Palbociclib-derived multifunctional molecules for lysosomal targeting and diagnostic-therapeutic integration.

Aim: Lysosomal pH changes are associated with drug resistance, cell growth and invasion of tumors, but effective and specific real-time monitoring of lysosomal pH compounds for cancer therapy is lacking. Materials & methods: Here, based on the covalent linkage of the anticancer drug palbociclib and fluorescent dye fluorescein isothiocyanate (FITC), we designed and developed a novel palbociclib-derived multifunctional molecule (Pal-FITC) for lysosomal targeting and diagnostic therapeutic integration. Results & discussion: Pal-FITC fluoresces is 20-fold stronger than that of FITC and shows a linear response in the pH range of 4.0-8.2 (R 2  = 0.9901). Pal-FITC blocks cells in G1 phase via Cyclin D-CDK4/6-Rb . Conclusion: Our study provides new strategies for tumor-targeted imaging and personalized therapy.