A multifunctional α-Fe2O3@PEDOT core-shell nanoplatform for gene and photothermal combination anticancer therapy

Exploration of versatile nanoplatforms within one single nanostructure for multidisciplinary treatment modalities, especially achieving a synergistic therapeutic efficacy of combinational gene/photothermal cancer therapy is still a great challenge in biomedicine and nanotechnology. In this study, a unique photothermal nanocarrier has successfully been designed and developed for a combination of gene therapy (GT) and photothermal therapy (PTT) of cancer cells. Surface-engineered iron oxides (alpha-Fe2O3) nanoparticles (NPs) with poly(3,4-ethylenedioxythiophene) (PEDOT) polymer coatings are synthesized using a one-pot in situ oxidative polymerization method. The results show that the as-prepared alpha-Fe2O3@PEDOT core-shell NPs with a uniform particle size exhibit positively charged surfaces, facilitating efficient siRNA Bcl-2 (B-cell lymphoma-2) uptake for delivery to breast cancer cells. More importantly, alpha-Fe2O3@PEDOT core-shell NPs not only display good biocompatibility and water dispersibility but also strong optical absorption enhancement in the Vis-NIR region as compared to alpha-Fe2O3 NPs. The obtained alpha-Fe2O3@PEDOT core-shell NPs show an efficient photothermal conversion efficacy (eta = 54.3%) and photostability under NIR laser irradiation. As a result, both in vitro and in vivo biological studies on two types of breast cancer cells/tumors treated with alpha-Fe2O3@PEDOT-siRNA nanocomplexes demonstrate high cancer cell apoptosis and tumor inhibition induced by synergistic GT/PTT therapy under mild conditions compared to an individual GT or PTT alone. Taken together, this is the first example of the use of an alpha-Fe2O3@PEDOT core-shell nanoagent as a siRNA delivery nanocarrier for highly effective gene/photothermal combination anticancer therapy.

Automated summary

This study successfully designed and developed a unique photothermal nanocarrier for combination gene therapy and photothermal therapy in cancer treatment. The nanocarrier demonstrated good biocompatibility and enhanced optical absorption, resulting in efficient treatment of breast cancer cells. In vitro and in vivo studies showed significant apoptosis of cancer cells and tumor inhibition when the nanocarrier was used for two different types of breast cancer cells/tumors. This is the first example of utilizing this nanocarrier for highly effective gene and photothermal combination therapy.