A chelating derivative of alpha-melanocyte stimulating hormone as a potential imaging agent for malignant melanoma.

Abstract

A chelating derivative of alpha-melanocyte stimulating hormone (MSH) has been synthesised, in which two molecules of the hormone are cross-linked by diethylenetriamine pentaacetic acid (DTPA). This compound, bisMSH-DTPA, was equipotent with MSH in an in vitro tyrosinase assay with Cloudman S91 melanoma cells. When DBA/2 mice bearing the same tumour were injected with bisMSH-DTPA labelled with the gamma-emitting isotope indium-111 (111In), the radioactivity became rapidly associated with the melanoma tissue. By 24 h post-injection, radioactivity in tumour tissue was significantly higher (P less than 0.001) than in spleen, lung, brain, eye and skin. Uptake of radioactivity by the tumours was inhibited by a 200-fold molar excess of MSH, whereas uptake by liver, kidney, spleen, lung, brain, eye and skin was unaffected. We conclude that bisMSH-DTPA may offer an alternative to antibody targeting in the imaging of malignant melanoma.

• Authors: D R Bard, C G Knight, D P Page-Thomas
• Journal: British journal of cancer (Br J Cancer) Vol. 62 Issue 6 Pg. 919-22 (Dec 1990) ISSN: 0007-0920 [Print] England
• PMID: 2257220 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Indium Radioisotopes
• Pentetic Acid
• Melanocyte-Stimulating Hormones

Topics

• Animals
• Drug Stability
• Indium Radioisotopes
• Melanocyte-Stimulating Hormones (analogs & derivatives, pharmacokinetics)
• Melanoma (diagnostic imaging)
• Mice
• Mice, Inbred DBA
• Pentetic Acid
• Radionuclide Imaging
• Tissue Distribution