Figure 7.

Relationship between ADAM17-mediated Dsg2 cleavage and EGFR activity. (A) SCC68 cells were treated overnight with DMSO, PMA, GM, TAPI, PKI, or PMA, and PKI in starvation media containing 0.25 mM calcium. When indicated, cells were also stimulated with EGF for 1 h before lysis. Whole cell lysates were analyzed by immunoblotting for Dsg2, phosphotyrosine, EGFR, and tubulin. (B) SCC68 cells were transfected with GAPDH, ADAM10, or ADAM17 siRNA and analyzed by Western blotting 96 h after transfection for Dsg2, phosphotyrosine, EGFR, ADAM10, ADAM17, and tubulin. Dsg2 cleavage was blocked in MMP inhibited and ADAM17-deficient cells despite robust EGFR phosphorylation.