Calcium phosphate nanoparticles as a novel nonviral vector for efficient trasfection of DNA in cancer gene therapy

To explore an efficient gene vector in cancer gene therapy, a novel nonviral vector calcium phosphate nanoparticle (CPNP) was developed. Transmission electromicroscopy and Zeta potential demonstrated that CPNP was 23.5-34.5 nm diameters and had + 16.8 mV positive surface charges. The analysis of the CPNP-DNA complex showed CPNP could transfer foreign DNA. into targeted cells with high transfection efficiency as well as its DNA-binding property and protection of DNA from degradation. Furthermore, the CPNP-DNA complex had no obvious cytotoxicity for CNE-2 cells, while the liposome-DNA complex had certain cytotoxicity. When the CPNP combined with suicide genes yCDglyTK for nasopharyngeal carcinoma (NPC) therapy in vitro, just 24.76% (of cells survived when the wild-type CNE-2 cells were treated. with the CPNP-yCDglyTK complex plus the prodrug, 5-FC (200 mg/mL). Otherwise, the expression of yCDglyTK was detected in implanted CNE-2 tumors by reverse transcription-polymerase chain reaction (RT-PCR) analysis when the CNE-2 tumor was treated with an intratumoral injection of the CPNP-yCDglyTK complex. Our results showed that the CPNP might be a potential vector for gene therapy.