In spheroids derived from mouse gliobastoma 35 and rat neuroma 46-1, the expression levels of the Cdkn2a and Mki67 genes were reduced manifold (glioblastoma 35 demonstrated a fivefold decrease in Cdkn2a and sevenfold decrease in Mki67 expression, while neuroma 46-1 showed a fourteenfold decrease in both genes’ expression, p < 0.01); in addition, spheroids 46-1 demonstrated the decrease in Pik3cg expression and a more than fourfold increase in Ncad expression, p < 0.05. The gene discussed is MKI67; the disease is glioblastoma.