In vivo near-infrared imaging and phototherapy of tumors using a cathepsin B-activated fluorescent probe

Publication date: April 2017
Source:Biomaterials, Volume 122
Author(s): Xiaoqiang Chen, Dayoung Lee, Sungsook Yu, Gyoungmi Kim, Songyi Lee, Yejin Cho, Haengdueng Jeong, Ki Taek Nam, Juyoung Yoon
The development of multifunctional reagents for simultaneous specific near-infrared (NIR) imaging and phototherapy of tumors is of great significance. This work describes the design of a cathepsin B-activated fluorescent probe (CyA-P-CyB) and its applications as an NIR imaging probe for tumor cells and as a phototherapy reagent for tumors. In vitro experiments demonstrated that CyA-P-CyB was activated via the cleavage of a peptide linker by cathepsin B in tumor cells to produce fluorescence in the NIR region based on a FRET mechanism. MTT assays showed that the phototoxicity of CyA-P-CyB toward cells depended on the activity of cathepsin B, and the probe exhibited specific phototoxicity toward tumor cells. CyA-P-CyB was also successfully applied to the in vivo imaging and phototherapy of tumors. Histological analysis indicated that CyA-P-CyB had no cytotoxic effects on seven mouse tissues (lung, liver, heart, kidney, pancreas, spleen and brain) after the CyA-P-CyB treatment and laser irradiation.

Graphical abstract

http://ift.tt/2iLIHoQ