Along the periphery of tumor nodes in T1023-treated mice, an uneven decrease in the intensity of immunostaining of the nuclei of proliferating cells for Ki-67 was determined, and the proportion of Ki-67-positive nuclei of atypical cells in these tumors was significantly lower (74%) than in the control (Figure 7; Table 3), and, on the contrary, the number of immunopositive tumor cells for Caspase-3 significantly increased, more than two times (23–29 per mm2) in comparison with the control (Figure 8; Table 4). The gene discussed is MKI67; the disease is neoplasm.