Fig. 2.

HFn-Dox specifically targets tumor cells in vitro and in vivo. (A) Flow cytometric analysis of the specific binding of HFn and HFn-Dox to HT-29 colon cancer cells. (B) Inhibition of the binding of Cy5.5-labeled HFn to HT-29 cells by unlabeled HFn or HFn-Dox. The IC₅₀ values of HFn and HFn-Dox were 0.25 ± 0.010 μM and 0.26 ± 0.012 μM, respectively (n = 4, bars represent means ± SD). (C) In vivo nuclear imaging of HT-29 tumors. Mice were injected i.v. with 400 µCi of ¹²⁵I-labeled HFn-Dox and imaged for 24 h. Arrows mark the tumor location.