Fig. 5.
Proliferative index of PSA-positive prostate CTCs. (A) CTCs isolated from two patients with metastatic prostate cancer costained using antibodies against PSA and the proliferation marker Ki67. Representative high-resolution images of CTCs costained with DAPI (nuclear stain), PSA (cytoplasmic stain, green), and Ki67 (nuclear stain, red) are shown. Scale bars, 10 μm. (B) Numerical analysis of 10 patients with metastatic prostate cancer showing the concentration of serum PSA, number of PSA-stained CTCs, and the fraction of PSA-positive CTCs that are also positive for Ki67 [proliferative fraction; % Ki67(+)]. The clinical status of each patient at the time of analysis—untreated, responsive to ADT (castration-sensitive), or castration-resistant—is indicated.