RESUMO
Translocator protein (TSPO) is involved in several cellular mechanisms such as steroidogenesis, immunomodulation, cell proliferation and differentiation. Overexpressed in several neurodegenerative diseases and brain cancer, TSPO radioligands have been developed over the last 20 years in positron emission tomography (PET) imaging. Recently, TSPO radioligands have extended beyond their initial application due to their specific binding to activated macrophages, making them a compelling biomarker for deciphering the intricacies of the tumor microenvironment (TME). In this review, we synthesized recent progress from the evaluation of TSPO-specific PET tracers in various peripheral tumor models and highlighted the hurdles and limitations associated with heterogeneous uptake in healthy tissue and tumor regions to achieve the clinical development of such a radiotracer.
Assuntos
Neoplasias Encefálicas , Tomografia por Emissão de Pósitrons , Receptores de GABA , Humanos , Receptores de GABA/metabolismo , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/diagnóstico , Tomografia por Emissão de Pósitrons/métodos , Animais , Compostos Radiofarmacêuticos/metabolismo , Microambiente TumoralRESUMO
123I-ioflupane (DaTSCAN®, GE) is a well-known ready-to-use radiopharmaceutical employed as a visualizing tool of the brain dopamine transporter receptor distribution. According to the Summary of Product Characteristics recommendations, we evaluated the stability of the DaTSCAN® after a 0.9% sodium chloride solution dilution. No significant increase in free 123I-iodide was revealed between diluted and undiluted samples over a 1-h timeframe. This stability in sodium chloride can compensate for potential dilution error and offers a suitable alternative method for syringing DaTSCAN®.