Table 1

Stability constants for the therapeutic metal ions binding to Tf (log K) and the uptake of these metals in various cell lines

Metal IonsLog K1LogK2Cell Lines UsedSpecial RemarksReferences
Ga3+ 19.718.8Human leukemic HL60TfR-dependent and TfR-independent mechanism, Ga-Tf inhibits iron incorporation Harris and Pecoraro, 1983; Chitambar et al., 1987, 1988;Chitambar and Zivkovic-Gilgenbach, 1990
Small cell lung Cancer cellsTF and TfR are important Weiner et al., 1996
EMT-6 sarcomaTfR-mediated uptake Larson et al., 1979
Murine tumor cellExogenous Tf stimulated Ga3+ uptake significantly Harris and Sephton, 1977
LymphomasTfR pathway Habeshaw et al., 1983
In3+ 18.516.6Human and rat reticulocytesIn-Tf binds to cell membrane, but minimal transfer into the cell Beamish and Brown, 1974; Harris et al., 1994
Human leukemia cell lineCellular proliferation inhibited by In-Tf and TfR expression increased Moran and Seligman, 1989
Bi3+ 19.418.6BeWo placental cancer cells; IEC-6 rat intestinal cellsRecognized by cells, interfere with iron uptake Li et al., 1996a; Guo et al., 2000; Zhang et al., 2001
Ti4+ BeWo placental cancer cellsTfR-mediated uptake by cells Guo et al., 2000
Ru3+ Jurkat Tag cell; tumor and abscess; human colon cancer cellRu3+ toxicity increased; Ru-Tf in localization tumor and abscess Som et al., 1983; Frasca et al., 2001
SW707Tf as a carrier for Ru3+ Kratz et al., 1996