PTPA and neoplasm: To demonstrate carcinogen-induced tumor from Lgr5+ intestinal stem cells of PP2A deficient mice was not limited to DMBA, N-methyl-N-nitrosourea (MNU) and 2-amino-1-methyl-6-phenylimidazo-[4,5-b]pyridine (PhIP) were also administered in combination with tamoxifen treatment in organoid cultures derived from Lgr5-EGFP-CreERT2; Ppp2r1aflox/flox mice and from Villin-Cre; Ppp2r1aflox/flox mice.