In contrast to limited metastatic incidences observed in 3-month-old Pten/Arid1a DKO mice (Fig. 1i and Supplementary Fig. 1h), metastatic spreading of tumor cells to distant organs, including the lymph nodes and lungs, was found with high penetrance in PtenPC−/−; Arid1aPC−/− mice at 4 months of ages (Fig. 1i, j). The gene discussed is PTEN; the disease is neoplasm.