Enzyme-Mediated Nanostructure Transition for Enhanced CEST MRI in Triple-Negative Breast Cancer

Motivation: Small molecule CEST agents are often rapidly cleared from tumors, which adversely affects the CEST MRI signal for triple-negative breast cancer (TNBC). Goal(s): Our objective was to selectively generate nanostructures within TNBC tumors to enhance the CEST signal. Approach: We designed a morphologically variable nanoparticle that transforms into nanofibers in response to enzymes overexpressed in TNBC cells. This transformation activates the CEST signal, increases probe concentration, and prolongs retention time within the tumor. Results: The engineered nanoparticles significantly enhanced CEST signal intensity at tumor sites while minimizing signal in healthy tissue. Impact: This enzyme-mediated nanostructure transition strategy specifically enhances CEST MRI in tumor cells, facilitating the development of more effective diagnostic and therapeutic probes for various diseases.