PTPA and familial pancreatic carcinoma: This led to tricyclic sulfonamide compounds such as DBK-1154 (Fig. 3C), which bind in the HEAT repeats of the PP2A scaffold protein PPP2R1A at a site proximal to the C-terminal of the catalytic subunit, eliciting robust PP2A activation and impairing growth of non small cell lung cancer, prostate and pancreatic cancers (Allen-Petersen et al., 2019; Kauko et al., 2018; McClinch et al., 2018; Sangodkar et al., 2017; Tohme et al., 2019).