TWIST1 and neoplasm: Interestingly, however, epithelial cells that predominate metastatic lesions suggest that EMT→MET reversal is also fundamental to circulating tumour cells (CTCs) in colonising a new metastatic niche at distal organs, attributable to loss of Twist1 signal—the same signal that orchestrates tumour invasion and vascular intravasation at early metastatic stages.