In a paper in this month's freely-available online global health journal PLoS Medicine, Roland Haubner of the University Hospital for Nuclear Medicine in Innsbruck, Austria, and colleagues describe how a compound they have developed can be used together with highly sensitive positron emission tomography scanning to measure the amount of new blood vessel growth in some tumours.
New blood vessel growth - angiogenesis - is important for the growth of tumours; several drugs target angiogenesis specifically. The compound previously developed by Haubner and colleagues is a fluorine-labeled glycopeptide, (18F-Galacto-RGD), which binds tightly to a receptor - αvβ3 integrin - expressed in some tumours, especially in the blood vessels.
As well as a role in angiogenesis, integrins are important in holding tumour cells together and connecting them with the extracellular matrix. What happens when these interactions break down is one of the keys to determining how tumours metastasise.
Haubner and colleagues' work, in a mouse with human melanoma and in a small study of patients with tumours including melanoma, suggests that the marker is truly reflecting the in vivo level of the integrin.
Hence the marker could be used to identify tumours that express this marker, assess the degree of new vessel formation in tumours, and help in the planning and monitoring of anti-angiogenic therapies which target this integrin.
MEDICA.de; Source: Public Library of Science