Mediated imaging and improved targeting of farnesylthiosalicylic acid delivery for pancreatic cancer via conjugation with near-infrared fluorescence heptamethine carbocyanine dye

S-trans-trans farnesylthiosalicylic acid (FTS) is a Ras inhibitor that exhibits desirable anticancer property and currently undergoing clinical trials for pancreatic cancer (PC). However, its poor water solubility and low bioavailability have severely hampered clinical applications. A strategy to improve FTS bioavailability is to develop a suitable drug delivery method. Here, we use a near-infrared fluorescence (NIRF) heptamethine carbocyanine (HC) dye conjugated with FTS (to produce FTS-148) as a drug delivery system to enhance FTS bioavailability. We further investigate its tumor-targeting functions. FTS-148 displayed better bioavailability and photophysical property, selective recognition of cancer cells. FTS-148 significantly reduced PC cell proliferation, and more effective than FTS in restricting tumor growth both in a cell-derived xenograft (CDX) model and a patient-derived tumor xenograft (PDX) model. FTS-148 can specifically recognize PC cells in mice subcutaneous models or rabbit orthotopic mode...