MKI67 and neoplasm: To determine whether Akt1 ablation inhibits cell proliferation, lung tissue sections from AJEJJenv infected Akt1−/− mice at 12 (representing early neoplastic lesions) and 32 (representing advanced neoplasms) weeks post-infection were stained for the Ki67 proliferation marker and compared with similarly stained sections from WT, Akt2−/− and Akt3−/− infected mice (Figure 5A).