Modulation of invasive properties of murine squamous carcinoma cells by heterologous expression of cathepsin B and cystatin C

Int J Cancer. 1999 Nov 12;83(4):526-31. doi: 10.1002/(sici)1097-0215(19991112)83:4<526::aid-ijc15>;2-m.


Murine SCC-VII squamous carcinoma cells have the capacity to penetrate reconstituted basement membranes (Matrigel) in vitro. The invasion of Matrigel layers by SCC-VII cells was significantly reduced by E-64, a specific inhibitor of lysosomal cysteine proteinases. The cathepsin-B-selective E-64 derivative, CA-074, inhibited penetration of Matrigel by SCC-VII cells to the same extent, indicating a major role for this particular lysosomal enzyme in extracellular-matrix degradation during squamous-carcinoma-cell invasion. SCC-VII cells were stably transfected with a cDNA encoding human procathepsin B, in an attempt to modulate the invasive properties of the cell line. The transfected cells expressed the heterologous gene, secreted increased amounts of procathepsin B and displayed enhanced invasive potential. In vivo, the activity of cathepsin B is strictly regulated by endogenous inhibitors. SCC-VII cells were therefore also stably transfected with a cDNA encoding human cystatin C, the most potent cysteine-proteinase inhibitor in mammalian tissues. The expression of this transgene resulted in the production of active recombinant cystatin C and a pronounced reduction in Matrigel invasion. These studies demonstrate that the invasive properties of squamous-cell carcinomas can be changed by modulation of the balance between cathepsin B and its endogenous inhibitors, and provide further evidence for the involvement of this lysosomal cysteine proteinase in tumour invasion and metastasis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Blotting, Northern
  • Carcinoma, Squamous Cell / enzymology
  • Carcinoma, Squamous Cell / metabolism*
  • Carcinoma, Squamous Cell / pathology
  • Cathepsin B / antagonists & inhibitors
  • Cathepsin B / biosynthesis*
  • Cathepsin B / genetics
  • Chemotaxis
  • Collagen / metabolism
  • Culture Media, Conditioned / metabolism
  • Cystatin C
  • Cystatins / biosynthesis*
  • Cystatins / genetics
  • Cysteine Proteinase Inhibitors / biosynthesis*
  • Cysteine Proteinase Inhibitors / genetics
  • Drug Combinations
  • Enzyme Precursors / antagonists & inhibitors
  • Enzyme Precursors / biosynthesis*
  • Enzyme Precursors / genetics
  • Extracellular Matrix / metabolism
  • Gene Expression
  • Humans
  • Laminin / metabolism
  • Mice
  • Neoplasm Invasiveness / genetics
  • Proteoglycans / metabolism
  • Recombinant Proteins / biosynthesis
  • Recombinant Proteins / genetics
  • Transfection
  • Tumor Cells, Cultured


  • CST3 protein, human
  • Cst3 protein, mouse
  • Culture Media, Conditioned
  • Cystatin C
  • Cystatins
  • Cysteine Proteinase Inhibitors
  • Drug Combinations
  • Enzyme Precursors
  • Laminin
  • Proteoglycans
  • Recombinant Proteins
  • matrigel
  • Collagen
  • procathepsin B
  • Cathepsin B