As shown in Figure 1B, dose-dependent inhibition of T24 cell proliferation by submicromolar concentrations of as-APF was specifically and significantly decreased following CKAP4 knockdown (p < .001 for comparison of CKAP siRNA-treated cells compared to both controls at concentrations ≥ 1.25 nM), indicating the importance of this receptor for mediating APF antiproliferative activity in T24 bladder carcinoma cells. The gene discussed is CKAP4; the disease is urinary bladder carcinoma.