Complete tumor removal during surgery has a great impact on patient prognosis and survival. In order to remove the tumor tissue completely with minimal collateral damage to healthy tissue, there is a need for diagnostic tools that will differentiate between the tumor and its healthy surroundings1.
We present here the design, synthesis and characterization of a novel polymeric Turn-ON probe that is enzymatically degraded by cysteine cathepsins to generate a fluorescence signal. This polymeric Turn-ON probe was recently reported by us2 and composed of N-(2-hydroxypropyl) methacrylamide (HPMA) copolymer bearing self-quenched Cy5 fluorescent dyes. We studied the kinetics of the polymeric nano-probe on orthotopic breast cancer model in mice and showed a high tumor-to-background ratio. The signal obtained from the tumor was stable and delineated the tumor boundaries during the whole surgical procedure, enabling an accurate resection. The control groups which underwent standard surgery under white light only, or under the fluorescence guidance of the commercially-available probes ProSense® 680 or 5-Aminolevulinic acid (5-ALA) survived less time and suffered from tumor recurrence earlier than the group that underwent image-guided surgery using our Turn-ON probes3.
Our “smart” polymeric Turn-ON probe can potentially assist surgeons to decide in real time during surgery regarding the tumor margins needed to be removed, leading to improved patient outcome.
References