Characterization of 3-[123I]iodo-L-alpha-methyl tyrosine ([123I]IMT) transport into human Ewing's sarcoma cells in vitro

Nucl Med Biol. 2001 Feb;28(2):123-8. doi: 10.1016/s0969-8051(00)00186-4.


3-[(123)I]Iodo-L-alpha-methyl tyrosine ([(123)I]IMT) scintigraphy of extracranial malignant tumors has been described, but little is known about the transport systems involved in [(123)I]IMT uptake into extracranial tumor cells. Here, the precise kinetics of [(123)I]IMT transport into human Ewing's sarcoma cells (VH-64) was determined. The apparent Michaelis constant was of high affinity value (K(m)=41.7+/-3.9 microM) and maximum transport velocitiy amounted to V(max)=20.7+/-0.6 nmol x mg protein(-1) x 10 min(-1). Inhibition experiments revealed the predominance of [(123)I]IMT uptake via sodium-independent system L.

MeSH terms

  • Biological Transport
  • Bone Neoplasms
  • Humans
  • Iodine Radioisotopes / pharmacokinetics*
  • Kinetics
  • Methyltyrosines / pharmacokinetics*
  • Sarcoma, Ewing
  • Tumor Cells, Cultured


  • Iodine Radioisotopes
  • Methyltyrosines
  • 3-iodo-alpha-methyltyrosine