Fig. 2.

Schematic diagram showing effects of complete and partial EMT on cancer cell migration with focus on HIF-1α mediated induction of EMT. Complete EMT leads to transition of epithelial cancer cells to mesenchymal cells which can show mesenchymal migration or can undergo mesenchymal to amoeboid transition (MAT) leading to amoeboid migration. On the other hand, partial EMT retains epithelial (cell adhesion junctions) and mesenchymal (motility) properties leading to collective cell migration characterized by the presence of leader cells (in hybrid E/M state) at the invasive front and follower cells (in epithelial state) forming the bulk of the cell cluster. In addition, follower cells can convert to leader cells under conditions such as nutrient depletion, possibly through partial EMT. Under hypoxia, collectively migrating cells can also undergo collective to amoeboid transition (CAT) in HIF-1α dependent manner. Lower panel shows the effect of hypoxia-induced HIF-1α on the regulators of EMT. Direct HIF-1α mediated regulation of EMT regulators during partial EMT remains to be better understood.