Fig. 4
From: Urokinase-type plasminogen activator receptor (uPAR) as a therapeutic target in cancer
(Reproduced with permission from reference [172]. Copyright 2017, Pergamon)
uPAR-targeted, CTSE-responsive gold nanoclusters as a PDT/PTT platform. A Schematic of the synthetic route used to produce the gold nanoclusters in three steps: CTSE-cleavable CRQAGFSL-5-ALA (Peptide-5-ALA, prodrug) and CRQAGFSL-Cy5.5 (Peptide-cy5.5) were covalently conjugated to the nanospheres, cross-linked with 1,9-nonanedithiol to produce spherical gold nanoclusters, and finally coated with the U11 peptide modified PEG layer to yield the uPAR-targeted, CTSE-responsive PDT/PTT platform. B Overview of image-guided PDT/PTT in therapeutic PDAC. Upon injection, the nanoclusters first targeted the pancreatic tumour tissue. The selective cleavage of the CTSE-sensitive peptide activated the fluorescence signal of the NIR cyanine dye Cy5.5 to guide PDT/PTT therapy using confocal laser endomicroscopy. CTSE cathepsin E, 5-ALA 5-aminolevulinic acid, Cy5.5 cyanine 5.5, PDAC pancreatic ductal adenocarcinoma, NIR near infrared, PEG polyethylene glycol, ROS reactive oxygen species