Binding of 125I after administration of 125I-EGF-dextran, 125I-EGF or 125I to human bladder cancer spheroids.
The binding of a targeting agent, 125I-EGF-dextran, to epidermal growth factor (EGF) receptors in tumour spheroids of a human bladder cancer cell line was studied. The accumulation of radioactivity was continuous up to at least 48 h in the peripheral cells of the spheroids, which in comparison with the binding pattern of 125I-EGF indicated that the cells had a limited capacity to degrade the EGF-dextran. The 125I-EGF-dextran was of two different sizes, 28 and 76 kDa, but this did not affect the binding patterns and the results were very similar. The EGF-dextran conjugates had qualities that are of interest for tumour targeting.
Biomedical Radiation Sciences, Rudbeck Laboratory, Uppsala University, Sweden. anna.sjostrom@bms.uu.se
A
A
Sjöström
P
P
Bue
P
P
Malmstrom
J
J
Carlsson
D000818:Animals; D003911:Dextrans / Q000378:metabolism*; D004815:Epidermal Growth Factor / Q000378:metabolism*; D006801:Humans; D007457:Iodine Radioisotopes / Q000008:administration & dosage / Q000378:metabolism*; D051379:Mice; D008970:Molecular Weight; D011845:Radio; D018874:Spheroids, Cellular / Q000378:metabolism*; D001749:Urinary Bladder Neoplasms / Q000378:metabolism* / Q000473:pathology
D003911:Dextrans; D007457:Iodine Radioisotopes; C067291:epidermal growth factor-dextran conjugate; D004815:Epidermal Growth Factor