Similar observation has been published by Oshimori et al. in 2015 [10].The cells in the external part of the cancer cell nest, located at the tumor-stroma-interface bestow mesenchymal properties with high Slug (Fig. 4 A) and low E-cadherin and KLF4 expression, whereas, the cells in the middle of the cancer cell nest retain the epithelial E-cadherin/KLF4 expression (Fig. 4 B). The gene discussed is KLF4; the disease is cancer.