Fig. 1

Polarity at cellular and multicellular level. Intrinsic polarity is at basis of front and back polarity in migrating cells, focalized cilia assembly, asymmetrical inheritance as in stem cell division, and correct positioning of daughter cells in tissues by coupling with the position and orientation of the mitotic spindle. All these processes are altered during aging, resulting in stem cell exhaustion, cancer, deregulation of angiogenesis, and cell signaling and compromised barrier function