Purpose: The current study examined the effects of hepatocyte growth factor/scatter factor (HGF/SF) on cell-cell dissociation, invasion, and its association with the mediated release of matrix metalloproteinase-7 (Matrilysin) on the extracellular cleavage of E-cadherin in prostate cancer cells.
Experimental design: The effects of HGF/SF on cell-cell dissociation, in vitro invasion, and on the expression of E-cadherin at both protein and mRNA levels were assessed in cells whose expression of Matrilysin was altered by treatment with antisense oligonucleotide.
Results: Incubation with HGF/SF mediated the release of active Matrilysin (M(r) 19,000), resulting in extracellular cleavage of E-cadherin from prostate cancer cells. This resultant soluble M(r) 80,000 fragment of E-cadherin was subsequently recognized upon immunoprobing with an anti-E-cadherin antibody. Both recombinant human Matrilysin (rh-Matrilysin) and/or HGF/SF increased the level of soluble E-cadherin and decreased the level of full-length (M(r) 120,000) E-cadherin as detected by Western blotting. The effects of rh-Matrilysin and HGF/SF were inhibited by an antisense oligonucleotide specifically directed toward human Matrilysin. In addition, stimulation with either rh-Matrilysin or HGF/SF resulted in disruption to the E-cadherin/beta-catenin complex, as shown by a significant increase (P < 0.05) in both cell scattering and invasion index.
Conclusions: Treatment with HGF/SF induced Matrilysin-mediated cleavage to the extracellular domain of E-cadherin, resulting in its dissociation from the cadherin/catenin complex. This provides a new mechanism in HGF/SF-induced cell scattering, resulting in a switch to a more invasive phenotype in LNCapFGC cells, as demonstrated by in vitro invasion.