Abstract:

[Abstract] Objective  To prepare the cancer targeted drug carrier using SP5-52 peptide conjugated with generation four polyamidoamine (PAMAM) dendrimer, and study its cancer cell targeted capability. Methods  SP5-52 peptide was conjugated to generation four PAMAM (G4) with succinic anhydride, and FITC was conjugated to the cancer targeted drug carrier as fluorescent probe. The cell toxicity of the carrier was detected by tetrazolium salt colorimetric test (MTT). The cellular uptake of G4-FITC and G4-FITC-SP5-52 was measured by flow cytometry. And the cellular uptake of doxorubicin (DOX) by cancer cells was observed by inverted fluorescence microscope. Results The targeted drug carrier modified by acetyl showed good biocompatibility. The cell viability was more than 80% at 4 μmol/L concentration after 24-hour incubation. Flow cytometry analysis showed that targeted carrier could target non-small cell lung cancer NCI-H460 cells, and free SP5-52 peptide could inhibit the cancer targeted capability of carrier. DOX could be encapsulated into G4-FITC-SP5-52 and showed obvious delayed release. The results of inverted fluorescence microscope showed that targeted carrier could transport more drugs into cancer cells.Conclusion G4-FITC-SP5-52 has good cancer targeting capability in vitro and might be a promising drug carrier for clinical cancer treatment.

Key words: nano-carrier, tumor targeting, PAMAM, SP5-52 peptide