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In vivo imaging of mouse tumors by a lipidated cathepsin S substrate.

ABSTRACT: The synthesis and evaluation of two cathepsin?S-specific probes is described. For long-term retention of the probe at the target site and a high signal-to-noise ratio, we introduced a lipidation approach via the simple attachment of palmitoic acid to the reporter. After cathepsin?S-specific cleavage in cultured cells and in a grafted tumor mouse model, fluorescence increased owing to dequenching and we observed an intracellular accumulation of the fluorescence in the target tissue. The lipidated probe provided a prolonged and strongly fluorescent signal in tumors when compared to the very similar non-lipidated probe, demonstrating that non-invasive tumor identification is feasable. The homing principle by probe lipidation might also work for selective administration of cytotoxic compounds to specifically reduce tumor mass.

SUBMITTER: Hu HY

PROVIDER: S-EPMC4298799 | biostudies-literature | 2014 Jul

REPOSITORIES: biostudies-literature

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In vivo imaging of mouse tumors by a lipidated cathepsin S substrate.

Hu Hai-Yu HY Vats Divya D Vizovisek Matej M Kramer Lovro L Germanier Catherine C Wendt K Ulrich KU Rudin Markus M Turk Boris B Plettenburg Oliver O Schultz Carsten C

Angewandte Chemie (International ed. in English) 20140530 29

The synthesis and evaluation of two cathepsin S-specific probes is described. For long-term retention of the probe at the target site and a high signal-to-noise ratio, we introduced a lipidation approach via the simple attachment of palmitoic acid to the reporter. After cathepsin S-specific cleavage in cultured cells and in a grafted tumor mouse model, fluorescence increased owing to dequenching and we observed an intracellular accumulation of the fluorescence in the target tissue. The lipidated ...[more]

PMID: 24888522

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