PTPA and neoplasm: As reviewed in depth elsewhere, impairment of PP2A function is a very common feature of many cancers, therefore PP2A may be considered as a tumor suppressor (Carratu, Signorile, De Rasmo, Reale, & Vacca, 2016; Grech et al., 2016; Haesen et al., 2014; Janssens & Rebollo, 2012; O'Connor, Perl, Leonard, Sangodkar, & Narla, 2017; Ruvolo, 2016; Westermarck & Hahn, 2008).