Multifunctional Theranostic Probe Based on the Pim-1 Kinase Inhibitor with the Function of Tracking pH Fluctuations during Treatment

Currently,kinase inhibitors have been applied in the diagnosisor treatment of cancer with their unique advantages. It is of greatsignificance to develop some comprehensive theranostic reagents basedon kinase inhibitors to improve the performance of reagents for biomedicalapplications. Besides, tracking changes in the intracellular environment(e.g., pH) during cancer development and drug delivery is also criticalfor cancer research and treatment. Therefore, it is an urgent desireto design some novel multifunctional reagents based on kinase inhibitorstrategies that can trace changes in the microenvironment of cancercells. In this paper, a multifunctional theranostic reagent basedon Pim-1 kinase inhibitor 5-bromobenzofuran-2-carboxylic acid is proposed.The theranostic probe binds to tumor-specific Pim-1 kinase, releasesstrong fluorescence, and produces cytotoxicity, thus achieving cellscreening and killing effects. Furthermore, the probe can specificallytarget lysosomes and sensitively respond to pH. It can be used totrack the pH changes in the intracellular environment under conditionsof autophagy and external stimulation, as a visual tool to monitorpH fluctuations during cancer treatment. In conclusion, this simplebut multifunctional theranostic reagent proposed in this work is expectedto provide a promising method for cancer diagnosis and therapy.