Co-delivery of genes and drugs with nanostructured calcium carbonate for cancer therapy

By using a CaCO3 co-precipitation technique, p53 expression plasmids and doxorubicin hydrochloride (DOX) were encapsulated in nano-sized CaCO3/DNA/DOX co-precipitates for co-delivery of genes and drugs. Under a certain Ca2+/CO32- ratio in the co-precipitation, both plasmid DNA and drugs could be loaded in the CaCO3/DNA/DOX nanoparticles with high encapsulation efficiency. The in vitro cell inhibition of the CaCO3/DNA/DOX nanoparticles was evaluated in HeLa cells by a MTT assay. The results showed the simultaneous treatment by gene and drug could induce cell apoptosis and completely inhibit the cell proliferation. The CaCO3/DNA/DOX nanoparticles exhibited a high cell inhibition rate of about 75%, indicating that the CaCO3/DNA/DOX nanoparticles could effectively mediate gene transfection and deliver the drug to the cells. Compared with the gene delivery system (CaCO3/DNA nanoparticles) or the free drug DOX, the co-delivery system (CaCO3/DNA/DOX nanoparticles) exhibits enhanced cell inhibition rate. The calcium carbonate based approach has great potential in the preparation of gene and drug co-delivery systems, and the CaCO3/DNA/DOX nanoparticles have promising applications in cancer treatment.