Monitoring inflammation-cancer progression by cell viscosity, polarity and leucine aminopeptidase using multicolor fluorescent probe

Inflammation is implicated in cancer genesis and invasiveness and is frequently associated with a poor prognosis in cancer patients; thus, it becomes a focus of oncology research on how to clarify the relationship between inflammation and cancer. However, it still lacks a simple and rapid method for simultaneous multichannel detection of multiple indicators of the inflammation-cancer progression. Herein, we have presented a probe VLAP for multicolor and ratio imaging of viscosity, polarity and leucine aminopeptidase (LAP) simultaneously. VLAP produces a strong fluorescence signal at 700 nm in high viscosity, also it can react with LAP to form the fluorophore VLAPF providing a fluorescence signal at 600 nm. Furthermore, the generated VLAPF is sensitive to environmental polarity and can be monitored for changes in polarity through ratio imaging. The probe VLAP could reveal altered mitochondrial viscosity in inflammatory cells, altered LAP in cancer cells, and decreased mitochondrial polarity in cells during epithelial-mesenchymal transition. Additionally, VLAP has also been successfully used to evaluate changes in the microenvironment during the inflammatory response in zebrafish. As a matter of fact, this work has provided a general molecular design methodology for multiple species imaging but also has revealed the changes in viscosity, polarity, and LAP in the progression of inflammation and cancer based on this multicolor VLAP probe.