Development of novel cell-penetrating peptide Cys-CPT2,9 penetratin with high translocation ability and antitumor activity / 药学学报

ABSTRACT

To develop a cell-penetrating peptide with high membrane penetrating ability and effective antitumor activity, we designed and synthesized an analogue of penetratin, [Cys-CPT2,9] penetratin, by substitution of Gln2 and Asn9 with Cys-CPT. We investigated the transmembrane activity and antitumor activity of [Cys-CPT2,9] penetratin. The fluorescence intensity of [Cys-CPT2,9] penetratin in HeLa cells was observed by laser confocal microscopy and flow cytometry, and the cell uptake mechanism of [Cys-CPT2,9] penetratin was evaluated by using different endocytic inhibitors, finally the anti-tumor activity of [Cys-CPT2,9] penetratin was tested by MTT assay. The results showed that the membrane activity of [Cys-CPT2,9] penetratin was significantly enhanced in laser confocal microscopy and flow cytometry assay, and the intracellular fluorescence intensity was 5 times higher than penetratin. The cell uptake mechanism study of [Cys-CPT2,9] penetratin indicated that it mainly entered the cell through the clathrin and endocytosis. Moreover, [Cys-CPT2,9] penetratin exhibited anti-tumor activity against HeLa cells, and its inhibitory effect on cancer cells was stronger than CPT. [Cys-CPT2,9] penetratin is a new cell-penetrating peptide with high translocation ability, and has anti-tumor activity against HeLa cells.