IHC staining confirmed dramatic upregulated nuclear cFos and JUND levels in Pb-Cre;Ptenfl/flArid1afl/fl at 13-and 6.5-fold respectively, when compared to control Pb-Cre;Ptenfl/fl and Pb-Cre;Ptenfl/flArid1afl/+ tumours (Fig. 4c, Supplementary Fig. 6A). The gene discussed is FOS; the disease is neoplasm.