PTPA and prostate cancer: PPP2R1A and KPNB1 are particularly interesting candidate targets because PP2A activation and KPNB1 inhibition are validated therapeutic approaches in prostate cancer where both SH-BC-893 and FTY720 have demonstrated activity (Yang et al, 2019; Hu et al, 2015; McClinch et al, 2018; Rodriguez-Bravo et al, 2018; Kim et al, 2016; Lim and Wong, 2018).