The cellular localization of peptides often provides information about their probable function, so we investigated whether PDHPS1 could penetrate cell membrane and its main localization in cells. FITC- labeled PDHPS1 was added into the culture medium of SKOV3 or A2780 cells with a final concentration of 50 mmol/L, after 24-hour coculture, laser-scanning confocal microscopy was used to monitor the distribution of peptide, and results showed that PDHPS1 could get inside cells and widely distributed in cytoplasm and nucleus of cells (Supplementary Fig. S1B).