Figure 1.

Cell non-autonomous effect of PTEN on tumor suppression. Conventional PTEN via exosomes, or PTEN-Long via an unknown mechanism, can be secreted from donor cells and enter recipient cells to antagonize PI3K signaling, induce apoptosis, and regulate cellular metabolism (Top panel). Likewise, exported mutant PTEN or secreted mutant PTEN-Long from cancer cells can enter the adjacent normal cells to interfere with wild-type PTEN functions, thus disrupting normal cell homeostasis and inducing a more pronounced tumor-prone condition (Bottom panel).