PAI-1 Regulates the Invasive Phenotype in Human Cutaneous Squamous Cell Carcinoma
Figure 1
Combination stimulation with TGF-β1+EGF induces a plastic response in HaCaT II-4 cells. A model system was devised in which small colonies of HaCaT II-4 cells, seeded on tissue culture plastic, were serum-starved followed by addition of TGF-β1 (1 ng/mL) + EGF (10 ng/mL). The induced acquisition of a spindle-shaped, highly migratory phenotype, resulted in marked colony dispersal within 24–48 hours. Cell scattering was accompanied by the loss of E-cadherin (green) and α3 integrin (red) immunostaining at cell-cell junctions, and the gain of several mesenchymal markers, such as α-smooth muscle actin and vimentin with construction of a well-developed vimentin filament network. Induced PAI-1 expression (within 6 hours) was a prominent and early feature of growth factor-stimulated EMT.
