Expression of SPDEF reduced the tumor burden (Figure 3A), decreased the number of Ki67 and PH3-positive cells (Figure 3C and 3D, left panels), and reduced mRNA levels of proliferation-specific genes Cdc25b, Cyclin B1, Cyclin A2, PLK1, CKS1, Aurora B and Topo2 alpha in the prostate tumors (Figure 3D, right panel). The gene discussed is PLK1; the disease is prostate neoplasm.