In summary, the immunofluorescence analysis confirmed that i) PLEKHA7 expression was restricted to the apical region of epithelial gland cells, either facing the lumen in normal ductal carcinomas, or facing the stroma in the inverted polarity micropapillary carcinomas, ii) was distinct from that of either E-cadherin/p120ctn, or cingulin/ZO-1, and iii) was undetectable in lobular carcinomas. The gene discussed is TJP1; the disease is carcinoma.