In comparison to tumor cells from the PT, in CTCs the expression levels of PCNA and MKI67 was reduced 495.5-fold (p-value 0.0008, two-tailed t-test) and 81.9-fold (p-value 0.0054, two-tailed t-test), respectively (Figure 5A). The gene discussed is MKI67; the disease is neoplasm.