Abstract
Fluorescent polymer platforms reveal different aspects of tumour mechanobiology, but the strength of the evidence behind their optical readouts varies. This narrative review distinguishes calibrated physical measurements, mechanically active therapies assessed by independent assays, and biochemical or delivery readouts. We classify polymer roles as emission generation, mechanical coupling, chemical gating, and carriage or localisation. Among the selected studies, polymer-assisted molecular rotors measured local microviscosity in mouse CT26 tumours, while fluorescent polyacrylamide inclusions enabled intravital solid-stress inference from calibrated deformation. PEG–gold tethers measured receptor tension in cancer-cell culture. Mechanically responsive fluorophores in synthetic networks remain enabling technologies without tumour validation. Our quantitative comparison covers formulation properties, optical operating conditions, calibration, and demonstrated biological settings, labelling unreported values and inapplicable metrics separately. A cholesterol-modifying polyrotaxane illustrates therapy supported by independent cellular mechanics assays; its fluorescence tracks distribution. Protease, pH, oxygen, and transcript probes provide complementary microenvironment or treatment-response information without directly measuring tissue stiffness. The evidence reviewed here establishes neither a clinically validated polymer-fluorescence biomarker of tumour mechanics nor a universal cross-platform performance ranking. Progress requires a defined physical variable and compartment, maintained formulation integrity, and evidence that the measured change informs a functional treatment outcome.