Endogenous H2S-Assisted Cancer-Cell-Specific Activation of Theranostics with Emission Readout

Realizing the importance of activation of the anticancer drug, its distribution, and for cancer management, a new theranostic probe has been developed. Endogenous H2S stimulated the theranostic molecular prodrug (TP-HS) which is activated in cancer cells; it monitors the actual time of formation of therapeutic agent SN-38 in cellular milieu through fluorescence imaging. Upon exposure to H2S in a similar physiological condition, the azide functionality converted to amine (−NH2) in TP-HS which allows self-immolative scission of the labile benzyl-carbonate moiety for release of rhodol and SN-38 in a concerted manner. Thus, an intense emission band centered at 548 nm has appeared for quantifying the active therapeutic component. The fluorescence image revealed that the TP-HS preferentially releases rhodol and SN-38 in colon cancer (HCT116 cells) and lung cancer cells (A549 cells) compared to normal human fibroblast cells (WI-38). Further, the dose-dependent antiproliferative activity of TP-HS against various ...