This is consistent with a very recent study, which showed the essential roles of ZEB1-miR200 feedback loop in the hysteresis of EMT, and that the varied reversibility of EMT can influence the metastatic potentials of cancer cells.48 Our results further suggest that ZEB1 serves as the hub for coordinating the reciprocity of E-genes and M-genes, and this coupling is closely related to the variable reversibility of EMT. The gene discussed is ZEB1; the disease is cancer.