Figure 2.

Western blot showing the relative expression of (A) ErbB-2 (~ 185 kDa) in ovcar-3 and HIO-80 total cell lysates (40 μg each). Cytoplasmic marker α-tubulin (~ 50 kDa) was used to determine equal loading of proteins. (B) for determining the cell binding properties of ¹¹¹In-labeled peptides, approximately 2.0 ×10⁶ cells per tube were incubated at 37°C for different time intervals with 3.0 ×10⁴cpm ¹¹¹In-DOTA-GSG-KCCYSL or scrambled ¹¹¹In-DOTA-GSG-KYLCSC (n=3 each time point). While ¹¹¹In-DOTA-GSG-KCCYSL binding to human ovcar-3 carcinoma cells was observed, only minimal binding was seen with normal ovarian epithelial HIO-80 cells that express very little ErbB-2. ¹¹¹In-DOTA-GSG-KYLCSC did not show significant binding to either ovcar-3 or HIO-80 cell lines.