Cyclin A2: At the crossroads of cell cycle and cell invasion

Figure 1 Presumptive regulatory network involving cyclin A2 and RhoA in the control of mitosis and epithelial to mesenchymal transition. Cyclin A2 degradation by the proteasome in mid mitosis is essential for mitosis to proceed. However, recent observations show that a small fraction of cyclin A2 persists beyond metaphase and is degraded by autophagy. Cyclin A2 participates in the modulation of RhoA activity; since this GTPase is involved in both cell rounding early in mitosis and later, in the formation of the cleavage furrow, this suggests that cyclin A2 plays also a role in cytokinesis. Taken together, these data point to this cyclin as a potential mediator of cell-niche interactions, its down regulation leading to EMT via PLC and RhoA converging pathways. EMT: Epithelial to mesenchymal transition; PLC: Phospholipase C.