Bridging from Brain to Tumor Imaging: (S)-(-)- and (R)-(+)-[18F]Fluspidine for Investigation of Sigma-1 Receptors in Tumor-Bearing Mice.
Mathias KranzRalf BergmannTorsten KniessBirgit BelterChristin NeuberZhengxin CaiGang DengSteffen FischerJiangbing ZhouYiyun HuangPeter BrustWinnie Deuther-ConradJens PietzschPublished in: Molecules (Basel, Switzerland) (2018)
Sigma-1 receptors (Sig1R) are highly expressed in various human cancer cells and hence imaging of this target with positron emission tomography (PET) can contribute to a better understanding of tumor pathophysiology and support the development of antineoplastic drugs. Two Sig1R-specific radiolabeled enantiomers (S)-(-)- and (R)-(+)-[18F]fluspidine were investigated in several tumor cell lines including melanoma, squamous cell/epidermoid carcinoma, prostate carcinoma, and glioblastoma. Dynamic PET scans were performed in mice to investigate the suitability of both radiotracers for tumor imaging. The Sig1R expression in the respective tumors was confirmed by Western blot. Rather low radiotracer uptake was found in heterotopically (subcutaneously) implanted tumors. Therefore, a brain tumor model (U87-MG) with orthotopic implantation was chosen to investigate the suitability of the two Sig1R radiotracers for brain tumor imaging. High tumor uptake as well as a favorable tumor-to-background ratio was found. These results suggest that Sig1R PET imaging of brain tumors with [18F]fluspidine could be possible. Further studies with this tumor model will be performed to confirm specific binding and the integrity of the blood-brain barrier (BBB).
Keyphrases
- positron emission tomography
- pet imaging
- computed tomography
- high resolution
- prostate cancer
- endothelial cells
- type diabetes
- metabolic syndrome
- magnetic resonance imaging
- pet ct
- multiple sclerosis
- skeletal muscle
- long non coding rna
- blood brain barrier
- adipose tissue
- mass spectrometry
- south africa
- white matter
- photodynamic therapy
- fluorescence imaging
- brain injury