Recently, in order to understand the existence of E/M hybrid phenotypic state of cancer cell, a core regulatory network governing epithelial-mesenchymal plasticity had been proposed by Lu et al. 19, the core regulatory network is composed of four components (two families of E-box binding transcription factors SNAIL and ZEB, and two families of microRNAs (miRs) miR-34 and miR-200). The gene discussed is ZEB1; the disease is cancer.