Invasion of tumorigenic HT1080 cells is impeded by blocking or downregulating the 37-kDa/67-kDa laminin receptor

J Mol Biol. 2008 May 2;378(3):530-9. doi: 10.1016/j.jmb.2008.02.004. Epub 2008 Feb 12.

Abstract

The 37-kDa/67-kDa laminin receptor precursor/laminin receptor (LRP/LR) acting as a receptor for prions and viruses is overexpressed in various cancer cell lines, and their metastatic potential correlates with LRP/LR levels. We analyzed the tumorigenic fibrosarcoma cell line HT1080 regarding 37-kDa/67-kDa LRP/LR levels and its invasive potential. Compared to the less invasive embryonic fibroblast cell line NIH3T3, the tumorigenic HT1080 cells display approximately 1.6-fold higher cell-surface levels of LRP/LR. We show that anti-LRP/LR tools interfere with the invasive potential of HT1080 cells. Anti-LRP/LR single-chain variable fragment antibody (scFv) iS18 generated by chain shuffling from parental scFv S18 and its full-length version immunoglobulin G1-iS18 reduced the invasive potential of HT1080 cells significantly by 37% and 38%, respectively. HT1080 cells transfected with lentiviral plasmids expressing small interfering RNAs directed against LRP mRNA showed reduced LRP levels by approximately 44%, concomitant with a significant decrease in the invasive potential by approximately 37%. The polysulfated glycans HM2602 and pentosan polysulfate (SP-54), both capable of blocking LRP/LR, reduced the invasive potential by 20% and 35%, respectively. Adhesion of HT1080 cells to laminin-1 was significantly impeded by scFv iS18 and immunoglobulin G1-iS18 by 60% and 68%, respectively, and by SP-54 and HM2602 by 80%, suggesting that the reduced invasive capacity achieved by these tools is due to the perturbation of the LRP/LR-laminin interaction on the cell surface. Our in vitro data suggest that reagents directed against LRP/LR or LRP mRNA such as antibodies, polysulfated glycans, or small interfering RNAs, previously shown to encompass an anti-prion activity by blocking or downregulating the prion receptor LRP/LR, might also be potential cancer therapeutics blocking metastasis by interfering with the LRP/LR-laminin interaction in neoplastic tissues.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Adhesion
  • Down-Regulation*
  • Humans
  • Laminin / metabolism
  • Mice
  • NIH 3T3 Cells
  • Neoplasm Invasiveness*
  • Plasmids / metabolism
  • PrPSc Proteins / metabolism
  • RNA, Messenger / metabolism
  • RNA, Small Interfering / metabolism
  • Receptors, Laminin / antagonists & inhibitors*
  • Receptors, Laminin / genetics
  • Receptors, Laminin / immunology
  • Tumor Cells, Cultured

Substances

  • Laminin
  • PrPSc Proteins
  • RNA, Messenger
  • RNA, Small Interfering
  • Receptors, Laminin
  • laminin 1