Figure 7.

Expression of endogenous p120^ctn in the nucleus and influences by E-cadherin and phorbol ester. Human breast cancer cells SK-BR-3 (a) and MDA-MB-231 (b) express p120^ctn both within and outside the nucleus. Human colon cancer SW480 cells (c) express p120^ctn mainly at cell–cell contacts but also in cytoplasm and nucleus. SK-BR-3 cells were transfected transiently with E-cadherin cDNA and stained for E-cadherin (not shown) and p120^ctn (d). Two cells that were positive for E-cadherin show accumulation of p120^ctn outside the nucleus (arrows). An MDA-MB-231 transfectant, which was stably expressing E-cadherin cDNA, shows colocalization of E-cadherin (not shown) and p120^ctn at cell–cell contacts only (e). Upon treatment of SW480 cells with 250 ng/ml of phorbol ester for 3 h, p120^ctn relocalized from extranuclear sites to the nucleus (f). (Bar = 18 μm.)