The results suggested that the expression levels of PLK1 mRNA were higher in bladder, brain and CNS (Central Nervous System), colorectal, gastric, breast, esophageal, cervical, head and neck, ovarian, lung, liver, pancreatic cancer and lymphoma, sarcoma, leukemia compared to the normal tissues (Figure 1D). The gene discussed is PLK1; the disease is leukemia.