Abstract: Objective To explore the metabolic characteristics of heptamethine cyanine near-infrared (NIR) fluorescence dye MHI-148 in hepatocellular carcinoma (HCC) xenograft model.Methods Human HCC cell Hep3B was co-cultured with NIR dye MHI-148 solution.The specific accumulation of MHI-148 on tumor cells was observed under fluorescence microscope.Hep3B cells were implanted subcutaneously into nude mice to establish a transplant model.Two weeks later,MHI-148 dye was injected intraperitoneally into tumor bearing nude mice and detected by NIR fluorescence optical imaging.The fluorescence intensity both on the tumor site and the organs of the nude mice was measured at different time point,the tumor fluorescence intensity (tumor,T) and the adjacent normal tissue (background,B) was continuously detected and the maximum T/B value was calculated.Results MHI-148 dyes could be specifically accumulated in HCC cells,and Hep3B cells labeled with green fluoresence protein (GFP) were identified.When MHI-148 was injected into nude mice bearing subcutaneous HCC tumor,the fluorescence intensity per unit area (cm²) of the tumor site reached 8.35×10⁹ after 24 hours,while other organs have less fluorescence aggregation.The ratio of T/B at the site of the tumor gradually increased and reached peak value at 24 hours.Conclusion The hepatocellular carcinoma cells can be specifically recognized by heptamethine cyanine dye MHI-148.The site of subcutaneous HCC tumor can be identified through NIR fluoresence optical imaging.

Key words: Heptamethine cyanine dye, Near-infrared (NIR), Optical imaging, Hepatocellular carcinoma(HCC), Animal models