As shown in Supplementary Fig. S12, similarly intense fluorescence signals are observed in pure DBT-stained HepG2 cells and L02 cells, revealing that pure DBT is not able to differentiate cancer cells (overexpressed LAPTM4B) and normal cells (low LAPTM4B expression) like DBT-2EEGIHGHHIISVG does. Here, LAPTM4B is linked to cancer.