Front Chem. 2015 Jun 23;3:37. doi: 10.3389/fchem.2015.00037. eCollection 2015.
Frontiers in chemistry
Reik Löser, Jens Pietzsch
PMID: 26157794 PMCID: PMC4477214 DOI: 10.3389/fchem.2015.00037
Papain-like cysteine proteases bear an enormous potential as drug discovery targets for both infectious and systemic human diseases. The considerable progress in this field over the last two decades has also raised interest in the visualization of these enzymes in their native context, especially with regard to tumor imaging. After a short introduction to structure and general functions of human cysteine cathepsins, we highlight their importance for drug discovery and development and provide a critical update on the current state of knowledge toward their involvement in tumor progression, with a special emphasis on their role in therapy response. In accordance with a radiopharmaceutical point of view, the main focus of this review article will be the discussion of recently developed fluorescence and radiotracer-based imaging agents together with related molecular probes.
Keywords: cancer; carcinogenesis; extracellular enzymes; fluorescence-based probes; lysosomal cysteine proteases; metastasis; molecular imaging; radiotracers
