lines. There was a 2.0-3.0 fold decrease of alpha 3 and beta 1 in localized tumor lines, and a further 5.0-7.0 fold decrease in metastatic lines over their expression in normal renal cells. No alpha V was detected in Caki-1 cells. The greatest adhesion of all cells occurred in the presence of a stimulatory anti-alpha 3 antibody, mediated by specific matrix proteins employed as substrates, while anti-beta 1 treatment dramatically inhibited cell attachment on collagen IV, plasma fibronectin, laminin and merosin substrates. In addition, the mRNA expression of focal adhesion kinase (p125FAK) and paxillin were up-regulated (2.0-2.5 fold increase) in the metastatic Caki-1 cells over normal RCEC. The alteration of integrin subunits alpha 2, alpha 3, alpha V, beta 1, as well as p125FAK and paxillin may contribute to the pathogenicity and/or metastatic propensity of renal epithelial tumors. The up-regulation of paxillin independently or in concert with p125FAK as shown in this study indicates its significant role as a potential marker of metastasis in renal carcinoma cells.

Publication types

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

MeSH terms

  • Blotting, Western
  • Cell Adhesion Molecules / genetics
  • Cell Adhesion Molecules / metabolism*
  • Cell Adhesion*
  • Cell Line
  • Cytoskeletal Proteins / genetics
  • Cytoskeletal Proteins / metabolism*
  • Electrophoresis, Polyacrylamide Gel
  • Focal Adhesion Kinase 1
  • Focal Adhesion Protein-Tyrosine Kinases
  • Humans
  • Integrins / metabolism*
  • Kidney Neoplasms / metabolism*
  • Kidney Neoplasms / pathology
  • Neoplasm Metastasis
  • Nucleic Acid Hybridization
  • Paxillin
  • Phosphoproteins / genetics
  • Phosphoproteins / metabolism*
  • Precipitin Tests
  • Protein-Tyrosine Kinases / genetics
  • Protein-Tyrosine Kinases / metabolism*
  • RNA, Messenger
  • Tumor Cells, Cultured
  • Up-Regulation*


  • Cell Adhesion Molecules
  • Cytoskeletal Proteins
  • Integrins
  • PXN protein, human
  • Paxillin
  • Phosphoproteins
  • RNA, Messenger
  • Protein-Tyrosine Kinases
  • Focal Adhesion Kinase 1
  • Focal Adhesion Protein-Tyrosine Kinases
  • PTK2 protein, human